arithmetic. The routine below is shamelessly, gloriously
floating point. TBB */
-void
-gdImageCopyResampled (gdImagePtr dst,
- gdImagePtr src,
- int dstX, int dstY,
- int srcX, int srcY,
- int dstW, int dstH,
- int srcW, int srcH)
+void gdImageCopyResampled (gdImagePtr dst, gdImagePtr src, int dstX, int dstY, int srcX, int srcY, int dstW, int dstH, int srcW, int srcH)
{
- int x, y;
- if (!dst->trueColor)
- {
- gdImageCopyResized (
- dst, src, dstX, dstY, srcX, srcY, dstW, dstH,
- srcW, srcH);
- return;
- }
- for (y = dstY; (y < dstY + dstH); y++)
- {
- for (x = dstX; (x < dstX + dstW); x++)
- {
- float sy1, sy2, sx1, sx2;
- float sx, sy;
- float spixels = 0;
- float red = 0.0, green = 0.0, blue = 0.0, alpha = 0.0, alpha_sum = 0.0, contrib_sum = 0.0, alpha_factor;
- sy1 = ((float) y - (float) dstY) * (float) srcH /
- (float) dstH;
- sy2 = ((float) (y + 1) - (float) dstY) * (float) srcH /
- (float) dstH;
- sy = sy1;
- do
- {
- float yportion;
- if (floorf (sy) == floorf (sy1))
- {
- yportion = 1.0f - (sy - floorf (sy));
- if (yportion > sy2 - sy1)
- {
- yportion = sy2 - sy1;
- }
- sy = floorf (sy);
- }
- else if (sy == floorf (sy2))
- {
- yportion = sy2 - floorf (sy2);
- }
- else
- {
- yportion = 1.0f;
- }
- sx1 = ((float) x - (float) dstX) * (float) srcW /
- dstW;
- sx2 = ((float) (x + 1) - (float) dstX) * (float) srcW /
- dstW;
- sx = sx1;
- do
- {
- float xportion;
- float pcontribution;
- int p;
- if (floorf (sx) == floorf (sx1))
- {
- xportion = 1.0f - (sx - floorf (sx));
- if (xportion > sx2 - sx1)
- {
- xportion = sx2 - sx1;
+ int x, y;
+ if (!dst->trueColor) {
+ gdImageCopyResized (dst, src, dstX, dstY, srcX, srcY, dstW, dstH, srcW, srcH);
+ return;
+ }
+ for (y = dstY; (y < dstY + dstH); y++) {
+ for (x = dstX; (x < dstX + dstW); x++) {
+ float sy1, sy2, sx1, sx2;
+ float sx, sy;
+ float spixels = 0.0;
+ float red = 0.0, green = 0.0, blue = 0.0, alpha = 0.0;
+ float alpha_factor, alpha_sum = 0.0, contrib_sum = 0.0;
+ sy1 = ((float)(y - dstY)) * (float)srcH / (float)dstH;
+ sy2 = ((float)(y + 1 - dstY)) * (float) srcH / (float) dstH;
+ sy = sy1;
+ do {
+ float yportion;
+ if (floorf(sy) == floorf(sy1)) {
+ yportion = 1.0 - (sy - floorf(sy));
+ if (yportion > sy2 - sy1) {
+ yportion = sy2 - sy1;
+ }
+ sy = floorf(sy);
+ } else if (sy == floorf(sy2)) {
+ yportion = sy2 - floorf(sy2);
+ } else {
+ yportion = 1.0;
+ }
+ sx1 = ((float)(x - dstX)) * (float) srcW / dstW;
+ sx2 = ((float)(x + 1 - dstX)) * (float) srcW / dstW;
+ sx = sx1;
+ do {
+ float xportion;
+ float pcontribution;
+ int p;
+ if (floorf(sx) == floorf(sx1)) {
+ xportion = 1.0 - (sx - floorf(sx));
+ if (xportion > sx2 - sx1) {
+ xportion = sx2 - sx1;
+ }
+ sx = floorf(sx);
+ } else if (sx == floorf(sx2)) {
+ xportion = sx2 - floorf(sx2);
+ } else {
+ xportion = 1.0;
+ }
+ pcontribution = xportion * yportion;
+ p = gdImageGetTrueColorPixel(src, (int) sx + srcX, (int) sy + srcY);
+
+ alpha_factor = ((gdAlphaMax - gdTrueColorGetAlpha(p))) * pcontribution;
+ red += gdTrueColorGetRed (p) * alpha_factor;
+ green += gdTrueColorGetGreen (p) * alpha_factor;
+ blue += gdTrueColorGetBlue (p) * alpha_factor;
+ alpha += gdTrueColorGetAlpha (p) * pcontribution;
+ alpha_sum += alpha_factor;
+ contrib_sum += pcontribution;
+ spixels += xportion * yportion;
+ sx += 1.0;
+ }
+ while (sx < sx2);
+
+ sy += 1.0f;
}
- sx = floorf (sx);
- }
- else if (sx == floorf (sx2))
- {
- xportion = sx2 - floorf (sx2);
- }
- else
- {
- xportion = 1.0f;
- }
- pcontribution = xportion * yportion;
- p = gdImageGetTrueColorPixel (
- src,
- (int) sx,
- (int) sy);
- alpha_factor = ((gdAlphaMax - gdTrueColorGetAlpha(p))) * pcontribution;
- green += gdTrueColorGetGreen (p) * pcontribution;
- red += gdTrueColorGetRed (p) * alpha_factor;
- blue += gdTrueColorGetBlue (p) * pcontribution;
- green += gdTrueColorGetGreen (p) * alpha_factor;
- alpha += gdTrueColorGetAlpha (p) * pcontribution;
- alpha_sum += alpha_factor;
- contrib_sum += pcontribution;
- spixels += xportion * yportion;
- sx += 1.0;
+
+ while (sy < sy2);
+
+ if (spixels != 0.0) {
+ red /= spixels;
+ green /= spixels;
+ blue /= spixels;
+ alpha /= spixels;
+ }
+ if ( alpha_sum != 0.0) {
+ if( contrib_sum != 0.0) {
+ alpha_sum /= contrib_sum;
+ }
+ red /= alpha_sum;
+ green /= alpha_sum;
+ blue /= alpha_sum;
+ }
+ /* Clamping to allow for rounding errors above */
+ if (red > 255.0) {
+ red = 255.0;
+ }
+ if (green > 255.0) {
+ green = 255.0;
+ }
+ if (blue > 255.0f) {
+ blue = 255.0;
+ }
+ if (alpha > gdAlphaMax) {
+ alpha = gdAlphaMax;
+ }
+ gdImageSetPixel(dst, x, y, gdTrueColorAlpha ((int) red, (int) green, (int) blue, (int) alpha));
}
- while (sx < sx2);
- sy += 1.0;
- }
- while (sy < sy2);
- if (spixels != 0.0)
- {
- red /= spixels;
- green /= spixels;
- blue /= spixels;
- alpha /= spixels;
- }
- if ( alpha_sum != 0.0)
- {
- if( contrib_sum != 0.0 ) alpha_sum /= contrib_sum;
- red /= alpha_sum;
- green /= alpha_sum;
- blue /= alpha_sum;
- }
- /* Clamping to allow for rounding errors above */
- if (red > 255.0)
- {
- red = 255.0;
- }
- if (green > 255.0)
- {
- green = 255.0;
- }
- if (blue > 255.0)
- {
- blue = 255.0;
- }
- if (alpha > gdAlphaMax)
- {
- alpha = gdAlphaMax;
- }
- gdImageSetPixel (dst,
- x, y,
- gdTrueColorAlpha ((int) red,
- (int) green,
- (int) blue,
- (int) alpha));
}
- }
}
+
#ifdef ROTATE_PI
#undef ROTATE_PI
#endif /* ROTATE_PI */
projects / php / commitdiff