Expand UDMF and ZScript API for side's own additive colors

Add 'useowncoloradd_{top,mid,bottom}' sidedef properties to the UDMF 
spec
Only use side's additive colors if 'useowncoloradd_(top|mid|bottom)' is 
set.
Rename UseOwnColors flag to UseOwnSpecialColors
Add UseOwnAdditiveColor flag to side_t::part
Add EnableAdditiveColor to side_t
Add Side.EnableAdditiveColor to ZScript API

specs/udmf_zdoom.txt

@@ -201,9 +201,12 @@ Note: All <bool> fields default to false unless mentioned otherwise.
 	  uppercolor_bottom = <int>;    // Material color of the top of the lower tier.
 	  lowercolor_bottom = <int>;    // Material color of the bottom of the lower tier. (Hardware rendering only.)
 
-      coloradd_top = <int>;         // Additive material color to apply to top section of sidedef. Takes precedence over sector setting. Default is black (0x000000)
+      useowncoloradd_top = <bool>;  // Whether or not to use the given additive color for the top section of the sidedef.
-      coloradd_mid = <int>;         // Additive material color to apply to middle section of sidedef. Takes precedence over sector setting. Default is black (0x000000)
+      coloradd_top = <int>;         // Additive material color to apply to top section of sidedef. Default is black (0x000000)
-      coloradd_bottom = <int>;      // Additive material color to apply to bottom section of sidedef. Takes precedence over sector setting. Default is black (0x000000)
+      useowncoloradd_mid = <bool>;  // Whether or not to use the given additive color for the middle section of the sidedef.
+      coloradd_mid = <int>;         // Additive material color to apply to middle section of sidedef. Default is black (0x000000)
+      useowncoloradd_bottom = <bool>;  // Whether or not to use the given additive color for the bottom section of the sidedef.
+      coloradd_bottom = <int>;      // Additive material color to apply to bottom section of sidedef. Default is black (0x000000)
    }
 
    sector

src/namedef.h

@@ -663,8 +663,11 @@ xx(clampgradient_bottom)
 xx(useowncolors_bottom)
 xx(uppercolor_bottom)
 xx(lowercolor_bottom)
+xx(useowncoloradd_top)
 xx(coloradd_top)
+xx(useowncoloradd_mid)
 xx(coloradd_mid)
+xx(useowncoloradd_bottom)
 xx(coloradd_bottom)
 
 xx(Renderstyle)

src/p_udmf.cpp

@@ -1332,7 +1332,7 @@ public:
 				break;
 
 			case NAME_useowncolors_top:
-				Flag(sd->textures[side_t::top].flags, side_t::part::UseOwnColors, key);
+				Flag(sd->textures[side_t::top].flags, side_t::part::UseOwnSpecialColors, key);
 				break;
 
 			case NAME_uppercolor_top:
@@ -1356,7 +1356,7 @@ public:
 				break;
 
 			case NAME_useowncolors_mid:
-				Flag(sd->textures[side_t::mid].flags, side_t::part::UseOwnColors, key);
+				Flag(sd->textures[side_t::mid].flags, side_t::part::UseOwnSpecialColors, key);
 				break;
 
 			case NAME_uppercolor_mid:
@@ -1380,7 +1380,7 @@ public:
 				break;
 
 			case NAME_useowncolors_bottom:
-				Flag(sd->textures[side_t::bottom].flags, side_t::part::UseOwnColors, key);
+				Flag(sd->textures[side_t::bottom].flags, side_t::part::UseOwnSpecialColors, key);
 				break;
 
 			case NAME_uppercolor_bottom:
@@ -1403,6 +1403,14 @@ public:
 				sd->SetAdditiveColor(side_t::bottom, CheckInt(key));
 				break;
 
+			case NAME_useowncoloradd_top:
+				sd->textures[side_t::top].flags |= side_t::part::UseOwnAdditiveColor * CheckBool(key);
+
+			case NAME_useowncoloradd_mid:
+				sd->textures[side_t::mid].flags |= side_t::part::UseOwnAdditiveColor * CheckBool(key);
+
+			case NAME_useowncoloradd_bottom:
+				sd->textures[side_t::bottom].flags |= side_t::part::UseOwnAdditiveColor * CheckBool(key);
 
 			default:
 				break;

src/r_defs.h

@@ -1160,7 +1160,8 @@ struct side_t
 			NoGradient = 1,
 			FlipGradient = 2,
 			ClampGradient = 4,
-			UseOwnColors = 8,
+			UseOwnSpecialColors = 8,
+			UseOwnAdditiveColor = 16,
 		};
 		double xOffset;
 		double yOffset;
@@ -1311,22 +1312,37 @@ struct side_t
 		auto &part = textures[which];
 		if (part.flags & part::NoGradient) slot = 0;
 		if (part.flags & part::FlipGradient) slot ^= 1;
-		return (part.flags & part::UseOwnColors) ? part.SpecialColors[slot] : frontsector->SpecialColors[sector_t::walltop + slot];
+		return (part.flags & part::UseOwnSpecialColors) ? part.SpecialColors[slot] : frontsector->SpecialColors[sector_t::walltop + slot];
 	}
 
-	void SetAdditiveColor(int which, PalEntry rgb, bool use = true)
+	void EnableAdditiveColor(int which, bool enable)
 	{
-		rgb.a = use ? 255 : 0;
+		int flag = enable ? part::UseOwnAdditiveColor : 0;
+		if (enable)
+		{
+			textures[which].flags |= flag;
+		}
+		else
+		{
+			textures[which].flags &= (~flag);
+		}
+	}
+
+	void SetAdditiveColor(int which, PalEntry rgb)
+	{
+		rgb.a = 255;
 		textures[which].AdditiveColor = rgb;
 	}
 
 	PalEntry GetAdditiveColor(int which, sector_t *frontsector) const
 	{
-		auto &color = textures[which].AdditiveColor;
+		if (textures[which].flags & part::UseOwnAdditiveColor) {
-		if (color.a == 0) {
+			return textures[which].AdditiveColor;
+		}
+		else
+		{
 			return frontsector->AdditiveColors[sector_t::walltop]; // Used as additive color for all walls
 		}
-		return color;
 	}
 
 	DInterpolation *SetInterpolation(int position);

src/scripting/vmthunks.cpp

@@ -1649,11 +1649,11 @@ DEFINE_ACTION_FUNCTION_NATIVE(_Sector, RemoveForceField, RemoveForceField)
 	 return 0;
  }
 
- static void SetSideAdditiveColor(side_t *self, int tier, int color, bool use)
+ static void SetSideAdditiveColor(side_t *self, int tier, int color)
  {
 	 if (tier >= 0 && tier < 3)
 	 {
-		 self->SetAdditiveColor(tier, color, use);
+		 self->SetAdditiveColor(tier, color);
 	 }
  }
 
@@ -1662,8 +1662,24 @@ DEFINE_ACTION_FUNCTION_NATIVE(_Sector, RemoveForceField, RemoveForceField)
 	 PARAM_SELF_STRUCT_PROLOGUE(side_t);
 	 PARAM_INT(tier);
 	 PARAM_COLOR(color);
-	 PARAM_BOOL(use);
+	 SetSideAdditiveColor(self, tier, color);
-	 SetSideAdditiveColor(self, tier, color, use);
+	 return 0;
+ }
+
+ static void EnableSideAdditiveColor(side_t *self, int tier, bool enable)
+ {
+	 if (tier >= 0 && tier < 3)
+	 {
+		 self->EnableAdditiveColor(tier, enable);
+	 }
+ }
+
+ DEFINE_ACTION_FUNCTION_NATIVE(_Side, EnableAdditiveColor, EnableSideAdditiveColor)
+ {
+	 PARAM_SELF_STRUCT_PROLOGUE(side_t);
+	 PARAM_INT(tier);
+	 PARAM_BOOL(enable);
+	 EnableSideAdditiveColor(self, tier, enable);
 	 return 0;
  }
 

wadsrc/static/zscript/mapdata.zs

@@ -87,7 +87,8 @@ struct Side native play
 	native void MultiplyTextureYScale(int which, double delta);
 	native void SetSpecialColor(int tier, int position, Color scolor);
 	native Color GetAdditiveColor(int tier);
-	native void SetAdditiveColor(int tier, Color color, bool use = true);
+	native void SetAdditiveColor(int tier, Color color);
+	native void EnableAdditiveColor(int tier, bool enable);
 	//native DInterpolation *SetInterpolation(int position);
 	//native void StopInterpolation(int position);