From 4e4e6031891d7db27845578d174cec995afce976 Mon Sep 17 00:00:00 2001
From: Royce Mitchell III <royce3@ev1.net>
Date: Mon, 11 Aug 2003 03:51:44 +0000
Subject: [PATCH] fixed several bugs, simplified some calculations. This
 appears to have broken framerect drawing ( zoomin on min/max buttons ), but I
 think that was expecting the wrong behavior.

svn path=/trunk/; revision=5519
---
 .../drivers/dd/vga/display/objects/paint.c    | 52 ++++++++-------
 .../dd/vga/display/vgavideo/vgavideo.c        | 63 +++++++------------
 .../dd/vga/display/vgavideo/vgavideo.h        |  3 +
 3 files changed, 57 insertions(+), 61 deletions(-)

diff --git a/reactos/drivers/dd/vga/display/objects/paint.c b/reactos/drivers/dd/vga/display/objects/paint.c
index f50ab17402e..2011c9c7aed 100644
--- a/reactos/drivers/dd/vga/display/objects/paint.c
+++ b/reactos/drivers/dd/vga/display/objects/paint.c
@@ -17,17 +17,23 @@ BOOL VGADDIFillSolid(SURFOBJ *Surface, RECTL Dimensions, ULONG iColor)
   DPRINT("VGADDIFillSolid: x:%d, y:%d, w:%d, h:%d\n", x, y, w, h);
 
   // Swap dimensions so that x, y are at topmost left
-  if(Dimensions.right < Dimensions.left) {
+  if ( Dimensions.right < Dimensions.left )
+  {
     x  = Dimensions.right;
     x2 = Dimensions.left;
-  } else {
+  }
+  else
+  {
     x2 = Dimensions.right;
     x  = Dimensions.left;
   }
-  if(Dimensions.bottom < Dimensions.top) {
+  if ( Dimensions.bottom < Dimensions.top )
+  {
     y  = Dimensions.bottom;
     y2 = Dimensions.top;
-  } else {
+  }
+  else
+  {
     y2 = Dimensions.bottom;
     y  = Dimensions.top;
   }
@@ -40,75 +46,77 @@ BOOL VGADDIFillSolid(SURFOBJ *Surface, RECTL Dimensions, ULONG iColor)
   offset = xconv[x]+y80[y];
 
   // Make a note of original x
-  orgx=x;
+  orgx = x;
 
   // If width is less than 8, draw using vertical lines
-  if(w<8)
+  if ( w < 8 )
   {
     for (i=x; i<x+w; i++)
       vgaVLine(i, y, h, iColor);
 
   // Otherwise, use the optimized code
-  } else {
+  }
+  else
+  {
 
     // Calculate the left mask pixels, middle bytes and right mask pixel
-    leftpix = 8-mod(x, 8);
-    rightpix = mod(x+w, 8);
+    ileftpix = 7 - mod8(x-1);
+    rightpix = mod8(x+w);
     midpix = (w-leftpix-rightpix) / 8;
 
     ileftpix = leftpix;
     irightpix = rightpix;
     imidpix = midpix;
 
-    pre1=xconv[x-(8-ileftpix)]+y80[y];
+    pre1 = xconv[(x-1)&~7] + y80[y];
     orgpre1=pre1;
 
-    if(ileftpix>0)
+    if ( ileftpix > 0 )
     {
       // Write left pixels
       WRITE_PORT_UCHAR((PUCHAR)0x3ce,0x08);     // set the mask
       WRITE_PORT_UCHAR((PUCHAR)0x3cf,startmasks[ileftpix]);
 
       tmppre1 = pre1;
-      for (j=y; j<y+h; j++)
+      for ( j = y; j < y+h; j++ )
       {
         a = READ_REGISTER_UCHAR(vidmem + tmppre1);
         WRITE_REGISTER_UCHAR(vidmem + tmppre1, iColor);
-        tmppre1+=80;
+        tmppre1 += 80;
       }
 
       // Prepare new x for the middle
-      x=orgx+8;
+      x = orgx + 8;
     }
 
-    if(imidpix>0)
+    if ( imidpix > 0 )
     {
-      midpre1=xconv[x]+y80[y];
+      midpre1=xconv[x] + y80[y];
 
       // Set mask to all pixels in byte
       WRITE_PORT_UCHAR((PUCHAR)0x3ce, 0x08);
 
       WRITE_PORT_UCHAR((PUCHAR)0x3cf, 0xff);
 
-      for (j=y; j<y+h; j++)
+      for ( j = y; j < y+h; j++ )
       {
         memset(vidmem+midpre1, iColor, imidpix); // write middle pixels, no need to read in latch because of the width
-        midpre1+=80;
+        midpre1 += 80;
       }
     }
 
-    x=orgx+w-irightpix;
-    pre1=xconv[x]+y80[y];
+    x = orgx + w - irightpix;
+    pre1 = xconv[x] + y80[y];
 
     // Write right pixels
     WRITE_PORT_UCHAR((PUCHAR)0x3ce,0x08);     // set the mask bits
     WRITE_PORT_UCHAR((PUCHAR)0x3cf,endmasks[irightpix]);
 
-    for (j=y; j<y+h; j++)
+    for ( j = y; j < y+h; j++ )
     {
       a = READ_REGISTER_UCHAR(vidmem + pre1);
       WRITE_REGISTER_UCHAR(vidmem + pre1, iColor);
-      pre1+=80;
+      pre1 += 80;
     }
   }
 
diff --git a/reactos/drivers/dd/vga/display/vgavideo/vgavideo.c b/reactos/drivers/dd/vga/display/vgavideo/vgavideo.c
index 576c746e14d..0c5f499ea5e 100644
--- a/reactos/drivers/dd/vga/display/vgavideo/vgavideo.c
+++ b/reactos/drivers/dd/vga/display/vgavideo/vgavideo.c
@@ -58,11 +58,11 @@ div_t div(int num, int denom)
   return r;
 }
 
-int mod(int num, int denom)
+/*int mod(int num, int denom)
 {
   div_t dvt = div(num, denom);
   return dvt.rem;
-}
+}*/
 
 BYTE bytesPerPixel(ULONG Format)
 {
@@ -109,17 +109,15 @@ VOID vgaPreCalc()
   startmasks[5] = 31;
   startmasks[6] = 63;
   startmasks[7] = 127;
-  startmasks[8] = 255;
 
-  endmasks[0] = 128;
-  endmasks[1] = 192;
-  endmasks[2] = 224;
-  endmasks[3] = 240;
-  endmasks[4] = 248;
-  endmasks[5] = 252;
-  endmasks[6] = 254;
-  endmasks[7] = 255;
-  endmasks[8] = 255;
+  endmasks[0] = 0;
+  endmasks[1] = 128;
+  endmasks[2] = 192;
+  endmasks[3] = 224;
+  endmasks[4] = 240;
+  endmasks[5] = 248;
+  endmasks[6] = 252;
+  endmasks[7] = 254;
 
   for(j=0; j<80; j++)
   {
@@ -283,25 +281,19 @@ BOOL vgaHLine(INT x, INT y, INT len, UCHAR c)
     for (i=x; i<x+len; i++)
       vgaPutPixel(i, y, c);
 
-   return TRUE;
+    return TRUE;
   }
 
   // Calculate the left mask pixels, middle bytes and right mask pixel
-  ileftpix = 8-mod(x, 8);
-  irightpix = mod(x+len, 8);
+  ileftpix = 7 - mod8(x-1);
+  irightpix = mod8(x+len);
   imidpix = (len-ileftpix-irightpix) / 8;
 
-  if(ileftpix == 8)
-  {
-    ileftpix = 0;
-    imidpix++;
-  }
-
-  pre1=xconv[x-(8-ileftpix)]+y80[y];
+  pre1 = xconv[(x-1)&~7] + y80[y];
   orgpre1=pre1;
 
   // Left
-  if(ileftpix>0)
+  if ( ileftpix > 0 )
   {
     // Write left pixels
     WRITE_PORT_UCHAR((PUCHAR)GRA_I,0x08);     // set the mask
@@ -311,12 +303,12 @@ BOOL vgaHLine(INT x, INT y, INT len, UCHAR c)
     WRITE_REGISTER_UCHAR(vidmem + pre1, c);
 
     // Prepare new x for the middle
-    x=orgx+8;
+    x = orgx + 8;
   }
 
-  if(imidpix>0)
+  if ( imidpix > 0 )
   {
-    midpre1=xconv[x]+y80[y];
+    midpre1 = xconv[x] + y80[y];
 
     // Set mask to all pixels in byte
     WRITE_PORT_UCHAR((PUCHAR)GRA_I, 0x08);
@@ -326,21 +318,14 @@ BOOL vgaHLine(INT x, INT y, INT len, UCHAR c)
 
   if ( irightpix > 0 )
   {
-    x=orgx+len-irightpix;
-#if 0
-    for(i=x; i<x+irightpix; i++)
-    {
-      vgaPutPixel(i, y, c);
-    }
-#else
-    pre1=xconv[x]+y80[y];
+    x = orgx + len - irightpix;
+    pre1 = xconv[x] + y80[y];
 
     // Write right pixels
     WRITE_PORT_UCHAR((PUCHAR)GRA_I,0x08);     // set the mask bits
     WRITE_PORT_UCHAR((PUCHAR)GRA_D, endmasks[irightpix]);
     a = READ_REGISTER_UCHAR(vidmem + pre1);
     WRITE_REGISTER_UCHAR(vidmem + pre1, c);
-#endif
   }
 
   return TRUE;
@@ -499,7 +484,7 @@ void DIB_BltFromVGA(int x, int y, int w, int h, void *b, int Dest_lDelta)
   BYTE  b1, b2;
 
   // Check if the width is odd
-  if(mod(w, 2)>0)
+  if(mod2(w)>0)
   {
     edgePixel = TRUE;
     x2 -= 1;
@@ -587,7 +572,7 @@ void DIB_TransparentBltToVGA(int x, int y, int w, int h, void *b, int Source_lDe
   BYTE  b1, b2;
 
   // Check if the width is odd
-  if(mod(w, 2)>0)
+  if(mod2(w)>0)
   {
     edgePixel = TRUE;
     x2 -= 1;
@@ -949,7 +934,7 @@ void DFB_BltToDIB(int x, int y, int w, int h, void *b, int bw, void *bdib, int d
   for (i=w; i>0; i--) {
 
     // determine the bit shift for the DIB pixel
-    dib_shift = mod(w-i, 2);
+    dib_shift = mod2(w-i);
     if(dib_shift > 0) dib_shift = 4;
     dibTmp = dib;
 
@@ -978,7 +963,7 @@ void DIB_BltToDFB(int x, int y, int w, int h, void *b, int bw, void *bdib, int d
   for (i=w; i>0; i--) {
 
     // determine the bit shift for the DIB pixel
-    dib_shift = mod(w-i, 2);
+    dib_shift = mod2(w-i);
     if(dib_shift > 0) {
       dib_shift = 0;
       dib_and = 0x0f;
diff --git a/reactos/drivers/dd/vga/display/vgavideo/vgavideo.h b/reactos/drivers/dd/vga/display/vgavideo/vgavideo.h
index 1bfbc4bfd01..77be5ab1457 100644
--- a/reactos/drivers/dd/vga/display/vgavideo/vgavideo.h
+++ b/reactos/drivers/dd/vga/display/vgavideo/vgavideo.h
@@ -66,3 +66,6 @@ BOOL VGADDIIntersectRect(PRECTL prcDst, PRECTL prcSrc1, PRECTL prcSrc2);
 #define ASSIGNMK4(x, y, mask) mask = 0x80 >> ((x) & 7);
 
 void get_masks(int x, int w);
+
+#define mod8(n) ((n)&7)
+#define mod2(n) ((n)&1)