Merge pull request #262 from UnityTech/antialias

Antialias

Author: zhuxingwei

Runtime/Resources/UIWidgets_canvas.cginc

@@ -3,6 +3,7 @@ float _mat[9];
 
 half4 _color;
 fixed _alpha;
+fixed _strokeMult;
 half4x4 _shaderMat;
 sampler2D _shaderTex;
 half4 _leftColor;
@@ -178,3 +179,11 @@ fixed4 frag_mf (v2f i) : SV_Target {
 
      return color;
 }
+
+float strokeMask(float u, float v) {
+    return min(1.0, (1.0 - abs(u * 2.0 - 1.0)) * 1.0) * min(1.0, v);
+}
+
+fixed4 frag_stroke_alpha(v2f i) : SV_Target {
+    return shader_color(i) * strokeMask(i.ftcoord.x, i.ftcoord.y);
+}

Runtime/Resources/UIWidgets_canvas_strokeAlpha.shader

@@ -0,0 +1,65 @@
+Shader "UIWidgets/canvas_strokeAlpha"
+{
+    Properties {
+       _SrcBlend("_SrcBlend", Int) = 1 // One
+       _DstBlend("_DstBlend", Int) = 10 // OneMinusSrcAlpha
+       _StencilComp("_StencilComp", Float) = 3 // - Equal, 8 - Always 
+    }
+   
+    SubShader {
+        ZTest Always
+        ZWrite Off
+        Blend [_SrcBlend] [_DstBlend]
+        
+        Stencil {
+            Ref 128
+            Comp [_StencilComp]
+            Pass IncrSat
+        }
+
+        Pass { // 0, color
+            CGPROGRAM
+            #define UIWIDGETS_COLOR
+            #include "UIWidgets_canvas.cginc"
+            #pragma vertex vert
+            #pragma fragment frag_stroke_alpha
+            ENDCG
+        }
+        
+        Pass { // 1, linear
+            CGPROGRAM
+            #define UIWIDGETS_LINEAR
+            #include "UIWidgets_canvas.cginc"
+            #pragma vertex vert
+            #pragma fragment frag_stroke_alpha
+            ENDCG
+        }
+
+        Pass { // 2, radial
+            CGPROGRAM
+            #define UIWIDGETS_RADIAL
+            #include "UIWidgets_canvas.cginc"
+            #pragma vertex vert
+            #pragma fragment frag_stroke_alpha
+            ENDCG
+        }
+
+        Pass { // 3, sweep
+            CGPROGRAM
+            #define UIWIDGETS_SWEEP
+            #include "UIWidgets_canvas.cginc"
+            #pragma vertex vert
+            #pragma fragment frag_stroke_alpha
+            ENDCG
+        }
+        
+        Pass { // 4, image
+            CGPROGRAM
+            #define UIWIDGETS_IMAGE
+            #include "UIWidgets_canvas.cginc"
+            #pragma vertex vert
+            #pragma fragment frag_stroke_alpha
+            ENDCG
+        }
+    }
+}