Remove now-redundant blend code.

OpenRA.Game/Graphics/IGraphicsDevice.cs

@@ -41,8 +41,6 @@ namespace OpenRA
 		Additive,
 		Subtractive,
 		Multiply,
-		SoftAdditive,
-		Translucency,
 		Multiplicative,
 		DoubleMultiplicative
 	}
@@ -70,7 +68,7 @@ namespace OpenRA
 		void EnableDepthBuffer();
 		void DisableDepthBuffer();
 
-		void SetBlendMode(BlendMode mode, float alpha = 1f);
+		void SetBlendMode(BlendMode mode);
 
 		void GrabWindowMouseFocus();
 		void ReleaseWindowMouseFocus();

OpenRA.Game/Graphics/Sprite.cs

@@ -17,7 +17,6 @@ namespace OpenRA.Graphics
 		public readonly Rectangle Bounds;
 		public readonly Sheet Sheet;
 		public readonly BlendMode BlendMode;
-		public readonly float Alpha;
 		public readonly TextureChannel Channel;
 		public readonly float2 Size;
 		public readonly float2 Offset;
@@ -27,7 +26,7 @@ namespace OpenRA.Graphics
 		public Sprite(Sheet sheet, Rectangle bounds, TextureChannel channel)
 			: this(sheet, bounds, float2.Zero, channel) { }
 
-		public Sprite(Sheet sheet, Rectangle bounds, float2 offset, TextureChannel channel, BlendMode blendMode = BlendMode.Alpha, float alpha = 1f)
+		public Sprite(Sheet sheet, Rectangle bounds, float2 offset, TextureChannel channel, BlendMode blendMode = BlendMode.Alpha)
 		{
 			Sheet = sheet;
 			Bounds = bounds;
@@ -35,7 +34,6 @@ namespace OpenRA.Graphics
 			Channel = channel;
 			Size = new float2(bounds.Size);
 			BlendMode = blendMode;
-			Alpha = alpha;
 
 			FractionalOffset = offset / Size;
 

OpenRA.Game/Graphics/SpriteRenderer.cs

@@ -21,7 +21,6 @@ namespace OpenRA.Graphics
 		readonly Vertex[] vertices;
 		Sheet currentSheet;
 		BlendMode currentBlend = BlendMode.Alpha;
-		float currentAlpha = 1f;
 		int nv = 0;
 
 		public SpriteRenderer(Renderer renderer, IShader shader)
@@ -37,14 +36,14 @@ namespace OpenRA.Graphics
 			{
 				shader.SetTexture("DiffuseTexture", currentSheet.GetTexture());
 
-				renderer.Device.SetBlendMode(currentBlend, currentAlpha);
+				renderer.Device.SetBlendMode(currentBlend);
 				shader.Render(() =>
 				{
 					var vb = renderer.GetTempVertexBuffer();
 					vb.SetData(vertices, nv);
 					renderer.DrawBatch(vb, 0, nv, PrimitiveType.QuadList);
 				});
-				renderer.Device.SetBlendMode(BlendMode.None, currentAlpha);
+				renderer.Device.SetBlendMode(BlendMode.None);
 
 				nv = 0;
 				currentSheet = null;
@@ -55,10 +54,9 @@ namespace OpenRA.Graphics
 		{
 			renderer.CurrentBatchRenderer = this;
 
-			if (s.Alpha != currentAlpha || s.BlendMode != currentBlend || s.Sheet != currentSheet || nv + 4 > renderer.TempBufferSize)
+			if (s.BlendMode != currentBlend || s.Sheet != currentSheet || nv + 4 > renderer.TempBufferSize)
 				Flush();
 
-			currentAlpha = s.Alpha;
 			currentBlend = s.BlendMode;
 			currentSheet = s.Sheet;
 		}

OpenRA.Mods.Common/Graphics/DefaultSpriteSequence.cs

@@ -119,13 +119,12 @@ namespace OpenRA.Mods.Common.Graphics
 
 				var offset = LoadField<float2>(d, "Offset", float2.Zero);
 				var blendMode = LoadField<BlendMode>(d, "BlendMode", BlendMode.Alpha);
-				var alpha = LoadField<float>(d, "Alpha", 1f);
 
 				// Apply offset to each sprite in the sequence
 				// Different sequences may apply different offsets to the same frame
 				var src = GetSpriteSrc(modData, tileSet, sequence, animation, info.Value, d);
 				sprites = cache[src].Select(
-					s => new Sprite(s.Sheet, s.Bounds, s.Offset + offset, s.Channel, blendMode, alpha)).ToArray();
+					s => new Sprite(s.Sheet, s.Bounds, s.Offset + offset, s.Channel, blendMode)).ToArray();
 
 				MiniYaml length;
 				if (d.TryGetValue("Length", out length) && length.Value == "*")

OpenRA.Renderer.Null/NullGraphicsDevice.cs

@@ -43,7 +43,7 @@ namespace OpenRA.Renderer.Null
 		public void EnableDepthBuffer() { }
 		public void DisableDepthBuffer() { }
 
-		public void SetBlendMode(BlendMode mode, float alpha = 1f) { }
+		public void SetBlendMode(BlendMode mode) { }
 
 		public void GrabWindowMouseFocus() { }
 		public void ReleaseWindowMouseFocus() { }

OpenRA.Renderer.Sdl2/Sdl2GraphicsDevice.cs

@@ -246,7 +246,7 @@ namespace OpenRA.Renderer.Sdl2
 			ErrorHandler.CheckGlError();
 		}
 
-		public void SetBlendMode(BlendMode mode, float alpha = 1f)
+		public void SetBlendMode(BlendMode mode)
 		{
 			GL.BlendEquation(BlendEquationMode.FuncAdd);
 			ErrorHandler.CheckGlError();
@@ -262,16 +262,16 @@ namespace OpenRA.Renderer.Sdl2
 					GL.BlendFunc(BlendingFactorSrc.One, BlendingFactorDest.OneMinusSrcAlpha);
 					break;
 				case BlendMode.Additive:
-					GL.Enable(EnableCap.Blend);
-					ErrorHandler.CheckGlError();
-					GL.BlendFunc(BlendingFactorSrc.One, BlendingFactorDest.One);
-					break;
 				case BlendMode.Subtractive:
 					GL.Enable(EnableCap.Blend);
 					ErrorHandler.CheckGlError();
 					GL.BlendFunc(BlendingFactorSrc.One, BlendingFactorDest.One);
-					ErrorHandler.CheckGlError();
+					if (mode == BlendMode.Subtractive)
-					GL.BlendEquation(BlendEquationMode.FuncReverseSubtract);
+					{
+						ErrorHandler.CheckGlError();
+						GL.BlendEquation(BlendEquationMode.FuncReverseSubtract);
+					}
+
 					break;
 				case BlendMode.Multiply:
 					GL.Enable(EnableCap.Blend);
@@ -279,17 +279,6 @@ namespace OpenRA.Renderer.Sdl2
 					GL.BlendFunc(BlendingFactorSrc.DstColor, BlendingFactorDest.OneMinusSrcAlpha);
 					ErrorHandler.CheckGlError();
 					break;
-				case BlendMode.SoftAdditive:
-					GL.Enable(EnableCap.Blend);
-					ErrorHandler.CheckGlError();
-					GL.BlendFunc(BlendingFactorSrc.OneMinusDstColor, BlendingFactorDest.One);
-					break;
-				case BlendMode.Translucency:
-					GL.Enable(EnableCap.Blend);
-					ErrorHandler.CheckGlError();
-					GL.BlendFunc(BlendingFactorSrc.OneMinusConstantAlpha, BlendingFactorDest.One);
-					ErrorHandler.CheckGlError();
-					break;
 				case BlendMode.Multiplicative:
 					GL.Enable(EnableCap.Blend);
 					ErrorHandler.CheckGlError();
@@ -302,9 +291,6 @@ namespace OpenRA.Renderer.Sdl2
 					break;
 			}
 
-			if (alpha != 1f)
-				GL.BlendColor(1f, 1f, 1f, alpha);
-
 			ErrorHandler.CheckGlError();
 		}