修改水

Packages/com.waveharmonic.crest/Runtime/Shaders/Surface/Refraction.hlsl

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+// Crest Water System
+// Copyright © 2024 Wave Harmonic. All rights reserved.
+
+#ifndef CREST_WATER_REFRACTION_H
+#define CREST_WATER_REFRACTION_H
+
+#include "Packages/com.waveharmonic.crest/Runtime/Shaders/Library/Settings.Crest.hlsl"
+#include "Packages/com.waveharmonic.crest/Runtime/Shaders/Library/Macros.hlsl"
+#include "Packages/com.waveharmonic.crest/Runtime/Shaders/Library/Utility/Depth.hlsl"
+
+#if (CREST_PORTALS != 0)
+#include "Packages/com.waveharmonic.crest.portals/Runtime/Shaders/Library/Portals.hlsl"
+#endif
+
+#include "Packages/com.waveharmonic.crest/Runtime/Shaders/Surface/Utility.hlsl"
+
+#ifndef SUPPORTS_FOVEATED_RENDERING_NON_UNIFORM_RASTER
+#define FoveatedRemapLinearToNonUniform(uv) uv
+#endif
+
+m_CrestNameSpace
+
+// We take the unrefracted scene colour as input because having a Scene Colour node in the graph
+// appears to be necessary to ensure the scene colours are bound?
+void RefractedScene
+(
+    const half i_RefractionStrength,
+    const half3 i_NormalWS,
+    const float2 i_PositionNDC,
+    const float i_PixelZ,
+    const half3 i_SceneColorUnrefracted,
+    const float i_SceneZ,
+    const float i_SceneZRaw,
+    const bool i_Underwater,
+    out half3 o_SceneColor,
+    out float o_SceneDistance,
+    out float3 o_ScenePositionWS,
+    out bool o_Caustics
+)
+{
+    float2 positionNDC = i_PositionNDC;
+    float sceneDepthRaw = i_SceneZRaw;
+
+    o_Caustics = true;
+
+    // View ray intersects geometry surface either above or below water surface.
+    float2 refractOffset = i_RefractionStrength * i_NormalWS.xz;
+    if (!i_Underwater)
+    {
+        // We're above the water, so behind interface is depth fog.
+        refractOffset *= min(1.0, 0.5 * (i_SceneZ - i_PixelZ)) / i_SceneZ;
+    }
+    else
+    {
+        // When looking up through water, full strength ends up being quite intense so reduce it a bunch.
+        refractOffset *= 0.3;
+    }
+
+    // Blend at the edge of the screen to avoid artifacts.
+    refractOffset *= 1.0 - EdgeBlendingFactor(positionNDC, i_PixelZ);
+
+    const float2 positionNDCRefracted = FoveatedRemapLinearToNonUniform(positionNDC + refractOffset);
+    float sceneDepthRawRefracted = SHADERGRAPH_SAMPLE_SCENE_DEPTH(positionNDCRefracted);
+
+#if (CREST_PORTALS != 0)
+#if _ALPHATEST_ON
+    // Portals
+    ApplyPortalRefractions(positionNDCRefracted, i_SceneZRaw, i_Underwater, sceneDepthRawRefracted, o_Caustics);
+#endif
+#endif
+
+
+    const float sceneZRefract = Utility::CrestLinearEyeDepth(sceneDepthRawRefracted);
+
+    // Depth fog & caustics - only if view ray starts from above water.
+    // Compute depth fog alpha based on refracted position if it landed on an
+    // underwater surface, or on unrefracted depth otherwise.
+    if (sceneZRefract > i_PixelZ)
+    {
+        // Refracted.
+        o_SceneDistance = sceneZRefract - i_PixelZ;
+        o_SceneColor = SHADERGRAPH_SAMPLE_SCENE_COLOR(positionNDCRefracted);
+
+        positionNDC = positionNDCRefracted;
+        sceneDepthRaw = sceneDepthRawRefracted;
+    }
+    else
+    {
+        // Unrefracted.
+        // It seems that when MSAA is enabled this can sometimes be negative.
+        o_SceneDistance = max(i_SceneZ - i_PixelZ, 0.0);
+        o_SceneColor = i_SceneColorUnrefracted;
+
+        // NOTE: Causes refraction artifact with caustics. Cannot remember exactly why this was added.
+        // o_Caustics = false;
+        positionNDC = FoveatedRemapLinearToNonUniform(positionNDC);
+    }
+
+    if (i_Underwater)
+    {
+        // Depth fog is handled by underwater shader.
+        o_SceneDistance = i_PixelZ;
+    }
+
+    o_ScenePositionWS = ComputeWorldSpacePosition(positionNDC, sceneDepthRaw, UNITY_MATRIX_I_VP);
+#if (SHADEROPTIONS_CAMERA_RELATIVE_RENDERING != 0)
+    o_ScenePositionWS += _WorldSpaceCameraPos;
+#endif
+}
+
+m_CrestNameSpaceEnd
+
+#endif