--- /dev/null
+/*
+ * art_rgba.c: Functions for manipulating RGBA pixel data.
+ *
+ * Libart_LGPL - library of basic graphic primitives
+ * Copyright (C) 2000 Raph Levien
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Library General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+#include "config.h"
+#include "art_rgba.h"
+
+#define ART_OPTIMIZE_SPACE
+
+#ifndef ART_OPTIMIZE_SPACE
+#include "art_rgba_table.c"
+#endif
+
+/**
+ * art_rgba_rgba_composite: Composite RGBA image over RGBA buffer.
+ * @dst: Destination RGBA buffer.
+ * @src: Source RGBA buffer.
+ * @n: Number of RGBA pixels to composite.
+ *
+ * Composites the RGBA pixels in @dst over the @src buffer.
+ **/
+void
+art_rgba_rgba_composite (art_u8 *dst, const art_u8 *src, int n)
+{
+ int i;
+#ifdef WORDS_BIGENDIAN
+ art_u32 src_rgba, dst_rgba;
+#else
+ art_u32 src_abgr, dst_abgr;
+#endif
+ art_u8 src_alpha, dst_alpha;
+
+ for (i = 0; i < n; i++)
+ {
+#ifdef WORDS_BIGENDIAN
+ src_rgba = ((art_u32 *)src)[i];
+ src_alpha = src_rgba & 0xff;
+#else
+ src_abgr = ((art_u32 *)src)[i];
+ src_alpha = (src_abgr >> 24) & 0xff;
+#endif
+ if (src_alpha)
+ {
+ if (src_alpha == 0xff ||
+ (
+#ifdef WORDS_BIGENDIAN
+ dst_rgba = ((art_u32 *)dst)[i],
+ dst_alpha = dst_rgba & 0xff,
+#else
+ dst_abgr = ((art_u32 *)dst)[i],
+ dst_alpha = (dst_abgr >> 24),
+#endif
+ dst_alpha == 0))
+#ifdef WORDS_BIGENDIAN
+ ((art_u32 *)dst)[i] = src_rgba;
+#else
+ ((art_u32 *)dst)[i] = src_abgr;
+#endif
+ else
+ {
+ int r, g, b, a;
+ int src_r, src_g, src_b;
+ int dst_r, dst_g, dst_b;
+ int tmp;
+ int c;
+
+#ifdef ART_OPTIMIZE_SPACE
+ tmp = (255 - src_alpha) * (255 - dst_alpha) + 0x80;
+ a = 255 - ((tmp + (tmp >> 8)) >> 8);
+ c = ((src_alpha << 16) + (a >> 1)) / a;
+#else
+ tmp = art_rgba_composite_table[(src_alpha << 8) + dst_alpha];
+ c = tmp & 0x1ffff;
+ a = tmp >> 24;
+#endif
+#ifdef WORDS_BIGENDIAN
+ src_r = (src_rgba >> 24) & 0xff;
+ src_g = (src_rgba >> 16) & 0xff;
+ src_b = (src_rgba >> 8) & 0xff;
+ dst_r = (dst_rgba >> 24) & 0xff;
+ dst_g = (dst_rgba >> 16) & 0xff;
+ dst_b = (dst_rgba >> 8) & 0xff;
+#else
+ src_r = src_abgr & 0xff;
+ src_g = (src_abgr >> 8) & 0xff;
+ src_b = (src_abgr >> 16) & 0xff;
+ dst_r = dst_abgr & 0xff;
+ dst_g = (dst_abgr >> 8) & 0xff;
+ dst_b = (dst_abgr >> 16) & 0xff;
+#endif
+ r = dst_r + (((src_r - dst_r) * c + 0x8000) >> 16);
+ g = dst_g + (((src_g - dst_g) * c + 0x8000) >> 16);
+ b = dst_b + (((src_b - dst_b) * c + 0x8000) >> 16);
+#ifdef WORDS_BIGENDIAN
+ ((art_u32 *)dst)[i] = (r << 24) | (g << 16) | (b << 8) | a;
+#else
+ ((art_u32 *)dst)[i] = (a << 24) | (b << 16) | (g << 8) | r;
+#endif
+ }
+ }
+#if 0
+ /* it's not clear to me this optimization really wins */
+ else
+ {
+ /* skip over run of transparent pixels */
+ for (; i < n - 1; i++)
+ {
+#ifdef WORDS_BIGENDIAN
+ src_rgba = ((art_u32 *)src)[i + 1];
+ if (src_rgba & 0xff)
+ break;
+#else
+ src_abgr = ((art_u32 *)src)[i + 1];
+ if (src_abgr & 0xff000000)
+ break;
+#endif
+ }
+ }
+#endif
+ }
+}
+
+/**
+ * art_rgba_fill_run: fill an RGBA buffer a solid RGB color.
+ * @buf: Buffer to fill.
+ * @r: Red, range 0..255.
+ * @g: Green, range 0..255.
+ * @b: Blue, range 0..255.
+ * @n: Number of RGB triples to fill.
+ *
+ * Fills a buffer with @n copies of the (@r, @g, @b) triple, solid
+ * alpha. Thus, locations @buf (inclusive) through @buf + 4 * @n
+ * (exclusive) are written.
+ **/
+void
+art_rgba_fill_run (art_u8 *buf, art_u8 r, art_u8 g, art_u8 b, int n)
+{
+ int i;
+#ifdef WORDS_BIGENDIAN
+ art_u32 src_rgba;
+#else
+ art_u32 src_abgr;
+#endif
+
+#ifdef WORDS_BIGENDIAN
+ src_rgba = (r << 24) | (g << 16) | (b << 8) | 255;
+#else
+ src_abgr = (255 << 24) | (b << 16) | (g << 8) | r;
+#endif
+ for (i = 0; i < n; i++)
+ {
+#ifdef WORDS_BIGENDIAN
+ ((art_u32 *)buf)[i] = src_rgba;
+#else
+ ((art_u32 *)buf)[i] = src_abgr;
+#endif
+ }
+}
+
+/**
+ * art_rgba_run_alpha: Render semitransparent color over RGBA buffer.
+ * @buf: Buffer for rendering.
+ * @r: Red, range 0..255.
+ * @g: Green, range 0..255.
+ * @b: Blue, range 0..255.
+ * @alpha: Alpha, range 0..255.
+ * @n: Number of RGB triples to render.
+ *
+ * Renders a sequential run of solid (@r, @g, @b) color over @buf with
+ * opacity @alpha. Note that the range of @alpha is 0..255, in contrast
+ * to art_rgb_run_alpha, which has a range of 0..256.
+ **/
+void
+art_rgba_run_alpha (art_u8 *buf, art_u8 r, art_u8 g, art_u8 b, int alpha, int n)
+{
+ int i;
+#ifdef WORDS_BIGENDIAN
+ art_u32 src_rgba, dst_rgba;
+#else
+ art_u32 src_abgr, dst_abgr;
+#endif
+ art_u8 dst_alpha;
+ int a;
+ int dst_r, dst_g, dst_b;
+ int tmp;
+ int c;
+
+#ifdef WORDS_BIGENDIAN
+ src_rgba = (r << 24) | (g << 16) | (b << 8) | alpha;
+#else
+ src_abgr = (alpha << 24) | (b << 16) | (g << 8) | r;
+#endif
+ for (i = 0; i < n; i++)
+ {
+#ifdef WORDS_BIGENDIAN
+ dst_rgba = ((art_u32 *)buf)[i];
+ dst_alpha = dst_rgba & 0xff;
+#else
+ dst_abgr = ((art_u32 *)buf)[i];
+ dst_alpha = (dst_abgr >> 24) & 0xff;
+#endif
+ if (dst_alpha)
+ {
+#ifdef ART_OPTIMIZE_SPACE
+ tmp = (255 - alpha) * (255 - dst_alpha) + 0x80;
+ a = 255 - ((tmp + (tmp >> 8)) >> 8);
+ c = ((alpha << 16) + (a >> 1)) / a;
+#else
+ tmp = art_rgba_composite_table[(alpha << 8) + dst_alpha];
+ c = tmp & 0x1ffff;
+ a = tmp >> 24;
+#endif
+#ifdef WORDS_BIGENDIAN
+ dst_r = (dst_rgba >> 24) & 0xff;
+ dst_g = (dst_rgba >> 16) & 0xff;
+ dst_b = (dst_rgba >> 8) & 0xff;
+#else
+ dst_r = dst_abgr & 0xff;
+ dst_g = (dst_abgr >> 8) & 0xff;
+ dst_b = (dst_abgr >> 16) & 0xff;
+#endif
+ dst_r += (((r - dst_r) * c + 0x8000) >> 16);
+ dst_g += (((g - dst_g) * c + 0x8000) >> 16);
+ dst_b += (((b - dst_b) * c + 0x8000) >> 16);
+#ifdef WORDS_BIGENDIAN
+ ((art_u32 *)buf)[i] = (dst_r << 24) | (dst_g << 16) | (dst_b << 8) | a;
+#else
+ ((art_u32 *)buf)[i] = (a << 24) | (dst_b << 16) | (dst_g << 8) | dst_r;
+#endif
+ }
+ else
+ {
+#ifdef WORDS_BIGENDIAN
+ ((art_u32 *)buf)[i] = src_rgba;
+#else
+ ((art_u32 *)buf)[i] = src_abgr;
+#endif
+ }
+ }
+}
git.asbjorn.biz / swftools.git / blobdiff