/* -*- indent-tabs-mode: nil; tab-width: 4; c-basic-offset: 4; -*-
image.c for the Openbox window manager
- Copyright (c) 2003 Ben Jansens
+ Copyright (c) 2006 Mikael Magnusson
+ Copyright (c) 2003-2007 Dana Jansens
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
#include <glib.h>
-#define AVERAGE(a, b) ( ((((a) ^ (b)) & 0xfefefefeL) >> 1) + ((a) & (b)) )
+#define FRACTION 12
+#define FLOOR(i) ((i) & (~0UL << FRACTION))
+#define AVERAGE(a, b) (((((a) ^ (b)) & 0xfefefefeL) >> 1) + ((a) & (b)))
-static void scale_line(RrPixel32 *dest, RrPixel32 *source, gint w, gint dw)
+static void ImageCopyResampled(RrPixel32 *dst, RrPixel32 *src,
+ gulong dstW, gulong dstH,
+ gulong srcW, gulong srcH)
{
- gint num_pixels = dw;
- gint int_part = w / dw;
- gint fract_part = w % dw;
- gint err = 0;
-
- while (num_pixels-- > 0) {
- *dest++ = *source;
- source += int_part;
- err += fract_part;
- if (err >= dw) {
- err -= dw;
- source++;
- }
- }
-}
-
-static RrPixel32* scale_half(RrPixel32 *source, gint w, gint h)
-{
- RrPixel32 *out, *dest, *sourceline, *sourceline2;
- gint dw, dh, x, y;
-
- sourceline = source;
- sourceline2 = source + w;
-
- dw = w >> 1;
- dh = h >> 1;
-
- out = dest = g_new(RrPixel32, dw * dh);
-
- for (y = 0; y < dh; ++y) {
- RrPixel32 *s, *s2;
-
- s = sourceline;
- s2 = sourceline2;
-
- for (x = 0; x < dw; ++x) {
- *dest++ = AVERAGE(AVERAGE(*s, *(s+1)),
- AVERAGE(*s2, *(s2+1)));
- s += 2;
- s2 += 2;
- }
- sourceline += w << 1;
- sourceline2 += w << 1;
- }
- return out;
-}
-
-static RrPixel32* scale_rect(RrPixel32 *fullsource,
- gint w, gint h, gint dw, gint dh)
-{
- RrPixel32 *out, *dest;
- RrPixel32 *source = fullsource;
- RrPixel32 *oldsource = NULL;
- RrPixel32 *prev_source = NULL;
- gint num_pixels;
- gint int_part;
- gint fract_part;
- gint err = 0;
-
- while (dw <= (w >> 1) && dh <= (h >> 1)) {
- source = scale_half(source, w, h);
- w >>= 1; h >>= 1;
- g_free(oldsource);
- oldsource = source;
- }
-
- num_pixels = dh;
- int_part = (h / dh) * w;
- fract_part = h % dh;
-
- out = dest = g_new(RrPixel32, dw * dh);
-
- while (num_pixels-- > 0) {
- if (source == prev_source) {
- memcpy(dest, dest - dw, dw * sizeof(RrPixel32));
- } else {
- scale_line(dest, source, w, dw);
- prev_source = source;
- }
- dest += dw;
- source += int_part;
- err += fract_part;
- if (err >= dh) {
- err -= dh;
- source += w;
+ gulong dstX, dstY, srcX, srcY;
+ gulong srcX1, srcX2, srcY1, srcY2;
+ gulong ratioX, ratioY;
+
+ ratioX = (srcW << FRACTION) / dstW;
+ ratioY = (srcH << FRACTION) / dstH;
+
+ srcY2 = 0;
+ for (dstY = 0; dstY < dstH; dstY++) {
+ srcY1 = srcY2;
+ srcY2 += ratioY;
+
+ srcX2 = 0;
+ for (dstX = 0; dstX < dstW; dstX++) {
+ gulong red = 0, green = 0, blue = 0, alpha = 0;
+ gulong portionX, portionY, portionXY, sumXY = 0;
+ RrPixel32 pixel;
+
+ srcX1 = srcX2;
+ srcX2 += ratioX;
+
+ for (srcY = srcY1; srcY < srcY2; srcY += (1UL << FRACTION)) {
+ if (srcY == srcY1) {
+ srcY = FLOOR(srcY);
+ portionY = (1UL << FRACTION) - (srcY1 - srcY);
+ if (portionY > srcY2 - srcY1)
+ portionY = srcY2 - srcY1;
+ }
+ else if (srcY == FLOOR(srcY2))
+ portionY = srcY2 - srcY;
+ else
+ portionY = (1UL << FRACTION);
+
+ for (srcX = srcX1; srcX < srcX2; srcX += (1UL << FRACTION)) {
+ if (srcX == srcX1) {
+ srcX = FLOOR(srcX);
+ portionX = (1UL << FRACTION) - (srcX1 - srcX);
+ if (portionX > srcX2 - srcX1)
+ portionX = srcX2 - srcX1;
+ }
+ else if (srcX == FLOOR(srcX2))
+ portionX = srcX2 - srcX;
+ else
+ portionX = (1UL << FRACTION);
+
+ portionXY = (portionX * portionY) >> FRACTION;
+ sumXY += portionXY;
+
+ pixel = *(src + (srcY >> FRACTION) * srcW
+ + (srcX >> FRACTION));
+ red += ((pixel >> RrDefaultRedOffset) & 0xFF)
+ * portionXY;
+ green += ((pixel >> RrDefaultGreenOffset) & 0xFF)
+ * portionXY;
+ blue += ((pixel >> RrDefaultBlueOffset) & 0xFF)
+ * portionXY;
+ alpha += ((pixel >> RrDefaultAlphaOffset) & 0xFF)
+ * portionXY;
+ }
+ }
+
+ g_assert(sumXY != 0);
+ red /= sumXY;
+ green /= sumXY;
+ blue /= sumXY;
+ alpha /= sumXY;
+
+ *dst++ = (red << RrDefaultRedOffset) |
+ (green << RrDefaultGreenOffset) |
+ (blue << RrDefaultBlueOffset) |
+ (alpha << RrDefaultAlphaOffset);
}
}
-
- g_free(oldsource);
-
- return out;
}
void RrImageDraw(RrPixel32 *target, RrTextureRGBA *rgba,
if (sw != dw || sh != dh) {
/*if (!(rgba->cache && dw == rgba->cwidth && dh == rgba->cheight))*/ {
g_free(rgba->cache);
- rgba->cache = scale_rect(rgba->data, sw, sh, dw, dh);
+ rgba->cache = g_new(RrPixel32, dw * dh);
+ ImageCopyResampled(rgba->cache, rgba->data, dw, dh, sw, sh);
rgba->cwidth = dw;
rgba->cheight = dh;
}
r = *source >> RrDefaultRedOffset;
g = *source >> RrDefaultGreenOffset;
b = *source >> RrDefaultBlueOffset;
-
+
/* background color */
bgr = *dest >> RrDefaultRedOffset;
bgg = *dest >> RrDefaultGreenOffset;
projects / chaz / openbox / blobdiff