Opened 17 years ago

Closed 15 years ago

#111 closed defect (fixed)

r.los fails with high values for max_dis parameter

Reported by: gsancho Owned by: grass-dev@…
Priority: major Milestone: 6.4.0
Component: Raster Version: svn-develbranch6
Keywords: wingrass r.los Cc: marco.pasetti@…
CPU: x86-32 Platform: MSWindows XP

Description

Hello.

I have a problem with the operation r.los in winGrass(native). I have been testing different maps and when a distance is greater than 80-100 pixels (map pixels) a system error is thrown.

To put an example, in spearfish data base and the elevation.dem map, grass fails from 2524m on up (with the height of the observer set to 1m)

The command would be: r.los input=elevation.dem output=los coordinate=599505,4921010 max_dis=2525

The error that is reported is a system error: "r.los.exe there are encountered to problem and needs to close"

Thanks and regards.

Attachments (1)

rlos.diff (397 bytes ) - added by neteler 16 years ago.
fix for compilation problem

Download all attachments as: .zip

Change History (37)

in reply to:  description ; comment:1 by 4everskiff, 16 years ago

Cc: marco.pasetti@… added

Replying to gsancho:

Hello.

I have a problem with the operation r.los in winGrass(native). I have been testing different maps and when a distance is greater than 80-100 pixels (map pixels) a system error is thrown.

To put an example, in spearfish data base and the elevation.dem map, grass fails from 2524m on up (with the height of the observer set to 1m)

The command would be: r.los input=elevation.dem output=los coordinate=599505,4921010 max_dis=2525

The error that is reported is a system error: "r.los.exe there are encountered to problem and needs to close"

Thanks and regards.

Hi,

I checked the command on WinGRASS-6.3.0RC6 (WinXP). It's the same for me. BTW, the error seems to be not related to WinGRASS, but to the map in use or to the module as cross-platform error (maybe related to the dimension of data to be processed?). For example, I launched the command on another raster dem map (with a resolution of 20m) with dist set to 3000, and it works fine, while it fails with 3001! Could someone test it also on linux or mac?

Thank you

Marco

comment:2 by mlennert, 16 years ago

I cannot confirm this on Debian GNU/Linux with recent svn, so it seems to be win-specific.

Moritz

comment:3 by 4everskiff, 16 years ago

Version: unspecified6.3.0 RCs

comment:4 by 4everskiff, 16 years ago

Summary: r.los error "r.los.exe there are encountered to problem and needs to close"r.los fails in WinGRASS with high values for max_dis parameter
Version: 6.3.0 RCs6.3.0

in reply to:  description comment:5 by marcopx, 16 years ago

I tested it on my new Vista build (on Windows Vista Home Premium).

The reported sample command line worked fine for me.

I also tried with other command inputs (but with the same input dem and coordinates) and always worked fine.

I'll wait positive feedbacks from XP to close the ticket.

Marco

in reply to:  1 comment:6 by aborruso, 16 years ago

Component: defaultRaster
CPU: x86-32
Platform: MSWindows XP

I tested it on winxp sp3, and it crashes.

This is my command: r.los input=DEM@andrea output=tr_vis coordinate=300877,4213602 obs_elev=1.75 max_dist=5000

I use GRASS 6.3.0 (2008) downloaded from: http://grass.osgeo.org/grass63/binary/mswindows/native/WinGRASS-6.3.0-4-Setup.exe

Andrea

comment:7 by neteler, 16 years ago

Version: 6.3.0svn-develbranch6

I have tried r.los with valgrind on Linux 64bit (GRASS 7):

# Spearfish60
g.region -dp
CMD="r.los in=elevation.dem output=tr_vis coordinate=599490,4920855 max_dist=10000"
valgrind --tool=memcheck --leak-check=yes --show-reachable=yes $CMD --o
...
Using maximum distance from the viewing point (meters): 10000.000000
==15765== Invalid read of size 8      
==15765==    at 0x403616: hidden_point_elimination (pts_elim.c:107) 
==15765==    by 0x403B0E: segment (segment.c:81)     
==15765==    by 0x402B41: main (main.c:330)   
==15765==  Address 0xb062d90 is 24 bytes inside a block of size 40 free'd  
==15765==    at 0x4C2006F: free (vg_replace_malloc.c:323)   
==15765==    by 0x503A4A9: G_free (alloc.c:129)      
==15765==    by 0x401D5B: delete (delete.c:39)
==15765==    by 0x40357E: hidden_point_elimination (pts_elim.c:166) 
==15765==    by 0x403B0E: segment (segment.c:81)     
==15765==    by 0x402B41: main (main.c:330)   
==15765==
==15765== Invalid read of size 1      
==15765==    at 0x4C21FC0: memcpy (mc_replace_strmem.c:402) 
==15765==    by 0x4E2619E: segment_get (get.c:49)    
==15765==    by 0x403885: find_inclination (pts_elim.c:291) 
==15765==    by 0x40336E: hidden_point_elimination (pts_elim.c:94)  
==15765==    by 0x403B0E: segment (segment.c:81)     
==15765==    by 0x402B41: main (main.c:330)   
==15765==  Address 0xafdcc77 is 1 bytes before a block of size 76,320 alloc'd     
==15765==    at 0x4C2136E: malloc (vg_replace_malloc.c:207) 
==15765==    by 0x503A34E: G__malloc (alloc.c:41)    
==15765==    by 0x4E26E71: segment_setup (setup.c:64)
==15765==    by 0x4E26431: segment_init (init.c:75)  
==15765==    by 0x40264E: main (main.c:257)   
...
==15765== Invalid read of size 1      
==15765==    at 0x4C21FDC: memcpy (mc_replace_strmem.c:402) 
==15765==    by 0x4E2619E: segment_get (get.c:49)    
==15765==    by 0x403885: find_inclination (pts_elim.c:291) 
==15765==    by 0x4033B2: hidden_point_elimination (pts_elim.c:99)  
==15765==    by 0x403B0E: segment (segment.c:81)     
==15765==    by 0x402B41: main (main.c:330)   
==15765==  Address 0xafdcc74 is 4 bytes before a block of size 76,320 alloc'd     
==15765==    at 0x4C2136E: malloc (vg_replace_malloc.c:207) 
==15765==    by 0x503A34E: G__malloc (alloc.c:41)    
==15765==    by 0x4E26E71: segment_setup (setup.c:64)
==15765==    by 0x4E26431: segment_init (init.c:75)  
==15765==    by 0x40264E: main (main.c:257)   
 100%    
==15765==
==15765== Conditional jump or move depends on uninitialised value(s)
==15765==    at 0x5498B4E: (within /lib64/libz.so.1.2.3)    
==15765==    by 0x549949C: (within /lib64/libz.so.1.2.3)    
==15765==    by 0x549A06F: deflate (in /lib64/libz.so.1.2.3)
==15765==    by 0x504A97C: G_zlib_compress (flate.c:339)    
==15765==    by 0x504A650: G_zlib_write (flate.c:213)
==15765==    by 0x5064BC9: write_data_compressed (put_row.c:217)    
==15765==    by 0x5064FC9: put_fp_data (put_row.c:333)      
==15765==    by 0x50659AB: put_raster_data (put_row.c:633)  
==15765==    by 0x50662E0: put_raster_row (put_row.c:848)   
==15765==    by 0x5064907: G_put_raster_row (put_row.c:144) 
==15765==    by 0x402D5E: main (main.c:381)   
==15765==
==15765== Conditional jump or move depends on uninitialised value(s)
==15765==    at 0x5498B5B: (within /lib64/libz.so.1.2.3)    
==15765==    by 0x549949C: (within /lib64/libz.so.1.2.3)    
==15765==    by 0x549A06F: deflate (in /lib64/libz.so.1.2.3)
==15765==    by 0x504A97C: G_zlib_compress (flate.c:339)    
==15765==    by 0x504A650: G_zlib_write (flate.c:213)
...
==15765==
==15765== ERROR SUMMARY: 284197 errors from 21 contexts (suppressed: 3 from 1)    
==15765== malloc/free: in use at exit: 448,984 bytes in 10,702 blocks.     
==15765== malloc/free: 291,268 allocs, 280,566 frees, 142,519,073 bytes allocated.
==15765== For counts of detected errors, rerun with: -v     
==15765== searching for pointers to 10,702 not-freed blocks.
==15765== checked 2,792,248 bytes.    
==15765==
==15765==
==15765== 795 bytes in 72 blocks are definitely lost in loss record 1 of 5 
==15765==    at 0x4C2136E: malloc (vg_replace_malloc.c:207) 
==15765==    by 0x503A34E: G__malloc (alloc.c:41)    
==15765==    by 0x505633B: G__location_path (location.c:77) 
==15765==    by 0x50562A6: G_location_path (location.c:57)  
==15765==    by 0x5051ECB: G__gisinit (gisinit.c:57) 
==15765==    by 0x401E14: main (main.c:87)    
==15765==
==15765==
==15765== 1,024 bytes in 1 blocks are definitely lost in loss record 2 of 5
==15765==    at 0x4C1F144: calloc (vg_replace_malloc.c:397) 
==15765==    by 0x503A3CC: G__calloc (alloc.c:74)    
==15765==    by 0x50609B6: G_recreate_command (parser.c:2468)
==15765==    by 0x505339D: G_command_history (history.c:257)
==15765==    by 0x402EF7: main (main.c:414)   
==15765==
==15765==
==15765== 6,380 bytes in 3 blocks are still reachable in loss record 3 of 5
==15765==    at 0x4C1F144: calloc (vg_replace_malloc.c:397) 
==15765==    by 0x503A3CC: G__calloc (alloc.c:74)    
==15765==    by 0x505BFF6: G_parser (parser.c:795)   
==15765==    by 0x401FEE: main (main.c:133)   
==15765==
==15765==
==15765== 16,016 bytes in 3 blocks are still reachable in loss record 4 of 5      
==15765==    at 0x4C2136E: malloc (vg_replace_malloc.c:207) 
==15765==    by 0x503A445: G__realloc (alloc.c:109)  
==15765==    by 0x5048375: set_env (env.c:172)
==15765==    by 0x5048136: read_env (env.c:114)
==15765==    by 0x504882F: G__getenv (env.c:337)
==15765==    by 0x5048771: G_getenv (env.c:289)
==15765==    by 0x5056297: G_location (location.c:37)
==15765==    by 0x5056300: G__location_path (location.c:75)
==15765==    by 0x50562A6: G_location_path (location.c:57)
==15765==    by 0x5051ECB: G__gisinit (gisinit.c:57)
==15765==    by 0x401E14: main (main.c:87)
==15765==
==15765==
==15765== 424,769 bytes in 10,623 blocks are still reachable in loss record 5 of 5
==15765==    at 0x4C2136E: malloc (vg_replace_malloc.c:207)
==15765==    by 0x503A34E: G__malloc (alloc.c:41)
==15765==    by 0x506FDE0: G_store (strings.c:83)
==15765==    by 0x506402D: G_set_program_name (progrm_nme.c:52)
==15765==    by 0x5051E92: G__gisinit (gisinit.c:51)
==15765==    by 0x401E14: main (main.c:87)
==15765==
==15765== LEAK SUMMARY:
==15765==    definitely lost: 1,819 bytes in 73 blocks.
==15765==      possibly lost: 0 bytes in 0 blocks.
==15765==    still reachable: 447,165 bytes in 10,629 blocks.
==15765==  suppressed: 0 bytes in 0 blocks.

I have no idea if that's acceptable or not.

Markus

comment:8 by hamish, 16 years ago

another report of it: http://lists.osgeo.org/pipermail/grass-windows/2008-November/001587.html


Benjamin Ducke wrote on the -dev list:

Michael,

this is a problem with dirty memory allocation that never got fixed.
On some systems, like Linux, the memory manager is a bit more "relaxed"
and lets this pass. On Windows, it's more strict and kills
the application. The crashes appear a bit random which is typical for
memory allocation problems. The more allocations involved (read: the bigger
you set max_dist), the more probable it becomes that a sensitive memory
region gets corrupted and the program bails out.

If anyone wants to have a go at it: use Valgrind on Linux. It will tell
you exactly where the bad allocations happen. I actually had a go at this
years ago and it was quite easy to fix, but lost my notes in the meantime.

From memory: the problem can be fixed by delaying the release of memory
allocated at the start of each run through the main loop.

I have attached a file "delete3.c" from r.cva for which I fixed the same problem.
I believe this file is identical to the version that r.los uses except for the
changes I made. Look for the string "DELAYED". You should find my comments and
additions. Replicate them for r.los and you _should_ be OK (provided there were
no substantial changes to r.los since I wrote my fixed).

In main.c, the following has to be added towards the top of the file:

  if (G_parser (argc, argv))
       exit(EXIT_FAILURE);

  G_sleep_on_error (0);


  /* initialize delayed point deletion */
  DELAYED_DELETE =  NULL;

And this toward the end:

  /* release that last tiny bit of memory ... */
  if ( DELAYED_DELETE != NULL ) {
      G_free ( DELAYED_DELETE );
  }

  return (0);
}

Unfortunately, I don't have the time to look into this myself at the moment.
Sorry for not being of more help. This is a long-standing, very annoying issue
that needs fixing urgently. It's embarassing to have such a basic tool fail in
this way.

Cheers,

Ben

comment:9 by neteler, 16 years ago

Consider to replace r.los with r.viewshed after fixing #390

comment:10 by hamish, 16 years ago

OK. I have replicated the memory allocation changes from r.cva.
It seems to run without bad allocs now. I cannot confirm that
it no longer crashes on Windows. Someone with a Windows GRASS
setup will need to do that.

The patch also contains a fix done by Mark Lake years ago that
never made it back into r.los. It fixes a problem with calculating
cell neighbourhoods in combination with raster masks (see. pts_elim.c).

Ben

applied to devbr6 in r36160.

in quick testing it looks like the MASK problem remains unfixed. (man page example)

Hamish

comment:11 by neteler, 16 years ago

Compiling the updated code with

MYCFLAGS="-g -Wall  -fno-common"
MYCXXFLAGS="-g -Wall"
MYLDFLAGS="-Wl,--no-undefined"
LDFLAGS="$MYLDFLAGS" CFLAGS="$MYCFLAGS" CXXFLAGS="$MYCXXFLAGS" ./configure ...

leads to this problem:

gcc -L/home/neteler/grass64/dist.x86_64-unknown-linux-gnu/lib -Wl,--no-undefined -Wl,--export-dynamic  
-L/usr/lib64 -Wl,-rpath-link,/home/neteler/grass64/dist.x86_64-unknown-linux-gnu/lib    -o /home/neteler/grass64/dist.x86_64-unknown-linux-gnu/bin/r.los OBJ.x86_64-unknown-linux-gnu/color_rnge.o 
OBJ.x86_64-unknown-linux-gnu/delete.o OBJ.x86_64-unknown-linux-gnu/main.o OBJ.x86_64-unknown-linux-gnu/make_list.o OBJ.x86_64-unknown-linux-gnu/make_point.o OBJ.x86_64-unknown-linux-gnu/mark_pts.o OBJ.x86_64-unknown-linux-gnu/pts_elim.o 
OBJ.x86_64-unknown-linux-gnu/segment.o  -lgrass_segment 
-lgrass_gis -lgrass_datetime -lz      -lgrass_gproj -lgrass_gis -lgrass_datetime -lz     -lproj  -L/usr/local/lib -lgdal  -lgrass_gis -lgrass_datetime -lz     -lm  -lz
OBJ.x86_64-unknown-linux-gnu/main.o: In function `main':
/home/neteler/grass64/raster/r.los/main.c:60: multiple definition of `DELAYED_DELETE'
OBJ.x86_64-unknown-linux-gnu/delete.o:/home/neteler/grass64/raster/r.los/delete.c:26: first defined here
OBJ.x86_64-unknown-linux-gnu/make_list.o: In function `make_list':
/home/neteler/grass64/raster/r.los/make_list.c:24: multiple definition of `DELAYED_DELETE'
OBJ.x86_64-unknown-linux-gnu/delete.o:/home/neteler/grass64/raster/r.los/delete.c:26: first defined here
OBJ.x86_64-unknown-linux-gnu/mark_pts.o: In function `mark_visible_points':
/home/neteler/grass64/raster/r.los/mark_pts.c:24: multiple definition of `DELAYED_DELETE'
OBJ.x86_64-unknown-linux-gnu/delete.o:/home/neteler/grass64/raster/r.los/delete.c:26: first defined here
OBJ.x86_64-unknown-linux-gnu/pts_elim.o: In function `hidden_point_elimination':
/home/neteler/grass64/raster/r.los/pts_elim.c:53: multiple definition of `DELAYED_DELETE'
OBJ.x86_64-unknown-linux-gnu/delete.o:/home/neteler/grass64/raster/r.los/delete.c:26: first defined here
OBJ.x86_64-unknown-linux-gnu/segment.o: In function `segment':
/home/neteler/grass64/raster/r.los/segment.c:24: multiple definition of `DELAYED_DELETE'
OBJ.x86_64-unknown-linux-gnu/delete.o:/home/neteler/grass64/raster/r.los/delete.c:26: first defined here
collect2: ld returned 1 exit status
make: *** [/home/neteler/grass64/dist.x86_64-unknown-linux-gnu/bin/r.los] Error 1

Attached patch cures it. Ok to submit?

Markus

by neteler, 16 years ago

Attachment: rlos.diff added

fix for compilation problem

comment:12 by neteler, 16 years ago

It crashes Linux (I have a 64bit box, using latest version of r.los):

GRASS 6.5.svn (patUTM32): > r.los pat_dtm_5m out=lavarone_viewshed_los coordinate=676769.91,5091720.66 obs_elev=42 max=30000
Using maximum distance from the viewing point (meters): 30000.000000
18%
Segmentation fault

GRASS 6.5.svn (patUTM32): > g.region -p
projection: 1 (UTM)
zone:       32
datum:      wgs84
ellipsoid:  wgs84
north:      5103410
south:      5084090
west:       653990
east:       684010
nsres:      10
ewres:      10
rows:       1932
cols:       3002
cells:      5799864

will post a gdb bt.

Markus

in reply to:  11 comment:13 by neteler, 16 years ago

Replying to neteler:

Attached patch cures it. Ok to submit?

Submitted in r36179, r36180, r36181.

now hunting the segfault...

Markus

comment:14 by neteler, 16 years ago

Here the backtrace of the segfault:

GRASS 6.5.svn (patUTM32):~ > gdb r.los                                                                   
GNU gdb 6.8-2mdv2009.0 (Mandriva Linux release 2009.0)                                                   
...
This GDB was configured as "x86_64-mandriva-linux-gnu"...                                                

(gdb) r pat_dtm_5m out=lavarone_viewshed_los coordinate=676769.91,5091720.66 obs_elev=42 max=30000 --o     
Starting program: /home/neteler/grass64/dist.x86_64-unknown-linux-gnu/bin/r.los pat_dtm_5m out=lavarone_viewshed_los coordinate=676769.91,5091720.66 obs_elev=42 max=30000 --o                                        
[Thread debugging using libthread_db enabled]                                                              
Using maximum distance from the viewing point (meters): 30000.000000                                       
  25%                                                                                                      
Program received signal SIGSEGV, Segmentation fault.                                                       
0x00007f8586b9c345 in memcpy () from /lib64/libc.so.6                                                      
(gdb) bt full                                                                                              
#0  0x00007f8586b9c345 in memcpy () from /lib64/libc.so.6                                                  
No symbol table info available.                                                                            
#1  0x00007f858856319f in segment_get (SEG=0x7fff9097cf80, buf=0x7fff9097b99c, row=-1, col=2277)           
    at get.c:49                                                                                            
        index = -2908                                                                                      
        n = 3                                                                                              
        i = 0                                                                                              
#2  0x0000000000403a2d in find_inclination (x=0, y=1169, viewpt_elev=1381, seg_in_p=0x7fff9097cf80,        
    row_viewpt=1168, col_viewpt=2277, docurv=0, ellps_a=6.9273684732832797e-310) at pts_elim.c:300         
        del_x = 0                                                                                          
        del_y = 1169                                                                                       
        dist = 11690                                                                                       
        picked_pt_elev = 1290.72095                                                                        
#3  0x0000000000403567 in hidden_point_elimination (head=0x461f0b0, viewpt_elev=1381,                      
    seg_in_p=0x7fff9097cf80, seg_out_p=0x7fff9097cf40, seg_patt_p=0x7fff9097cf00, quadrant=2,              
    sign_on_y=1, sign_on_x=-1, row_viewpt=1168, col_viewpt=2277, patt_flag=0, docurv=0,                    
    ellps_a=6.9273684732832797e-310) at pts_elim.c:99                                                      
        CHECKED_PT = (struct point *) 0x36f88b0                                                            
        BLOCKING_PT = (struct point *) 0x3706e30                                                           
        orientation_neighbor_1 = 1.5716524909692637                                                        
        orientation_neighbor_2 = 1.5707963267948966                                                        
        inclination_neighbor_1 = -0.0077292142003704354                                                    
        inclination_neighbor_2 = -0.0079553153874519812                                                    
        interpolated_inclination = 3.6327397940754172e-316                                                 
        correct_neighbor_inclination = -0.0073442512349566561                                              
        correct_neighbor_orientation = 1.5716532246142985                                                  
        correct_neighbor_x = -1                                                                            
        correct_neighbor_y = 1167                                                                          
        neighbor_1_y = 1168                                                                                
        neighbor_1_x = -1                                                                                  
        neighbor_2_x = 0                                                                                   
        neighbor_2_y = 1169                                                                                
        uu = 0                                                                                             
        vv = 1                                                                                             
        mask = 1                                                                                           
#4  0x0000000000403cb7 in segment (segment_no=5, xmax=1168, ymax=2277, slope_1=0, slope_2=0.5, flip=1,     
    sign_on_y=1, sign_on_x=-1, viewpt_elev=1381, seg_in_p=0x7fff9097cf80, seg_out_p=0x7fff9097cf40,        
    seg_patt_p=0x7fff9097cf00, row_viewpt=1168, col_viewpt=2277, patt_flag=0, docurv=0,                    
    ellps_a=6.9273684732832797e-310) at segment.c:81                                                       
        lower_limit_y = 0                                                                                  
        upper_limit_y = 0                                                                                  
        less = 0                                                                                           
        x = 0                                                                                              
        y = -1                                                                                             
        x_actual = 0                                                                                       
        y_actual = 1                                                                                       
        x_flip = 0                                                                                         
        y_flip = 1                                                                                         
        head = (struct point *) 0x461f0b0                                                                  
        PRESENT_PT = (struct point *) 0x5094270                                                            
        quadrant = 2                                                                                       
#5  0x0000000000402cdf in main (argc=7, argv=0x7fff9097d3d8) at main.c:328                                 
        row_viewpt = 1168                                                                                  
        col_viewpt = 2277                                                                                  
        nrows = 1932                                                                                       
        ncols = 3002                                                                                       
        a = 2277                                                                                           
        b = 1168                                                                                           
        row = 1932                                                                                         
        patt_flag = 0                                                                                      
        segment_no = 5                                                                                     
        flip = 1                                                                                           
        xmax = 1168                                                                                        
        ymax = 2277                                                                                        
        sign_on_y = 1                                                                                      
        sign_on_x = -1                                                                                     
        submatrix_rows = 484                                                                               
        submatrix_cols = 751                                                                               
        lenth_data_item = 4                                                                                
        patt = 0                                                                                           
        in_fd = 8                                                                                          
        out_fd = 9                                                                                         
        patt_fd = 0                                                                                        
        old = 6                                                                                            
        new = 7                                                                                            
        slope_1 = 0                                                                                        
        slope_2 = 0.5                                                                                      
        max_vert_angle = 0                                                                                 
        color_factor = 6.9532634621160482e-310                                                             
        old_mapset = 0x2079260 "PERMANENT"                                                                 
        patt_mapset = 0x0                                                                                  
        value = (FCELL *) 0x7fff9097cfc8                                                                   
        search_mapset = 0x404020 ""                                                                        
        current_mapset = 0x7f858855ca40 "neteler"                                                          
        in_name = 0x2078f90 "/4/grassdata/patUTM32/neteler/.tmp/localhost/16164.2"                         
        out_name = 0x2078fd0 "/4/grassdata/patUTM32/neteler/.tmp/localhost/16164.3"                        
        patt_name = 0x0                                                                                    
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      inf_min = 1989, inf_max = 1}}, labels = 0x7f8588952d20, marks = 0x7f858897e358,                      
  nalloc = -1869098208, last_marked_rule = 32767}                                                          
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  cols3 = 0, depths = -2005476696, proj = 32645, zone = 23, ew_res = 6.927368471377372e-310,               
  ew_res3 = 1.1363509854348671e-322, ns_res = 6.92736847137421e-310, ns_res3 = 7.4109846876186982e-323,    
  tb_res = 1.9268560187808615e-322, north = 1.5065906837361573e-314, south = 6.927368375482738e-310,       
  east = 7.4109846876186982e-323, west = 6.9273684713750005e-310, top = 8.3991159793011913e-323,           
  bottom = 1.9268560187808615e-322}                                                                        
        cell = (CELL *) 0x7fff9097d418                                                                     
        fcell = (FCELL *) 0x2079330                                                                        
        data = 4.57453884e-41                                                                              
        viewpt_elev = 1381.43994                                                                           
        seg_in = {open = 1, nrows = 1932, ncols = 3002, len = 4, srows = 484, scols = 751,                 
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        seg_out = {open = 1, nrows = 1932, ncols = 3002, len = 4, srows = 484, scols = 751,                
  size = 1453936, spr = 4, spill = 749, fd = 9, scb = 0x20ada80, nseg = 4, cur = 1, offset = 20}           
        seg_patt = {open = -2035101336, nrows = 32645, ncols = -2005511248, len = 32645, srows = 0,        
  scols = 0, size = -2005476696, spr = 32645, spill = 4198278, fd = 0, scb = 0x7f85889478e0, nseg = 9,     
  cur = 0, offset = 39}                                                                                    
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  0x7f85887656dc}                                                                                          
        SEARCH_PT = (struct point *) 0x7f8587a881e0                                                        
        module = (struct GModule *) 0x7f858855cf20                                                         
        opt1 = (struct Option *) 0x7f858855ce80                                                            
        opt2 = (struct Option *) 0x2078450                                                                 
        opt3 = (struct Option *) 0x2078380                                                                 
        opt5 = (struct Option *) 0x2078520                                                                 
        opt6 = (struct Option *) 0x20785f0                                                                 
        opt7 = (struct Option *) 0x20782b0                                                                 
        curvature = (struct Flag *) 0x7f858855ce40                                                         
        history = {                                                                                        
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    '\0' <repeats 12 times>, "��\227\220�\177\000\000\002\vw\210\205\177\000\000\001\000\000\000�\177\000\000(\005\230\210\205\177\000\000\200�\227\220�\177\000\000\000\000\000\000\000\000\000\0007%�\206\205\177\000\000\a\nw\210\205\177\000\000(\005\230\210",                                                              
    "\205\177\000\000\000\000\000\000\000\000\000\000X\000\000\000\000\000\000\000(\030�\206\205\177\000\000\000\000@�/!��\230\000\000\000\000\000\000\000�\r\020\207\205\177", '\0' <repeats 11 times>, "\020\225\210\205\177\000\000\000\000`\205/!��\000\000VC",                                                              
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    "�\020\v�\000\000\000\000\000\000\000\000�L\236\207\205\177\000\000\020\000\000\000\000\000\000\000�)\225\210\205\177\000\000\000\000�\207/!��\000\000VC�\020\v�\000\000\000\000\000\000\000\000�L\236\207\205\177\000\000\016\000\000\000\000\000\000\000�)\225\210",                                                       
    "\205\177\000\000\000\000\000\210/!��\000\000VC�\020\v�\000\000\000\000\000\000\000\000�L\236\207\205\177\000\000\r\000\000\000\000\000\000\000�)\225\210\205\177\000\000\000\000`\210/!��\000\000VC�\020\v�\000\000\000\000\000\000\000\000\000�\224\210",                                                                  
    "\205\177\000\000\002\vw\210\205\177\000\000\001\000\000\000\205\177\000\000��\224\210\205\177\000\000��\227\220�\177\000\000\000\000\000\000\000\000\000\000�G\033\207\205\177\000\000\a\nw\210\205\177\000\000\001\000\000\000\205\177\000\000\000�\224\210\205\177\000\000��\227\220",                                    
    "�\177\000\000\000\000\000\000\000\000\000\000�G\033\207\205\177\000\000\a\nw\210\205\177\000\000\001\000\000\000\205\177\000\000x�\224\210\205\177\000\000\000�\227\220�\177\000\000\000\000\000\000\000\000\000\000�G\033\207\205\177\000\000\a\nw\210\205\177\000\000\001\000\000",                                       
    "\205\177\000\000��\224\210\205\177\000\0000�\227\220�\177\000\000\000\000\000\000\000\000\000\000�G\033\207\205\177\000\000\a\nw\210\205\177\000\000\001\000\000\000\205\177\000\000\000�\224\210\205\177\000\000`�\227\220�\177\000\000\000\000\000\000\000\000\000\000\230G\033\207",                                     
    "\205\177\000\000\a\nw\210\205\177\000\000\001\000\000\000\205\177\000\000\220�\224\210\205\177\000\000\220�\227\220�\177\000\000\000\000\000\000\000\000\000\000\212G\033\207\205\177\000\000\a\nw\210\205\177\000\000\001\000\000\000\205\177\000\000��\224\210\205\177\000\000��\227\220",                                
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    "\205\177\000\000\210�\224\210\205\177\000\000 �\227\220�\177\000\000\000\000\000\000\000\000\000\000\\G\033\207\205\177\000\000\a\nw\210\205\177\000\000\001\000\000\000\205\177\000\000��\224\210\205\177\000\000P�\227\220�\177\000\000\000\000\000\000\000\000\000\000MG\033\207",                                       
    "\205\177\000\000\a\nw\210\205\177\000\000\001\000\000\000\205\177\000\000\000�\224\210\205\177\000\000\200�\227\220�\177\000\000\000\000\000\000\000\000\000\000=G\033\207\205\177\000\000\a\nw\210\205\177\000\000\001\000\000\000\0000\205��\t\225\210\205\177\000\000��\227\220",                                        
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    "\205\177\000\000\210�\224\210\205\177\000\000\000�\224\210\205\177\000\000��\224\210\205\177\000\000\220�\224\210\205\177\000\000\000�\224\210\205\177\000\000\030�\227\210\205\177\000\000��\224\210\205\177\000\000�\031\225\210\205\177\000\000x�\224\210\205\177\000\000\000�\224\210",                                 
    "\205\177\000\000\000\020\225\210\205\177\000\000��\224\210\205\177\000\000�\024\225\210\205\177\000\000\000\000\000\000\000\000\000\000\001\000\000\000\000\000\000\000\000%\225\210\205\177\000\000\000\000@\217/!��\000\000VC�\020\v�0�\227\220�\177\000\000��\227\220",                                                  
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    "\000\000\000\0000�\227\220�\177\000\000��\227\220�\177\000\000\020\000\000\000\000\000\000\000P\226\016\210\205\177\000\000\000\000\000\000\000\000\000\000\030�\227\210\205\177\000\000�\002w\210\205\177\000\000\000\000\000\000\000\000\000\000\004\000\000\000\000\000\000\000\000\000\000",                            
    "\000\000\000\000�!w\210\205\177\000\0000�\227\220�\177\000\000p\002w\210\205\177\000\000o�\227\220�\177\000\000\000\000\000\000\000\000\000\000\220\037\225\210\205\177\000\000\002\vw\210\205\177\000\000\000�\227\210\205\177\000\000 �\227\210\205\177\000\000\030�\227\210",                                            
    "\205\177\000\000\000%\225\210\205\177\000\000�)\225\210\205\177\000\000\000\020\225\210\205\177\000\000�\024\225\210\205\177\000\000\000\000\000\000\000\000\000\000\030�\227\210\205\177\000\000\000\000\000\223/!��\000\000VC�\020\v�0�\227\220�\177\000\000��\227\220",                                                  
    "�\177\000\0000\000\000\000\000\000\000\000(0/\210\205\177\000\000\000\000\000\000\000\000\000\000 �\227\210\205\177\000\000�\002w\210\205\177", '\0' <repeats 14 times>, "\036", '\0' <repeats 11 times>, "�!w\210\205\177\000\0000�\227\220",                                                                              
    "�\177\000\000p\002w\210\205\177\000\000o�\227\220�\177\000\000`�\227\220�\177\000\000X�\227\220�\177\000\0008\v\230\210\205\177\000\000a�\000��S\200\030\000\000\000\000\000\000\000\000��\227\220�\177\000\000\002\vw\210\205\177\000\000�\024\225\210",                                                                   
    "\205\177\000\000\000\000\000\000\000\000\000\000(0/\210\205\177\000\000\000\000\000\000\000\000\000\000 �\227\210\205\177\000\000\000\000�\224/!��\000\000VC�\020\v�\000\000\000\000\000\000\000\000�\201U\210\205\177\000\000\004\000\000\000\000\000\000\000\000�\227\210",                                               
    "\205\177\000\000�\002w\210\205\177", '\0' <repeats 26 times>, "�!w\210\205\177\000\0000�\227\220�\177\000\000p\002w\210\205\177\000\000o�\227\220�\177\000\000`�\227\220�\177\000\000X�\227\220",                
    "�\177\000\0008\v\230\210\205\177\000\0000�\227\220�\177\000\000\000\000\000\000\000\000\000\000o�\227\220�\177\000\000\000\000\000\000\000\000\000\000��\227\220�\177\000\000\002\vw\210\205\177\000\000�\024\225\210\205\177", '\0' <repeats 11 times>, "�\227\210",                                                       
    "\205\177\000\000\000\000`\226/!��\000\000VC�\020\v�\000\000\000\000\000\000\000\000�\201U\210\205\177\000\000\003\000\000\000\000\000\000\000\000�\227\210\205\177\000\000\000\000�\226/!��\000\000VC�\020\v�\b\0---Type <return> to continue, or q <return> to quit---
00\000\000\000\000\000\000R�td",
    "\004\000\000\0000�\227\220�\177\000\000��\227\220�\177\000\000\000\000\000\000\000\000\000\000�Fv\210\205\177\000\000\003\000\000\000\000\000\000\000\030�\227\210\205\177\000\000�\002w\210\205\177", '\0' <repeats 14 times>, "\002\000\000\000\000\000\000",
    '\0' <repeats 12 times>, "�\036\225\210\205\177\000\000\002\vw\210\205\177\000\000\001\000\000\000�\177\000\000�\031\225\210\205\177\000\000@�\227\220�\177\000\000\000\000\000\000\000\000\000\000\207�/\210\205\177\000\000\a\nw\210\205\177\000\000\030�\227\210",
    "\205\177\000\000 �\227\210\205\177\000\000\000\020\225\210\205\177\000\000�\031\225\210\205\177\000\000�\024\225\210\205\177\000\000\000\000\000\000\000\000\000\000\030�\227\210\205\177\000\000\000\000�\230/!��\000\000VC�\020\v�B�\203�٤X\002\b\004\020@",
    "\a\020\004\002\220@\"\000 \032\020\002\031\004F&\000\001����\227\220�\177\000\000�\024\225\210\205\177\000\000\200\000@\023\020\000k\000!\204*\n\002\000 \0000�\227\220�\177\000\000��\227\220�\177", '\0' <repeats 11 times>, "F`",
    '\0' <repeats 13 times>, "�\227\210\205\177\000\000�\002w\210\205\177", '\0' <repeats 34 times>, "\210\031\225\210\205\177\000\000\002\vw\210\205\177\000\000\000�\227\210",
    "\205\177\000\000 �\227\210\205\177\000\000\030�\227\210\205\177\000\000�\024\225\210\205\177", '\0' <repeats 18 times>, "o�\227\220�\177\000\000�\017@\000\000\000\000\000\000\000@�/!��\000\000\000\000\000\000\000\000\000F`",
    '\0' <repeats 13 times>, "�\227\210\205\177\000\000\000\000�\232/!��\000\000VC�\020\v�\000\000\000\000\000\000\000\000�E`", '\0' <repeats 14 times>, "�\227\210\205\177\000\000\000\000@\233/!��\000\000VC",
    "�\020\v�\000\000\000\000\000\000\000\000�E`", '\0' <repeats 14 times>, "�\227\210\205\177\000\000\000\000�\233/!��\000\000VC�\020\v�\000\000\000\000\000\000\000\000�E`", '\0' <repeats 13 times>, "\001\000\000"}}
        title = "�\024\225\210\205\177\000\000��\224\210\205\177", '\0' <repeats 18 times>, "�\022�\205\205\177\000\000\005\000\000\000\000\000\000\000��\224\210\205\177\000\000\000\000 w/!��\000\000VC�\020\v�", '\0' <repeats 16 times>, "5.w\210\205\177\000\000\000\000\000\000\000\000\000\000(\005\230\210\205\177\000\000A\230\221\206\205\177\000\0000�\227\220�\177\000"
        aa = 6.9273684732832797e-310
        e2 = 6.9273684722714332e-310
(gdb)

in reply to:  14 comment:15 by glynn, 16 years ago

Replying to neteler:

#1 0x00007f858856319f in segment_get (SEG=0x7fff9097cf80, buf=0x7fff9097b99c, row=-1, col=2277)

row=-1

#2 0x0000000000403a2d in find_inclination (x=0, y=1169, viewpt_elev=1381, seg_in_p=0x7fff9097cf80, row_viewpt=1168, col_viewpt=2277, docurv=0, ellps_a=6.9273684732832797e-310) at pts_elim.c:300

y=1169, row_viewpt=1168

=> y > row_viewpt

#3 0x0000000000403567 in hidden_point_elimination (...) at pts_elim.c:99

This is where I get lost.

comment:16 by aborruso, 16 years ago

I have made a test with the new installer for grass-6.4.0RC3, made by Colin Nielsen, and now r.los seems ok.

I must do other tests.

comment:17 by gsancho, 16 years ago

I have also made some tests with r.los operation and it keep failing (as it does in other versions)

comment:18 by hamish, 15 years ago

does it still break with 6.4.0rc4?

Hamish

in reply to:  18 comment:19 by aborruso, 15 years ago

Hi Replying to hamish:

does it still break with 6.4.0rc4?

Hamish

I have made a test with 6.4.0SVN-r36903-1, and it does not crash.

Andrea

in reply to:  17 ; comment:20 by hamish, 15 years ago

Replying to gsancho:

I have also made some tests with r.los operation and it keep failing (as it does in other versions)

what version do you test with? same spearfish command line as in the original bug report?

I've just tested r.los in the latest stand-alone WinGRASS installer and it the only problem I noticed was that the G_percent() text only gets displayed as 100% after the process is complete, after any module output (run from msys command line).

I tested these:

#spearfish
r.los in=elevation.dem output=tr_vis \
   coordinate=599490,4920855 max_dist=10000

r.los input=elevation.dem output=los \
   coordinate=599505,4921010 max_dis=2525


#NC_spm_08
r.los in=elevation out=ele.los coord=637500,221750 \
   obs_elev=42 max=10000

all without crashing.

Hamish

comment:21 by hamish, 15 years ago

gsancho: any more details you can provide about how to trigger the crash?

in reply to:  20 ; comment:22 by hellik, 15 years ago

Replying to hamish:

all without crashing.

grass64.svn rev39432 self compiled in the osgeo4w-stack, WinVista32 nc-dataset

r.los input=elevation@PERMANENT output=rlostest coordinate=637101,223211        
Using maximum distance from the viewing point (meters): 10000.000000

all without crashing

closing the ticket?

best regards helli

in reply to:  22 comment:23 by aborruso, 15 years ago

Hi helli, for me yes. I have had this problem in the past, but it's all ok with WinGRASS-6.4.0SVN-r39271-1. I have made a test with this command:

r.los --overwrite input=DEM@PERMANENT output=vis coordinate=304000,4211134 max_dist=50000

Thank you,

a

in reply to:  17 comment:24 by hamish, 15 years ago

Replying to gsancho:

I have also made some tests with r.los operation and it keep failing (as it does in other versions)

still seeing this?

Hamish

comment:25 by pcav, 15 years ago

Confirmed on GRASS 6.4.0~rc5+40109-1 from Debian unstable

comment:26 by pcav, 15 years ago

Summary: r.los fails in WinGRASS with high values for max_dis parameterr.los fails with high values for max_dis parameter

in reply to:  25 comment:27 by hamish, 15 years ago

Replying to pcav:

Confirmed on GRASS 6.4.0~rc5+40109-1 from Debian unstable

more details please:

do you see it using an example from one of the sample datasets? (spearfish or NC)

what was the command line you used, region settings, etc?

is this on 32 or 64 bit?

thanks, Hamish

comment:28 by hamish, 15 years ago

(see details on grass-user ML, Wednesday, December 30, 2009)

can you provide a gdb backtrace for r.los run from the grass command line?

thanks, Hamish

comment:29 by pcav, 15 years ago

I tested this on my own data, on amd64. On NC data I cannot reproduce it, but this may be due to a lower resolution.

Command line: r.los input=dtm@PERMANENT coordinate=1676844,4830417 obs_elev=50 max_dist=5000 output=los4 Using maximum distance from the viewing point (meters): 5000.000000 Module crashed or killed

This both from QGIS plugin and from the console.

g.region -p

projection: 99 (Transverse Mercator) zone: 0 datum: rome40 ellipsoid: international north: 4834913.78536118 south: 4803364.45415656 west: 1650370.47056664 east: 1689398.62729587 nsres: 24.99947005 ewres: 25.00202225 rows: 1262 cols: 1561 cells: 1969982

comment:30 by pcav, 15 years ago

Unable to reproduce it with NC sample data - it takes a *lot* of time and CPU there, but seems to work anyway. I can make my region available for futher testing if necessary.

in reply to:  30 comment:31 by hamish, 15 years ago

Replying to pcav:

I can make my region available for futher testing if necessary.

yes please

Hamish

comment:32 by pcav, 15 years ago

Here it is (available for a while):

http://int.faunalia.it/~paolo/Toscana_rlos.tar.gz

Tested again with the command

r.los input=dtm@PERMANENT coordinate=1676734,4831167 obs_elev=100 max_dist=10000 output=rlos

and it fails

in reply to:  32 comment:33 by hamish, 15 years ago

Replying to pcav:

http://int.faunalia.it/~paolo/Toscana_rlos.tar.gz

Tested again with the command

r.los input=dtm@PERMANENT coordinate=1676734,4831167 obs_elev=100 max_dist=10000 output=rlos

and it fails

works for me on debian-etch-pentium4, (& it looks nice too!)

http://bambi.otago.ac.nz/hamish/grass/bugs/rlos_onearth.jpg

but I do see the segfault on debian-lenny-amd64 & GRASS 6.5svn.

gdb session:

G65> gdb `which r.los`
...
(gdb) run input=dtm@PERMANENT coordinate=1676734,4831167 obs_elev=100 max_dist=10000 output=rlos_test
...
[Thread debugging using libthread_db enabled]
warning: Lowest section in /usr/lib/libicudata.so.38 is .hash at 0000000000000120
Using maximum distance from the viewing point (meters): 10000.000000
[New Thread 0x7fde555ce710 (LWP 31319)]

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7fde555ce710 (LWP 31319)]
0x00007fde53ae9ee5 in memcpy () from /lib/libc.so.6

(gdb) bt
#0  0x00007fde53ae9ee5 in memcpy () from /lib/libc.so.6
#1  0x00007fde552eb288 in segment_get (SEG=0x7fff7c5cf320, buf=0x7fff7c5cdd2c, row=-1, 
    col=1054) at get.c:49
#2  0x0000000000403b3e in find_inclination (x=0, y=150, viewpt_elev=249, 
    seg_in_p=0x7fff7c5cf320, row_viewpt=149, col_viewpt=1054, docurv=0, 
    ellps_a=6.9532466931849492e-310) at pts_elim.c:300
#3  0x000000000040361f in hidden_point_elimination (head=0x16a2340, viewpt_elev=249, 
    seg_in_p=0x7fff7c5cf320, seg_out_p=0x7fff7c5cf2e0, seg_patt_p=0x7fff7c5cf2a0, 
    quadrant=1, sign_on_y=1, sign_on_x=1, row_viewpt=149, col_viewpt=1054, patt_flag=0, 
    docurv=0, ellps_a=6.9532466931849492e-310) at pts_elim.c:94
#4  0x0000000000403de7 in segment (segment_no=4, xmax=149, ymax=506, slope_1=0, 
    slope_2=0.5, flip=1, sign_on_y=1, sign_on_x=1, viewpt_elev=249, 
    seg_in_p=0x7fff7c5cf320, seg_out_p=0x7fff7c5cf2e0, seg_patt_p=0x7fff7c5cf2a0, 
    row_viewpt=149, col_viewpt=1054, patt_flag=0, docurv=0, 
    ellps_a=6.9532466931849492e-310) at segment.c:81
#5  0x0000000000402dc0 in main (argc=6, argv=0x7fff7c5cf778) at main.c:328

(gdb) frame 1
#1  0x00007fde552eb288 in segment_get (SEG=0x7fff7c5cf320, buf=0x7fff7c5cdd2c, row=-1, 
    col=1054) at get.c:49
49          memcpy(buf, &SEG->scb[i].buf[index], SEG->len);

(gdb) list
43          int index, n, i;
44      
45          segment_address(SEG, row, col, &n, &index);
46          if ((i = segment_pagein(SEG, n)) < 0)
47              return -1;
48      
49          memcpy(buf, &SEG->scb[i].buf[index], SEG->len);
50      
51          return 1;
52      }

(gdb) bt full
#0  0x00007fde53ae9ee5 in memcpy () from /lib/libc.so.6
No symbol table info available.
#1  0x00007fde552eb288 in segment_get (SEG=0x7fff7c5cf320, buf=0x7fff7c5cdd2c, row=-1, 
    col=1054) at get.c:49
        index = -476
        n = 2
        i = 0

so buf[index] on line 49 of lib/segment/get.c is trying to look for buf[-476] and generally speaking negative array positions are not allowed.

That row=-1 looks a bit suspicious...

I can follow that back as far as r.los/pts_elim.c L94 where row_viewpt=149 but neighbor_1_y=150, so row_viewpt - neighbor_1_y = -1.

"g.region res=25 -a" does not fix it.

Hamish

ps- more of the backtrace follows

#2  0x0000000000403b3e in find_inclination (x=0, y=151, viewpt_elev=250, 
    seg_in_p=0x7fff36385b80, row_viewpt=150, col_viewpt=1055, docurv=0, 
    ellps_a=6.9531885513800646e-310) at pts_elim.c:300
        del_x = 0
        del_y = 151
        dist = 3775
        picked_pt_elev = 1.40129846e-45
#3  0x000000000040361f in hidden_point_elimination (head=0xf185c0, viewpt_elev=250, 
    seg_in_p=0x7fff36385b80, seg_out_p=0x7fff36385b40, seg_patt_p=0x7fff36385b00, 
    quadrant=1, sign_on_y=1, sign_on_x=1, row_viewpt=150, col_viewpt=1055, patt_flag=0, 
    docurv=0, ellps_a=6.9531885513800646e-310) at pts_elim.c:94
        CHECKED_PT = (struct point *) 0xf34df0
        BLOCKING_PT = (struct point *) 0xf5f780
        orientation_neighbor_1 = 1.5707963267948966
        orientation_neighbor_2 = 1.5641297588910283
        inclination_neighbor_1 = -0.0080127842385963374
        inclination_neighbor_2 = -0.0080487974672544659
        interpolated_inclination = 7.8202765736839203e-317
        correct_neighbor_inclination = -0.0080487974672544659
        correct_neighbor_orientation = 1.5640850181635739
        correct_neighbor_x = 1
        correct_neighbor_y = 149
        neighbor_1_y = 151
        neighbor_1_x = 0
        neighbor_2_x = 1
        neighbor_2_y = 150
        uu = 1
        vv = 0
        mask = 1072693248
#4  0x0000000000403de7 in segment (segment_no=4, xmax=150, ymax=506, slope_1=0, 
    slope_2=0.5, flip=1, sign_on_y=1, sign_on_x=1, viewpt_elev=250, 
    seg_in_p=0x7fff36385b80, seg_out_p=0x7fff36385b40, seg_patt_p=0x7fff36385b00, 
    row_viewpt=150, col_viewpt=1055, patt_flag=0, docurv=0, 
    ellps_a=6.9531885513800646e-310) at segment.c:81
        lower_limit_y = 0
        upper_limit_y = 0
        less = 0
        x = 0
        y = -1
        x_actual = 0
        y_actual = 1
        x_flip = 0
        y_flip = 1
        head = (struct point *) 0xf185c0
        PRESENT_PT = (struct point *) 0xe8aa50
        quadrant = 1
#5  0x0000000000402dc0 in main (argc=6, argv=0x7fff36385fd8) at main.c:328
        row_viewpt = 150
        col_viewpt = 1055
        nrows = 1263
        ncols = 1562
        a = 506
        b = 150
        row = 1263
        patt_flag = 0
        segment_no = 4
        flip = 1
        xmax = 150
        ymax = 506
        sign_on_y = 1
        sign_on_x = 1
        submatrix_rows = 316
        submatrix_cols = 391
        lenth_data_item = 4
        patt = 0
        in_fd = 7
        out_fd = 8
        patt_fd = 0
        old = 5
        new = 6
        slope_1 = 0
        slope_2 = 0.5
        max_vert_angle = 0
        color_factor = 6.9531885516330262e-310
        old_mapset = 0xdb3510 "PERMANENT"
        patt_mapset = 0x0
        value = (FCELL *) 0x7fff36385bc8
        search_mapset = 0x404148 ""
        current_mapset = 0x7f937cbb1920 "paolo"
...[cut]

comment:34 by hamish, 15 years ago

I would note that your starting point is 150 rows (+/- 1) from the northern edge of the map, which is the y it blows up on.

north:      4834913.78536118
nsres:      24.99947005

coordinate=1676734,4831167

( 4834913.78536118 - 4831167 ) / 24.99947005
ans =     149.874591488794

setting the starting coord at the center of the map (dist to edge > max_dist) allows it to run to completion.

so it is some just tipping over the edge effect, ie integer truncation or rounding error ... ???

Hamish

in reply to:  32 comment:35 by hellik, 15 years ago

Replying to pcav:

Here it is (available for a while):

http://int.faunalia.it/~paolo/Toscana_rlos.tar.gz

Tested again with the command

r.los input=dtm@PERMANENT coordinate=1676734,4831167 obs_elev=100 max_dist=10000 output=rlos

and it fails

tested it with an actual self compiled grass64 and grass65 on WinVista32, r.los works in both versions.

Helmut

comment:36 by pcav, 15 years ago

Resolution: fixed
Status: newclosed

I can confirm, it works quickly and smoothing on debian with official package 6.4.0~rc5+41380-1.

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