1 | /********************************************************************** |
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2 | * $Id: lwgeom_functions_analytic.c 4168 2009-06-11 16:44:03Z pramsey $ |
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3 | * |
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4 | * PostGIS - Spatial Types for PostgreSQL |
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5 | * http://postgis.refractions.net |
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6 | * Copyright 2001-2005 Refractions Research Inc. |
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7 | * |
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8 | * This is free software; you can redistribute and/or modify it under |
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9 | * the terms of the GNU General Public Licence. See the COPYING file. |
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10 | * |
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11 | **********************************************************************/ |
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12 | |
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13 | #include "postgres.h" |
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14 | #include "fmgr.h" |
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15 | #include "liblwgeom.h" |
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16 | #include "lwgeom_pg.h" |
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17 | #include "math.h" |
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18 | #include "lwgeom_rtree.h" |
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19 | #include "lwalgorithm.h" |
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20 | |
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21 | |
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22 | /*********************************************************************** |
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23 | * Simple Douglas-Peucker line simplification. |
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24 | * No checks are done to avoid introduction of self-intersections. |
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25 | * No topology relations are considered. |
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26 | * |
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27 | * --strk@keybit.net; |
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28 | ***********************************************************************/ |
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29 | |
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30 | |
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31 | /* Prototypes */ |
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32 | void DP_findsplit2d(POINTARRAY *pts, int p1, int p2, int *split, double *dist); |
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33 | POINTARRAY *DP_simplify2d(POINTARRAY *inpts, double epsilon); |
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34 | LWLINE *simplify2d_lwline(const LWLINE *iline, double dist); |
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35 | LWPOLY *simplify2d_lwpoly(const LWPOLY *ipoly, double dist); |
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36 | LWCOLLECTION *simplify2d_collection(const LWCOLLECTION *igeom, double dist); |
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37 | LWGEOM *simplify2d_lwgeom(const LWGEOM *igeom, double dist); |
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38 | Datum LWGEOM_simplify2d(PG_FUNCTION_ARGS); |
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39 | Datum ST_LineCrossingDirection(PG_FUNCTION_ARGS); |
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40 | Datum ST_LocateBetweenElevations(PG_FUNCTION_ARGS); |
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41 | |
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42 | double determineSide(POINT2D *seg1, POINT2D *seg2, POINT2D *point); |
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43 | int isOnSegment(POINT2D *seg1, POINT2D *seg2, POINT2D *point); |
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44 | int point_in_ring(POINTARRAY *pts, POINT2D *point); |
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45 | int point_in_polygon(LWPOLY *polygon, LWPOINT *point); |
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46 | int point_in_multipolygon(LWMPOLY *mpolygon, LWPOINT *point); |
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47 | int point_in_ring_rtree(RTREE_NODE *root, POINT2D *point); |
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48 | int point_in_polygon_rtree(RTREE_NODE **root, int ringCount, LWPOINT *point); |
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49 | int point_in_multipolygon_rtree(RTREE_NODE **root, int polyCount, int ringCount, LWPOINT *point); |
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50 | |
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51 | |
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52 | /* |
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53 | * Search farthest point from segment p1-p2 |
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54 | * returns distance in an int pointer |
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55 | */ |
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56 | void |
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57 | DP_findsplit2d(POINTARRAY *pts, int p1, int p2, int *split, double *dist) |
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58 | { |
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59 | int k; |
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60 | POINT2D pa, pb, pk; |
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61 | double tmp; |
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62 | |
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63 | LWDEBUG(4, "DP_findsplit called"); |
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64 | |
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65 | *dist = -1; |
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66 | *split = p1; |
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67 | |
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68 | if (p1 + 1 < p2) |
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69 | { |
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70 | |
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71 | getPoint2d_p(pts, p1, &pa); |
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72 | getPoint2d_p(pts, p2, &pb); |
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73 | |
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74 | LWDEBUGF(4, "DP_findsplit: P%d(%f,%f) to P%d(%f,%f)", |
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75 | p1, pa.x, pa.y, p2, pb.x, pb.y); |
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76 | |
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77 | for (k=p1+1; k<p2; k++) |
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78 | { |
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79 | getPoint2d_p(pts, k, &pk); |
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80 | |
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81 | LWDEBUGF(4, "DP_findsplit: P%d(%f,%f)", k, pk.x, pk.y); |
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82 | |
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83 | /* distance computation */ |
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84 | tmp = distance2d_pt_seg(&pk, &pa, &pb); |
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85 | |
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86 | if (tmp > *dist) |
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87 | { |
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88 | *dist = tmp; /* record the maximum */ |
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89 | *split = k; |
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90 | |
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91 | LWDEBUGF(4, "DP_findsplit: P%d is farthest (%g)", k, *dist); |
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92 | } |
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93 | } |
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94 | |
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95 | } /* length---should be redone if can == 0 */ |
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96 | |
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97 | else |
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98 | { |
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99 | LWDEBUG(3, "DP_findsplit: segment too short, no split/no dist"); |
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100 | } |
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101 | |
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102 | } |
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103 | |
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104 | |
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105 | POINTARRAY * |
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106 | DP_simplify2d(POINTARRAY *inpts, double epsilon) |
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107 | { |
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108 | int *stack; /* recursion stack */ |
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109 | int sp=-1; /* recursion stack pointer */ |
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110 | int p1, split; |
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111 | double dist; |
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112 | POINTARRAY *outpts; |
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113 | int ptsize = pointArray_ptsize(inpts); |
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114 | |
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115 | /* Allocate recursion stack */ |
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116 | stack = lwalloc(sizeof(int)*inpts->npoints); |
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117 | |
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118 | p1 = 0; |
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119 | stack[++sp] = inpts->npoints-1; |
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120 | |
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121 | LWDEBUGF(2, "DP_simplify called input has %d pts and %d dims (ptsize: %d)", inpts->npoints, inpts->dims, ptsize); |
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122 | |
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123 | /* allocate space for output POINTARRAY */ |
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124 | outpts = palloc(sizeof(POINTARRAY)); |
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125 | outpts->dims = inpts->dims; |
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126 | outpts->npoints=1; |
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127 | outpts->serialized_pointlist = palloc(ptsize*inpts->npoints); |
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128 | memcpy(getPoint_internal(outpts, 0), getPoint_internal(inpts, 0), |
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129 | ptsize); |
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130 | |
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131 | LWDEBUG(3, "DP_simplify: added P0 to simplified point array (size 1)"); |
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132 | |
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133 | do |
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134 | { |
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135 | |
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136 | DP_findsplit2d(inpts, p1, stack[sp], &split, &dist); |
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137 | |
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138 | LWDEBUGF(3, "DP_simplify: farthest point from P%d-P%d is P%d (dist. %g)", p1, stack[sp], split, dist); |
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139 | |
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140 | if (dist > epsilon) |
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141 | { |
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142 | stack[++sp] = split; |
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143 | } |
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144 | else |
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145 | { |
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146 | outpts->npoints++; |
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147 | memcpy(getPoint_internal(outpts, outpts->npoints-1), |
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148 | getPoint_internal(inpts, stack[sp]), |
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149 | ptsize); |
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150 | |
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151 | LWDEBUGF(4, "DP_simplify: added P%d to simplified point array (size: %d)", stack[sp], outpts->npoints); |
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152 | |
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153 | p1 = stack[sp--]; |
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154 | } |
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155 | |
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156 | LWDEBUGF(4, "stack pointer = %d", sp); |
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157 | } |
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158 | while (! (sp<0) ); |
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159 | |
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160 | /* |
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161 | * If we have reduced the number of points realloc |
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162 | * outpoints array to free up some memory. |
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163 | * Might be turned on and off with a SAVE_MEMORY define ... |
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164 | */ |
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165 | if ( outpts->npoints < inpts->npoints ) |
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166 | { |
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167 | outpts->serialized_pointlist = repalloc( |
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168 | outpts->serialized_pointlist, |
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169 | ptsize*outpts->npoints); |
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170 | if ( outpts->serialized_pointlist == NULL ) |
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171 | { |
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172 | elog(ERROR, "Out of virtual memory"); |
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173 | } |
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174 | } |
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175 | |
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176 | lwfree(stack); |
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177 | return outpts; |
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178 | } |
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179 | |
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180 | LWLINE * |
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181 | simplify2d_lwline(const LWLINE *iline, double dist) |
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182 | { |
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183 | POINTARRAY *ipts; |
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184 | POINTARRAY *opts; |
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185 | LWLINE *oline; |
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186 | |
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187 | LWDEBUG(2, "simplify2d_lwline called"); |
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188 | |
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189 | ipts = iline->points; |
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190 | opts = DP_simplify2d(ipts, dist); |
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191 | oline = lwline_construct(iline->SRID, NULL, opts); |
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192 | |
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193 | return oline; |
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194 | } |
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195 | |
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196 | LWPOLY * |
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197 | simplify2d_lwpoly(const LWPOLY *ipoly, double dist) |
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198 | { |
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199 | POINTARRAY *ipts; |
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200 | POINTARRAY **orings = NULL; |
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201 | LWPOLY *opoly; |
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202 | int norings=0, ri; |
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203 | |
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204 | LWDEBUGF(2, "simplify_polygon3d: simplifying polygon with %d rings", ipoly->nrings); |
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205 | |
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206 | orings = (POINTARRAY **)palloc(sizeof(POINTARRAY *)*ipoly->nrings); |
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207 | |
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208 | for (ri=0; ri<ipoly->nrings; ri++) |
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209 | { |
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210 | POINTARRAY *opts; |
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211 | |
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212 | ipts = ipoly->rings[ri]; |
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213 | |
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214 | opts = DP_simplify2d(ipts, dist); |
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215 | |
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216 | |
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217 | if ( opts->npoints < 2 ) |
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218 | { |
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219 | /* There as to be an error in DP_simplify */ |
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220 | elog(NOTICE, "DP_simplify returned a <2 pts array"); |
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221 | pfree(opts); |
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222 | continue; |
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223 | } |
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224 | |
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225 | if ( opts->npoints < 4 ) |
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226 | { |
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227 | pfree(opts); |
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228 | |
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229 | LWDEBUGF(3, "simplify_polygon3d: ring%d skipped ( <4 pts )", ri); |
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230 | |
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231 | if ( ri ) continue; |
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232 | else break; |
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233 | } |
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234 | |
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235 | |
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236 | LWDEBUGF(3, "simplify_polygon3d: ring%d simplified from %d to %d points", ri, ipts->npoints, opts->npoints); |
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237 | |
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238 | |
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239 | /* |
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240 | * Add ring to simplified ring array |
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241 | * (TODO: dinamic allocation of pts_per_ring) |
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242 | */ |
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243 | orings[norings] = opts; |
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244 | norings++; |
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245 | |
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246 | } |
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247 | |
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248 | LWDEBUGF(3, "simplify_polygon3d: simplified polygon with %d rings", norings); |
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249 | |
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250 | if ( ! norings ) return NULL; |
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251 | |
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252 | opoly = lwpoly_construct(ipoly->SRID, NULL, norings, orings); |
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253 | |
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254 | return opoly; |
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255 | } |
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256 | |
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257 | LWCOLLECTION * |
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258 | simplify2d_collection(const LWCOLLECTION *igeom, double dist) |
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259 | { |
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260 | unsigned int i; |
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261 | unsigned int ngeoms=0; |
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262 | LWGEOM **geoms = lwalloc(sizeof(LWGEOM *)*igeom->ngeoms); |
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263 | LWCOLLECTION *out; |
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264 | |
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265 | for (i=0; i<igeom->ngeoms; i++) |
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266 | { |
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267 | LWGEOM *ngeom = simplify2d_lwgeom(igeom->geoms[i], dist); |
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268 | if ( ngeom ) geoms[ngeoms++] = ngeom; |
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269 | } |
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270 | |
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271 | out = lwcollection_construct(TYPE_GETTYPE(igeom->type), igeom->SRID, |
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272 | NULL, ngeoms, geoms); |
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273 | |
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274 | return out; |
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275 | } |
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276 | |
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277 | LWGEOM * |
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278 | simplify2d_lwgeom(const LWGEOM *igeom, double dist) |
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279 | { |
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280 | switch (TYPE_GETTYPE(igeom->type)) |
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281 | { |
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282 | case POINTTYPE: |
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283 | case MULTIPOINTTYPE: |
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284 | return lwgeom_clone(igeom); |
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285 | case LINETYPE: |
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286 | return (LWGEOM *)simplify2d_lwline( |
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287 | (LWLINE *)igeom, dist); |
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288 | case POLYGONTYPE: |
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289 | return (LWGEOM *)simplify2d_lwpoly( |
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290 | (LWPOLY *)igeom, dist); |
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291 | case MULTILINETYPE: |
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292 | case MULTIPOLYGONTYPE: |
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293 | case COLLECTIONTYPE: |
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294 | return (LWGEOM *)simplify2d_collection( |
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295 | (LWCOLLECTION *)igeom, dist); |
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296 | default: |
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297 | lwerror("simplify2d_lwgeom: unknown geometry type: %d", |
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298 | TYPE_GETTYPE(igeom->type)); |
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299 | } |
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300 | return NULL; |
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301 | } |
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302 | |
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303 | PG_FUNCTION_INFO_V1(LWGEOM_simplify2d); |
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304 | Datum LWGEOM_simplify2d(PG_FUNCTION_ARGS) |
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305 | { |
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306 | PG_LWGEOM *geom = (PG_LWGEOM *) PG_DETOAST_DATUM(PG_GETARG_DATUM(0)); |
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307 | LWGEOM *in = lwgeom_deserialize(SERIALIZED_FORM(geom)); |
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308 | LWGEOM *out; |
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309 | PG_LWGEOM *result; |
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310 | double dist = PG_GETARG_FLOAT8(1); |
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311 | |
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312 | out = simplify2d_lwgeom(in, dist); |
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313 | if ( ! out ) PG_RETURN_NULL(); |
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314 | |
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315 | /* COMPUTE_BBOX TAINTING */ |
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316 | if ( in->bbox ) lwgeom_add_bbox(out); |
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317 | |
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318 | result = pglwgeom_serialize(out); |
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319 | |
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320 | PG_RETURN_POINTER(result); |
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321 | } |
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322 | |
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323 | /*********************************************************************** |
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324 | * --strk@keybit.net; |
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325 | ***********************************************************************/ |
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326 | |
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327 | /*********************************************************************** |
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328 | * Interpolate a point along a line, useful for Geocoding applications |
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329 | * SELECT line_interpolate_point( 'LINESTRING( 0 0, 2 2'::geometry, .5 ) |
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330 | * returns POINT( 1 1 ). |
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331 | * Works in 2d space only. |
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332 | * |
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333 | * Initially written by: jsunday@rochgrp.com |
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334 | * Ported to LWGEOM by: strk@refractions.net |
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335 | ***********************************************************************/ |
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336 | |
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337 | Datum LWGEOM_line_interpolate_point(PG_FUNCTION_ARGS); |
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338 | |
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339 | PG_FUNCTION_INFO_V1(LWGEOM_line_interpolate_point); |
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340 | Datum LWGEOM_line_interpolate_point(PG_FUNCTION_ARGS) |
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341 | { |
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342 | PG_LWGEOM *geom = (PG_LWGEOM *)PG_DETOAST_DATUM(PG_GETARG_DATUM(0)); |
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343 | double distance = PG_GETARG_FLOAT8(1); |
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344 | LWLINE *line; |
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345 | LWPOINT *point; |
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346 | POINTARRAY *ipa, *opa; |
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347 | POINT4D pt; |
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348 | uchar *srl; |
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349 | int nsegs, i; |
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350 | double length, slength, tlength; |
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351 | |
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352 | if ( distance < 0 || distance > 1 ) |
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353 | { |
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354 | elog(ERROR,"line_interpolate_point: 2nd arg isnt within [0,1]"); |
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355 | PG_RETURN_NULL(); |
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356 | } |
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357 | |
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358 | if ( lwgeom_getType(geom->type) != LINETYPE ) |
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359 | { |
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360 | elog(ERROR,"line_interpolate_point: 1st arg isnt a line"); |
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361 | PG_RETURN_NULL(); |
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362 | } |
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363 | |
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364 | line = lwline_deserialize(SERIALIZED_FORM(geom)); |
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365 | ipa = line->points; |
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366 | |
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367 | /* If distance is one of the two extremes, return the point on that |
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368 | * end rather than doing any expensive computations |
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369 | */ |
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370 | if ( distance == 0.0 || distance == 1.0 ) |
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371 | { |
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372 | if ( distance == 0.0 ) |
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373 | getPoint4d_p(ipa, 0, &pt); |
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374 | else |
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375 | getPoint4d_p(ipa, ipa->npoints-1, &pt); |
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376 | |
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377 | opa = pointArray_construct((uchar *)&pt, |
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378 | TYPE_HASZ(line->type), |
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379 | TYPE_HASM(line->type), |
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380 | 1); |
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381 | point = lwpoint_construct(line->SRID, 0, opa); |
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382 | srl = lwpoint_serialize(point); |
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383 | /* We shouldn't need this, the memory context is getting freed on the next line. |
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384 | lwpoint_free(point); */ |
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385 | PG_RETURN_POINTER(PG_LWGEOM_construct(srl, line->SRID, 0)); |
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386 | } |
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387 | |
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388 | /* Interpolate a point on the line */ |
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389 | nsegs = ipa->npoints - 1; |
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390 | length = lwgeom_pointarray_length2d(ipa); |
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391 | tlength = 0; |
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392 | for ( i = 0; i < nsegs; i++ ) |
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393 | { |
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394 | POINT4D p1, p2; |
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395 | POINT4D *p1ptr=&p1, *p2ptr=&p2; /* don't break |
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396 | * strict-aliasing rules |
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397 | */ |
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398 | |
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399 | getPoint4d_p(ipa, i, &p1); |
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400 | getPoint4d_p(ipa, i+1, &p2); |
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401 | |
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402 | /* Find the relative length of this segment */ |
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403 | slength = distance2d_pt_pt((POINT2D*)p1ptr, (POINT2D*)p2ptr)/length; |
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404 | |
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405 | /* If our target distance is before the total length we've seen |
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406 | * so far. create a new point some distance down the current |
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407 | * segment. |
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408 | */ |
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409 | if ( distance < tlength + slength ) |
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410 | { |
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411 | double dseg = (distance - tlength) / slength; |
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412 | interpolate_point4d(&p1, &p2, &pt, dseg); |
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413 | opa = pointArray_construct((uchar *)&pt, |
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414 | TYPE_HASZ(line->type), |
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415 | TYPE_HASM(line->type), |
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416 | 1); |
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417 | point = lwpoint_construct(line->SRID, 0, opa); |
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418 | srl = lwpoint_serialize(point); |
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419 | /* We shouldn't need this, the memory context is getting freed on the next line |
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420 | lwpoint_free(point); */ |
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421 | PG_RETURN_POINTER(PG_LWGEOM_construct(srl, line->SRID, 0)); |
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422 | } |
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423 | tlength += slength; |
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424 | } |
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425 | |
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426 | /* Return the last point on the line. This shouldn't happen, but |
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427 | * could if there's some floating point rounding errors. */ |
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428 | getPoint4d_p(ipa, ipa->npoints-1, &pt); |
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429 | opa = pointArray_construct((uchar *)&pt, |
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430 | TYPE_HASZ(line->type), |
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431 | TYPE_HASM(line->type), |
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432 | 1); |
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433 | point = lwpoint_construct(line->SRID, 0, opa); |
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434 | srl = lwpoint_serialize(point); |
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435 | /* We shouldn't need this, the memory context is getting freed on the next line |
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436 | lwpoint_free(point); */ |
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437 | PG_RETURN_POINTER(PG_LWGEOM_construct(srl, line->SRID, 0)); |
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438 | } |
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439 | /*********************************************************************** |
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440 | * --jsunday@rochgrp.com; |
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441 | ***********************************************************************/ |
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442 | |
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443 | /*********************************************************************** |
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444 | * |
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445 | * Grid application function for postgis. |
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446 | * |
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447 | * WHAT IS |
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448 | * ------- |
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449 | * |
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450 | * This is a grid application function for postgis. |
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451 | * You use it to stick all of a geometry points to |
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452 | * a custom grid defined by its origin and cell size |
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453 | * in geometry units. |
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454 | * |
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455 | * Points reduction is obtained by collapsing all |
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456 | * consecutive points falling on the same grid node and |
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457 | * removing all consecutive segments S1,S2 having |
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458 | * S2.startpoint = S1.endpoint and S2.endpoint = S1.startpoint. |
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459 | * |
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460 | * ISSUES |
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461 | * ------ |
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462 | * |
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463 | * Only 2D is contemplated in grid application. |
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464 | * |
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465 | * Consecutive coincident segments removal does not work |
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466 | * on first/last segments (They are not considered consecutive). |
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467 | * |
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468 | * Grid application occurs on a geometry subobject basis, thus no |
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469 | * points reduction occurs for multipoint geometries. |
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470 | * |
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471 | * USAGE TIPS |
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472 | * ---------- |
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473 | * |
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474 | * Run like this: |
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475 | * |
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476 | * SELECT SnapToGrid(<geometry>, <originX>, <originY>, <sizeX>, <sizeY>); |
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477 | * |
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478 | * Grid cells are not visible on a screen as long as the screen |
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479 | * point size is equal or bigger then the grid cell size. |
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480 | * This assumption may be used to reduce the number of points in |
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481 | * a map for a given display scale. |
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482 | * |
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483 | * Keeping multiple resolution versions of the same data may be used |
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484 | * in conjunction with MINSCALE/MAXSCALE keywords of mapserv to speed |
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485 | * up rendering. |
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486 | * |
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487 | * Check also the use of DP simplification to reduce grid visibility. |
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488 | * I'm still researching about the relationship between grid size and |
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489 | * DP epsilon values - please tell me if you know more about this. |
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490 | * |
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491 | * |
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492 | * --strk@keybit.net; |
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493 | * |
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494 | ***********************************************************************/ |
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495 | |
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496 | #define CHECK_RING_IS_CLOSE |
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497 | #define SAMEPOINT(a,b) ((a)->x==(b)->x&&(a)->y==(b)->y) |
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498 | |
---|
499 | typedef struct gridspec_t |
---|
500 | { |
---|
501 | double ipx; |
---|
502 | double ipy; |
---|
503 | double ipz; |
---|
504 | double ipm; |
---|
505 | double xsize; |
---|
506 | double ysize; |
---|
507 | double zsize; |
---|
508 | double msize; |
---|
509 | } |
---|
510 | gridspec; |
---|
511 | |
---|
512 | |
---|
513 | /* Forward declarations */ |
---|
514 | LWGEOM *lwgeom_grid(LWGEOM *lwgeom, gridspec *grid); |
---|
515 | LWCOLLECTION *lwcollection_grid(LWCOLLECTION *coll, gridspec *grid); |
---|
516 | LWPOINT * lwpoint_grid(LWPOINT *point, gridspec *grid); |
---|
517 | LWPOLY * lwpoly_grid(LWPOLY *poly, gridspec *grid); |
---|
518 | LWLINE *lwline_grid(LWLINE *line, gridspec *grid); |
---|
519 | POINTARRAY *ptarray_grid(POINTARRAY *pa, gridspec *grid); |
---|
520 | Datum LWGEOM_snaptogrid(PG_FUNCTION_ARGS); |
---|
521 | Datum LWGEOM_snaptogrid_pointoff(PG_FUNCTION_ARGS); |
---|
522 | static int grid_isNull(const gridspec *grid); |
---|
523 | #if POSTGIS_DEBUG_LEVEL > 0 |
---|
524 | static void grid_print(const gridspec *grid); |
---|
525 | #endif |
---|
526 | |
---|
527 | /* A NULL grid is a grid in which size in all dimensions is 0 */ |
---|
528 | static int |
---|
529 | grid_isNull(const gridspec *grid) |
---|
530 | { |
---|
531 | if ( grid->xsize==0 && |
---|
532 | grid->ysize==0 && |
---|
533 | grid->zsize==0 && |
---|
534 | grid->msize==0 ) return 1; |
---|
535 | else return 0; |
---|
536 | } |
---|
537 | |
---|
538 | #if POSTGIS_DEBUG_LEVEL > 0 |
---|
539 | /* Print grid using given reporter */ |
---|
540 | static void |
---|
541 | grid_print(const gridspec *grid) |
---|
542 | { |
---|
543 | lwnotice("GRID(%g %g %g %g, %g %g %g %g)", |
---|
544 | grid->ipx, grid->ipy, grid->ipz, grid->ipm, |
---|
545 | grid->xsize, grid->ysize, grid->zsize, grid->msize); |
---|
546 | } |
---|
547 | #endif |
---|
548 | |
---|
549 | /* |
---|
550 | * Stick an array of points to the given gridspec. |
---|
551 | * Return "gridded" points in *outpts and their number in *outptsn. |
---|
552 | * |
---|
553 | * Two consecutive points falling on the same grid cell are collapsed |
---|
554 | * into one single point. |
---|
555 | * |
---|
556 | */ |
---|
557 | POINTARRAY * |
---|
558 | ptarray_grid(POINTARRAY *pa, gridspec *grid) |
---|
559 | { |
---|
560 | POINT4D pbuf; |
---|
561 | int ipn, opn; /* point numbers (input/output) */ |
---|
562 | DYNPTARRAY *dpa; |
---|
563 | POINTARRAY *opa; |
---|
564 | |
---|
565 | LWDEBUGF(2, "ptarray_grid called on %p", pa); |
---|
566 | |
---|
567 | dpa=dynptarray_create(pa->npoints, pa->dims); |
---|
568 | |
---|
569 | for (ipn=0, opn=0; ipn<pa->npoints; ++ipn) |
---|
570 | { |
---|
571 | |
---|
572 | getPoint4d_p(pa, ipn, &pbuf); |
---|
573 | |
---|
574 | if ( grid->xsize ) |
---|
575 | pbuf.x = rint((pbuf.x - grid->ipx)/grid->xsize) * |
---|
576 | grid->xsize + grid->ipx; |
---|
577 | |
---|
578 | if ( grid->ysize ) |
---|
579 | pbuf.y = rint((pbuf.y - grid->ipy)/grid->ysize) * |
---|
580 | grid->ysize + grid->ipy; |
---|
581 | |
---|
582 | if ( TYPE_HASZ(pa->dims) && grid->zsize ) |
---|
583 | pbuf.z = rint((pbuf.z - grid->ipz)/grid->zsize) * |
---|
584 | grid->zsize + grid->ipz; |
---|
585 | |
---|
586 | if ( TYPE_HASM(pa->dims) && grid->msize ) |
---|
587 | pbuf.m = rint((pbuf.m - grid->ipm)/grid->msize) * |
---|
588 | grid->msize + grid->ipm; |
---|
589 | |
---|
590 | dynptarray_addPoint4d(dpa, &pbuf, 0); |
---|
591 | |
---|
592 | } |
---|
593 | |
---|
594 | opa = dpa->pa; |
---|
595 | lwfree(dpa); |
---|
596 | |
---|
597 | return opa; |
---|
598 | } |
---|
599 | |
---|
600 | LWLINE * |
---|
601 | lwline_grid(LWLINE *line, gridspec *grid) |
---|
602 | { |
---|
603 | LWLINE *oline; |
---|
604 | POINTARRAY *opa; |
---|
605 | |
---|
606 | opa = ptarray_grid(line->points, grid); |
---|
607 | |
---|
608 | /* Skip line3d with less then 2 points */ |
---|
609 | if ( opa->npoints < 2 ) return NULL; |
---|
610 | |
---|
611 | /* TODO: grid bounding box... */ |
---|
612 | oline = lwline_construct(line->SRID, NULL, opa); |
---|
613 | |
---|
614 | return oline; |
---|
615 | } |
---|
616 | |
---|
617 | LWPOLY * |
---|
618 | lwpoly_grid(LWPOLY *poly, gridspec *grid) |
---|
619 | { |
---|
620 | LWPOLY *opoly; |
---|
621 | int ri; |
---|
622 | POINTARRAY **newrings = NULL; |
---|
623 | int nrings = 0; |
---|
624 | double minvisiblearea; |
---|
625 | |
---|
626 | /* |
---|
627 | * TODO: control this assertion |
---|
628 | * it is assumed that, since the grid size will be a pixel, |
---|
629 | * a visible ring should show at least a white pixel inside, |
---|
630 | * thus, for a square, that would be grid_xsize*grid_ysize |
---|
631 | */ |
---|
632 | minvisiblearea = grid->xsize * grid->ysize; |
---|
633 | |
---|
634 | nrings = 0; |
---|
635 | |
---|
636 | LWDEBUGF(3, "grid_polygon3d: applying grid to polygon with %d rings", |
---|
637 | poly->nrings); |
---|
638 | |
---|
639 | for (ri=0; ri<poly->nrings; ri++) |
---|
640 | { |
---|
641 | POINTARRAY *ring = poly->rings[ri]; |
---|
642 | POINTARRAY *newring; |
---|
643 | |
---|
644 | #if POSTGIS_DEBUG_LEVEL >= 4 |
---|
645 | POINT2D p1, p2; |
---|
646 | getPoint2d_p(ring, 0, &p1); |
---|
647 | getPoint2d_p(ring, ring->npoints-1, &p2); |
---|
648 | if ( ! SAMEPOINT(&p1, &p2) ) |
---|
649 | LWDEBUG(4, "Before gridding: first point != last point"); |
---|
650 | #endif |
---|
651 | |
---|
652 | newring = ptarray_grid(ring, grid); |
---|
653 | |
---|
654 | /* Skip ring if not composed by at least 4 pts (3 segments) */ |
---|
655 | if ( newring->npoints < 4 ) |
---|
656 | { |
---|
657 | pfree(newring); |
---|
658 | |
---|
659 | LWDEBUGF(3, "grid_polygon3d: ring%d skipped ( <4 pts )", ri); |
---|
660 | |
---|
661 | if ( ri ) continue; |
---|
662 | else break; /* this is the external ring, no need to work on holes */ |
---|
663 | } |
---|
664 | |
---|
665 | #if POSTGIS_DEBUG_LEVEL >= 4 |
---|
666 | getPoint2d_p(newring, 0, &p1); |
---|
667 | getPoint2d_p(newring, newring->npoints-1, &p2); |
---|
668 | if ( ! SAMEPOINT(&p1, &p2) ) |
---|
669 | LWDEBUG(4, "After gridding: first point != last point"); |
---|
670 | #endif |
---|
671 | |
---|
672 | LWDEBUGF(3, "grid_polygon3d: ring%d simplified from %d to %d points", ri, |
---|
673 | ring->npoints, newring->npoints); |
---|
674 | |
---|
675 | /* |
---|
676 | * Add ring to simplified ring array |
---|
677 | * (TODO: dinamic allocation of pts_per_ring) |
---|
678 | */ |
---|
679 | if ( ! nrings ) |
---|
680 | { |
---|
681 | newrings = palloc(sizeof(POINTARRAY *)); |
---|
682 | } |
---|
683 | else |
---|
684 | { |
---|
685 | newrings = repalloc(newrings, sizeof(POINTARRAY *)*(nrings+1)); |
---|
686 | } |
---|
687 | if ( ! newrings ) |
---|
688 | { |
---|
689 | elog(ERROR, "Out of virtual memory"); |
---|
690 | return NULL; |
---|
691 | } |
---|
692 | newrings[nrings++] = newring; |
---|
693 | } |
---|
694 | |
---|
695 | LWDEBUGF(3, "grid_polygon3d: simplified polygon with %d rings", nrings); |
---|
696 | |
---|
697 | if ( ! nrings ) return NULL; |
---|
698 | |
---|
699 | opoly = lwpoly_construct(poly->SRID, NULL, nrings, newrings); |
---|
700 | return opoly; |
---|
701 | } |
---|
702 | |
---|
703 | LWPOINT * |
---|
704 | lwpoint_grid(LWPOINT *point, gridspec *grid) |
---|
705 | { |
---|
706 | LWPOINT *opoint; |
---|
707 | POINTARRAY *opa; |
---|
708 | |
---|
709 | opa = ptarray_grid(point->point, grid); |
---|
710 | |
---|
711 | /* TODO: grid bounding box ? */ |
---|
712 | opoint = lwpoint_construct(point->SRID, NULL, opa); |
---|
713 | |
---|
714 | LWDEBUG(2, "lwpoint_grid called"); |
---|
715 | |
---|
716 | return opoint; |
---|
717 | } |
---|
718 | |
---|
719 | LWCOLLECTION * |
---|
720 | lwcollection_grid(LWCOLLECTION *coll, gridspec *grid) |
---|
721 | { |
---|
722 | unsigned int i; |
---|
723 | LWGEOM **geoms; |
---|
724 | unsigned int ngeoms=0; |
---|
725 | |
---|
726 | geoms = palloc(coll->ngeoms * sizeof(LWGEOM *)); |
---|
727 | |
---|
728 | for (i=0; i<coll->ngeoms; i++) |
---|
729 | { |
---|
730 | LWGEOM *g = lwgeom_grid(coll->geoms[i], grid); |
---|
731 | if ( g ) geoms[ngeoms++] = g; |
---|
732 | } |
---|
733 | |
---|
734 | if ( ! ngeoms ) return lwcollection_construct_empty(coll->SRID, 0, 0); |
---|
735 | |
---|
736 | return lwcollection_construct(TYPE_GETTYPE(coll->type), coll->SRID, |
---|
737 | NULL, ngeoms, geoms); |
---|
738 | } |
---|
739 | |
---|
740 | LWGEOM * |
---|
741 | lwgeom_grid(LWGEOM *lwgeom, gridspec *grid) |
---|
742 | { |
---|
743 | switch (TYPE_GETTYPE(lwgeom->type)) |
---|
744 | { |
---|
745 | case POINTTYPE: |
---|
746 | return (LWGEOM *)lwpoint_grid((LWPOINT *)lwgeom, grid); |
---|
747 | case LINETYPE: |
---|
748 | return (LWGEOM *)lwline_grid((LWLINE *)lwgeom, grid); |
---|
749 | case POLYGONTYPE: |
---|
750 | return (LWGEOM *)lwpoly_grid((LWPOLY *)lwgeom, grid); |
---|
751 | case MULTIPOINTTYPE: |
---|
752 | case MULTILINETYPE: |
---|
753 | case MULTIPOLYGONTYPE: |
---|
754 | case COLLECTIONTYPE: |
---|
755 | return (LWGEOM *)lwcollection_grid((LWCOLLECTION *)lwgeom, grid); |
---|
756 | default: |
---|
757 | elog(ERROR, "lwgeom_grid: Unsupported geometry type: %s", |
---|
758 | lwgeom_typename(TYPE_GETTYPE(lwgeom->type))); |
---|
759 | return NULL; |
---|
760 | } |
---|
761 | } |
---|
762 | |
---|
763 | PG_FUNCTION_INFO_V1(LWGEOM_snaptogrid); |
---|
764 | Datum LWGEOM_snaptogrid(PG_FUNCTION_ARGS) |
---|
765 | { |
---|
766 | Datum datum; |
---|
767 | PG_LWGEOM *in_geom; |
---|
768 | LWGEOM *in_lwgeom; |
---|
769 | PG_LWGEOM *out_geom = NULL; |
---|
770 | LWGEOM *out_lwgeom; |
---|
771 | gridspec grid; |
---|
772 | /* BOX3D box3d; */ |
---|
773 | |
---|
774 | if ( PG_ARGISNULL(0) ) PG_RETURN_NULL(); |
---|
775 | datum = PG_GETARG_DATUM(0); |
---|
776 | in_geom = (PG_LWGEOM *)PG_DETOAST_DATUM(datum); |
---|
777 | |
---|
778 | if ( PG_ARGISNULL(1) ) PG_RETURN_NULL(); |
---|
779 | grid.ipx = PG_GETARG_FLOAT8(1); |
---|
780 | |
---|
781 | if ( PG_ARGISNULL(2) ) PG_RETURN_NULL(); |
---|
782 | grid.ipy = PG_GETARG_FLOAT8(2); |
---|
783 | |
---|
784 | if ( PG_ARGISNULL(3) ) PG_RETURN_NULL(); |
---|
785 | grid.xsize = PG_GETARG_FLOAT8(3); |
---|
786 | |
---|
787 | if ( PG_ARGISNULL(4) ) PG_RETURN_NULL(); |
---|
788 | grid.ysize = PG_GETARG_FLOAT8(4); |
---|
789 | |
---|
790 | /* Do not support gridding Z and M values for now */ |
---|
791 | grid.ipz=grid.ipm=grid.zsize=grid.msize=0; |
---|
792 | |
---|
793 | /* Return input geometry if grid is null */ |
---|
794 | if ( grid_isNull(&grid) ) |
---|
795 | { |
---|
796 | PG_RETURN_POINTER(in_geom); |
---|
797 | } |
---|
798 | |
---|
799 | in_lwgeom = lwgeom_deserialize(SERIALIZED_FORM(in_geom)); |
---|
800 | |
---|
801 | POSTGIS_DEBUGF(3, "SnapToGrid got a %s", lwgeom_typename(TYPE_GETTYPE(in_lwgeom->type))); |
---|
802 | |
---|
803 | out_lwgeom = lwgeom_grid(in_lwgeom, &grid); |
---|
804 | if ( out_lwgeom == NULL ) PG_RETURN_NULL(); |
---|
805 | |
---|
806 | /* COMPUTE_BBOX TAINTING */ |
---|
807 | if ( in_lwgeom->bbox ) lwgeom_add_bbox(out_lwgeom); |
---|
808 | |
---|
809 | #if 0 |
---|
810 | /* |
---|
811 | * COMPUTE_BBOX WHEN SIMPLE |
---|
812 | * |
---|
813 | * WARNING: this is not SIMPLE, as snapping |
---|
814 | * an existing bbox to a grid does not |
---|
815 | * give the same result as computing a |
---|
816 | * new bounding box on the snapped coordinates. |
---|
817 | * |
---|
818 | * This bug has been fixed in postgis-1.1.2 |
---|
819 | */ |
---|
820 | if ( in_lwgeom->bbox ) |
---|
821 | { |
---|
822 | box2df_to_box3d_p(in_lwgeom->bbox, &box3d); |
---|
823 | |
---|
824 | box3d.xmin = rint((box3d.xmin - grid.ipx)/grid.xsize) |
---|
825 | * grid.xsize + grid.ipx; |
---|
826 | box3d.xmax = rint((box3d.xmax - grid.ipx)/grid.xsize) |
---|
827 | * grid.xsize + grid.ipx; |
---|
828 | box3d.ymin = rint((box3d.ymin - grid.ipy)/grid.ysize) |
---|
829 | * grid.ysize + grid.ipy; |
---|
830 | box3d.ymax = rint((box3d.ymax - grid.ipy)/grid.ysize) |
---|
831 | * grid.ysize + grid.ipy; |
---|
832 | |
---|
833 | out_lwgeom->bbox = box3d_to_box2df(&box3d); |
---|
834 | } |
---|
835 | #endif /* 0 */ |
---|
836 | |
---|
837 | POSTGIS_DEBUGF(3, "SnapToGrid made a %s", lwgeom_typename(TYPE_GETTYPE(out_lwgeom->type))); |
---|
838 | |
---|
839 | out_geom = pglwgeom_serialize(out_lwgeom); |
---|
840 | |
---|
841 | PG_RETURN_POINTER(out_geom); |
---|
842 | } |
---|
843 | |
---|
844 | PG_FUNCTION_INFO_V1(LWGEOM_snaptogrid_pointoff); |
---|
845 | Datum LWGEOM_snaptogrid_pointoff(PG_FUNCTION_ARGS) |
---|
846 | { |
---|
847 | Datum datum; |
---|
848 | PG_LWGEOM *in_geom, *in_point; |
---|
849 | LWGEOM *in_lwgeom; |
---|
850 | LWPOINT *in_lwpoint; |
---|
851 | PG_LWGEOM *out_geom = NULL; |
---|
852 | LWGEOM *out_lwgeom; |
---|
853 | gridspec grid; |
---|
854 | /* BOX3D box3d; */ |
---|
855 | POINT4D offsetpoint; |
---|
856 | |
---|
857 | if ( PG_ARGISNULL(0) ) PG_RETURN_NULL(); |
---|
858 | datum = PG_GETARG_DATUM(0); |
---|
859 | in_geom = (PG_LWGEOM *)PG_DETOAST_DATUM(datum); |
---|
860 | |
---|
861 | if ( PG_ARGISNULL(1) ) PG_RETURN_NULL(); |
---|
862 | datum = PG_GETARG_DATUM(1); |
---|
863 | in_point = (PG_LWGEOM *)PG_DETOAST_DATUM(datum); |
---|
864 | in_lwpoint = lwpoint_deserialize(SERIALIZED_FORM(in_point)); |
---|
865 | if ( in_lwpoint == NULL ) |
---|
866 | { |
---|
867 | lwerror("Offset geometry must be a point"); |
---|
868 | } |
---|
869 | |
---|
870 | if ( PG_ARGISNULL(2) ) PG_RETURN_NULL(); |
---|
871 | grid.xsize = PG_GETARG_FLOAT8(2); |
---|
872 | |
---|
873 | if ( PG_ARGISNULL(3) ) PG_RETURN_NULL(); |
---|
874 | grid.ysize = PG_GETARG_FLOAT8(3); |
---|
875 | |
---|
876 | if ( PG_ARGISNULL(4) ) PG_RETURN_NULL(); |
---|
877 | grid.zsize = PG_GETARG_FLOAT8(4); |
---|
878 | |
---|
879 | if ( PG_ARGISNULL(5) ) PG_RETURN_NULL(); |
---|
880 | grid.msize = PG_GETARG_FLOAT8(5); |
---|
881 | |
---|
882 | /* Take offsets from point geometry */ |
---|
883 | getPoint4d_p(in_lwpoint->point, 0, &offsetpoint); |
---|
884 | grid.ipx = offsetpoint.x; |
---|
885 | grid.ipy = offsetpoint.y; |
---|
886 | if (TYPE_HASZ(in_lwpoint->type) ) grid.ipz = offsetpoint.z; |
---|
887 | else grid.ipz=0; |
---|
888 | if (TYPE_HASM(in_lwpoint->type) ) grid.ipm = offsetpoint.m; |
---|
889 | else grid.ipm=0; |
---|
890 | |
---|
891 | #if POSTGIS_DEBUG_LEVEL >= 4 |
---|
892 | grid_print(&grid); |
---|
893 | #endif |
---|
894 | |
---|
895 | /* Return input geometry if grid is null */ |
---|
896 | if ( grid_isNull(&grid) ) |
---|
897 | { |
---|
898 | PG_RETURN_POINTER(in_geom); |
---|
899 | } |
---|
900 | |
---|
901 | in_lwgeom = lwgeom_deserialize(SERIALIZED_FORM(in_geom)); |
---|
902 | |
---|
903 | POSTGIS_DEBUGF(3, "SnapToGrid got a %s", lwgeom_typename(TYPE_GETTYPE(in_lwgeom->type))); |
---|
904 | |
---|
905 | out_lwgeom = lwgeom_grid(in_lwgeom, &grid); |
---|
906 | if ( out_lwgeom == NULL ) PG_RETURN_NULL(); |
---|
907 | |
---|
908 | /* COMPUTE_BBOX TAINTING */ |
---|
909 | if ( in_lwgeom->bbox ) lwgeom_add_bbox(out_lwgeom); |
---|
910 | |
---|
911 | #if 0 |
---|
912 | /* |
---|
913 | * COMPUTE_BBOX WHEN SIMPLE |
---|
914 | * |
---|
915 | * WARNING: this is not SIMPLE, as snapping |
---|
916 | * an existing bbox to a grid does not |
---|
917 | * give the same result as computing a |
---|
918 | * new bounding box on the snapped coordinates. |
---|
919 | * |
---|
920 | * This bug has been fixed in postgis-1.1.2 |
---|
921 | */ |
---|
922 | if ( in_lwgeom->bbox ) |
---|
923 | { |
---|
924 | box2df_to_box3d_p(in_lwgeom->bbox, &box3d); |
---|
925 | |
---|
926 | box3d.xmin = rint((box3d.xmin - grid.ipx)/grid.xsize) |
---|
927 | * grid.xsize + grid.ipx; |
---|
928 | box3d.xmax = rint((box3d.xmax - grid.ipx)/grid.xsize) |
---|
929 | * grid.xsize + grid.ipx; |
---|
930 | box3d.ymin = rint((box3d.ymin - grid.ipy)/grid.ysize) |
---|
931 | * grid.ysize + grid.ipy; |
---|
932 | box3d.ymax = rint((box3d.ymax - grid.ipy)/grid.ysize) |
---|
933 | * grid.ysize + grid.ipy; |
---|
934 | |
---|
935 | out_lwgeom->bbox = box3d_to_box2df(&box3d); |
---|
936 | } |
---|
937 | #endif /* 0 */ |
---|
938 | |
---|
939 | POSTGIS_DEBUGF(3, "SnapToGrid made a %s", lwgeom_typename(TYPE_GETTYPE(out_lwgeom->type))); |
---|
940 | |
---|
941 | out_geom = pglwgeom_serialize(out_lwgeom); |
---|
942 | |
---|
943 | PG_RETURN_POINTER(out_geom); |
---|
944 | } |
---|
945 | |
---|
946 | |
---|
947 | /* |
---|
948 | ** crossingDirection(line1, line2) |
---|
949 | ** |
---|
950 | ** Determines crossing direction of line2 relative to line1. |
---|
951 | ** Only accepts LINESTRING ass parameters! |
---|
952 | */ |
---|
953 | PG_FUNCTION_INFO_V1(ST_LineCrossingDirection); |
---|
954 | Datum ST_LineCrossingDirection(PG_FUNCTION_ARGS) |
---|
955 | { |
---|
956 | int type1, type2, rv; |
---|
957 | BOX2DFLOAT4 box1, box2; |
---|
958 | LWLINE *l1 = NULL; |
---|
959 | LWLINE *l2 = NULL; |
---|
960 | PG_LWGEOM *geom1 = (PG_LWGEOM *)PG_DETOAST_DATUM(PG_GETARG_DATUM(0)); |
---|
961 | PG_LWGEOM *geom2 = (PG_LWGEOM *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1)); |
---|
962 | |
---|
963 | errorIfSRIDMismatch(pglwgeom_getSRID(geom1), pglwgeom_getSRID(geom2)); |
---|
964 | |
---|
965 | /* |
---|
966 | ** If the bounding boxes don't interact, then there can't be any |
---|
967 | ** crossing, return right away. |
---|
968 | */ |
---|
969 | if ( getbox2d_p(SERIALIZED_FORM(geom1), &box1) && |
---|
970 | getbox2d_p(SERIALIZED_FORM(geom2), &box2) ) |
---|
971 | { |
---|
972 | if ( ( box2.xmax < box1.xmin ) || ( box2.xmin > box1.xmax ) || |
---|
973 | ( box2.ymax < box1.ymin ) || ( box2.ymin > box1.ymax ) ) |
---|
974 | { |
---|
975 | PG_RETURN_INT32(LINE_NO_CROSS); |
---|
976 | } |
---|
977 | } |
---|
978 | |
---|
979 | type1 = lwgeom_getType((uchar)SERIALIZED_FORM(geom1)[0]); |
---|
980 | type2 = lwgeom_getType((uchar)SERIALIZED_FORM(geom2)[0]); |
---|
981 | |
---|
982 | if ( type1 != LINETYPE || type2 != LINETYPE ) |
---|
983 | { |
---|
984 | elog(ERROR,"This function only accepts LINESTRING as arguments."); |
---|
985 | PG_RETURN_NULL(); |
---|
986 | } |
---|
987 | |
---|
988 | l1 = lwline_deserialize(SERIALIZED_FORM(geom1)); |
---|
989 | l2 = lwline_deserialize(SERIALIZED_FORM(geom2)); |
---|
990 | |
---|
991 | rv = lwline_crossing_direction(l1, l2); |
---|
992 | |
---|
993 | PG_FREE_IF_COPY(geom1, 0); |
---|
994 | PG_FREE_IF_COPY(geom2, 0); |
---|
995 | |
---|
996 | PG_RETURN_INT32(rv); |
---|
997 | |
---|
998 | } |
---|
999 | |
---|
1000 | PG_FUNCTION_INFO_V1(ST_LocateBetweenElevations); |
---|
1001 | Datum ST_LocateBetweenElevations(PG_FUNCTION_ARGS) |
---|
1002 | { |
---|
1003 | PG_LWGEOM *geom_in = (PG_LWGEOM *)PG_DETOAST_DATUM(PG_GETARG_DATUM(0)); |
---|
1004 | double from = PG_GETARG_FLOAT8(1); |
---|
1005 | double to = PG_GETARG_FLOAT8(2); |
---|
1006 | LWCOLLECTION *geom_out = NULL; |
---|
1007 | LWGEOM *line_in = NULL; |
---|
1008 | uchar type = (uchar)SERIALIZED_FORM(geom_in)[0]; |
---|
1009 | char geomtype = TYPE_GETTYPE(type); |
---|
1010 | char hasz = TYPE_HASZ(type); |
---|
1011 | static int ordinate = 2; /* Z */ |
---|
1012 | |
---|
1013 | if ( ! ( geomtype == LINETYPE || geomtype == MULTILINETYPE ) ) |
---|
1014 | { |
---|
1015 | elog(ERROR,"This function only accepts LINESTRING or MULTILINESTRING as arguments."); |
---|
1016 | PG_RETURN_NULL(); |
---|
1017 | } |
---|
1018 | |
---|
1019 | if ( ! hasz ) |
---|
1020 | { |
---|
1021 | elog(ERROR,"This function only accepts LINESTRING or MULTILINESTRING with Z values as arguments."); |
---|
1022 | PG_RETURN_NULL(); |
---|
1023 | } |
---|
1024 | |
---|
1025 | line_in = lwgeom_deserialize(SERIALIZED_FORM(geom_in)); |
---|
1026 | if ( geomtype == LINETYPE ) |
---|
1027 | { |
---|
1028 | geom_out = lwline_clip_to_ordinate_range((LWLINE*)line_in, ordinate, from, to); |
---|
1029 | } |
---|
1030 | else if ( geomtype == MULTILINETYPE ) |
---|
1031 | { |
---|
1032 | geom_out = lwmline_clip_to_ordinate_range((LWMLINE*)line_in, ordinate, from, to); |
---|
1033 | } |
---|
1034 | lwgeom_free(line_in); |
---|
1035 | |
---|
1036 | if ( ! geom_out ) |
---|
1037 | { |
---|
1038 | elog(ERROR,"The lwline_clip_to_ordinate_range returned null."); |
---|
1039 | PG_RETURN_NULL(); |
---|
1040 | } |
---|
1041 | |
---|
1042 | PG_FREE_IF_COPY(geom_in, 0); |
---|
1043 | PG_RETURN_POINTER(pglwgeom_serialize((LWGEOM*)geom_out)); |
---|
1044 | } |
---|
1045 | |
---|
1046 | /*********************************************************************** |
---|
1047 | * --strk@keybit.net |
---|
1048 | ***********************************************************************/ |
---|
1049 | |
---|
1050 | Datum LWGEOM_line_substring(PG_FUNCTION_ARGS); |
---|
1051 | |
---|
1052 | PG_FUNCTION_INFO_V1(LWGEOM_line_substring); |
---|
1053 | Datum LWGEOM_line_substring(PG_FUNCTION_ARGS) |
---|
1054 | { |
---|
1055 | PG_LWGEOM *geom = (PG_LWGEOM *)PG_DETOAST_DATUM(PG_GETARG_DATUM(0)); |
---|
1056 | double from = PG_GETARG_FLOAT8(1); |
---|
1057 | double to = PG_GETARG_FLOAT8(2); |
---|
1058 | LWLINE *iline; |
---|
1059 | LWGEOM *olwgeom; |
---|
1060 | POINTARRAY *ipa, *opa; |
---|
1061 | PG_LWGEOM *ret; |
---|
1062 | |
---|
1063 | if ( from < 0 || from > 1 ) |
---|
1064 | { |
---|
1065 | elog(ERROR,"line_interpolate_point: 2nd arg isnt within [0,1]"); |
---|
1066 | PG_RETURN_NULL(); |
---|
1067 | } |
---|
1068 | |
---|
1069 | if ( to < 0 || to > 1 ) |
---|
1070 | { |
---|
1071 | elog(ERROR,"line_interpolate_point: 3rd arg isnt within [0,1]"); |
---|
1072 | PG_RETURN_NULL(); |
---|
1073 | } |
---|
1074 | |
---|
1075 | if ( from > to ) |
---|
1076 | { |
---|
1077 | elog(ERROR, "2nd arg must be smaller then 3rd arg"); |
---|
1078 | PG_RETURN_NULL(); |
---|
1079 | } |
---|
1080 | |
---|
1081 | if ( lwgeom_getType(geom->type) != LINETYPE ) |
---|
1082 | { |
---|
1083 | elog(ERROR,"line_interpolate_point: 1st arg isnt a line"); |
---|
1084 | PG_RETURN_NULL(); |
---|
1085 | } |
---|
1086 | |
---|
1087 | iline = lwline_deserialize(SERIALIZED_FORM(geom)); |
---|
1088 | ipa = iline->points; |
---|
1089 | |
---|
1090 | opa = ptarray_substring(ipa, from, to); |
---|
1091 | |
---|
1092 | if ( opa->npoints == 1 ) /* Point returned */ |
---|
1093 | olwgeom = (LWGEOM *)lwpoint_construct(iline->SRID, NULL, opa); |
---|
1094 | else |
---|
1095 | olwgeom = (LWGEOM *)lwline_construct(iline->SRID, NULL, opa); |
---|
1096 | |
---|
1097 | ret = pglwgeom_serialize(olwgeom); |
---|
1098 | PG_FREE_IF_COPY(geom, 0); |
---|
1099 | lwgeom_release(olwgeom); |
---|
1100 | PG_RETURN_POINTER(ret); |
---|
1101 | } |
---|
1102 | |
---|
1103 | Datum LWGEOM_line_locate_point(PG_FUNCTION_ARGS); |
---|
1104 | |
---|
1105 | PG_FUNCTION_INFO_V1(LWGEOM_line_locate_point); |
---|
1106 | Datum LWGEOM_line_locate_point(PG_FUNCTION_ARGS) |
---|
1107 | { |
---|
1108 | PG_LWGEOM *geom1 = (PG_LWGEOM *)PG_DETOAST_DATUM(PG_GETARG_DATUM(0)); |
---|
1109 | PG_LWGEOM *geom2 = (PG_LWGEOM *)PG_DETOAST_DATUM(PG_GETARG_DATUM(1)); |
---|
1110 | LWLINE *lwline; |
---|
1111 | LWPOINT *lwpoint; |
---|
1112 | POINTARRAY *pa; |
---|
1113 | POINT2D p; |
---|
1114 | double ret; |
---|
1115 | |
---|
1116 | if ( lwgeom_getType(geom1->type) != LINETYPE ) |
---|
1117 | { |
---|
1118 | elog(ERROR,"line_locate_point: 1st arg isnt a line"); |
---|
1119 | PG_RETURN_NULL(); |
---|
1120 | } |
---|
1121 | if ( lwgeom_getType(geom2->type) != POINTTYPE ) |
---|
1122 | { |
---|
1123 | elog(ERROR,"line_locate_point: 2st arg isnt a point"); |
---|
1124 | PG_RETURN_NULL(); |
---|
1125 | } |
---|
1126 | if ( pglwgeom_getSRID(geom1) != pglwgeom_getSRID(geom2) ) |
---|
1127 | { |
---|
1128 | elog(ERROR, "Operation on two geometries with different SRIDs"); |
---|
1129 | PG_RETURN_NULL(); |
---|
1130 | } |
---|
1131 | |
---|
1132 | lwline = lwline_deserialize(SERIALIZED_FORM(geom1)); |
---|
1133 | lwpoint = lwpoint_deserialize(SERIALIZED_FORM(geom2)); |
---|
1134 | |
---|
1135 | pa = lwline->points; |
---|
1136 | lwpoint_getPoint2d_p(lwpoint, &p); |
---|
1137 | |
---|
1138 | ret = ptarray_locate_point(pa, &p); |
---|
1139 | |
---|
1140 | PG_RETURN_FLOAT8(ret); |
---|
1141 | } |
---|
1142 | |
---|
1143 | /******************************************************************************* |
---|
1144 | * The following is based on the "Fast Winding Number Inclusion of a Point |
---|
1145 | * in a Polygon" algorithm by Dan Sunday. |
---|
1146 | * http://softsurfer.com/Archive/algorithm_0103/algorithm_0103.htm#Winding%20Number |
---|
1147 | ******************************************************************************/ |
---|
1148 | |
---|
1149 | /* |
---|
1150 | * returns: >0 for a point to the left of the segment, |
---|
1151 | * <0 for a point to the right of the segment, |
---|
1152 | * 0 for a point on the segment |
---|
1153 | */ |
---|
1154 | double determineSide(POINT2D *seg1, POINT2D *seg2, POINT2D *point) |
---|
1155 | { |
---|
1156 | return ((seg2->x-seg1->x)*(point->y-seg1->y)-(point->x-seg1->x)*(seg2->y-seg1->y)); |
---|
1157 | } |
---|
1158 | |
---|
1159 | /* |
---|
1160 | * This function doesn't test that the point falls on the line defined by |
---|
1161 | * the two points. It assumes that that has already been determined |
---|
1162 | * by having determineSide return within the tolerance. It simply checks |
---|
1163 | * that if the point is on the line, it is within the endpoints. |
---|
1164 | * |
---|
1165 | * returns: 1 if the point is not outside the bounds of the segment |
---|
1166 | * 0 if it is |
---|
1167 | */ |
---|
1168 | int isOnSegment(POINT2D *seg1, POINT2D *seg2, POINT2D *point) |
---|
1169 | { |
---|
1170 | double maxX; |
---|
1171 | double maxY; |
---|
1172 | double minX; |
---|
1173 | double minY; |
---|
1174 | |
---|
1175 | if (seg1->x > seg2->x) |
---|
1176 | { |
---|
1177 | maxX = seg1->x; |
---|
1178 | minX = seg2->x; |
---|
1179 | } |
---|
1180 | else |
---|
1181 | { |
---|
1182 | maxX = seg2->x; |
---|
1183 | minX = seg1->x; |
---|
1184 | } |
---|
1185 | if (seg1->y > seg2->y) |
---|
1186 | { |
---|
1187 | maxY = seg1->y; |
---|
1188 | minY = seg2->y; |
---|
1189 | } |
---|
1190 | else |
---|
1191 | { |
---|
1192 | maxY = seg2->y; |
---|
1193 | minY = seg1->y; |
---|
1194 | } |
---|
1195 | |
---|
1196 | LWDEBUGF(3, "maxX minX/maxY minY: %.8f %.8f/%.8f %.8f", maxX, minX, maxY, minY); |
---|
1197 | |
---|
1198 | if (maxX < point->x || minX > point->x) |
---|
1199 | { |
---|
1200 | LWDEBUGF(3, "X value %.8f falls outside the range %.8f-%.8f", point->x, minX, maxX); |
---|
1201 | |
---|
1202 | return 0; |
---|
1203 | } |
---|
1204 | else if (maxY < point->y || minY > point->y) |
---|
1205 | { |
---|
1206 | LWDEBUGF(3, "Y value %.8f falls outside the range %.8f-%.8f", point->y, minY, maxY); |
---|
1207 | |
---|
1208 | return 0; |
---|
1209 | } |
---|
1210 | return 1; |
---|
1211 | } |
---|
1212 | |
---|
1213 | /* |
---|
1214 | * return -1 iff point is outside ring pts |
---|
1215 | * return 1 iff point is inside ring pts |
---|
1216 | * return 0 iff point is on ring pts |
---|
1217 | */ |
---|
1218 | int point_in_ring_rtree(RTREE_NODE *root, POINT2D *point) |
---|
1219 | { |
---|
1220 | int wn = 0; |
---|
1221 | int i; |
---|
1222 | double side; |
---|
1223 | POINT2D seg1; |
---|
1224 | POINT2D seg2; |
---|
1225 | LWMLINE *lines; |
---|
1226 | |
---|
1227 | LWDEBUG(2, "point_in_ring called."); |
---|
1228 | |
---|
1229 | lines = findLineSegments(root, point->y); |
---|
1230 | if (!lines) |
---|
1231 | return -1; |
---|
1232 | |
---|
1233 | for (i=0; i<lines->ngeoms; i++) |
---|
1234 | { |
---|
1235 | getPoint2d_p(lines->geoms[i]->points, 0, &seg1); |
---|
1236 | getPoint2d_p(lines->geoms[i]->points, 1, &seg2); |
---|
1237 | |
---|
1238 | |
---|
1239 | side = determineSide(&seg1, &seg2, point); |
---|
1240 | |
---|
1241 | LWDEBUGF(3, "segment: (%.8f, %.8f),(%.8f, %.8f)", seg1.x, seg1.y, seg2.x, seg2.y); |
---|
1242 | LWDEBUGF(3, "side result: %.8f", side); |
---|
1243 | LWDEBUGF(3, "counterclockwise wrap %d, clockwise wrap %d", FP_CONTAINS_BOTTOM(seg1.y,point->y,seg2.y), FP_CONTAINS_BOTTOM(seg2.y,point->y,seg1.y)); |
---|
1244 | |
---|
1245 | /* zero length segments are ignored. */ |
---|
1246 | if (((seg2.x-seg1.x)*(seg2.x-seg1.x)+(seg2.y-seg1.y)*(seg2.y-seg1.y)) < 1e-12*1e-12) |
---|
1247 | { |
---|
1248 | LWDEBUG(3, "segment is zero length... ignoring."); |
---|
1249 | |
---|
1250 | continue; |
---|
1251 | } |
---|
1252 | |
---|
1253 | /* a point on the boundary of a ring is not contained. */ |
---|
1254 | if (fabs(side) < 1e-12) |
---|
1255 | { |
---|
1256 | if (isOnSegment(&seg1, &seg2, point) == 1) |
---|
1257 | { |
---|
1258 | LWDEBUGF(3, "point on ring boundary between points %d, %d", i, i+1); |
---|
1259 | |
---|
1260 | return 0; |
---|
1261 | } |
---|
1262 | } |
---|
1263 | /* |
---|
1264 | * If the point is to the left of the line, and it's rising, |
---|
1265 | * then the line is to the right of the point and |
---|
1266 | * circling counter-clockwise, so incremement. |
---|
1267 | */ |
---|
1268 | else if (FP_CONTAINS_BOTTOM(seg1.y,point->y,seg2.y) && side>0) |
---|
1269 | { |
---|
1270 | LWDEBUG(3, "incrementing winding number."); |
---|
1271 | |
---|
1272 | ++wn; |
---|
1273 | } |
---|
1274 | /* |
---|
1275 | * If the point is to the right of the line, and it's falling, |
---|
1276 | * then the line is to the right of the point and circling |
---|
1277 | * clockwise, so decrement. |
---|
1278 | */ |
---|
1279 | else if (FP_CONTAINS_BOTTOM(seg2.y,point->y,seg1.y) && side<0) |
---|
1280 | { |
---|
1281 | LWDEBUG(3, "decrementing winding number."); |
---|
1282 | |
---|
1283 | --wn; |
---|
1284 | } |
---|
1285 | } |
---|
1286 | |
---|
1287 | LWDEBUGF(3, "winding number %d", wn); |
---|
1288 | |
---|
1289 | if (wn == 0) |
---|
1290 | return -1; |
---|
1291 | return 1; |
---|
1292 | } |
---|
1293 | |
---|
1294 | |
---|
1295 | /* |
---|
1296 | * return -1 iff point is outside ring pts |
---|
1297 | * return 1 iff point is inside ring pts |
---|
1298 | * return 0 iff point is on ring pts |
---|
1299 | */ |
---|
1300 | int point_in_ring(POINTARRAY *pts, POINT2D *point) |
---|
1301 | { |
---|
1302 | int wn = 0; |
---|
1303 | int i; |
---|
1304 | double side; |
---|
1305 | POINT2D seg1; |
---|
1306 | POINT2D seg2; |
---|
1307 | |
---|
1308 | LWDEBUG(2, "point_in_ring called."); |
---|
1309 | |
---|
1310 | |
---|
1311 | for (i=0; i<pts->npoints-1; i++) |
---|
1312 | { |
---|
1313 | getPoint2d_p(pts, i, &seg1); |
---|
1314 | getPoint2d_p(pts, i+1, &seg2); |
---|
1315 | |
---|
1316 | |
---|
1317 | side = determineSide(&seg1, &seg2, point); |
---|
1318 | |
---|
1319 | LWDEBUGF(3, "segment: (%.8f, %.8f),(%.8f, %.8f)", seg1.x, seg1.y, seg2.x, seg2.y); |
---|
1320 | LWDEBUGF(3, "side result: %.8f", side); |
---|
1321 | LWDEBUGF(3, "counterclockwise wrap %d, clockwise wrap %d", FP_CONTAINS_BOTTOM(seg1.y,point->y,seg2.y), FP_CONTAINS_BOTTOM(seg2.y,point->y,seg1.y)); |
---|
1322 | |
---|
1323 | /* zero length segments are ignored. */ |
---|
1324 | if (((seg2.x-seg1.x)*(seg2.x-seg1.x)+(seg2.y-seg1.y)*(seg2.y-seg1.y)) < 1e-12*1e-12) |
---|
1325 | { |
---|
1326 | LWDEBUG(3, "segment is zero length... ignoring."); |
---|
1327 | |
---|
1328 | continue; |
---|
1329 | } |
---|
1330 | |
---|
1331 | /* a point on the boundary of a ring is not contained. */ |
---|
1332 | if (fabs(side) < 1e-12) |
---|
1333 | { |
---|
1334 | if (isOnSegment(&seg1, &seg2, point) == 1) |
---|
1335 | { |
---|
1336 | LWDEBUGF(3, "point on ring boundary between points %d, %d", i, i+1); |
---|
1337 | |
---|
1338 | return 0; |
---|
1339 | } |
---|
1340 | } |
---|
1341 | /* |
---|
1342 | * If the point is to the left of the line, and it's rising, |
---|
1343 | * then the line is to the right of the point and |
---|
1344 | * circling counter-clockwise, so incremement. |
---|
1345 | */ |
---|
1346 | else if (FP_CONTAINS_BOTTOM(seg1.y,point->y,seg2.y) && side>0) |
---|
1347 | { |
---|
1348 | LWDEBUG(3, "incrementing winding number."); |
---|
1349 | |
---|
1350 | ++wn; |
---|
1351 | } |
---|
1352 | /* |
---|
1353 | * If the point is to the right of the line, and it's falling, |
---|
1354 | * then the line is to the right of the point and circling |
---|
1355 | * clockwise, so decrement. |
---|
1356 | */ |
---|
1357 | else if (FP_CONTAINS_BOTTOM(seg2.y,point->y,seg1.y) && side<0) |
---|
1358 | { |
---|
1359 | LWDEBUG(3, "decrementing winding number."); |
---|
1360 | |
---|
1361 | --wn; |
---|
1362 | } |
---|
1363 | } |
---|
1364 | |
---|
1365 | LWDEBUGF(3, "winding number %d", wn); |
---|
1366 | |
---|
1367 | if (wn == 0) |
---|
1368 | return -1; |
---|
1369 | return 1; |
---|
1370 | } |
---|
1371 | |
---|
1372 | /* |
---|
1373 | * return 0 iff point outside polygon or on boundary |
---|
1374 | * return 1 iff point inside polygon |
---|
1375 | */ |
---|
1376 | int point_in_polygon_rtree(RTREE_NODE **root, int ringCount, LWPOINT *point) |
---|
1377 | { |
---|
1378 | int i; |
---|
1379 | POINT2D pt; |
---|
1380 | |
---|
1381 | LWDEBUGF(2, "point_in_polygon called for %p %d %p.", root, ringCount, point); |
---|
1382 | |
---|
1383 | getPoint2d_p(point->point, 0, &pt); |
---|
1384 | /* assume bbox short-circuit has already been attempted */ |
---|
1385 | |
---|
1386 | if (point_in_ring_rtree(root[0], &pt) != 1) |
---|
1387 | { |
---|
1388 | LWDEBUG(3, "point_in_polygon_rtree: outside exterior ring."); |
---|
1389 | |
---|
1390 | return 0; |
---|
1391 | } |
---|
1392 | |
---|
1393 | for (i=1; i<ringCount; i++) |
---|
1394 | { |
---|
1395 | if (point_in_ring_rtree(root[i], &pt) != -1) |
---|
1396 | { |
---|
1397 | LWDEBUGF(3, "point_in_polygon_rtree: within hole %d.", i); |
---|
1398 | |
---|
1399 | return 0; |
---|
1400 | } |
---|
1401 | } |
---|
1402 | return 1; |
---|
1403 | } |
---|
1404 | |
---|
1405 | /* |
---|
1406 | * return -1 if point outside polygon |
---|
1407 | * return 0 if point on boundary |
---|
1408 | * return 1 if point inside polygon |
---|
1409 | * |
---|
1410 | * Expected **root order is all the exterior rings first, then all the holes |
---|
1411 | * |
---|
1412 | * TODO: this could be made slightly more efficient by ordering the rings in |
---|
1413 | * EIIIEIIIEIEI order (exterior/interior) and including list of exterior ring |
---|
1414 | * positions on the cache object. |
---|
1415 | */ |
---|
1416 | int point_in_multipolygon_rtree(RTREE_NODE **root, int polyCount, int ringCount, LWPOINT *point) |
---|
1417 | { |
---|
1418 | int i; |
---|
1419 | POINT2D pt; |
---|
1420 | int result = -1; |
---|
1421 | |
---|
1422 | LWDEBUGF(2, "point_in_multipolygon_rtree called for %p %d %d %p.", root, polyCount, ringCount, point); |
---|
1423 | |
---|
1424 | getPoint2d_p(point->point, 0, &pt); |
---|
1425 | /* assume bbox short-circuit has already been attempted */ |
---|
1426 | |
---|
1427 | /* is the point inside (not outside) any of the exterior rings? */ |
---|
1428 | for ( i = 0; i < polyCount; i++ ) |
---|
1429 | { |
---|
1430 | int in_ring = point_in_ring_rtree(root[i], &pt); |
---|
1431 | LWDEBUGF(4, "point_in_multipolygon_rtree: exterior ring (%d), point_in_ring returned %d", i, in_ring); |
---|
1432 | if ( in_ring != -1 ) /* not outside this ring */ |
---|
1433 | { |
---|
1434 | LWDEBUG(3, "point_in_multipolygon_rtree: inside exterior ring."); |
---|
1435 | result = in_ring; |
---|
1436 | break; |
---|
1437 | } |
---|
1438 | } |
---|
1439 | |
---|
1440 | if ( result == -1 ) /* strictly outside all rings */ |
---|
1441 | return result; |
---|
1442 | |
---|
1443 | /* ok, it's in a ring, but if it's in a hole it's still outside */ |
---|
1444 | for ( i = polyCount; i < ringCount; i++ ) |
---|
1445 | { |
---|
1446 | int in_ring = point_in_ring_rtree(root[i], &pt); |
---|
1447 | LWDEBUGF(4, "point_in_multipolygon_rtree: hole (%d), point_in_ring returned %d", i, in_ring); |
---|
1448 | if ( in_ring == 1 ) /* completely inside hole */ |
---|
1449 | { |
---|
1450 | LWDEBUGF(3, "point_in_multipolygon_rtree: within hole %d.", i); |
---|
1451 | return -1; |
---|
1452 | } |
---|
1453 | if ( in_ring == 0 ) /* on the boundary of a hole */ |
---|
1454 | { |
---|
1455 | result = 0; |
---|
1456 | } |
---|
1457 | } |
---|
1458 | return result; /* -1 = outside, 0 = boundary, 1 = inside */ |
---|
1459 | |
---|
1460 | } |
---|
1461 | |
---|
1462 | /* |
---|
1463 | * return -1 iff point outside polygon |
---|
1464 | * return 0 iff point on boundary |
---|
1465 | * return 1 iff point inside polygon |
---|
1466 | */ |
---|
1467 | int point_in_polygon(LWPOLY *polygon, LWPOINT *point) |
---|
1468 | { |
---|
1469 | int i, result, in_ring; |
---|
1470 | POINTARRAY *ring; |
---|
1471 | POINT2D pt; |
---|
1472 | |
---|
1473 | LWDEBUG(2, "point_in_polygon called."); |
---|
1474 | |
---|
1475 | getPoint2d_p(point->point, 0, &pt); |
---|
1476 | /* assume bbox short-circuit has already been attempted */ |
---|
1477 | |
---|
1478 | ring = polygon->rings[0]; |
---|
1479 | in_ring = point_in_ring(polygon->rings[0], &pt); |
---|
1480 | if ( in_ring == -1) /* outside the exterior ring */ |
---|
1481 | { |
---|
1482 | LWDEBUG(3, "point_in_polygon: outside exterior ring."); |
---|
1483 | return -1; |
---|
1484 | } |
---|
1485 | result = in_ring; |
---|
1486 | |
---|
1487 | for (i=1; i<polygon->nrings; i++) |
---|
1488 | { |
---|
1489 | ring = polygon->rings[i]; |
---|
1490 | in_ring = point_in_ring(polygon->rings[i], &pt); |
---|
1491 | if (in_ring == 1) /* inside a hole => outside the polygon */ |
---|
1492 | { |
---|
1493 | LWDEBUGF(3, "point_in_polygon: within hole %d.", i); |
---|
1494 | return -1; |
---|
1495 | } |
---|
1496 | if (in_ring == 0) /* on the edge of a hole */ |
---|
1497 | { |
---|
1498 | LWDEBUGF(3, "point_in_polygon: on edge of hole %d.", i); |
---|
1499 | return 0; |
---|
1500 | } |
---|
1501 | } |
---|
1502 | return result; /* -1 = outside, 0 = boundary, 1 = inside */ |
---|
1503 | } |
---|
1504 | |
---|
1505 | /* |
---|
1506 | * return -1 iff point outside multipolygon |
---|
1507 | * return 0 iff point on multipolygon boundary |
---|
1508 | * return 1 iff point inside multipolygon |
---|
1509 | */ |
---|
1510 | int point_in_multipolygon(LWMPOLY *mpolygon, LWPOINT *point) |
---|
1511 | { |
---|
1512 | int i, j, result, in_ring; |
---|
1513 | POINTARRAY *ring; |
---|
1514 | POINT2D pt; |
---|
1515 | |
---|
1516 | LWDEBUG(2, "point_in_polygon called."); |
---|
1517 | |
---|
1518 | getPoint2d_p(point->point, 0, &pt); |
---|
1519 | /* assume bbox short-circuit has already been attempted */ |
---|
1520 | |
---|
1521 | result = -1; |
---|
1522 | |
---|
1523 | for (j = 0; j < mpolygon->ngeoms; j++ ) |
---|
1524 | { |
---|
1525 | |
---|
1526 | LWPOLY *polygon = mpolygon->geoms[j]; |
---|
1527 | ring = polygon->rings[0]; |
---|
1528 | in_ring = point_in_ring(polygon->rings[0], &pt); |
---|
1529 | if ( in_ring == -1) /* outside the exterior ring */ |
---|
1530 | { |
---|
1531 | LWDEBUG(3, "point_in_polygon: outside exterior ring."); |
---|
1532 | continue; |
---|
1533 | } |
---|
1534 | if ( in_ring == 0 ) |
---|
1535 | { |
---|
1536 | return 0; |
---|
1537 | } |
---|
1538 | |
---|
1539 | result = in_ring; |
---|
1540 | |
---|
1541 | for (i=1; i<polygon->nrings; i++) |
---|
1542 | { |
---|
1543 | ring = polygon->rings[i]; |
---|
1544 | in_ring = point_in_ring(polygon->rings[i], &pt); |
---|
1545 | if (in_ring == 1) /* inside a hole => outside the polygon */ |
---|
1546 | { |
---|
1547 | LWDEBUGF(3, "point_in_polygon: within hole %d.", i); |
---|
1548 | result = -1; |
---|
1549 | break; |
---|
1550 | } |
---|
1551 | if (in_ring == 0) /* on the edge of a hole */ |
---|
1552 | { |
---|
1553 | LWDEBUGF(3, "point_in_polygon: on edge of hole %d.", i); |
---|
1554 | return 0; |
---|
1555 | } |
---|
1556 | } |
---|
1557 | if ( result != -1) |
---|
1558 | { |
---|
1559 | return result; |
---|
1560 | } |
---|
1561 | } |
---|
1562 | return result; |
---|
1563 | } |
---|
1564 | |
---|
1565 | |
---|
1566 | /******************************************************************************* |
---|
1567 | * End of "Fast Winding Number Inclusion of a Point in a Polygon" derivative. |
---|
1568 | ******************************************************************************/ |
---|
1569 | |
---|