Fix Lua function matchcolor2() inaccuracies caused by integer arithmetics

git-svn-id: svn://pulkomandy.tk/GrafX2/trunk@2082 416bcca6-2ee7-4201-b75f-2eb2f807beb1

src/Makefile.dep

@@ -19,7 +19,7 @@ $(OBJDIR)/factory.o: factory.c brush.h struct.h const.h buttons.h engine.h error
  filesel.h loadsave.h global.h graph.h io.h misc.h pages.h readline.h \
  sdlscreen.h windows.h palette.h input.h help.h realpath.h setup.h \
  tiles.h
-$(OBJDIR)/factory_gui.o: factory_gui.c brush.h struct.h const.h buttons.h engine.h \
+$(OBJDIR)/factory_m.o: factory_m.c brush.h struct.h const.h buttons.h engine.h \
  errors.h filesel.h loadsave.h global.h graph.h io.h misc.h pages.h \
  readline.h sdlscreen.h windows.h palette.h input.h help.h realpath.h \
  setup.h tiles.h
@@ -72,9 +72,6 @@ $(OBJDIR)/pages.o: pages.c global.h struct.h const.h pages.h errors.h loadsave.h
 $(OBJDIR)/palette.o: palette.c const.h struct.h global.h misc.h engine.h readline.h \
  buttons.h pages.h help.h sdlscreen.h errors.h op_c.h colorred.h \
  windows.h input.h palette.h shade.h
-$(OBJDIR)/palette_test.o: palette_test.c const.h struct.h global.h misc.h engine.h \
- readline.h buttons.h pages.h help.h sdlscreen.h errors.h op_c.h \
- colorred.h windows.h input.h palette.h shade.h
 $(OBJDIR)/pversion.o: pversion.c
 $(OBJDIR)/pxdouble.o: pxdouble.c global.h struct.h const.h sdlscreen.h misc.h \
  graph.h pxdouble.h pxwide.h

src/factory.c

@@ -860,7 +860,8 @@ int L_MatchColor(lua_State* L)
 int L_MatchColor2(lua_State* L)
 {
   double r, g, b;
-  int c;
+  double l_weight = 0.25;
+  byte best_color = 0;
   int nb_args=lua_gettop(L);
 
   if (nb_args < 3 || nb_args > 4)
@@ -870,17 +871,67 @@ int L_MatchColor2(lua_State* L)
   LUA_ARG_NUMBER(1, "matchcolor2", r, -DBL_MAX, DBL_MAX);
   LUA_ARG_NUMBER(2, "matchcolor2", g, -DBL_MAX, DBL_MAX);
   LUA_ARG_NUMBER(3, "matchcolor2", b, -DBL_MAX, DBL_MAX);
-  if (nb_args == 3)
+  if (nb_args > 3)
   {
-    c = Best_color_perceptual(clamp_byte(r),clamp_byte(g),clamp_byte(b));
+    LUA_ARG_NUMBER(4, "matchcolor2", l_weight, 0.0, 1.0);
   }
-  else // nb_args == 4
+  
+  // Similar to Best_color_perceptual(), but with floating point
   {
-    float weight;
+    int col;  
-    LUA_ARG_NUMBER(4, "matchcolor2", weight, -DBL_MAX, DBL_MAX);
+    double best_diff=9e99;
-    c = Best_color_perceptual_weighted(clamp_byte(r),clamp_byte(g),clamp_byte(b),weight);
+    double target_bri;
+    double bri;
+    double diff_b, diff_c, diff;
+  
+    if (r<0.0)
+      r=0;
+    else if (r>255.0)
+      r=255.0;
+    if (g<0.0)
+      g=0;
+    else if (g>255.0)
+      g=255.0;
+    if (b<0.0)
+      b=0;
+    else if (b>255.0)
+      b=255.0;
+  
+    // Similar to Perceptual_lightness();
+    target_bri = sqrt(0.26*r*0.26*r + 0.55*g*0.55*g + 0.19*b*0.19*b);
+    
+    for (col=0; col<256; col++)
+    {
+      if (Exclude_color[col])
+        continue;
+  
+      diff_c = sqrt(
+        (0.26*(Main_palette[col].R-r))*
+        (0.26*(Main_palette[col].R-r))+
+        (0.55*(Main_palette[col].G-g))*
+        (0.55*(Main_palette[col].G-g))+
+        (0.19*(Main_palette[col].B-b))*
+        (0.19*(Main_palette[col].B-b)));
+      // Exact match
+      if (diff_c<1.0)
+      {
+          lua_pushinteger(L, col);
+          return 1;
+      }
+  
+      bri = sqrt(0.26*0.26*(Main_palette[col].R*Main_palette[col].R) + 0.55*0.55*(Main_palette[col].G*Main_palette[col].G) + 0.19*0.19*(Main_palette[col].B*Main_palette[col].B));
+      diff_b = fabs(target_bri-bri);
+  
+      diff=l_weight*(diff_b-diff_c)+diff_c;
+      if (diff<best_diff)
+      {
+        best_diff=diff;
+        best_color=col;
+      } 
+    }
   }
-  lua_pushinteger(L, c);
+  
+  lua_pushinteger(L, best_color);
   return 1;
 }
 

src/windows.c

@@ -2793,49 +2793,6 @@ byte Best_color_perceptual(byte r,byte g,byte b)
   return best_color;
 }
 
-byte Best_color_perceptual_weighted(byte r,byte g,byte b,float l_weight)
-{
-  
-  int col;  
-  float best_diff=255.0*1.56905;
-  byte  best_color=0;
-  float target_bri;
-  float bri;
-  float diff_b, diff_c, diff;
-
-  // Similar to Perceptual_lightness();
-  target_bri = sqrt(0.26*r*0.26*r + 0.55*g*0.55*g + 0.19*b*0.19*b);
-  
-  for (col=0; col<256; col++)
-  {
-    if (Exclude_color[col])
-      continue;
-
-    diff_c = sqrt(
-      (0.26*(Main_palette[col].R-r))*
-      (0.26*(Main_palette[col].R-r))+
-      (0.55*(Main_palette[col].G-g))*
-      (0.55*(Main_palette[col].G-g))+
-      (0.19*(Main_palette[col].B-b))*
-      (0.19*(Main_palette[col].B-b)));
-    // Exact match
-    if (diff_c==0)
-      return col;
-
-    bri = sqrt(0.26*Main_palette[col].R*0.26*Main_palette[col].R + 0.55*Main_palette[col].G*0.55*Main_palette[col].G + 0.19*Main_palette[col].B*0.19*Main_palette[col].B);
-    diff_b = abs(target_bri-bri);
-
-    diff=l_weight*(diff_b-diff_c)+diff_c;
-    if (diff<best_diff)
-    {
-      best_diff=diff;
-      best_color=col;
-    } 
-  }
-
-  return best_color;
-}
-
 byte Best_color_perceptual_except(byte r,byte g,byte b, byte except)
 {
   

src/windows.h

@@ -102,7 +102,6 @@ byte Best_color_nonexcluded(byte red,byte green,byte blue);
 byte Best_color_range(byte red,byte green,byte blue,byte max);
 byte Best_color_perceptual(byte r,byte g,byte b);
 byte Best_color_perceptual_except(byte r,byte g,byte b, byte except);
-byte Best_color_perceptual_weighted(byte r,byte g,byte b, float weight);
 
 void Horizontal_XOR_line_zoom(short x_pos, short y_pos, short width);
 void Vertical_XOR_line_zoom(short x_pos, short y_pos, short height);