Improve auto-detection of menu colors when using very small palettes

git-svn-id: svn://pulkomandy.tk/GrafX2/trunk@1584 416bcca6-2ee7-4201-b75f-2eb2f807beb1

src/engine.c

@@ -1550,7 +1550,7 @@ void Open_window(word width,word height, const char * title)
   Save_background(&(Window_background[Windows_open-1]), Window_pos_X, Window_pos_Y, width, height);
 
   // Fenêtre grise
-  Block(Window_pos_X+(Menu_factor_X<<1),Window_pos_Y+(Menu_factor_Y<<1),(width-4)*Menu_factor_X,(height-4)*Menu_factor_Y,MC_Light);
+  Block(Window_pos_X+(Menu_factor_X<<1),Window_pos_Y+(Menu_factor_Y<<1),(width-4)*Menu_factor_X,(height-4)*Menu_factor_Y,MC_Window);
 
   // -- Frame de la fenêtre ----- --- -- -  -
 
@@ -1852,7 +1852,7 @@ void Window_draw_slider(T_Scroller_button * button)
 
   Block(Window_pos_X+(button->Pos_X*Menu_factor_X),
         Window_pos_Y+(slider_position*Menu_factor_Y),
-        11*Menu_factor_X,button->Cursor_height*Menu_factor_Y,MC_Dark/*MC_White*/);
+        11*Menu_factor_X,button->Cursor_height*Menu_factor_Y,MC_OnBlack/*MC_White*/);
 
   Update_rect(Window_pos_X+(button->Pos_X*Menu_factor_X),
         Window_pos_Y+button->Pos_Y*Menu_factor_Y,

src/global.h

@@ -73,6 +73,12 @@ GFX2_GLOBAL byte MC_Light; ///< Index of color to use as "light grey" in the GUI
 GFX2_GLOBAL byte MC_White; ///< Index of color to use as "white" in the GUI menus.
 GFX2_GLOBAL byte MC_Trans; ///< Index of color to use as "transparent" while loading the GUI file.
 
+GFX2_GLOBAL byte MC_OnBlack; ///< Index of color immediately lighter than "black" in the GUI menus.
+GFX2_GLOBAL byte MC_Window; ///< Index of color to use as window background in the GUI menus.
+GFX2_GLOBAL byte MC_Lighter; ///< Index of color lighter than window in the GUI menus.
+GFX2_GLOBAL byte MC_Darker; ///< Index of color darker than window in the GUI menus.
+
+
 // Input state
 GFX2_GLOBAL word Mouse_X; ///< Current mouse cursor position.
 GFX2_GLOBAL word Mouse_Y; ///< Current mouse cursor position.

src/init.c

@@ -2682,6 +2682,11 @@ void Set_current_skin(const char *skinfile, T_Gui_skin *gfx)
   MC_Light = gfx->Color[2];
   MC_White = gfx->Color[3];
   MC_Trans = gfx->Color_trans;
+  MC_OnBlack=MC_Dark;
+  MC_Window=MC_Light;
+  MC_Lighter=MC_White;
+  MC_Darker=MC_Dark;
+  
 
   // Set menubars to point to the new data
   for (i=0; i<3; i++)

src/windows.c

@@ -2738,7 +2738,14 @@ void Remap_screen_after_menu_colors_change(void)
 }
 
 
-
+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;
+}
 
 void Compute_optimal_menu_colors(T_Components * palette)
 {
@@ -2746,9 +2753,10 @@ void Compute_optimal_menu_colors(T_Components * palette)
   byte l[256];
   byte s[256];
   byte h;
-  byte max_l = 0, min_l = 255;
+  int max_l = -1, min_l = 256;
-  byte low_l, hi_l;
+  int low_l, hi_l;
-  byte delta_low = 255, delta_hi = 255;
+  int delta_low = 999999;
+  int delta_high = 999999;
 
   Old_black =MC_Black;
   Old_dark = MC_Dark;
@@ -2790,7 +2798,11 @@ void Compute_optimal_menu_colors(T_Components * palette)
                   // 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;
                 }
@@ -2805,50 +2817,86 @@ void Compute_optimal_menu_colors(T_Components * palette)
 
   // Compute luminance for whole palette
   // Take the darkest as black, the brightest white
-  for(i = 0; i < 256; i++) {
+  for(i = 0; i < 256; i++)
+  {
     RGB_to_HSL(palette[i].R, palette[i].G, palette[i].B, &h, &s[i], &l[i]);
-    if (l[i] > max_l) {
+    if (l[i] > max_l)
+    {
       max_l = l[i];
       MC_White = i;
     }
-
+  }
-    if (l[i] < min_l) {
+  for(i = 0; i < 256; i++)
+  {
+    if (l[i] < min_l && i!=MC_White)
+    {
       min_l = l[i];
       MC_Black = i;
     }
   }
 
-  // Find colors nearest to min+(max-min)/3 and min+2(max-min)/3
+  // Find color nearest to min+2(max-min)/3
   // but at the same time we try to minimize the saturation so that the menu
   // still looks grey
-  low_l = min_l + (max_l - min_l)/3;
   hi_l = min_l + 2*(max_l - min_l)/3;
 
-  for (i = 0; i < 256; i++) {
+  for (i = 0; i < 256; i++)
-    if ( abs(l[i] - low_l) + s[i]/2 < delta_low ) {
+  {
-      delta_low = abs(l[i] - low_l);
+    if ( abs(l[i] - hi_l) + s[i]/4 < delta_high && i!=MC_White && i!=MC_Black)
-      MC_Dark = i;
+    {
-    }
+      delta_high = abs(l[i] - hi_l) + s[i]/4;
-
-    if ( abs(l[i] - hi_l) + s[i]/3 < delta_hi ) {
-      delta_hi = abs(l[i] - hi_l);
       MC_Light = i;
     }
   }
   
+  // Target "Dark color" is halfway between Light and Black
+  low_l = ((int)l[MC_Light]+l[MC_Black])/2;
+  for (i = 0; i < 256; i++)
+  {
+    if ( abs((int)l[i] - low_l) + s[i]/4 < delta_low && i!=MC_White && i!=MC_Black && i!=MC_Light)
+    {
+      delta_low = abs((int)l[i] - low_l)+ s[i]/4;
+      MC_Dark = i;
+    }
+  }
+  
+  
+  //if (l[MC_Light]<l[MC_Dark])
+  //{
+  //  // Not sure if that can happen, but just in case:
+  //  SWAP_BYTES(MC_Light, MC_Dark)
+  //}
+
   // Si deux des couleurs choisies ont le même index, c'est destructif car 
   // on fait ensuite un remap de l'image. Donc on évite ce problème (un
   // peu brutalement)
   // On commence par déplacer les gris, comme ça on a plus de chances de garder au moins
   // le blanc et le noir
-  while (MC_Dark == MC_Light || MC_Dark == MC_White || MC_Black == MC_Dark) MC_Dark--;
+  //while (MC_Dark == MC_Light || MC_Dark == MC_White || MC_Black == MC_Dark || Same_color(palette, MC_Dark, MC_White)) MC_Dark--;
-  while (MC_White == MC_Light || MC_Dark == MC_Light || MC_Black == MC_Light) MC_Light--;
+  //while (MC_White == MC_Light || MC_Dark == MC_Light || MC_Black == MC_Light || Same_color(palette, MC_Light, MC_Black)) MC_Light--;
-  while (MC_White == MC_Light || MC_Dark == MC_White || MC_Black == MC_White) MC_White--;
+  //while (MC_White == MC_Light || MC_Dark == MC_White || MC_Black == MC_White) MC_White--;
 
   // 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++);
   
+  if (Same_color(palette, MC_Black, MC_Dark))
+    MC_OnBlack=MC_Light;
+  else
+    MC_OnBlack=MC_Dark;
+  
+  if (Same_color(palette, MC_White, MC_Light))
+  {
+    MC_Window=MC_Dark;
+    MC_Darker=MC_Black;
+  }
+  else
+  {
+    MC_Window=MC_Light;
+    MC_Darker=MC_Dark;
+  }
+  MC_Lighter=MC_White;
+  
   Remap_menu_sprites();
 }