--- hatari/src/convert/vdi2.c	2019/04/01 07:10:25	1.1.1.2
+++ hatari/src/convert/vdi2.c	2019/04/09 08:49:45	1.1.1.7
@@ -1,87 +1,70 @@
-/* Screen Conversion, VDI Res to 2Colour (1-Bit and 8-Bit) */
+/*
+  Hatari - vdi2.c
 
-#if 0  /* Currently unused */
-void ConvertVDIRes_2Colour_1Bit(void)
-{
-  /* Copy palette to bitmap (2 colours) */
-
-  if (HBLPalettes[0]==0x777) {
-    ScreenBMP.Colours[0].rgbRed = ScreenBMP.Colours[0].rgbGreen = ScreenBMP.Colours[0].rgbBlue = 0xff;
-    ScreenBMP.Colours[1].rgbRed = ScreenBMP.Colours[1].rgbGreen = ScreenBMP.Colours[1].rgbBlue = 0x00;
-  }
-  else {
-    ScreenBMP.Colours[0].rgbRed = ScreenBMP.Colours[0].rgbGreen = ScreenBMP.Colours[0].rgbBlue = 0x00;
-    ScreenBMP.Colours[1].rgbRed = ScreenBMP.Colours[1].rgbGreen = ScreenBMP.Colours[1].rgbBlue = 0xff;
-  }
+  This file is distributed under the GNU Public License, version 2 or at your
+  option any later version. Read the file gpl.txt for details.
 
-  /* Simply copy ST screen, as same format! */
-  memcpy(pPCScreenDest,pSTScreen,(VDIWidth/8)*VDIHeight);
+  Screen Conversion, monochrome VDI resolution
+*/
 
-  bScreenContentsChanged = TRUE;
-}
-#endif
 
-
-void ConvertVDIRes_2Colour(void)
+static void ConvertVDIRes_2Colour(void)
 {
-  Uint16 *edi, *ebp;
-  Uint32 *esi;
-  register Uint16 eax, ebx;
-
-  ScrY = 0;                             /* Starting line in ST screen */
-
-  edi = (Uint16 *)pSTScreen;            /* ST format screen */
-  ebp = (Uint16 *)pSTScreenCopy;        /* Previous ST format screen */
-
-  do      /* y-loop */
-  {
-    esi = (Uint32 *)pPCScreenDest;      /* PC format screen, byte per pixel 256 colours */
-
-    ScrX = VDIWidth >> 4;               /* Amount to draw across in 16-pixels (4 bytes) */
-
-    do          /* x-loop */
-    {
-      /* Do 16 pixels at one time */
-      ebx = *edi;
-
-      if( (ScrUpdateFlag&0xe0000000) || ebx!=*ebp )  /* Does differ? */
-      {
-        bScreenContentsChanged = TRUE;
+	Uint16 *edi, *ebp;
+	Uint32 *esi;
+	Uint16 eax, ebx;
+	int y, x, update;
+
+	edi = (Uint16 *)pSTScreen;            /* ST format screen */
+	ebp = (Uint16 *)pSTScreenCopy;        /* Previous ST format screen */
+	update = ScrUpdateFlag & PALETTEMASK_UPDATEMASK;
+
+	for (y = 0; y < VDIHeight; y++)
+	{
+
+		esi = (Uint32 *)pPCScreenDest;  /* PC format screen, byte per pixel 256 colors */
+
+		x = VDIWidth >> 4;              /* Amount to draw across in 16-pixels (4 bytes) */
+
+		do  /* x-loop */
+		{
+			/* Do 16 pixels at one time */
+			ebx = *edi;
+
+			if (update || ebx != *ebp)  /* Does differ? */
+			{
+				bScreenContentsChanged = true;
 
 #if SDL_BYTEORDER == SDL_BIG_ENDIAN
-        /* Plot in 'right-order' on big endian systems */
-        HIGH_BUILD_PIXELS_0 ;           /* Generate pixels [4,5,6,7] */
-        PLOT_HIGH_640_8BIT(3) ;
-        HIGH_BUILD_PIXELS_1 ;           /* Generate pixels [0,1,2,3] */
-        PLOT_HIGH_640_8BIT(2) ;
-        HIGH_BUILD_PIXELS_2 ;           /* Generate pixels [12,13,14,15] */
-        PLOT_HIGH_640_8BIT(1) ;
-        HIGH_BUILD_PIXELS_3 ;           /* Generate pixels [8,9,10,11] */
-        PLOT_HIGH_640_8BIT(0) ;
+				/* Plot in 'right-order' on big endian systems */
+				HIGH_BUILD_PIXELS_0 ;   /* Generate pixels [12,13,14,15] */
+				PLOT_HIGH_640_8BIT(3) ;
+				HIGH_BUILD_PIXELS_1 ;   /* Generate pixels [8,9,10,11] */
+				PLOT_HIGH_640_8BIT(2) ;
+				HIGH_BUILD_PIXELS_2 ;   /* Generate pixels [4,5,6,7] */
+				PLOT_HIGH_640_8BIT(1) ;
+				HIGH_BUILD_PIXELS_3 ;   /* Generate pixels [0,1,2,3] */
+				PLOT_HIGH_640_8BIT(0) ;
 #else
-        /* Plot in 'wrong-order', as ebx is 68000 endian */
-        HIGH_BUILD_PIXELS_0 ;           /* Generate pixels [4,5,6,7] */
-        PLOT_HIGH_640_8BIT(1) ;
-        HIGH_BUILD_PIXELS_1 ;           /* Generate pixels [0,1,2,3] */
-        PLOT_HIGH_640_8BIT(0) ;
-        HIGH_BUILD_PIXELS_2 ;           /* Generate pixels [12,13,14,15] */
-        PLOT_HIGH_640_8BIT(3) ;
-        HIGH_BUILD_PIXELS_3 ;           /* Generate pixels [8,9,10,11] */
-        PLOT_HIGH_640_8BIT(2) ;
+				/* Plot in 'wrong-order', as ebx is 68000 endian */
+				HIGH_BUILD_PIXELS_0 ;   /* Generate pixels [4,5,6,7] */
+				PLOT_HIGH_640_8BIT(1) ;
+				HIGH_BUILD_PIXELS_1 ;   /* Generate pixels [0,1,2,3] */
+				PLOT_HIGH_640_8BIT(0) ;
+				HIGH_BUILD_PIXELS_2 ;   /* Generate pixels [12,13,14,15] */
+				PLOT_HIGH_640_8BIT(3) ;
+				HIGH_BUILD_PIXELS_3 ;   /* Generate pixels [8,9,10,11] */
+				PLOT_HIGH_640_8BIT(2) ;
 #endif
-      }
-
-      esi += 4;                         /* Next PC pixels */
-      edi += 1;                         /* Next ST pixels */
-      ebp += 1;                         /* Next ST copy pixels */
-    }
-    while( --ScrX );                    /* Loop on X */
-
-    pPCScreenDest = (void *)(((Uint8 *)pPCScreenDest)+PCScreenBytesPerLine);  /* Offset to next line */
-
-    ScrY += 1;
-  }
-  while( ScrY < VDIHeight );            /* Loop on Y */
+			}
 
+			esi += 4;                   /* Next PC pixels */
+			edi += 1;                   /* Next ST pixels */
+			ebp += 1;                   /* Next ST copy pixels */
+		}
+		while (--x);                    /* Loop on X */
+
+		/* Offset to next line */
+		pPCScreenDest = (((Uint8 *)pPCScreenDest) + PCScreenBytesPerLine);
+	}
 }
-