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
 
 
 
 

168 行
8.0 KiB

// This files include various function uses to evaluate material
//-----------------------------------------------------------------------------
// Lighting structure for light accumulation
//-----------------------------------------------------------------------------
// These structure allow to accumulate lighting accross the Lit material
// AggregateLighting is init to zero and transfer to EvaluateBSDF, but the LightLoop can't access its content.
struct DirectLighting
{
float3 diffuse;
float3 specular;
};
struct IndirectLighting
{
float3 specularReflected;
float3 specularTransmitted;
};
struct AggregateLighting
{
DirectLighting direct;
IndirectLighting indirect;
};
void AccumulateDirectLighting(DirectLighting src, inout AggregateLighting dst)
{
dst.direct.diffuse += src.diffuse;
dst.direct.specular += src.specular;
}
void AccumulateIndirectLighting(IndirectLighting src, inout AggregateLighting dst)
{
dst.indirect.specularReflected += src.specularReflected;
dst.indirect.specularTransmitted += src.specularTransmitted;
}
//-----------------------------------------------------------------------------
// Ambient occlusion helper
//-----------------------------------------------------------------------------
// Ambient occlusion
struct AmbientOcclusionFactor
{
float3 indirectAmbientOcclusion;
float3 directAmbientOcclusion;
float3 indirectSpecularOcclusion;
};
void GetScreenSpaceAmbientOcclusion(float2 positionSS, float NdotV, float perceptualRoughness, float ambientOcclusionFromData, float specularOcclusionFromData, out AmbientOcclusionFactor aoFactor)
{
// Note: When we ImageLoad outside of texture size, the value returned by Load is 0 (Note: On Metal maybe it clamp to value of texture which is also fine)
// We use this property to have a neutral value for AO that doesn't consume a sampler and work also with compute shader (i.e use ImageLoad)
// We store inverse AO so neutral is black. So either we sample inside or outside the texture it return 0 in case of neutral
// Ambient occlusion use for indirect lighting (reflection probe, baked diffuse lighting)
#ifndef _SURFACE_TYPE_TRANSPARENT
float indirectAmbientOcclusion = 1.0 - LOAD_TEXTURE2D(_AmbientOcclusionTexture, positionSS).x;
// Ambient occlusion use for direct lighting (directional, punctual, area)
float directAmbientOcclusion = lerp(1.0, indirectAmbientOcclusion, _AmbientOcclusionParam.w);
#else
float indirectAmbientOcclusion = 1.0;
float directAmbientOcclusion = 1.0;
#endif
float roughness = PerceptualRoughnessToRoughness(perceptualRoughness);
float specularOcclusion = GetSpecularOcclusionFromAmbientOcclusion(ClampNdotV(NdotV), indirectAmbientOcclusion, roughness);
aoFactor.indirectSpecularOcclusion = lerp(_AmbientOcclusionParam.rgb, float3(1.0, 1.0, 1.0), min(specularOcclusionFromData, specularOcclusion));
aoFactor.indirectAmbientOcclusion = lerp(_AmbientOcclusionParam.rgb, float3(1.0, 1.0, 1.0), min(ambientOcclusionFromData, indirectAmbientOcclusion));
aoFactor.directAmbientOcclusion = lerp(_AmbientOcclusionParam.rgb, float3(1.0, 1.0, 1.0), directAmbientOcclusion);
}
void GetScreenSpaceAmbientOcclusionMultibounce(float2 positionSS, float NdotV, float perceptualRoughness, float ambientOcclusionFromData, float specularOcclusionFromData, float3 diffuseColor, float3 fresnel0, out AmbientOcclusionFactor aoFactor)
{
// Use GTAOMultiBounce approximation for ambient occlusion (allow to get a tint from the diffuseColor)
// Note: When we ImageLoad outside of texture size, the value returned by Load is 0 (Note: On Metal maybe it clamp to value of texture which is also fine)
// We use this property to have a neutral value for AO that doesn't consume a sampler and work also with compute shader (i.e use ImageLoad)
// We store inverse AO so neutral is black. So either we sample inside or outside the texture it return 0 in case of neutral
// Ambient occlusion use for indirect lighting (reflection probe, baked diffuse lighting)
#ifndef _SURFACE_TYPE_TRANSPARENT
float indirectAmbientOcclusion = 1.0 - LOAD_TEXTURE2D(_AmbientOcclusionTexture, positionSS).x;
// Ambient occlusion use for direct lighting (directional, punctual, area)
float directAmbientOcclusion = lerp(1.0, indirectAmbientOcclusion, _AmbientOcclusionParam.w);
#else
float indirectAmbientOcclusion = 1.0;
float directAmbientOcclusion = 1.0;
#endif
float roughness = PerceptualRoughnessToRoughness(perceptualRoughness);
float specularOcclusion = GetSpecularOcclusionFromAmbientOcclusion(ClampNdotV(NdotV), indirectAmbientOcclusion, roughness);
aoFactor.indirectSpecularOcclusion = GTAOMultiBounce(min(specularOcclusionFromData, specularOcclusion), fresnel0);
aoFactor.indirectAmbientOcclusion = GTAOMultiBounce(min(ambientOcclusionFromData, indirectAmbientOcclusion), diffuseColor);
aoFactor.directAmbientOcclusion = GTAOMultiBounce(directAmbientOcclusion, diffuseColor);
}
void ApplyAmbientOcclusionFactor(AmbientOcclusionFactor aoFactor, inout BuiltinData builtinData, inout AggregateLighting lighting)
{
// Note: in case of deferred Lit, builtinData.bakeDiffuseLighting contain indirect diffuse + emissive,
// so Ambient occlusion is multiply by emissive which is wrong but not a big deal
builtinData.bakeDiffuseLighting *= aoFactor.indirectAmbientOcclusion;
lighting.indirect.specularReflected *= aoFactor.indirectSpecularOcclusion;
lighting.direct.diffuse *= aoFactor.directAmbientOcclusion;
}
#ifdef DEBUG_DISPLAY
// mipmapColor is color use to store texture streaming information in XXXData.hlsl (look for DEBUGMIPMAPMODE_NONE)
void PostEvaluateBSDFDebugDisplay( AmbientOcclusionFactor aoFactor, BuiltinData builtinData, AggregateLighting lighting, float3 mipmapColor,
inout float3 diffuseLighting, inout float3 specularLighting)
{
if (_DebugLightingMode != 0)
{
// Caution: _DebugLightingMode is used in other part of the code, don't do anything outside of
// current cases
switch (_DebugLightingMode)
{
case DEBUGLIGHTINGMODE_LUX_METER:
diffuseLighting = lighting.direct.diffuse + builtinData.bakeDiffuseLighting;
//Compress lighting values for color picker if enabled
if (_ColorPickerMode != COLORPICKERDEBUGMODE_NONE)
diffuseLighting = diffuseLighting / LUXMETER_COMPRESSION_RATIO;
specularLighting = float3(0.0, 0.0, 0.0); // Disable specular lighting
break;
case DEBUGLIGHTINGMODE_INDIRECT_DIFFUSE_OCCLUSION:
diffuseLighting = aoFactor.indirectAmbientOcclusion;
specularLighting = float3(0.0, 0.0, 0.0); // Disable specular lighting
break;
case DEBUGLIGHTINGMODE_INDIRECT_SPECULAR_OCCLUSION:
diffuseLighting = aoFactor.indirectSpecularOcclusion;
specularLighting = float3(0.0, 0.0, 0.0); // Disable specular lighting
break;
case DEBUGLIGHTINGMODE_SCREEN_SPACE_TRACING_REFRACTION:
if (_DebugLightingSubMode != DEBUGSCREENSPACETRACING_COLOR)
diffuseLighting = lighting.indirect.specularTransmitted;
break;
case DEBUGLIGHTINGMODE_SCREEN_SPACE_TRACING_REFLECTION:
if (_DebugLightingSubMode != DEBUGSCREENSPACETRACING_COLOR)
diffuseLighting = lighting.indirect.specularReflected;
break;
case DEBUGLIGHTINGMODE_VISUALIZE_SHADOW_MASKS:
#ifdef SHADOWS_SHADOWMASK
diffuseLighting = float3(
builtinData.shadowMask0 / 2 + builtinData.shadowMask1 / 2,
builtinData.shadowMask1 / 2 + builtinData.shadowMask2 / 2,
builtinData.shadowMask2 / 2 + builtinData.shadowMask3 / 2
);
specularLighting = float3(0, 0, 0);
#endif
break ;
}
}
else if (_DebugMipMapMode != DEBUGMIPMAPMODE_NONE)
{
diffuseLighting = mipmapColor;
specularLighting = float3(0.0, 0.0, 0.0); // Disable specular lighting
}
}
#endif