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| author | Kristian Evers <kristianevers@gmail.com> | 2018-05-23 13:14:48 +0200 |
|---|---|---|
| committer | Kristian Evers <kristianevers@gmail.com> | 2018-05-23 13:41:08 +0200 |
| commit | f5c8188faa44ba8dbae533c295d6ae013422f3b9 (patch) | |
| tree | e98d10ce0ea6dafb2caf101a1eadc8fd67c8952b /src/pj_apply_vgridshift.c | |
| parent | 58cbb9fe4f89b9febd780f7bdcfa4c2bb74a723e (diff) | |
| parent | 37ebb8f9f0cc5083d22f84433fb2de0fdde8be00 (diff) | |
| download | PROJ-f5c8188faa44ba8dbae533c295d6ae013422f3b9.tar.gz PROJ-f5c8188faa44ba8dbae533c295d6ae013422f3b9.zip | |
Merge branch 'master' into return-nans-quickly
Diffstat (limited to 'src/pj_apply_vgridshift.c')
| -rw-r--r-- | src/pj_apply_vgridshift.c | 68 |
1 files changed, 52 insertions, 16 deletions
diff --git a/src/pj_apply_vgridshift.c b/src/pj_apply_vgridshift.c index b5b35640..c1344951 100644 --- a/src/pj_apply_vgridshift.c +++ b/src/pj_apply_vgridshift.c @@ -28,11 +28,22 @@ #define PJ_LIB__ +#include <stdio.h> #include <string.h> + #include "proj_math.h" #include "proj_internal.h" #include "projects.h" +static int is_nodata(float value) +{ + /* nodata? */ + /* GTX official nodata value if -88.88880f, but some grids also */ + /* use other big values for nodata (e.g naptrans2008.gtx has */ + /* nodata values like -2147479936), so test them too */ + return value > 1000 || value < -1000 || value == -88.88880f; +} + static double read_vgrid_value( PJ *defn, LP input, int *gridlist_count_p, PJ_GRIDINFO **tables, struct CTABLE *ct) { int itable = 0; double value = HUGE_VAL; @@ -110,23 +121,49 @@ static double read_vgrid_value( PJ *defn, LP input, int *gridlist_count_p, PJ_GR grid_iy2 = ct->lim.phi - 1; cvs = (float *) ct->cvs; - value = cvs[grid_ix + grid_iy * ct->lim.lam] - * (1.0-grid_x) * (1.0-grid_y) - + cvs[grid_ix2 + grid_iy * ct->lim.lam] - * (grid_x) * (1.0-grid_y) - + cvs[grid_ix + grid_iy2 * ct->lim.lam] - * (1.0-grid_x) * (grid_y) - + cvs[grid_ix2 + grid_iy2 * ct->lim.lam] - * (grid_x) * (grid_y); + { + float value_a = cvs[grid_ix + grid_iy * ct->lim.lam]; + float value_b = cvs[grid_ix2 + grid_iy * ct->lim.lam]; + float value_c = cvs[grid_ix + grid_iy2 * ct->lim.lam]; + float value_d = cvs[grid_ix2 + grid_iy2 * ct->lim.lam]; + double total_weight = 0.0; + int n_weights = 0; + value = 0.0f; + if( !is_nodata(value_a) ) + { + double weight = (1.0-grid_x) * (1.0-grid_y); + value += value_a * weight; + total_weight += weight; + n_weights ++; + } + if( !is_nodata(value_b) ) + { + double weight = (grid_x) * (1.0-grid_y); + value += value_b * weight; + total_weight += weight; + n_weights ++; + } + if( !is_nodata(value_c) ) + { + double weight = (1.0-grid_x) * (grid_y); + value += value_c * weight; + total_weight += weight; + n_weights ++; + } + if( !is_nodata(value_d) ) + { + double weight = (grid_x) * (grid_y); + value += value_d * weight; + total_weight += weight; + n_weights ++; + } + if( n_weights == 0 ) + value = HUGE_VAL; + else if( n_weights != 4 ) + value /= total_weight; + } } - /* nodata? */ - /* GTX official nodata value if -88.88880f, but some grids also */ - /* use other big values for nodata (e.g naptrans2008.gtx has */ - /* nodata values like -2147479936), so test them too */ - if( value > 1000 || value < -1000 || value == -88.88880f ) - value = HUGE_VAL; - return value; } @@ -292,4 +329,3 @@ double proj_vgrid_value(PJ *P, LP lp){ return value; } - |