diff --git a/src/brush.c b/src/brush.c
index b69338ca..a2ace38f 100644
--- a/src/brush.c
+++ b/src/brush.c
@@ -1266,18 +1266,18 @@ void Capture_brush_with_lasso(int vertices, short * points,short clear)
     Pixel_figure=Pixel_figure_in_brush;
 
     memset(Brush,Back_color,(long)Brush_width*Brush_height);
-    Polyfill_general(vertices,points,~Back_color);
+    Polyfill_general(vertices,points,xor_lut[Back_color]);
 
     // On retrace les bordures du lasso:
     for (temp=1; temp<vertices; temp++)
     {
       Draw_line_general(points[(temp-1)<<1],points[((temp-1)<<1)+1],
                            points[temp<<1],points[(temp<<1)+1],
-                           ~Back_color);
+                           xor_lut[Back_color]);
     }
     Draw_line_general(points[(vertices-1)<<1],points[((vertices-1)<<1)+1],
                          points[0],points[1],
-                         ~Back_color);
+                         xor_lut[Back_color]);
 
     // On scanne la brosse pour remplacer tous les pixels affectés par le
     // polyfill par ceux de l'image:
diff --git a/src/brush_ops.c b/src/brush_ops.c
index 7b1e75e1..7c91b9f5 100644
--- a/src/brush_ops.c
+++ b/src/brush_ops.c
@@ -1156,7 +1156,7 @@ void Draw_stretch_spot(short x_pos, short y_pos)
     if (y>=Limit_top && y<=Limit_visible_bottom)
       for (x=x_pos-1;x<x_pos+1;x++)
         if (x>=Limit_left && x<=Limit_visible_right)
-          Pixel_preview(x,y,~Read_pixel(x-Main_offset_X,y-Main_offset_Y));
+          Pixel_preview(x,y,xor_lut[Read_pixel(x-Main_offset_X,y-Main_offset_Y)]);
   Update_part_of_screen(x_pos-1, y_pos-1, 2, 2);
 }
 
diff --git a/src/buttons.c b/src/buttons.c
index 78780a4b..f9755195 100644
--- a/src/buttons.c
+++ b/src/buttons.c
@@ -956,10 +956,10 @@ void Button_Settings(void)
   {"Coordinates:",1,&(selected_config.Coords_rel),0,1,0,Lookup_Coords},
   {"Separate colors:",1,&(selected_config.Separate_colors),0,1,0,Lookup_YesNo},
   {"Safety colors:",1,&(selected_config.Safety_colors),0,1,0,Lookup_YesNo},
-  {"Grid XOR color:",1,&(selected_config.Grid_XOR_color),0,255,3,NULL},
   {"Sync views:",1,&(selected_config.Sync_views),0,1,0,Lookup_YesNo},
   {"",0,NULL,0,0,0,NULL},
   {"",0,NULL,0,0,0,NULL},
+  {"",0,NULL,0,0,0,NULL},
   
   {"           --- Input  ---",0,NULL,0,0,0,NULL},
   {"Scrollbar speed",0,NULL,0,0,0,NULL},
diff --git a/src/global.h b/src/global.h
index 276bc503..a3beff6b 100644
--- a/src/global.h
+++ b/src/global.h
@@ -334,6 +334,8 @@ GFX2_GLOBAL long Main_edits_since_safety_backup;
 GFX2_GLOBAL Uint32 Main_time_of_safety_backup;
 /// Letter prefix for the filenames of safety backups. a or b
 GFX2_GLOBAL byte Main_safety_backup_prefix;
+/// Lookup table for XOR effects, pointing each color to the most different one
+GFX2_GLOBAL byte xor_lut[256];
 
 // -- Spare page data
 
diff --git a/src/graph.c b/src/graph.c
index 15e6364f..9001eb84 100644
--- a/src/graph.c
+++ b/src/graph.c
@@ -1100,8 +1100,8 @@ void Fill_general(byte fill_color)
          (x_pos<=Limit_right) &&
          (y_pos>=Limit_top)   &&
          (y_pos<=Limit_bottom) )
-      Pixel_preview(x_pos,y_pos,~Read_pixel(x_pos-Main_offset_X,
-                                           y_pos-Main_offset_Y));
+      Pixel_preview(x_pos,y_pos,xor_lut[Read_pixel(x_pos-Main_offset_X,
+                                           y_pos-Main_offset_Y)]);
   }
   
   // Affichage d'un point pour une preview en xor additif
@@ -1114,7 +1114,7 @@ void Fill_general(byte fill_color)
          (x_pos<=Limit_right) &&
          (y_pos>=Limit_top)   &&
          (y_pos<=Limit_bottom) )
-      Pixel_preview(x_pos,y_pos,~Main_screen[x_pos+y_pos*Main_image_width]);
+      Pixel_preview(x_pos,y_pos,xor_lut[Main_screen[x_pos+y_pos*Main_image_width]]);
   }
   
 
@@ -2884,7 +2884,7 @@ void Horizontal_grid_line(word x_pos,word y_pos,word width)
   int x;
 
   for (x=!(x_pos&1);x<width;x+=2)
-    Pixel(x_pos+x, y_pos, *((y_pos-1)*Pixel_height*VIDEO_LINE_WIDTH+x_pos*Pixel_width+Screen_pixels+x*Pixel_width)^Config.Grid_XOR_color);
+    Pixel(x_pos+x, y_pos, xor_lut[*((y_pos-1)*Pixel_height*VIDEO_LINE_WIDTH+x_pos*Pixel_width+Screen_pixels+x*Pixel_width)]);
 }
 
 void Vertical_grid_line(word x_pos,word y_pos,word height)
@@ -2892,7 +2892,7 @@ void Vertical_grid_line(word x_pos,word y_pos,word height)
   int y;
   
   for (y=!(y_pos&1);y<height;y+=2)
-    Pixel(x_pos, y_pos+y, *(Screen_pixels+(x_pos*Pixel_width-1)+(y_pos*Pixel_height+y*Pixel_height)*VIDEO_LINE_WIDTH)^Config.Grid_XOR_color);
+    Pixel(x_pos, y_pos+y, xor_lut[*(Screen_pixels+(x_pos*Pixel_width-1)+(y_pos*Pixel_height+y*Pixel_height)*VIDEO_LINE_WIDTH)]);
 }
 
 // Tile Grid
diff --git a/src/operatio.c b/src/operatio.c
index 9d9a987a..f986bcff 100644
--- a/src/operatio.c
+++ b/src/operatio.c
@@ -1435,14 +1435,14 @@ void Draw_curve_cross(short x_pos, short y_pos)
     for (i=start_x; i<=end_x; i++)
     {
       temp=x_pos+i-3;
-      Pixel_preview(temp,y_pos,~Read_pixel(temp -Main_offset_X,
-                                          y_pos-Main_offset_Y));
+      Pixel_preview(temp,y_pos,xor_lut[Read_pixel(temp -Main_offset_X,
+                                          y_pos-Main_offset_Y)]);
     }
     for (i=start_y; i<=end_y; i++)
     {
       temp=y_pos+i-3;
-      Pixel_preview(x_pos,temp,~Read_pixel(x_pos-Main_offset_X,
-                                          temp -Main_offset_Y));
+      Pixel_preview(x_pos,temp,xor_lut[Read_pixel(x_pos-Main_offset_X,
+                                          temp -Main_offset_Y)]);
     }
     Update_part_of_screen(x_pos+start_x-3,y_pos+start_y-3,end_x-start_x+1,end_y-start_y+1);
   }
diff --git a/src/palette.c b/src/palette.c
index be09f166..185fca81 100644
--- a/src/palette.c
+++ b/src/palette.c
@@ -3010,66 +3010,3 @@ const T_Components * Favorite_GUI_color(byte color_index)
       return &(Gfx->Default_palette[Gfx->Color[color_index]]);
 }
 
-byte xor_lut[256];
-int Diff(int i, int j) {
-	// TODO try out different difference operators to see if the results get
-	// better (weight the components, use ² instead of abs, use HSL or XYZ or )
-	int diff = 0;
-	diff += abs(Main_palette[i].R - Main_palette[j].R);
-	diff += abs(Main_palette[i].G - Main_palette[j].G);
-	diff += abs(Main_palette[i].B - Main_palette[j].B);
-
-	return diff;
-}
-
-void compute_xor_table()
-{
-	int i;
-	byte found;
-
-	// Initialize the table with some "random" values
-	for(i = 0; i < 256; i++)
-	{
-		xor_lut[i] = 255 - i;
-	}
-
-	do {
-		// Find the smallest difference in the table
-		int mindiff = INT_MAX;
-		int idx;
-		for(i = 0; i < 256; i++)
-		{
-			int diff = Diff(i, xor_lut[i]);
-			if (diff < mindiff) {
-				idx = i;
-				mindiff = diff;
-			}
-		}
-
-		// Try to pair these two colors better
-		found = 0;
-		for(i = 0; i < 256; i++)
-		{
-			// diffs before the swap
-			int before = Diff(idx, xor_lut[idx]) + Diff(i, xor_lut[i]);
-
-			// diffs after the swap
-			int after = Diff(idx, xor_lut[i])  + Diff(i, xor_lut[idx]);
-
-			if (after > before)
-			{
-				// Swapping these colors get us something "more different". Do it !
-				byte idx2 = xor_lut[i];
-				byte i2 = xor_lut[idx];
-
-				xor_lut[i] = i2;
-				xor_lut[i2] = i;
-				xor_lut[idx] = idx2;
-				xor_lut[idx2] = idx;
-
-				found = 1;
-				break;
-			}
-		}
-	} while(found);
-}
diff --git a/src/pxdouble.c b/src/pxdouble.c
index 269ffaea..b3dcdaa9 100644
--- a/src/pxdouble.c
+++ b/src/pxdouble.c
@@ -134,7 +134,7 @@ void Horizontal_XOR_line_double(word x_pos,word y_pos,word width)
   int x;
 
   for (x=0;x<width*ZOOMX;x+=ZOOMX)
-    *(dest+x+VIDEO_LINE_WIDTH+1)=*(dest+x+VIDEO_LINE_WIDTH)=*(dest+x+1)=*(dest+x)=~*(dest+x);
+    *(dest+x+VIDEO_LINE_WIDTH+1)=*(dest+x+VIDEO_LINE_WIDTH)=*(dest+x+1)=*(dest+x)=xor_lut[*(dest+x)];
 }
 
 void Vertical_XOR_line_double(word x_pos,word y_pos,word height)
@@ -143,7 +143,7 @@ void Vertical_XOR_line_double(word x_pos,word y_pos,word height)
   byte *dest=Screen_pixels+x_pos*ZOOMX+y_pos*VIDEO_LINE_WIDTH*ZOOMY;
   for (i=height;i>0;i--)
   {
-    *dest=*(dest+1)=*(dest+VIDEO_LINE_WIDTH)=*(dest+VIDEO_LINE_WIDTH+1)=~*dest;
+    *dest=*(dest+1)=*(dest+VIDEO_LINE_WIDTH)=*(dest+VIDEO_LINE_WIDTH+1)=xor_lut[*dest];
     dest+=VIDEO_LINE_WIDTH*ZOOMY;
   }
 }
diff --git a/src/pxquad.c b/src/pxquad.c
index e9778a51..a74f090d 100644
--- a/src/pxquad.c
+++ b/src/pxquad.c
@@ -149,7 +149,7 @@ void Horizontal_XOR_line_quad(word x_pos,word y_pos,word width)
   int x;
 
   for (x=0;x<width*ZOOMX;x+=ZOOMX)
-    *(dest+x+3*VIDEO_LINE_WIDTH+3)=*(dest+x+3*VIDEO_LINE_WIDTH+2)=*(dest+x+3*VIDEO_LINE_WIDTH+1)=*(dest+x+3*VIDEO_LINE_WIDTH)=*(dest+x+2*VIDEO_LINE_WIDTH+3)=*(dest+x+2*VIDEO_LINE_WIDTH+2)=*(dest+x+2*VIDEO_LINE_WIDTH+1)=*(dest+x+2*VIDEO_LINE_WIDTH)=*(dest+x+VIDEO_LINE_WIDTH+3)=*(dest+x+VIDEO_LINE_WIDTH+2)=*(dest+x+VIDEO_LINE_WIDTH+1)=*(dest+x+VIDEO_LINE_WIDTH)=*(dest+x+3)=*(dest+x+2)=*(dest+x+1)=*(dest+x)=~*(dest+x);
+    *(dest+x+3*VIDEO_LINE_WIDTH+3)=*(dest+x+3*VIDEO_LINE_WIDTH+2)=*(dest+x+3*VIDEO_LINE_WIDTH+1)=*(dest+x+3*VIDEO_LINE_WIDTH)=*(dest+x+2*VIDEO_LINE_WIDTH+3)=*(dest+x+2*VIDEO_LINE_WIDTH+2)=*(dest+x+2*VIDEO_LINE_WIDTH+1)=*(dest+x+2*VIDEO_LINE_WIDTH)=*(dest+x+VIDEO_LINE_WIDTH+3)=*(dest+x+VIDEO_LINE_WIDTH+2)=*(dest+x+VIDEO_LINE_WIDTH+1)=*(dest+x+VIDEO_LINE_WIDTH)=*(dest+x+3)=*(dest+x+2)=*(dest+x+1)=*(dest+x)=xor_lut[*(dest+x)];
 }
 
 void Vertical_XOR_line_quad(word x_pos,word y_pos,word height)
@@ -158,7 +158,7 @@ void Vertical_XOR_line_quad(word x_pos,word y_pos,word height)
   byte *dest=Screen_pixels+x_pos*ZOOMX+y_pos*VIDEO_LINE_WIDTH*ZOOMY;
   for (i=height;i>0;i--)
   {
-    *(dest+3*VIDEO_LINE_WIDTH+3)=*(dest+3*VIDEO_LINE_WIDTH+2)=*(dest+3*VIDEO_LINE_WIDTH+1)=*(dest+3*VIDEO_LINE_WIDTH)=*(dest+2*VIDEO_LINE_WIDTH+3)=*(dest+2*VIDEO_LINE_WIDTH+2)=*(dest+2*VIDEO_LINE_WIDTH+1)=*(dest+2*VIDEO_LINE_WIDTH)=*(dest+VIDEO_LINE_WIDTH+3)=*(dest+VIDEO_LINE_WIDTH+2)=*(dest+VIDEO_LINE_WIDTH+1)=*(dest+VIDEO_LINE_WIDTH)=*(dest+3)=*(dest+2)=*(dest+1)=*(dest)=~*(dest);
+    *(dest+3*VIDEO_LINE_WIDTH+3)=*(dest+3*VIDEO_LINE_WIDTH+2)=*(dest+3*VIDEO_LINE_WIDTH+1)=*(dest+3*VIDEO_LINE_WIDTH)=*(dest+2*VIDEO_LINE_WIDTH+3)=*(dest+2*VIDEO_LINE_WIDTH+2)=*(dest+2*VIDEO_LINE_WIDTH+1)=*(dest+2*VIDEO_LINE_WIDTH)=*(dest+VIDEO_LINE_WIDTH+3)=*(dest+VIDEO_LINE_WIDTH+2)=*(dest+VIDEO_LINE_WIDTH+1)=*(dest+VIDEO_LINE_WIDTH)=*(dest+3)=*(dest+2)=*(dest+1)=*(dest)=xor_lut[*(dest)];
     dest+=VIDEO_LINE_WIDTH*ZOOMY;
   }
 }
diff --git a/src/pxsimple.c b/src/pxsimple.c
index d00fa142..1e4a95d7 100644
--- a/src/pxsimple.c
+++ b/src/pxsimple.c
@@ -119,7 +119,7 @@ void Horizontal_XOR_line_simple(word x_pos,word y_pos,word width)
   int x;
 
   for (x=0;x<width;x++)
-    *(dest+x)=~*(dest+x);
+    *(dest+x)=xor_lut[*(dest+x)];
 }
 
 void Vertical_XOR_line_simple(word x_pos,word y_pos,word height)
@@ -129,7 +129,7 @@ void Vertical_XOR_line_simple(word x_pos,word y_pos,word height)
   for (i=y_pos;i<y_pos+height;i++)
   {
     color=*(Screen_pixels+x_pos+i*VIDEO_LINE_WIDTH);
-    *(Screen_pixels+x_pos+i*VIDEO_LINE_WIDTH)=~color;
+    *(Screen_pixels+x_pos+i*VIDEO_LINE_WIDTH)=xor_lut[color];
   }
 }
 
diff --git a/src/pxtall.c b/src/pxtall.c
index ad1bfea2..6e867d99 100644
--- a/src/pxtall.c
+++ b/src/pxtall.c
@@ -126,11 +126,11 @@ void Horizontal_XOR_line_tall(word x_pos,word y_pos,word width)
   int x;
 
   for (x=0;x<width;x++)
-    *(dest+x)=~*(dest+x);
+    *(dest+x)=xor_lut[*(dest+x)];
 
   dest=(y_pos*ZOOMY+1)*VIDEO_LINE_WIDTH+x_pos+Screen_pixels;
   for (x=0;x<width;x++)
-    *(dest+x)=~*(dest+x);
+    *(dest+x)=xor_lut[*(dest+x)];
 }
 
 void Vertical_XOR_line_tall(word x_pos,word y_pos,word height)
@@ -140,7 +140,7 @@ void Vertical_XOR_line_tall(word x_pos,word y_pos,word height)
   for (i=y_pos*ZOOMY;i<(y_pos+height)*ZOOMY;i++)
   {
     color=*(Screen_pixels+x_pos+i*VIDEO_LINE_WIDTH);
-    *(Screen_pixels+x_pos+i*VIDEO_LINE_WIDTH)=~color;
+    *(Screen_pixels+x_pos+i*VIDEO_LINE_WIDTH)=xor_lut[color];
   }
 }
 
diff --git a/src/pxtall2.c b/src/pxtall2.c
index a1c9ef0e..66821457 100644
--- a/src/pxtall2.c
+++ b/src/pxtall2.c
@@ -141,7 +141,7 @@ void Horizontal_XOR_line_tall2(word x_pos,word y_pos,word width)
   int x;
 
   for (x=0;x<width*ZOOMX;x+=ZOOMX)
-    *(dest+x+3*VIDEO_LINE_WIDTH+1)=*(dest+x+3*VIDEO_LINE_WIDTH)=*(dest+x+2*VIDEO_LINE_WIDTH+1)=*(dest+x+2*VIDEO_LINE_WIDTH)=*(dest+x+VIDEO_LINE_WIDTH+1)=*(dest+x+VIDEO_LINE_WIDTH)=*(dest+x+1)=*(dest+x)=~*(dest+x);
+    *(dest+x+3*VIDEO_LINE_WIDTH+1)=*(dest+x+3*VIDEO_LINE_WIDTH)=*(dest+x+2*VIDEO_LINE_WIDTH+1)=*(dest+x+2*VIDEO_LINE_WIDTH)=*(dest+x+VIDEO_LINE_WIDTH+1)=*(dest+x+VIDEO_LINE_WIDTH)=*(dest+x+1)=*(dest+x)=xor_lut[*(dest+x)];
 }
 
 void Vertical_XOR_line_tall2(word x_pos,word y_pos,word height)
@@ -150,7 +150,7 @@ void Vertical_XOR_line_tall2(word x_pos,word y_pos,word height)
   byte *dest=Screen_pixels+x_pos*ZOOMX+y_pos*VIDEO_LINE_WIDTH*ZOOMY;
   for (i=height;i>0;i--)
   {
-    *(dest+3*VIDEO_LINE_WIDTH+1)=*(dest+3*VIDEO_LINE_WIDTH)=*(dest+2*VIDEO_LINE_WIDTH+1)=*(dest+2*VIDEO_LINE_WIDTH)=*(dest+VIDEO_LINE_WIDTH+1)=*(dest+VIDEO_LINE_WIDTH)=*(dest+1)=*(dest)=~*(dest);
+    *(dest+3*VIDEO_LINE_WIDTH+1)=*(dest+3*VIDEO_LINE_WIDTH)=*(dest+2*VIDEO_LINE_WIDTH+1)=*(dest+2*VIDEO_LINE_WIDTH)=*(dest+VIDEO_LINE_WIDTH+1)=*(dest+VIDEO_LINE_WIDTH)=*(dest+1)=*(dest)=xor_lut[*(dest)];
     dest+=VIDEO_LINE_WIDTH*ZOOMY;
   }
 }
diff --git a/src/pxtriple.c b/src/pxtriple.c
index 6ca00f91..bcca69dc 100644
--- a/src/pxtriple.c
+++ b/src/pxtriple.c
@@ -140,7 +140,7 @@ void Horizontal_XOR_line_triple(word x_pos,word y_pos,word width)
   int x;
 
   for (x=0;x<width*ZOOMX;x+=ZOOMX)
-    *(dest+x+2*VIDEO_LINE_WIDTH+2)=*(dest+x+2*VIDEO_LINE_WIDTH+1)=*(dest+x+2*VIDEO_LINE_WIDTH)=*(dest+x+VIDEO_LINE_WIDTH+2)=*(dest+x+VIDEO_LINE_WIDTH+1)=*(dest+x+VIDEO_LINE_WIDTH)=*(dest+x+2)=*(dest+x+1)=*(dest+x)=~*(dest+x);
+    *(dest+x+2*VIDEO_LINE_WIDTH+2)=*(dest+x+2*VIDEO_LINE_WIDTH+1)=*(dest+x+2*VIDEO_LINE_WIDTH)=*(dest+x+VIDEO_LINE_WIDTH+2)=*(dest+x+VIDEO_LINE_WIDTH+1)=*(dest+x+VIDEO_LINE_WIDTH)=*(dest+x+2)=*(dest+x+1)=*(dest+x)=xor_lut[*(dest+x)];
 }
 
 void Vertical_XOR_line_triple(word x_pos,word y_pos,word height)
@@ -149,7 +149,7 @@ void Vertical_XOR_line_triple(word x_pos,word y_pos,word height)
   byte *dest=Screen_pixels+x_pos*ZOOMX+y_pos*VIDEO_LINE_WIDTH*ZOOMY;
   for (i=height;i>0;i--)
   {
-    *(dest+2*VIDEO_LINE_WIDTH+2)=*(dest+2*VIDEO_LINE_WIDTH+1)=*(dest+2*VIDEO_LINE_WIDTH)=*(dest+VIDEO_LINE_WIDTH+2)=*(dest+VIDEO_LINE_WIDTH+1)=*(dest+VIDEO_LINE_WIDTH)=*(dest+2)=*(dest+1)=*dest=~*dest;
+    *(dest+2*VIDEO_LINE_WIDTH+2)=*(dest+2*VIDEO_LINE_WIDTH+1)=*(dest+2*VIDEO_LINE_WIDTH)=*(dest+VIDEO_LINE_WIDTH+2)=*(dest+VIDEO_LINE_WIDTH+1)=*(dest+VIDEO_LINE_WIDTH)=*(dest+2)=*(dest+1)=*dest=xor_lut[*dest];
     dest+=VIDEO_LINE_WIDTH*ZOOMY;
   }
 }
diff --git a/src/pxwide.c b/src/pxwide.c
index 761932e6..90761fc7 100644
--- a/src/pxwide.c
+++ b/src/pxwide.c
@@ -129,7 +129,7 @@ void Horizontal_XOR_line_wide(word x_pos,word y_pos,word width)
   int x;
 
   for (x=0;x<width*ZOOMX;x+=ZOOMX)
-    *(dest+x+1)=*(dest+x)=~*(dest+x);
+    *(dest+x+1)=*(dest+x)=xor_lut[*(dest+x)];
 }
 
 void Vertical_XOR_line_wide(word x_pos,word y_pos,word height)
@@ -138,7 +138,7 @@ void Vertical_XOR_line_wide(word x_pos,word y_pos,word height)
   byte *dest=Screen_pixels+x_pos*ZOOMX+y_pos*VIDEO_LINE_WIDTH*ZOOMY;
   for (i=height;i>0;i--)
   {
-    *dest=*(dest+1)=~*dest;
+    *dest=*(dest+1)=xor_lut[*dest];
     dest+=VIDEO_LINE_WIDTH*ZOOMY;
   }
 }
diff --git a/src/pxwide2.c b/src/pxwide2.c
index 868ef942..c8e7be43 100644
--- a/src/pxwide2.c
+++ b/src/pxwide2.c
@@ -137,7 +137,7 @@ void Horizontal_XOR_line_wide2(word x_pos,word y_pos,word width)
   int x;
 
   for (x=0;x<width*ZOOMX;x+=ZOOMX)
-    *(dest+x+VIDEO_LINE_WIDTH+3)=*(dest+x+VIDEO_LINE_WIDTH+2)=*(dest+x+VIDEO_LINE_WIDTH+1)=*(dest+x+VIDEO_LINE_WIDTH)=*(dest+x+3)=*(dest+x+2)=*(dest+x+1)=*(dest+x)=~*(dest+x);
+    *(dest+x+VIDEO_LINE_WIDTH+3)=*(dest+x+VIDEO_LINE_WIDTH+2)=*(dest+x+VIDEO_LINE_WIDTH+1)=*(dest+x+VIDEO_LINE_WIDTH)=*(dest+x+3)=*(dest+x+2)=*(dest+x+1)=*(dest+x)=xor_lut[*(dest+x)];
 }
 
 void Vertical_XOR_line_wide2(word x_pos,word y_pos,word height)
@@ -146,7 +146,7 @@ void Vertical_XOR_line_wide2(word x_pos,word y_pos,word height)
   byte *dest=Screen_pixels+x_pos*ZOOMX+y_pos*VIDEO_LINE_WIDTH*ZOOMY;
   for (i=height;i>0;i--)
   {
-    *(dest+VIDEO_LINE_WIDTH+3)=*(dest+VIDEO_LINE_WIDTH+2)=*(dest+VIDEO_LINE_WIDTH+1)=*(dest+VIDEO_LINE_WIDTH)=*(dest+3)=*(dest+2)=*(dest+1)=*(dest)=~*(dest);
+    *(dest+VIDEO_LINE_WIDTH+3)=*(dest+VIDEO_LINE_WIDTH+2)=*(dest+VIDEO_LINE_WIDTH+1)=*(dest+VIDEO_LINE_WIDTH)=*(dest+3)=*(dest+2)=*(dest+1)=*(dest)=xor_lut[*(dest)];
     dest+=VIDEO_LINE_WIDTH*ZOOMY;
   }
 }
diff --git a/src/readini.c b/src/readini.c
index 0f0f0ac2..91083691 100644
--- a/src/readini.c
+++ b/src/readini.c
@@ -849,14 +849,6 @@ int Load_INI(T_Config * conf)
   else
     conf->Font_file = strdup("font_Dpaint.png");
 
-  conf->Grid_XOR_color=255;
-  // Optional, XOR color for grid overlay (>2.0)
-  if (!Load_INI_get_values (file,buffer,"Grid_XOR_color",1,values))
-  {
-    if ((values[0]>0) && (values[0]<=255))
-      conf->Grid_XOR_color=values[0];
-  }
-
   // Optional, "fake hardware zoom" factor (>2.1)
   if (!Load_INI_get_values (file, buffer,"Pixel_ratio",1,values))
   {
diff --git a/src/saveini.c b/src/saveini.c
index fcd00a7c..46b3f607 100644
--- a/src/saveini.c
+++ b/src/saveini.c
@@ -655,10 +655,6 @@ int Save_INI(T_Config * conf)
   if ((return_code=Save_INI_set_strings (old_file,new_file,buffer,"Font_file",conf->Font_file)))
     goto Erreur_Retour;
 
-  values[0]=(conf->Grid_XOR_color);
-  if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Grid_XOR_color",1,values,0)))
-    goto Erreur_Retour;
-
   values[0]=(Pixel_ratio);
   if ((return_code=Save_INI_set_values (old_file,new_file,buffer,"Pixel_ratio",1,values,0))) {
     DEBUG("saving pixel ratio",return_code);
diff --git a/src/struct.h b/src/struct.h
index 0bd4cb57..a58deed8 100644
--- a/src/struct.h
+++ b/src/struct.h
@@ -363,7 +363,6 @@ typedef struct
   int  Window_pos_y;                     ///< Last window y position (9999 if unsupportd/irrelevant for the platform)
   word Double_click_speed;               ///< Maximum delay for double-click, in ms.
   word Double_key_speed;                 ///< Maximum delay for double-keypress, in ms.
-  byte Grid_XOR_color;                   ///< XOR value to apply for grid color.
   byte Right_click_colorpick;            ///< Boolean, true to enable a "tablet" mode, where RMB acts as instant colorpicker
   byte Sync_views;                       ///< Boolean, true when the Main and Spare should share their viewport settings.
   byte Stylus_mode;                      ///< Boolean, true to tweak some tools (eg:Curve) for single-button stylus.
diff --git a/src/windows.c b/src/windows.c
index 2f2e9e19..42bc54c3 100644
--- a/src/windows.c
+++ b/src/windows.c
@@ -2956,82 +2956,153 @@ void Remap_screen_after_menu_colors_change(void)
 }
 
 
+static int Diff(int i, int j) {
+	int dr = Main_palette[i].R - Main_palette[j].R;
+	int dg = Main_palette[i].G - Main_palette[j].G;
+	int db = Main_palette[i].B - Main_palette[j].B;
+
+	return dr*dr + dg*dg + db*db;
+}
+
+static void compute_xor_table()
+{
+	int i;
+	byte found;
+
+	// Initialize the table with some "random" values
+	for(i = 0; i < 256; i++)
+	{
+		xor_lut[i] = 255 - i;
+	}
+
+	do {
+		// Find the smallest difference in the table
+		//int mindiff = INT_MAX;
+		int idx;
+		/*
+		for(i = 0; i < 256; i++)
+		{
+			int diff = Diff(i, xor_lut[i]);
+			if (diff < mindiff) {
+				idx = i;
+				mindiff = diff;
+			}
+		}*/
+
+		// Try to pair these two colors better
+		found = 0;
+		for(idx = 0; idx < 256; idx++)
+		{
+			int improvement = 0;
+			int betterpair = idx;
+			for(i = 0; i < 256; i++)
+			{
+				// diffs before the swap
+				int before = Diff(idx, xor_lut[idx]) + Diff(i, xor_lut[i]);
+
+				// diffs after the swap
+				int after = Diff(idx, xor_lut[i])  + Diff(i, xor_lut[idx]);
+
+				if (after - before > improvement)
+				{
+					improvement = after - before;
+					betterpair = i;
+				}
+			}
+
+			if (improvement > 0)
+			{
+				// Swapping these colors get us something "more different". Do it !
+				byte idx2 = xor_lut[betterpair];
+				byte i2 = xor_lut[idx];
+
+				xor_lut[betterpair] = i2;
+				xor_lut[i2] = betterpair;
+				xor_lut[idx] = idx2;
+				xor_lut[idx2] = idx;
+
+				found = 1;
+			}
+		}
+	} while(found);
+}
+
 int Same_color(T_Components * palette, byte c1, byte c2)
 {
-  if (palette[c1].R==palette[c2].R &&
-    palette[c1].G==palette[c2].G &&
-    palette[c1].B==palette[c2].B)
-    return 1;
-  return 0;
+	if (palette[c1].R==palette[c2].R &&
+			palette[c1].G==palette[c2].G &&
+			palette[c1].B==palette[c2].B)
+		return 1;
+	return 0;
 }
 
 void Compute_optimal_menu_colors(T_Components * palette)
 {
-  int i;
-  byte l[256];
-  byte s[256];
-  byte h;
-  int max_l = -1, min_l = 256;
-  int low_l, hi_l;
-  int delta_low = 999999;
-  int delta_high = 999999;
-  const int tolerence=16;
-  const T_Components cpc_colors[4] = {
-    {  0,  0,  0},
-    {  0,  0,128}, // Dark blue
-    {128,128,128}, // Grey
-    {255,255,255}
-  };
+	int i;
+	byte l[256];
+	byte s[256];
+	byte h;
+	int max_l = -1, min_l = 256;
+	int low_l, hi_l;
+	int delta_low = 999999;
+	int delta_high = 999999;
+	const int tolerence=16;
+	const T_Components cpc_colors[4] = {
+		{  0,  0,  0},
+		{  0,  0,128}, // Dark blue
+		{128,128,128}, // Grey
+		{255,255,255}
+	};
 
-  Old_black =MC_Black;
-  Old_dark = MC_Dark;
-  Old_light = MC_Light;
-  Old_white = MC_White;
-  Old_trans = MC_Trans;
+	Old_black =MC_Black;
+	Old_dark = MC_Dark;
+	Old_light = MC_Light;
+	Old_white = MC_White;
+	Old_trans = MC_Trans;
 
-  // First method:
-  // If all close matches for the ideal colors exist, pick them.
-  for (i=255; i>=0; i--)
-  {
-    
-    if (Round_palette_component(palette[i].R)/tolerence==Gfx->Default_palette[Gfx->Color[3]].R/tolerence
-     && Round_palette_component(palette[i].G)/tolerence==Gfx->Default_palette[Gfx->Color[3]].G/tolerence
-     && Round_palette_component(palette[i].B)/tolerence==Gfx->Default_palette[Gfx->Color[3]].B/tolerence)
-    {
-      MC_White=i;
-      for (i=255; i>=0; i--)
-      {
-        if (Round_palette_component(palette[i].R)/tolerence==Gfx->Default_palette[Gfx->Color[2]].R/tolerence
-         && Round_palette_component(palette[i].G)/tolerence==Gfx->Default_palette[Gfx->Color[2]].G/tolerence
-         && Round_palette_component(palette[i].B)/tolerence==Gfx->Default_palette[Gfx->Color[2]].B/tolerence)
-        {
-          MC_Light=i;
-          for (i=255; i>=0; i--)
-          {
-            if (Round_palette_component(palette[i].R)/tolerence==Gfx->Default_palette[Gfx->Color[1]].R/tolerence
-             && Round_palette_component(palette[i].G)/tolerence==Gfx->Default_palette[Gfx->Color[1]].G/tolerence
-             && Round_palette_component(palette[i].B)/tolerence==Gfx->Default_palette[Gfx->Color[1]].B/tolerence)
-            {
-              MC_Dark=i;
-              for (i=255; i>=0; i--)
-              {
-                if (Round_palette_component(palette[i].R)/tolerence==Gfx->Default_palette[Gfx->Color[0]].R/tolerence
-                 && Round_palette_component(palette[i].G)/tolerence==Gfx->Default_palette[Gfx->Color[0]].G/tolerence
-                 && Round_palette_component(palette[i].B)/tolerence==Gfx->Default_palette[Gfx->Color[0]].B/tolerence)
-                {
-                  MC_Black=i;
-                  // On cherche une couleur de transparence différente des 4 autres.
-                  for (MC_Trans=0; ((MC_Trans==MC_Black) || (MC_Trans==MC_Dark) ||
-                                   (MC_Trans==MC_Light) || (MC_Trans==MC_White)); MC_Trans++);
-                  // Easy case
-                  MC_OnBlack=MC_Dark;
-                  MC_Window=MC_Light;
-                  MC_Lighter=MC_White;
-                  MC_Darker=MC_Dark;
-                  Remap_menu_sprites();
-                  return;
-                }
-              }
+	// First method:
+	// If all close matches for the ideal colors exist, pick them.
+	for (i=255; i>=0; i--)
+	{
+
+		if (Round_palette_component(palette[i].R)/tolerence==Gfx->Default_palette[Gfx->Color[3]].R/tolerence
+				&& Round_palette_component(palette[i].G)/tolerence==Gfx->Default_palette[Gfx->Color[3]].G/tolerence
+				&& Round_palette_component(palette[i].B)/tolerence==Gfx->Default_palette[Gfx->Color[3]].B/tolerence)
+		{
+			MC_White=i;
+			for (i=255; i>=0; i--)
+			{
+				if (Round_palette_component(palette[i].R)/tolerence==Gfx->Default_palette[Gfx->Color[2]].R/tolerence
+						&& Round_palette_component(palette[i].G)/tolerence==Gfx->Default_palette[Gfx->Color[2]].G/tolerence
+						&& Round_palette_component(palette[i].B)/tolerence==Gfx->Default_palette[Gfx->Color[2]].B/tolerence)
+				{
+					MC_Light=i;
+					for (i=255; i>=0; i--)
+					{
+						if (Round_palette_component(palette[i].R)/tolerence==Gfx->Default_palette[Gfx->Color[1]].R/tolerence
+								&& Round_palette_component(palette[i].G)/tolerence==Gfx->Default_palette[Gfx->Color[1]].G/tolerence
+								&& Round_palette_component(palette[i].B)/tolerence==Gfx->Default_palette[Gfx->Color[1]].B/tolerence)
+						{
+							MC_Dark=i;
+							for (i=255; i>=0; i--)
+							{
+								if (Round_palette_component(palette[i].R)/tolerence==Gfx->Default_palette[Gfx->Color[0]].R/tolerence
+										&& Round_palette_component(palette[i].G)/tolerence==Gfx->Default_palette[Gfx->Color[0]].G/tolerence
+										&& Round_palette_component(palette[i].B)/tolerence==Gfx->Default_palette[Gfx->Color[0]].B/tolerence)
+								{
+									MC_Black=i;
+									// On cherche une couleur de transparence différente des 4 autres.
+									for (MC_Trans=0; ((MC_Trans==MC_Black) || (MC_Trans==MC_Dark) ||
+												(MC_Trans==MC_Light) || (MC_Trans==MC_White)); MC_Trans++);
+									// Easy case
+									MC_OnBlack=MC_Dark;
+									MC_Window=MC_Light;
+									MC_Lighter=MC_White;
+									MC_Darker=MC_Dark;
+									Remap_menu_sprites();
+									return;
+								}
+							}
             }
           }
         }
@@ -3199,6 +3270,7 @@ void Remap_menu_sprites()
 {
   int i, j, k, l;
 
+  compute_xor_table();
   if ( (MC_Light!=Old_light)
     || (MC_Dark!=Old_dark)
     || (MC_White!=Old_white)