added mode 2 transparency support

[swftools.git] / lib / png.c

diff --git a/lib/png.c b/lib/png.c
index abb5a3e..49c3c3d 100644 (file)
--- a/lib/png.c
+++ b/lib/png.c
@@ -634,10 +634,22 @@ int getPNG(char*sname, int*destwidth, int*destheight, unsigned char**destdata)
            } else {
                old = &data2[(y-1)*header.width*4];
            }
-           if(header.mode == 6)
+           if(header.mode == 6) {
                applyfilter4(mode, src, old, dest, header.width);
-           else // header.mode = 2
+           } else { // header.mode = 2
                applyfilter3(mode, src, old, dest, header.width);
+               /* replace alpha color */
+               if(hasalphacolor) {
+                   int x;
+                   for(x=0;x<header.width;x++) {
+                       if(dest[x*4+1] == alphacolor[0] &&
+                          dest[x*4+2] == alphacolor[1] &&
+                          dest[x*4+3] == alphacolor[2]) {
+                           *(U32*)&dest[x*4] = 0;
+                       }
+                   }
+               }
+           }
        }
         free(imagedata);
     } else if(header.mode == 0 || header.mode == 3) {