X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=src%2Fdisplay%2Fpixblock-scaler.cpp;h=511104c43a04c98e05306febca8cca6890245e7e;hb=0d6b11f64a38b998cdb42c9632358575daa1ac0a;hp=c5acaace0b3e5f4f033accc3ac7457715e031dcd;hpb=0462423d3cc0333b913735352429f053b0cef556;p=inkscape.git diff --git a/src/display/pixblock-scaler.cpp b/src/display/pixblock-scaler.cpp index c5acaace0..511104c43 100644 --- a/src/display/pixblock-scaler.cpp +++ b/src/display/pixblock-scaler.cpp @@ -15,7 +15,9 @@ #include using std::floor; +#include "display/nr-filter-utils.h" #include "libnr/nr-pixblock.h" +#include "libnr/nr-blit.h" namespace NR { @@ -33,7 +35,7 @@ struct RGBA { * decimal part. (24.8 assuming 32-bit int) */ __attribute__ ((const)) -inline int sampley(unsigned const char a, unsigned const char b, +inline static int sampley(unsigned const char a, unsigned const char b, unsigned const char c, unsigned const char d, const double len) { @@ -61,16 +63,16 @@ inline int sampley(unsigned const char a, unsigned const char b, * Returns the interpolated value in 8-bit format, ready to be written * to output buffer. */ -inline unsigned char samplex(const int a, const int b, const int c, const int d, const double len) { +inline static int samplex(const int a, const int b, const int c, const int d, const double len) { double lenf = len - floor(len); int sum = 0; sum += (int)(a * (((-1.0 / 3.0) * lenf + 4.0 / 5.0) * lenf - 7.0 / 15.0) * lenf); sum += (int)(b * (((lenf - 9.0 / 5.0) * lenf - 1.0 / 5.0) * lenf + 1.0)); sum += (int)(c * ((((1 - lenf) - 9.0 / 5.0) * (1 - lenf) - 1.0 / 5.0) * (1 - lenf) + 1.0)); sum += (int)(d * (((-1.0 / 3.0) * (1 - lenf) + 4.0 / 5.0) * (1 - lenf) - 7.0 / 15.0) * (1 - lenf)); - if (sum < 0) sum = 0; - if (sum >= 256*256) sum = 255 * 256; - return (unsigned char)(sum / 256); + //if (sum < 0) sum = 0; + //if (sum > 255 * 256) sum = 255 * 256; + return sum / 256; } /** @@ -78,7 +80,7 @@ inline unsigned char samplex(const int a, const int b, const int c, const int d, * Catches reading and writing outside the pixblock area. * When enabled, decreases filter rendering speed massively. */ -inline void _check_index(NRPixBlock const * const pb, int const location, int const line) +inline static void _check_index(NRPixBlock const * const pb, int const location, int const line) { if(false) { int max_loc = pb->rs * (pb->area.y1 - pb->area.y0); @@ -87,13 +89,22 @@ inline void _check_index(NRPixBlock const * const pb, int const location, int co } } -void scale_bicubic(NRPixBlock *to, NRPixBlock *from) +static void scale_bicubic_rgba(NRPixBlock *to, NRPixBlock *from) { if (NR_PIXBLOCK_BPP(from) != 4 || NR_PIXBLOCK_BPP(to) != 4) { - g_warning("A non-32-bpp image passed to scale_bicubic: scaling aborted."); + g_warning("A non-32-bpp image passed to scale_bicubic_rgba: scaling aborted."); return; } + bool free_from_on_exit = false; + if (from->mode != to->mode){ + NRPixBlock *o_from = from; + from = new NRPixBlock; + nr_pixblock_setup_fast(from, to->mode, o_from->area.x0, o_from->area.y0, o_from->area.x1, o_from->area.y1, false); + nr_blit_pixblock_pixblock(from, o_from); + free_from_on_exit = true; + } + // Precalculate sizes of source and destination pixblocks int from_width = from->area.x1 - from->area.x0; int from_height = from->area.y1 - from->area.y0; @@ -169,12 +180,110 @@ void scale_bicubic(NRPixBlock *to, NRPixBlock *from) from_x); _check_index(to, to_y * to->rs + to_x * 4, __LINE__); - NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4] = result.r; - NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4 + 1] = result.g; - NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4 + 2] = result.b; - NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4 + 3] = result.a; + + using Inkscape::Filters::clamp; + using Inkscape::Filters::clamp_alpha; + if (to->mode == NR_PIXBLOCK_MODE_R8G8B8A8P) { + /* Clamp the colour channels to range from 0 to result.a to + * make sure, we don't exceed 100% per colour channel with + * images that have premultiplied alpha */ + + result.a = clamp(result.a); + + NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4] = clamp_alpha(result.r, result.a); + NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4 + 1] = clamp_alpha(result.g, result.a); + NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4 + 2] = clamp_alpha(result.b, result.a); + NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4 + 3] = result.a; + } else { + NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4] = clamp(result.r); + NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4 + 1] = clamp(result.g); + NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4 + 2] = clamp(result.b); + NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x * 4 + 3] = clamp(result.a); + } } } + if (free_from_on_exit) { + nr_pixblock_release(from); + delete from; + } + +} + +void scale_bicubic_alpha(NRPixBlock *to, NRPixBlock *from) +{ + if (NR_PIXBLOCK_BPP(from) != 1 || NR_PIXBLOCK_BPP(to) != 1) { + g_warning("A non-8-bpp image passed to scale_bicubic_alpha: scaling aborted."); + return; + } + + // Precalculate sizes of source and destination pixblocks + int from_width = from->area.x1 - from->area.x0; + int from_height = from->area.y1 - from->area.y0; + int to_width = to->area.x1 - to->area.x0; + int to_height = to->area.y1 - to->area.y0; + + // from_step: when advancing one pixel in destination image, + // how much we should advance in source image + double from_stepx = (double)from_width / (double)to_width; + double from_stepy = (double)from_height / (double)to_height; + + // Loop through every pixel of destination image, a line at a time + for (int to_y = 0 ; to_y < to_height ; to_y++) { + double from_y = to_y * from_stepy + from_stepy / 2; + // Pre-calculate beginning of the four horizontal lines, from + // which we should read + int from_line[4]; + for (int i = 0 ; i < 4 ; i++) { + if ((int)floor(from_y) + i - 1 >= 0) { + if ((int)floor(from_y) + i - 1 < from_height) { + from_line[i] = ((int)floor(from_y) + i - 1) * from->rs; + } else { + from_line[i] = (from_height - 1) * from->rs; + } + } else { + from_line[i] = 0; + } + } + // Loop through this horizontal line in destination image + // For every pixel, calculate the color of pixel with + // bicubic interpolation and set the pixel value in destination image + for (int to_x = 0 ; to_x < to_width ; to_x++) { + double from_x = to_x * from_stepx + from_stepx / 2; + int line[4]; + for (int i = 0 ; i < 4 ; i++) { + int k = (int)floor(from_x) + i - 1; + if (k < 0) k = 0; + if (k >= from_width) k = from_width - 1; + _check_index(from, from_line[0] + k, __LINE__); + _check_index(from, from_line[1] + k, __LINE__); + _check_index(from, from_line[2] + k, __LINE__); + _check_index(from, from_line[3] + k, __LINE__); + line[i] = sampley(NR_PIXBLOCK_PX(from)[from_line[0] + k], + NR_PIXBLOCK_PX(from)[from_line[1] + k], + NR_PIXBLOCK_PX(from)[from_line[2] + k], + NR_PIXBLOCK_PX(from)[from_line[3] + k], + from_y); + } + int result; + result = samplex(line[0], line[1], line[2], line[3], + from_x); + + _check_index(to, to_y * to->rs + to_x, __LINE__); + + NR_PIXBLOCK_PX(to)[to_y * to->rs + to_x] = Inkscape::Filters::clamp(result); + } + } +} + +void scale_bicubic(NRPixBlock *to, NRPixBlock *from) +{ + if (NR_PIXBLOCK_BPP(to) == 4 && NR_PIXBLOCK_BPP(from) == 4) { + scale_bicubic_rgba(to, from); + } else if (NR_PIXBLOCK_BPP(to) == 1 && NR_PIXBLOCK_BPP(from) == 1) { + scale_bicubic_alpha(to, from); + } else { + g_warning("NR::scale_bicubic: unsupported bitdepths for scaling: to %d, from %d", NR_PIXBLOCK_BPP(to), NR_PIXBLOCK_BPP(from)); + } } } /* namespace NR */