您最多选择25个主题
主题必须以中文或者字母或数字开头，可以包含连字符 (-)，并且长度不得超过35个字符
178 行
8.6 KiB
178 行
8.6 KiB
#ifndef LIGHTWEIGHT_SHADOWS_INCLUDED
|
|
#define LIGHTWEIGHT_SHADOWS_INCLUDED
|
|
|
|
#include "CoreRP/ShaderLibrary/Common.hlsl"
|
|
#include "CoreRP/ShaderLibrary/Shadow/ShadowSamplingTent.hlsl"
|
|
#include "Core.hlsl"
|
|
|
|
#define MAX_SHADOW_CASCADES 4
|
|
|
|
#ifdef SHADER_API_GLES
|
|
#define SHADOWS_SCREEN 0
|
|
#else
|
|
#define SHADOWS_SCREEN 1
|
|
#endif
|
|
|
|
SCREENSPACE_TEXTURE(_ScreenSpaceShadowMap);
|
|
SAMPLER(sampler_ScreenSpaceShadowMap);
|
|
|
|
TEXTURE2D_SHADOW(_ShadowMap);
|
|
SAMPLER_CMP(sampler_ShadowMap);
|
|
|
|
CBUFFER_START(_ShadowBuffer)
|
|
// Last cascade is initialized with a no-op matrix. It always transforms
|
|
// shadow coord to half(0, 0, NEAR_PLANE). We use this trick to avoid
|
|
// branching since ComputeCascadeIndex can return cascade index = MAX_SHADOW_CASCADES
|
|
float4x4 _WorldToShadow[MAX_SHADOW_CASCADES + 1];
|
|
float4 _DirShadowSplitSpheres[MAX_SHADOW_CASCADES];
|
|
float4 _DirShadowSplitSphereRadii;
|
|
half4 _ShadowOffset0;
|
|
half4 _ShadowOffset1;
|
|
half4 _ShadowOffset2;
|
|
half4 _ShadowOffset3;
|
|
half4 _ShadowData; // (x: shadowStrength)
|
|
float4 _ShadowmapSize; // (xy: 1/width and 1/height, zw: width and height)
|
|
CBUFFER_END
|
|
|
|
#if UNITY_REVERSED_Z
|
|
#define BEYOND_SHADOW_FAR(shadowCoord) shadowCoord.z <= UNITY_RAW_FAR_CLIP_VALUE
|
|
#else
|
|
#define BEYOND_SHADOW_FAR(shadowCoord) shadowCoord.z >= UNITY_RAW_FAR_CLIP_VALUE
|
|
#endif
|
|
|
|
half GetShadowStrength()
|
|
{
|
|
return _ShadowData.x;
|
|
}
|
|
|
|
inline half SampleScreenSpaceShadowMap(float4 shadowCoord)
|
|
{
|
|
shadowCoord.xy /= shadowCoord.w;
|
|
|
|
// The stereo transform has to happen after the manual perspective divide
|
|
shadowCoord.xy = UnityStereoTransformScreenSpaceTex(shadowCoord.xy);
|
|
|
|
#if defined(UNITY_STEREO_INSTANCING_ENABLED) || defined(UNITY_STEREO_MULTIVIEW_ENABLED)
|
|
half attenuation = SAMPLE_TEXTURE2D_ARRAY(_ScreenSpaceShadowMap, sampler_ScreenSpaceShadowMap, shadowCoord.xy, unity_StereoEyeIndex).x;
|
|
#else
|
|
half attenuation = SAMPLE_TEXTURE2D(_ScreenSpaceShadowMap, sampler_ScreenSpaceShadowMap, shadowCoord.xy).x;
|
|
#endif
|
|
|
|
return attenuation;
|
|
}
|
|
|
|
inline real SampleShadowmap(float4 shadowCoord)
|
|
{
|
|
shadowCoord.xyz /= shadowCoord.w;
|
|
|
|
real attenuation;
|
|
|
|
#ifdef _SHADOWS_SOFT
|
|
#ifdef SHADER_API_MOBILE
|
|
// 4-tap hardware comparison
|
|
real4 attenuation4;
|
|
attenuation4.x = SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, shadowCoord.xyz + _ShadowOffset0.xyz);
|
|
attenuation4.y = SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, shadowCoord.xyz + _ShadowOffset1.xyz);
|
|
attenuation4.z = SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, shadowCoord.xyz + _ShadowOffset2.xyz);
|
|
attenuation4.w = SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, shadowCoord.xyz + _ShadowOffset3.xyz);
|
|
attenuation = dot(attenuation4, 0.25);
|
|
#else
|
|
#ifdef _SHADOWS_CASCADE //Assume screen space shadows when cascades enabled
|
|
float fetchesWeights[16];
|
|
float2 fetchesUV[16];
|
|
SampleShadow_ComputeSamples_Tent_7x7(_ShadowmapSize, shadowCoord.xy, fetchesWeights, fetchesUV);
|
|
|
|
attenuation = fetchesWeights[0] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[0].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[1] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[1].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[2] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[2].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[3] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[3].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[4] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[4].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[5] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[5].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[6] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[6].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[7] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[7].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[8] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[8].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[9] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[9].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[10] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[10].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[11] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[11].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[12] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[12].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[13] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[13].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[14] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[14].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[15] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[15].xy, shadowCoord.z));
|
|
#else
|
|
float fetchesWeights[9];
|
|
float2 fetchesUV[9];
|
|
SampleShadow_ComputeSamples_Tent_5x5(_ShadowmapSize, shadowCoord.xy, fetchesWeights, fetchesUV);
|
|
|
|
attenuation = fetchesWeights[0] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[0].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[1] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[1].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[2] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[2].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[3] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[3].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[4] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[4].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[5] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[5].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[6] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[6].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[7] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[7].xy, shadowCoord.z));
|
|
attenuation += fetchesWeights[8] * SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, float3(fetchesUV[8].xy, shadowCoord.z));
|
|
#endif
|
|
#endif
|
|
#else
|
|
// 1-tap hardware comparison
|
|
attenuation = SAMPLE_TEXTURE2D_SHADOW(_ShadowMap, sampler_ShadowMap, shadowCoord.xyz);
|
|
#endif
|
|
|
|
#if SHADER_HINT_NICE_QUALITY
|
|
// Apply shadow strength
|
|
attenuation = LerpWhiteTo(attenuation, GetShadowStrength());
|
|
#endif
|
|
|
|
// Shadow coords that fall out of the light frustum volume must always return attenuation 1.0
|
|
return BEYOND_SHADOW_FAR(shadowCoord) ? 1.0 : attenuation;
|
|
}
|
|
|
|
inline half ComputeCascadeIndex(float3 positionWS)
|
|
{
|
|
// TODO: profile if there's a performance improvement if we avoid indexing here
|
|
float3 fromCenter0 = positionWS.xyz - _DirShadowSplitSpheres[0].xyz;
|
|
float3 fromCenter1 = positionWS.xyz - _DirShadowSplitSpheres[1].xyz;
|
|
float3 fromCenter2 = positionWS.xyz - _DirShadowSplitSpheres[2].xyz;
|
|
float3 fromCenter3 = positionWS.xyz - _DirShadowSplitSpheres[3].xyz;
|
|
float4 distances2 = float4(dot(fromCenter0, fromCenter0), dot(fromCenter1, fromCenter1), dot(fromCenter2, fromCenter2), dot(fromCenter3, fromCenter3));
|
|
|
|
half4 weights = half4(distances2 < _DirShadowSplitSphereRadii);
|
|
weights.yzw = saturate(weights.yzw - weights.xyz);
|
|
|
|
return 4 - dot(weights, half4(4, 3, 2, 1));
|
|
}
|
|
|
|
float4 TransformWorldToShadowCoord(float3 positionWS)
|
|
{
|
|
#ifdef _SHADOWS_CASCADE
|
|
half cascadeIndex = ComputeCascadeIndex(positionWS);
|
|
return mul(_WorldToShadow[cascadeIndex], float4(positionWS, 1.0));
|
|
#else
|
|
return mul(_WorldToShadow[0], float4(positionWS, 1.0));
|
|
#endif
|
|
}
|
|
|
|
float4 ComputeShadowCoord(float4 clipPos)
|
|
{
|
|
// TODO: This might have to be corrected for double-wide and texture arrays
|
|
return ComputeScreenPos(clipPos);
|
|
}
|
|
|
|
half RealtimeShadowAttenuation(float4 shadowCoord)
|
|
{
|
|
#ifndef _SHADOWS_ENABLED
|
|
return 1.0h;
|
|
#endif
|
|
|
|
#if defined(NO_SHADOWS)
|
|
return 1.0h;
|
|
#elif SHADOWS_SCREEN
|
|
return SampleScreenSpaceShadowMap(shadowCoord);
|
|
#else
|
|
|
|
return SampleShadowmap(shadowCoord);
|
|
#endif
|
|
}
|
|
|
|
#endif
|