--- hatari/src/convert/vdi16.c	2019/04/01 07:09:16	1.1
+++ hatari/src/convert/vdi16.c	2019/04/01 07:12:50	1.1.1.3
@@ -1,109 +1,69 @@
-// Screen Conversion, VDI Res to 16Colour
+/* Screen Conversion, VDI Res to 16Colour */
 
-void ConvertVDIRes_16Colour_YLoop(void);
-void Line_ConvertVDIRes_16Colour(void);
-
-void ConvertVDIRes_16Colour(void)
-{
-fprintf(stderr,"FIXME: Screen Conversion, VDI Res to 16Colour\n");
-/* FIXME */
-/*
-  __asm {
-    push  ebp
-    push  edi
-    push  esi
-    push  ebx
-
-    xor    edx,edx                  // Clear index for loop
-
-    mov    eax,0
-    mov    [ScrY],eax                // Starting line in ST screen
-
-    // Get screen addresses, 'edi'-ST screen, 'ebp'-Previous ST screen, 'esi'-PC screen
-    mov    edi,[pSTScreen]              // ST format screen 4-plane 16 colours
-    mov    ebp,[pSTScreenCopy]            // Previous ST format screen
-    mov    esi,[pPCScreenDest]            // PC format screen, byte per pixel 256 colours
-
-    jmp    ConvertVDIRes_16Colour_YLoop
-  }
-*/
-}
-/*
-NAKED void ConvertVDIRes_16Colour_YLoop(void)
+static void ConvertVDIRes_16Colour(void)
 {
-  __asm {
-    // Get screen addresses, 'edi'-ST screen, 'ebp'-Previous ST screen, 'esi'-PC screen
-    mov    esi,[pPCScreenDest]            // PC format screen, byte per pixel 256 colours
+  Uint32 *edi, *ebp;
+  Uint32 *esi;
+  Uint32 eax, edx;
+  Uint32 ebx, ecx;
+  int y, x;
+
+  edx = eax = 0;
+
+  /* Get screen addresses, 'edi'-ST screen, 'ebp'-Previous ST screen,
+   * 'esi'-PC screen */
+  
+  edi = (Uint32 *)pSTScreen;        /* ST format screen 4-plane 16 colours */
+  ebp = (Uint32 *)pSTScreenCopy;    /* Previous ST format screen */
+
+  for (y = 0; y < VDIHeight; y++) {
+
+    esi = (Uint32 *)pPCScreenDest;   /* PC format screen, byte per pixel 256 colours */
+
+    x = VDIWidth >> 4;           /* Amount to draw across - in 16-pixels (8 bytes) */
+
+    do          /* x-loop */
+    {
+      /* Do 16 pixels at one time */
+      ebx = *edi;
+      ecx = *(edi+1);
+
+      /* Full update? or just test changes? */
+      if((ScrUpdateFlag&0xe0000000) || ebx!=*ebp || ecx!=*(ebp+1))  /* Does differ? */
+      {
+        bScreenContentsChanged = TRUE;
+
+#if SDL_BYTEORDER == SDL_BIG_ENDIAN
+        /* Plot pixels */
+        LOW_BUILD_PIXELS_0 ;      /* Generate 'ecx' as pixels [4,5,6,7] */
+        PLOT_LOW_320_8BIT(3) ;
+        LOW_BUILD_PIXELS_1 ;      /* Generate 'ecx' as pixels [12,13,14,15] */
+        PLOT_LOW_320_8BIT(1) ;
+        LOW_BUILD_PIXELS_2 ;      /* Generate 'ecx' as pixels [0,1,2,3] */
+        PLOT_LOW_320_8BIT(2) ;
+        LOW_BUILD_PIXELS_3 ;      /* Generate 'ecx' as pixels [8,9,10,11] */
+        PLOT_LOW_320_8BIT(0) ;
+#else
+        /* Plot pixels */
+        LOW_BUILD_PIXELS_0 ;      /* Generate 'ecx' as pixels [4,5,6,7] */
+        PLOT_LOW_320_8BIT(1) ;
+        LOW_BUILD_PIXELS_1 ;      /* Generate 'ecx' as pixels [12,13,14,15] */
+        PLOT_LOW_320_8BIT(3) ;
+        LOW_BUILD_PIXELS_2 ;      /* Generate 'ecx' as pixels [0,1,2,3] */
+        PLOT_LOW_320_8BIT(0) ;
+        LOW_BUILD_PIXELS_3 ;      /* Generate 'ecx' as pixels [8,9,10,11] */
+        PLOT_LOW_320_8BIT(2) ;
+#endif
+      }
+
+      esi += 4;                         /* Next PC pixels */
+      edi += 2;                         /* Next ST pixels */
+      ebp += 2;                         /* Next ST copy pixels */
+    }
+    while( --x );                    /* Loop on X */
 
-    jmp    Line_ConvertVDIRes_16Colour
+    /* Offset to next line */
+    pPCScreenDest = (void *)(((Uint8 *)pPCScreenDest)+PCScreenBytesPerLine);
   }
 }
-NAKED void Line_ConvertVDIRes_16Colour(void)
-{
-  __asm {
-    mov    eax,[VDIWidth]              // Amount to draw across
-    shr    eax,4                  // in 16-pixels(8 bytes)
-    mov    [ScrX],eax
-x_loop:
-#ifdef TEST_SCREEN_UPDATE
-    mov    WORD PTR [esi+0],0
-    mov    WORD PTR [esi+4],0
-    mov    WORD PTR [esi+8],0
-    mov    WORD PTR [esi+12],0
-    mov    WORD PTR [esi+16],0
-    mov    WORD PTR [esi+20],0
-    mov    WORD PTR [esi+24],0
-    mov    WORD PTR [esi+28],0
-#endif  //TEST_SCREEN_UPDATE
-
-    // Do 16 pixels at one time
-    mov    ebx,[edi]
-    mov    ecx,4[edi]
-    // Full update? or just test changes?
-    test  [ScrUpdateFlag],0xe0000000
-    jne    copy_word                // Force
-    // Does differ?
-    cmp    ebx,[ebp]
-    jne    copy_word
-    cmp    ecx,4[ebp]
-    je    next_word                // Pixels are same as last frame, so ignore
-
-copy_word:
-    mov    [bScreenContentsChanged],TRUE
-
-    // Plot pixels
-    LOW_BUILD_PIXELS_0                // Generate 'ecx' as pixels [4,5,6,7]
-    PLOT_LOW_320_8BIT(4)
-    LOW_BUILD_PIXELS_1                // Generate 'ecx' as pixels [12,13,14,15]
-    PLOT_LOW_320_8BIT(12)
-    LOW_BUILD_PIXELS_2                // Generate 'ecx' as pixels [0,1,2,3]
-    PLOT_LOW_320_8BIT(0)
-    LOW_BUILD_PIXELS_3                // Generate 'ecx' as pixels [8,9,10,11]
-    PLOT_LOW_320_8BIT(8)
-
-next_word:
-    add    esi,16                  // Next PC pixels
-    add    edi,8                  // Next ST pixels
-    add    ebp,8                  // Next ST copy pixels
-
-    dec    [ScrX]
-    jne    x_loop                  // Loop on X
-
-    mov    eax,[pPCScreenDest]
-    add    eax,[PCScreenBytesPerLine]        // Offset to next line
-    mov    [pPCScreenDest],eax
-    
-    inc    [ScrY]
-    mov    eax,[VDIHeight]
-    cmp    [ScrY],eax
-    jne    ConvertVDIRes_16Colour_YLoop    // And on Y
-
-    pop    ebx
-    pop    esi
-    pop    edi
-    pop    ebp
 
-    ret
-  }
-}
-*/