Fixed bug 4798 - PNG w/transparency breaks in SDL 2.0.10 but works in SDL 2.0.9

This commit is contained in:
Sylvain Becker 2019-09-10 17:12:34 +02:00
parent 32bb8b4b40
commit 79e388bfd8
1 changed files with 20 additions and 1 deletions

View File

@ -959,6 +959,8 @@ SDL_ConvertSurface(SDL_Surface * surface, const SDL_PixelFormat * format,
SDL_Color copy_color;
SDL_Rect bounds;
int ret;
int palette_ck_transform = 0;
int palette_ck_value = 0;
if (!surface) {
SDL_InvalidParamError("surface");
@ -1019,8 +1021,23 @@ SDL_ConvertSurface(SDL_Surface * surface, const SDL_PixelFormat * format,
bounds.y = 0;
bounds.w = surface->w;
bounds.h = surface->h;
/* Transform colorkey to alpha. for cases where source palette has duplicate values, and colorkey is one of them */
if (copy_flags & SDL_COPY_COLORKEY) {
if (surface->format->palette && !format->palette) {
palette_ck_transform = 1;
palette_ck_value = surface->format->palette->colors[surface->map->info.colorkey].a;
surface->format->palette->colors[surface->map->info.colorkey].a = SDL_ALPHA_TRANSPARENT;
}
}
ret = SDL_LowerBlit(surface, &bounds, convert, &bounds);
/* Restore value */
if (palette_ck_transform) {
surface->format->palette->colors[surface->map->info.colorkey].a = palette_ck_value;
}
/* Clean up the original surface, and update converted surface */
convert->map->info.r = copy_color.r;
convert->map->info.g = copy_color.g;
@ -1055,7 +1072,9 @@ SDL_ConvertSurface(SDL_Surface * surface, const SDL_PixelFormat * format,
surface->format->palette->ncolors * sizeof(SDL_Color)) == 0)) {
/* The palette is identical, just set the same colorkey */
SDL_SetColorKey(convert, 1, surface->map->info.colorkey);
} else if (format->Amask) {
} else if (!format->palette) {
/* Was done by 'palette_ck_transform' */
}else if (format->Amask) {
set_colorkey_by_color = SDL_TRUE;
ignore_alpha = SDL_FALSE;
} else {