+/* alpha.c
+
+ Part of the swftools package.
+
+ Copyright (c) 2010 Matthias Kramm <kramm@quiss.org>
+
+ 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
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program 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 General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
+
+#include <stdlib.h>
+#include <memory.h>
+#include "../gfxfilter.h"
+#include "../gfxtools.h"
+#include "../types.h"
+#include "../mem.h"
+
+typedef struct _internal {
+ U8 alpha;
+} internal_t;
+
+static inline gfxcolor_t transform_color(internal_t*i, gfxcolor_t*col)
+{
+ gfxcolor_t col2;
+ col2.r = col->r;
+ col2.g = col->g;
+ col2.b = col->b;
+ col2.a = (col->a * i->alpha)/255;
+ return col2;
+}
+
+static void maketransparent_stroke(gfxfilter_t*f, gfxline_t*line, gfxcoord_t width, gfxcolor_t*color, gfx_capType cap_style, gfx_joinType joint_style, gfxcoord_t miterLimit, gfxdevice_t*out)
+{
+ internal_t*i = (internal_t*)f->internal;
+ gfxcolor_t color2 = transform_color(i, color);
+ out->stroke(out, line, width, &color2, cap_style, joint_style, miterLimit);
+}
+static void maketransparent_fill(gfxfilter_t*f, gfxline_t*line, gfxcolor_t*color, gfxdevice_t*out)
+{
+ internal_t*i = (internal_t*)f->internal;
+ gfxcolor_t color2 = transform_color(i, color);
+ out->fill(out, line, &color2);
+}
+static void maketransparent_fillbitmap(gfxfilter_t*f, gfxline_t*line, gfximage_t*img, gfxmatrix_t*matrix, gfxcxform_t*cxform, gfxdevice_t*out)
+{
+ internal_t*i = (internal_t*)f->internal;
+ gfximage_t img2;
+ img2.width = img->width;
+ img2.height = img->height;
+ img2.data = (gfxcolor_t*)rfx_alloc(img->width*img->height*4);
+ int x,y;
+ for(y=0;y<img->height;y++) {
+ gfxcolor_t*in = &img->data[y*img->width];
+ gfxcolor_t*out = &img2.data[y*img->width];
+ for(x=0;x<img->width;x++) {
+ out[x] = transform_color(i, &in[x]);
+ }
+ }
+ out->fillbitmap(out, line, &img2, matrix, cxform);
+ rfx_free(img2.data);
+}
+static void maketransparent_drawchar(gfxfilter_t*f, gfxfont_t*font, int glyphnr, gfxcolor_t*color, gfxmatrix_t*matrix, gfxdevice_t*out)
+{
+ internal_t*i = (internal_t*)f->internal;
+ gfxcolor_t color2 = transform_color(i, color);
+ out->drawchar(out, font, glyphnr, color, matrix);
+}
+static void maketransparent_fillgradient(gfxfilter_t*f, gfxline_t*line, gfxgradient_t*gradient, gfxgradienttype_t type, gfxmatrix_t*matrix, gfxdevice_t*out)
+{
+ internal_t*i = (internal_t*)f->internal;
+
+ gfxgradient_t*g = 0, *prev = 0;
+
+ while(gradient) {
+ gfxgradient_t*n = rfx_alloc(sizeof(gfxgradient_t));
+ n->pos = gradient->pos;
+ n->color = transform_color(i, &gradient->color);
+ n->next = 0;
+ if(prev) {
+ prev->next = n;
+ prev = n;
+ } else {
+ g = prev = n;
+ }
+ gradient = gradient->next;
+ }
+
+ out->fillgradient(out, line, g, type, matrix);
+ gfxgradient_destroy(g);
+}
+
+void gfxfilter_maketransparent(gfxfilter_t*f, U8 alpha)
+{
+ internal_t*i = (internal_t*)rfx_calloc(sizeof(internal_t));
+ i->alpha = alpha;
+
+ memset(f, 0, sizeof(gfxfilter_t));
+ f->name = "maketransparent";
+ f->internal = i;
+ f->stroke = maketransparent_stroke;
+ f->fill = maketransparent_fill;
+ f->fillbitmap = maketransparent_fillbitmap;
+ f->fillgradient = maketransparent_fillgradient;
+ f->drawchar = maketransparent_drawchar;
+}
+