Changes between Version 24 and Version 25 of PostGIS_Raster_SoC_Idea_2012/Distance_Analysis_Tools

Show
Ignore:
Timestamp:
06/17/12 15:37:55 (12 months ago)
Author:
qliu
Comment:

--

Legend:

Unmodified
Added
Removed
Modified
  • PostGIS_Raster_SoC_Idea_2012/Distance_Analysis_Tools

    v24 v25  
    108108<b>Comment from Mentor:</b> 
    109109<p> 
    110 I really think we want to avoid having to produce an intermediate raster of sources. PostGIS is strong on raster/vector interaction and I really don't see why someone would prefer to provide sources as raster. The sources should come from a table of point. Now this raise a certain number of issues: 
    111  
    112  -What if the table contains more than one point? 
    113  -What if some of those points are outside the raster extent? 
    114  -Another issue is: What if the raster I want to produce does not fit into the PostgreSQL maximum field size? 
    115  
    116 These are the kind or difficulties one encounters when working in a database. 
    117  
     110I really think we want to avoid having to produce an intermediate raster of sources. PostGIS is strong on raster/vector interaction and I really don't see why someone would prefer to provide sources as raster. The sources should come from a table of point. Now this raise a certain number of issues:</br> 
     111</br> 
     112 -What if the table contains more than one point?</br> 
     113 -What if some of those points are outside the raster extent?</br> 
     114 -Another issue is: What if the raster I want to produce does not fit into the PostgreSQL maximum field size?</br> 
     115</br> 
     116These are the kind or difficulties one encounters when working in a database.</br> 
     117</br> 
    118118Think about large tiled coverage, Delaunay triangulation,  aggregate functions and all the combinatory of "small/very large number of point" and "small/very large raster coverage". Ideally we want to provide a solution working for every limit cases. 
    119119</p>