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| author | Jasper van de Gronde <jasper.vandegronde@gmail.com> | 2009-04-05 19:46:56 +0000 |
|---|---|---|
| committer | jaspervdg <jaspervdg@users.sourceforge.net> | 2009-04-05 19:46:56 +0000 |
| commit | 602b341cf71d26e58163fdce6f9a1aa607d432aa (patch) | |
| tree | 43682fcf4617b92a2e8047fbc2f74357c0de98e4 /src/display | |
| parent | Fixes some wrong uses of CLAMP_D_TO_U8 in filtering code (mostly based on my ... (diff) | |
| download | inkscape-602b341cf71d26e58163fdce6f9a1aa607d432aa.tar.gz inkscape-602b341cf71d26e58163fdce6f9a1aa607d432aa.zip | |
Reverts "fix" of offset in the displacement map code (and adds a comment to prevent another misunderstanding).
(bzr r7628)
Diffstat (limited to 'src/display')
| -rw-r--r-- | src/display/nr-filter-displacement-map.cpp | 22 |
1 files changed, 9 insertions, 13 deletions
diff --git a/src/display/nr-filter-displacement-map.cpp b/src/display/nr-filter-displacement-map.cpp index 3c59d70e7..4cd0f5160 100644 --- a/src/display/nr-filter-displacement-map.cpp +++ b/src/display/nr-filter-displacement-map.cpp @@ -9,12 +9,6 @@ * Released under GNU GPL, read the file 'COPYING' for more information */ -#include <cmath> -#if defined (SOLARIS) && (SOLARIS == 8) -#include "round.h" -using Inkscape::round; -#endif - #include "display/nr-filter-displacement-map.h" #include "display/nr-filter-types.h" #include "display/nr-filter-units.h" @@ -56,16 +50,18 @@ static inline pixel_t pixelValue(NRPixBlock const* pb, int x, int y) { template<bool PREMULTIPLIED> static pixel_t interpolatePixels(NRPixBlock const* pb, double x, double y) { + // NOTE: The values of x and y are shifted by -0.5 (the "true" values would be x+0.5 and y+0.5). + // This is done because otherwise the pixel values first have to be shifted by +0.5 and then by -0.5 again... unsigned int const sfl = 8u; unsigned int const sf = 1u<<sfl; unsigned int const sf2h = 1u<<(2u*sfl-1); - int xi = (int)round(x), yi = (int)round(y); - unsigned int xf = static_cast<unsigned int>(round(sf * (x - (xi - 0.5)))), - yf = static_cast<unsigned int>(round(sf * (y - (yi - 0.5)))); - pixel_t p00 = pixelValue(pb, xi-1, yi-1); - pixel_t p01 = pixelValue(pb, xi-0, yi-1); - pixel_t p10 = pixelValue(pb, xi-1, yi-0); - pixel_t p11 = pixelValue(pb, xi-0, yi-0); + int xi = (int)floor(x), yi = (int)floor(y); + unsigned int xf = static_cast<unsigned int>(round(sf * (x - xi))), + yf = static_cast<unsigned int>(round(sf * (y - yi))); + pixel_t p00 = pixelValue(pb, xi+0, yi+0); + pixel_t p01 = pixelValue(pb, xi+1, yi+0); + pixel_t p10 = pixelValue(pb, xi+0, yi+1); + pixel_t p11 = pixelValue(pb, xi+1, yi+1); /* It's a good idea to interpolate premultiplied colors: * |