SoftMaskForUGUI/SoftMask.cginc

49 lines
1.3 KiB
HLSL

#ifndef UI_SOFTMASK_INCLUDED
#define UI_SOFTMASK_INCLUDED
sampler2D _SoftMaskTex;
float _Stencil;
float4x4 _SceneView;
float4x4 _SceneProj;
half4 _MaskInteraction;
fixed Approximately(float4x4 a, float4x4 b)
{
float4x4 d = abs(a - b);
return step(
max(d._m00,max(d._m01,max(d._m02,max(d._m03,
max(d._m10,max(d._m11,max(d._m12,max(d._m13,
max(d._m20,max(d._m21,max(d._m22,max(d._m23,
max(d._m30,max(d._m31,max(d._m32,d._m33))))))))))))))),
0.01);
}
fixed GetMaskAlpha(fixed alpha, fixed stencilId, fixed interaction)
{
fixed onStencil = step(stencilId, _Stencil);
alpha = lerp(1, alpha, onStencil * step(1, interaction));
return lerp(alpha, 1 - alpha, onStencil * step(2, interaction));
}
half SoftMask(float4 clipPos)
{
half2 view = clipPos.xy/_ScreenParams.xy;
#if UNITY_UV_STARTS_AT_TOP
view.y = 1.0 - view.y;
#endif
fixed4 mask = tex2D(_SoftMaskTex, view);
half alpha = GetMaskAlpha(mask.x, 1, _MaskInteraction.x)
* GetMaskAlpha(mask.y, 3, _MaskInteraction.y)
* GetMaskAlpha(mask.z, 7, _MaskInteraction.z)
* GetMaskAlpha(mask.w, 15, _MaskInteraction.w);
#if SOFTMASK_EDITOR
fixed isSceneView = max(Approximately(UNITY_MATRIX_V, _SceneView), Approximately(UNITY_MATRIX_P, _SceneProj));
alpha = lerp(alpha, 1, isSceneView);
#endif
return alpha;
}
#endif // UI_SOFTMASK_INCLUDED