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http://source.netsurf-browser.org/?view=rev&revision=9027
Stop utterly insane palette entry population.
Palette entries are always ABGR, regardless of platform endianness.
This change probably breaks big-endian platforms which, under the old approach,
had palette entries of the form RGBA (assuming I understood the code correctly).
http://source.netsurf-browser.org/?view=rev&revision=9138
Fix palette entry population some more. Hopefully, it's completely endian
agnostic now and still builds with GCC 4.4
--- libnsgif/src/libnsgif.c 2009/03/29 01:43:27 6984
+++ libnsgif/src/libnsgif.c 2009/08/09 22:24:14 9138
@@ -319,19 +319,34 @@
return GIF_INSUFFICIENT_DATA;
}
for (index = 0; index < gif->colour_table_size; index++) {
- char colour[] = {0, 0, 0, (char)0xff};
- colour[0] = gif_data[0];
- colour[1] = gif_data[1];
- colour[2] = gif_data[2];
- gif->global_colour_table[index] = *((int *) (void *) colour);
+ /* Gif colour map contents are r,g,b.
+ *
+ * We want to pack them bytewise into the
+ * colour table, such that the red component
+ * is in byte 0 and the alpha component is in
+ * byte 3.
+ */
+ unsigned char *entry = (unsigned char *) &gif->
+ global_colour_table[index];
+
+ entry[0] = gif_data[0]; /* r */
+ entry[1] = gif_data[1]; /* g */
+ entry[2] = gif_data[2]; /* b */
+ entry[3] = 0xff; /* a */
+
gif_data += 3;
}
gif->buffer_position = (gif_data - gif->gif_data);
} else {
/* Create a default colour table with the first two colours as black and white
*/
- gif->global_colour_table[0] = 0xff000000;
- gif->global_colour_table[1] = 0xffffffff;
+ unsigned int *entry = gif->global_colour_table;
+
+ entry[0] = 0x00000000;
+ /* Force Alpha channel to opaque */
+ ((unsigned char *) entry)[3] = 0xff;
+
+ entry[1] = 0xffffffff;
}
}
@@ -844,11 +859,21 @@
colour_table = gif->local_colour_table;
if (!clear_image) {
for (index = 0; index < colour_table_size; index++) {
- char colour[] = {0, 0, 0, (char)0xff};
- colour[0] = gif_data[0];
- colour[1] = gif_data[1];
- colour[2] = gif_data[2];
- colour_table[index] = *((int *) (void *) colour);
+ /* Gif colour map contents are r,g,b.
+ *
+ * We want to pack them bytewise into the
+ * colour table, such that the red component
+ * is in byte 0 and the alpha component is in
+ * byte 3.
+ */
+ unsigned char *entry =
+ (unsigned char *) &colour_table[index];
+
+ entry[0] = gif_data[0]; /* r */
+ entry[1] = gif_data[1]; /* g */
+ entry[2] = gif_data[2]; /* b */
+ entry[3] = 0xff; /* a */
+
gif_data += 3;
}
} else {
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