--- hatari/src/convert/spec320x16.c	2019/04/01 07:09:49	1.1.1.3
+++ hatari/src/convert/spec320x16.c	2019/04/01 07:12:49	1.1.1.5
@@ -1,82 +1,112 @@
 /* Screen Conversion, Spec512 to 320x16Bit */
 
-void ConvertSpec512_320x16Bit(void)
+static void ConvertSpec512_320x16Bit(void)
 {
  Uint32 *edi, *ebp;
  Uint16 *esi;
- register Uint32 eax, ebx, ecx, edx;
+ Uint32 eax, ebx, ecx, edx;
+ Uint32 pixelspace[4]; /* Workspace to store pixels to so can print in right order for Spec512 */
+ int y, x;
 
  Spec512_StartFrame();            /* Start frame, track palettes */
 
  edx = 0;                         /* Clear index for loop */
 
- ScrY = STScreenStartHorizLine;   /* Starting line in ST screen */
-
- do      /* y-loop */
-  {
+ for (y = STScreenStartHorizLine; y < STScreenEndHorizLine; y++) {
 
    Spec512_StartScanLine();         /* Build up palettes for every 4 pixels, store in 'ScanLinePalettes' */
    edx = 0;                         /* Clear index for loop */
 
    /* Get screen addresses, 'edi'-ST screen, 'ebp'-Previous ST screen, 'esi'-PC screen */
-   eax = STScreenLineOffset[ScrY] + STScreenLeftSkipBytes;  /* Offset for this line + Amount to skip on left hand side */
+   eax = STScreenLineOffset[y] + STScreenLeftSkipBytes;  /* Offset for this line + Amount to skip on left hand side */
    edi = (Uint32 *)((Uint8 *)pSTScreen + eax);        /* ST format screen 4-plane 16 colours */
    ebp = (Uint32 *)((Uint8 *)pSTScreenCopy + eax);    /* Previous ST format screen */
    esi = (Uint16 *)pPCScreenDest;                     /* PC format screen */
 
-   ScrX=STScreenWidthBytes>>3;   /* Amount to draw across in 16-pixels (8 bytes) */
+   x = STScreenWidthBytes>>3;   /* Amount to draw across in 16-pixels (8 bytes) */
 
    do    /* x-loop */
     {
      ebx = *edi;                /* Do 16 pixels at one time */
      ecx = *(edi+1);
 
+#if SDL_BYTEORDER == SDL_LIL_ENDIAN
+
      /* Convert planes to byte indices - as works in wrong order store to workspace so can read back in order! */
      LOW_BUILD_PIXELS_0 ;               /* Generate 'ecx' as pixels [4,5,6,7] */
-     PixelWorkspace[1] = ecx;
+     pixelspace[1] = ecx;
      LOW_BUILD_PIXELS_1 ;               /* Generate 'ecx' as pixels [12,13,14,15] */
-     PixelWorkspace[3] = ecx;
+     pixelspace[3] = ecx;
      LOW_BUILD_PIXELS_2 ;               /* Generate 'ecx' as pixels [0,1,2,3] */
-     PixelWorkspace[0] = ecx;
+     pixelspace[0] = ecx;
      LOW_BUILD_PIXELS_3 ;               /* Generate 'ecx' as pixels [8,9,10,11] */
-     PixelWorkspace[2] = ecx;
+     pixelspace[2] = ecx;
 
      /* And plot, the Spec512 is offset by 1 pixel and works on 'chunks' of 4 pixels */
      /* So, we plot 1_4_4_3 to give 16 pixels, changing palette between */
      /* (last one is used for first of next 16-pixels) */
-     ecx = PixelWorkspace[0];
+     ecx = pixelspace[0];
      PLOT_SPEC512_LEFT_LOW_320_16BIT(0) ;
      Spec512_UpdatePaletteSpan();
 
-     ecx = *(Uint32 *)( ((Uint8 *)PixelWorkspace)+1 );  /* FIXME: I guess this will not work on some non-Intel architectures - Thothy */
+     ecx = *(Uint32 *)( ((Uint8 *)pixelspace)+1 );
      PLOT_SPEC512_MID_320_16BIT(1) ;
      Spec512_UpdatePaletteSpan();
 
-     ecx = *(Uint32 *)( ((Uint8 *)PixelWorkspace)+5 );
+     ecx = *(Uint32 *)( ((Uint8 *)pixelspace)+5 );
      PLOT_SPEC512_MID_320_16BIT(5) ;
      Spec512_UpdatePaletteSpan();
 
-     ecx = *(Uint32 *)( ((Uint8 *)PixelWorkspace)+9 );
+     ecx = *(Uint32 *)( ((Uint8 *)pixelspace)+9 );
      PLOT_SPEC512_MID_320_16BIT(9) ;
      Spec512_UpdatePaletteSpan();
 
-     ecx = *(Uint32 *)( ((Uint8 *)PixelWorkspace)+13 );
+     ecx = *(Uint32 *)( ((Uint8 *)pixelspace)+13 );
      PLOT_SPEC512_END_LOW_320_16BIT(13) ;
 
+#else
+     /* Well, I didn't get the code above working on big-endian  machines, too,
+        But I hope the following lines are good enough to also do the job... - THH */
+
+     LOW_BUILD_PIXELS_0 ;
+     pixelspace[3] = ecx;
+     LOW_BUILD_PIXELS_1 ;
+     pixelspace[1] = ecx;
+     LOW_BUILD_PIXELS_2 ;
+     pixelspace[2] = ecx;
+     LOW_BUILD_PIXELS_3 ;
+     pixelspace[0] = ecx;
+
+     ecx = pixelspace[0];
+     PLOT_SPEC512_MID_320_16BIT(0) ;
+     Spec512_UpdatePaletteSpan();
+
+     ecx = pixelspace[1];
+     PLOT_SPEC512_MID_320_16BIT(4) ;
+     Spec512_UpdatePaletteSpan();
+
+     ecx = pixelspace[2];
+     PLOT_SPEC512_MID_320_16BIT(8) ;
+     Spec512_UpdatePaletteSpan();
+
+     ecx = pixelspace[3];
+     PLOT_SPEC512_MID_320_16BIT(12) ;
+     Spec512_UpdatePaletteSpan();
+
+#endif
+
      esi += 16;                             /* Next PC pixels */
      edi += 2;                              /* Next ST pixels */
      ebp += 2;                              /* Next ST copy pixels */
     }
-   while( --ScrX );                         /* Loop on X */
+   while( --x );                         /* Loop on X */
 
    Spec512_EndScanLine();
 
-   pPCScreenDest = (void *)(((unsigned char *)pPCScreenDest)+PCScreenBytesPerLine);  /* Offset to next line */
-   ScrY += 1;
+   /* Offset to next line */
+   pPCScreenDest = (void *)(((unsigned char *)pPCScreenDest)+PCScreenBytesPerLine);
   }
- while( ScrY < STScreenEndHorizLine );      /* Loop on Y */
 
  bScreenContentsChanged = TRUE;
-
 }