Revert "video: Optimize temporarily saving of dest alpha for a blit."

This reverts commit 812d58fb1de30bb94dd89f76e838f1884284bcc1.
Bisection indicates that this triggers a crash in the amoebax package.

Bug: https://github.com/libsdl-org/sdl12-compat/issues/211

Gbp-Pq: Name Revert-video-Optimize-temporarily-saving-of-dest-alpha-fo.patch

1 files changed, 8 insertions, 12 deletions

diff --git a/src/SDL12_compat.c b/src/SDL12_compat.c
index 2dddc16..812f7d4 100644
--- a/src/SDL12_compat.c
+++ b/src/SDL12_compat.c
@@ -6041,7 +6041,7 @@ SDL_GetVideoSurface(void)
 }
 
 static int
-SaveDestAlpha(SDL12_Surface *src12, SDL12_Surface *dst12, const SDL12_Rect *dstrect12, Uint8 **retval)
+SaveDestAlpha(SDL12_Surface *src12, SDL12_Surface *dst12, Uint8 **retval)
 {
     /* The 1.2 docs say this:
      * RGBA->RGBA:
@@ -6058,8 +6058,8 @@ SaveDestAlpha(SDL12_Surface *src12, SDL12_Surface *dst12, const SDL12_Rect *dstr
         Uint8 *dptr;
         int x, y;
 
-        const int w = dstrect12->w;
-        const int h = dstrect12->h;
+        const int w = dst12->w;
+        const int h = dst12->h;
 
         const Uint32 amask = dst12->format->Amask;
         const Uint32 ashift = dst12->format->Ashift;
@@ -6074,7 +6074,6 @@ SaveDestAlpha(SDL12_Surface *src12, SDL12_Surface *dst12, const SDL12_Rect *dstr
 
         if (dst12->format->BytesPerPixel == 2) {
             const Uint16 *sptr = (const Uint16 *) dst12->pixels;
-            sptr += ((dst12->pitch / 2) * dstrect12->y) + dstrect12->x;
             for (y = 0; y < h; y++) {
                 for (x = 0; x < w; x++) {
                     *(dptr++) = (Uint8) ((sptr[x] & amask) >> ashift);
@@ -6083,7 +6082,6 @@ SaveDestAlpha(SDL12_Surface *src12, SDL12_Surface *dst12, const SDL12_Rect *dstr
             }
         } else if (dst12->format->BytesPerPixel == 4) {
             const Uint32 *sptr = (const Uint32 *) dst12->pixels;
-            sptr += ((dst12->pitch / 4) * dstrect12->y) + dstrect12->x;
             for (y = 0; y < h; y++) {
                 for (x = 0; x < w; x++) {
                     *(dptr++) = (Uint8) ((sptr[x] & amask) >> ashift);
@@ -6100,7 +6098,7 @@ SaveDestAlpha(SDL12_Surface *src12, SDL12_Surface *dst12, const SDL12_Rect *dstr
 }
 
 static void
-RestoreDestAlpha(SDL12_Surface *dst12, Uint8 *dstalpha, const SDL12_Rect *dstrect12)
+RestoreDestAlpha(SDL12_Surface *dst12, Uint8 *dstalpha)
 {
     if (dstalpha) {
         int x, y;
@@ -6114,7 +6112,6 @@ RestoreDestAlpha(SDL12_Surface *dst12, Uint8 *dstalpha, const SDL12_Rect *dstrec
 
         if (dst12->format->BytesPerPixel == 2) {
             Uint16 *dptr = (Uint16 *) dst12->pixels;
-            dptr += ((dst12->pitch / 2) * dstrect12->y) + dstrect12->x;
             for (y = 0; y < h; y++) {
                 for (x = 0; x < w; x++) {
                     dptr[x] = (Uint16) ((dptr[x] & ~amask) | ((((Uint16) *(sptr++)) << ashift) & amask));
@@ -6123,7 +6120,6 @@ RestoreDestAlpha(SDL12_Surface *dst12, Uint8 *dstalpha, const SDL12_Rect *dstrec
             }
         } else if (dst12->format->BytesPerPixel == 4) {
             Uint32 *dptr = (Uint32 *) dst12->pixels;
-            dptr += ((dst12->pitch / 4) * dstrect12->y) + dstrect12->x;
             for (y = 0; y < h; y++) {
                 for (x = 0; x < w; x++) {
                     dptr[x] = (dptr[x] & ~amask) | ((((Uint32) *(sptr++)) << ashift) & amask);
@@ -6146,7 +6142,7 @@ SDL_UpperBlit(SDL12_Surface *src12, SDL12_Rect *srcrect12, SDL12_Surface *dst12,
 
     if ((src12 == NULL) || (dst12 == NULL)) {
         return SDL20_SetError("SDL_UpperBlit: passed a NULL surface");
-    } else if (SaveDestAlpha(src12, dst12, dstrect12, &dstalpha) < 0) {
+    } else if (SaveDestAlpha(src12, dst12, &dstalpha) < 0) {
         return -1;
     }
 
@@ -6155,7 +6151,7 @@ SDL_UpperBlit(SDL12_Surface *src12, SDL12_Rect *srcrect12, SDL12_Surface *dst12,
                              dst12->surface20,
                              dstrect12 ? Rect12to20(dstrect12, &dstrect20) : NULL);
 
-    RestoreDestAlpha(dst12, dstalpha, dstrect12);
+    RestoreDestAlpha(dst12, dstalpha);
 
     if (dstrect12) {
         Rect20to12(&dstrect20, dstrect12);
@@ -6171,7 +6167,7 @@ SDL_LowerBlit(SDL12_Surface *src12, SDL12_Rect *srcrect12, SDL12_Surface *dst12,
     SDL_Rect srcrect20, dstrect20;
     int retval;
 
-    if (SaveDestAlpha(src12, dst12, dstrect12, &dstalpha) < 0) {
+    if (SaveDestAlpha(src12, dst12, &dstalpha) < 0) {
         return -1;
     }
 
@@ -6180,7 +6176,7 @@ SDL_LowerBlit(SDL12_Surface *src12, SDL12_Rect *srcrect12, SDL12_Surface *dst12,
                              dst12->surface20,
                              dstrect12 ? Rect12to20(dstrect12, &dstrect20) : NULL);
 
-    RestoreDestAlpha(dst12, dstalpha, dstrect12);
+    RestoreDestAlpha(dst12, dstalpha);
 
     if (srcrect12) {
         Rect20to12(&srcrect20, srcrect12);