Bugzilla Bug 40327

I've found quite annoying bug in PPC version of xmame. The fullscreen xv code
seems not to be endian-aware and because of that when emulator is switched to
xv YUV fullscreen mode everything turns green+pink.

As I really needed to run it in fullscreen I did some investigation and here is
the solution (probably qick and dirty, but working). There are two files that
need patching. First is src/unix/video-drivers/x11_window.c where there is a
YUV lookup table generation code which is not endian-aware. The second is
blit.h where there is a code to convert bitmap using the lookup table into YUV
packed format. And again - this code isn't endian-aware. Below is the patch I
worked out and applied on the xmame-0.78.1 package. After this the emulator
compiles fine on PPC and works as it sholud.

---------- 0.78.1-yuvppc-fix.patch --------------------------------
--- src/unix/video-drivers/x11_window.c 2003-12-27 00:29:16.000000000 +0100
+++ src/unix/video-drivers/x11_window.c 2004-02-03 23:04:22.000000000 +0100
@@ -1463,7 +1463,11 @@

         /* Storing this data in YUYV order simplifies using the data for
            YUY2, both with and without smoothing... */
+#ifdef LSB_FIRST
         hwscale_yuvlookup[i]=(y<<0) | (u<<8) | (y<<16) | (v<<24);
+#else
+        hwscale_yuvlookup[i]=(y<<24) | (u<<16) | (y<<8) | (v<<0);
+#endif
       }
    }
 }
--- src/unix/video-drivers/blit.h       2003-12-27 00:29:16.000000000 +0100
+++ src/unix/video-drivers/blit.h       2004-02-04 01:17:56.000000000 +0100
@@ -72,6 +72,7 @@
    }\
       }
 #elif defined BLIT_HWSCALE_YUY2
+#ifdef LSB_FIRST /* x86 etc */
 #define COPY_LINE2(SRC, END, DST) \
    {\
       SRC_PIXEL  *src = SRC; \
@@ -89,6 +90,25 @@
          *dst++=y|y2|((uv1+uv2)&0xff00ff00);\
       } \
    }
+#else /* ppc etc */
+#define COPY_LINE2(SRC, END, DST) \
+   {\
+      SRC_PIXEL  *src = SRC; \
+      SRC_PIXEL  *end = END; \
+      unsigned long *dst = (unsigned long *)DST; \
+      unsigned int r,y,y2,uv1,uv2; \
+      for(;src<end;) \
+      { \
+         r=INDIRECT[*src++]; \
+         y=r&0xff000000 ; \
+         uv1=(r&0x00ff00ff); \
+         r=INDIRECT[*src++]; \
+         uv2=(uv1+(r&0x00ff00ff))>>1; \
+         y2=r&0xff00; \
+         *dst++=y|y2|(uv2&0x00ff00ff); \
+      } \
+   }
+#endif
 #else /* normal indirect */
 #define COPY_LINE2(SRC, END, DST) \
       {\
@@ -428,24 +448,43 @@
       *(dst+2) = (INDIRECT[*(src+2)]>>16) | (INDIRECT[*(src+3)]<< 8); \
    }
 #elif defined BLIT_HWSCALE_YUY2
+#ifdef LSB_FIRST /* x86 etc */
 #define COPY_LINE2(SRC, END, DST) \
    {\
       SRC_PIXEL  *src = SRC; \
       SRC_PIXEL  *end = END; \
       unsigned long *dst = (unsigned long *)DST; \
-      unsigned int r,r2,y,y2,uv1,uv2; \
+      unsigned int r,y,y2,uv1,uv2; \
       for(;src<end;) \
       { \
          r=INDIRECT[*src++]; \
-         r2=INDIRECT[*src++]; \
-         y=r&0xff; \
-         y2=r2&0xff0000; \
+         y=r&255; \
          uv1=(r&0xff00ff00)>>1; \
-         uv2=(r2&0xff00ff00)>>1; \
-         uv1=(uv1+uv2)&0xff00ff00; \
-         *dst++=y|y2|uv1; \
+         r=INDIRECT[*src++]; \
+         uv2=(r&0xff00ff00)>>1; \
+         y2=r&0xff0000; \
+         *dst++=y|y2|((uv1+uv2)&0xff00ff00);\
+      } \
+   }
+#else /* ppc etc */
+#define COPY_LINE2(SRC, END, DST) \
+   {\
+      SRC_PIXEL  *src = SRC; \
+      SRC_PIXEL  *end = END; \
+      unsigned long *dst = (unsigned long *)DST; \
+      unsigned int r,y,y2,uv1,uv2; \
+      for(;src<end;) \
+      { \
+         r=INDIRECT[*src++]; \
+         y=r&0xff000000 ; \
+         uv1=(r&0x00ff00ff); \
+         r=INDIRECT[*src++]; \
+         uv2=(uv1+(r&0x00ff00ff))>>1; \
+         y2=r&0xff00; \
+         *dst++=y|y2|(uv2&0x00ff00ff); \
       } \
    }
+#endif
 #else /* normal indirect */
 #define COPY_LINE2(SRC, END, DST) \
    SRC_PIXEL  *src = SRC; \
-----------------------------------------------------------------------

I have added the patch to the ebuild for all big-endian archs. Please test this
on sparc, mips and alpha.

Great work, I always assumed this was a bug in the ati driver. ;)
BTW, have you submitted the patch to the xmame developers? I assume 0.79 will
be released shortly.

Yes. I did sent the patch to the xmame list. It already is in 0.79 beta
source tree so in the next release it should be in public sources.

As there is already xmame-0.80.1 out and all arches made it stable, I close
this bug.

Somehow I forgot to close.