301 lines
12 KiB
HLSL
301 lines
12 KiB
HLSL
|
|
#ifndef UNIVERSAL_REALTIME_LIGHTS_INCLUDED
|
|
#define UNIVERSAL_REALTIME_LIGHTS_INCLUDED
|
|
|
|
#include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/AmbientOcclusion.hlsl"
|
|
#include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Input.hlsl"
|
|
#include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Shadows.hlsl"
|
|
#include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/LightCookie/LightCookie.hlsl"
|
|
#include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Clustering.hlsl"
|
|
|
|
// Abstraction over Light shading data.
|
|
struct Light
|
|
{
|
|
half3 direction;
|
|
half3 color;
|
|
float distanceAttenuation; // full-float precision required on some platforms
|
|
half shadowAttenuation;
|
|
uint layerMask;
|
|
};
|
|
|
|
#if USE_FORWARD_PLUS && defined(LIGHTMAP_ON) && defined(LIGHTMAP_SHADOW_MIXING)
|
|
#define FORWARD_PLUS_SUBTRACTIVE_LIGHT_CHECK if (_AdditionalLightsColor[lightIndex].a > 0.0h) continue;
|
|
#else
|
|
#define FORWARD_PLUS_SUBTRACTIVE_LIGHT_CHECK
|
|
#endif
|
|
|
|
#if USE_FORWARD_PLUS
|
|
#define LIGHT_LOOP_BEGIN(lightCount) { \
|
|
uint lightIndex; \
|
|
ClusterIterator _urp_internal_clusterIterator = ClusterInit(inputData.normalizedScreenSpaceUV, inputData.positionWS, 0); \
|
|
[loop] while (ClusterNext(_urp_internal_clusterIterator, lightIndex)) { \
|
|
lightIndex += URP_FP_DIRECTIONAL_LIGHTS_COUNT; \
|
|
FORWARD_PLUS_SUBTRACTIVE_LIGHT_CHECK
|
|
#define LIGHT_LOOP_END } }
|
|
#else
|
|
#define LIGHT_LOOP_BEGIN(lightCount) \
|
|
for (uint lightIndex = 0u; lightIndex < lightCount; ++lightIndex) {
|
|
#define LIGHT_LOOP_END }
|
|
#endif
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
// Attenuation Functions /
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
|
|
// Matches Unity Vanilla HINT_NICE_QUALITY attenuation
|
|
// Attenuation smoothly decreases to light range.
|
|
float DistanceAttenuation(float distanceSqr, half2 distanceAttenuation)
|
|
{
|
|
// We use a shared distance attenuation for additional directional and puctual lights
|
|
// for directional lights attenuation will be 1
|
|
float lightAtten = rcp(distanceSqr);
|
|
float2 distanceAttenuationFloat = float2(distanceAttenuation);
|
|
|
|
// Use the smoothing factor also used in the Unity lightmapper.
|
|
half factor = half(distanceSqr * distanceAttenuationFloat.x);
|
|
half smoothFactor = saturate(half(1.0) - factor * factor);
|
|
smoothFactor = smoothFactor * smoothFactor;
|
|
|
|
return lightAtten * smoothFactor;
|
|
}
|
|
|
|
half AngleAttenuation(half3 spotDirection, half3 lightDirection, half2 spotAttenuation)
|
|
{
|
|
// Spot Attenuation with a linear falloff can be defined as
|
|
// (SdotL - cosOuterAngle) / (cosInnerAngle - cosOuterAngle)
|
|
// This can be rewritten as
|
|
// invAngleRange = 1.0 / (cosInnerAngle - cosOuterAngle)
|
|
// SdotL * invAngleRange + (-cosOuterAngle * invAngleRange)
|
|
// SdotL * spotAttenuation.x + spotAttenuation.y
|
|
|
|
// If we precompute the terms in a MAD instruction
|
|
half SdotL = dot(spotDirection, lightDirection);
|
|
half atten = saturate(SdotL * spotAttenuation.x + spotAttenuation.y);
|
|
return atten * atten;
|
|
}
|
|
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
// Light Abstraction //
|
|
///////////////////////////////////////////////////////////////////////////////
|
|
|
|
Light GetMainLight()
|
|
{
|
|
Light light;
|
|
light.direction = half3(_MainLightPosition.xyz);
|
|
#if USE_FORWARD_PLUS
|
|
#if defined(LIGHTMAP_ON) && defined(LIGHTMAP_SHADOW_MIXING)
|
|
light.distanceAttenuation = _MainLightColor.a;
|
|
#else
|
|
light.distanceAttenuation = 1.0;
|
|
#endif
|
|
#else
|
|
light.distanceAttenuation = unity_LightData.z; // unity_LightData.z is 1 when not culled by the culling mask, otherwise 0.
|
|
#endif
|
|
light.shadowAttenuation = 1.0;
|
|
light.color = _MainLightColor.rgb;
|
|
|
|
light.layerMask = _MainLightLayerMask;
|
|
|
|
return light;
|
|
}
|
|
|
|
Light GetMainLight(float4 shadowCoord)
|
|
{
|
|
Light light = GetMainLight();
|
|
light.shadowAttenuation = MainLightRealtimeShadow(shadowCoord);
|
|
return light;
|
|
}
|
|
|
|
Light GetMainLight(float4 shadowCoord, float3 positionWS, half4 shadowMask)
|
|
{
|
|
Light light = GetMainLight();
|
|
light.shadowAttenuation = MainLightShadow(shadowCoord, positionWS, shadowMask, _MainLightOcclusionProbes);
|
|
|
|
#if defined(_LIGHT_COOKIES)
|
|
real3 cookieColor = SampleMainLightCookie(positionWS);
|
|
light.color *= cookieColor;
|
|
#endif
|
|
|
|
return light;
|
|
}
|
|
|
|
Light GetMainLight(InputData inputData, half4 shadowMask, AmbientOcclusionFactor aoFactor)
|
|
{
|
|
Light light = GetMainLight(inputData.shadowCoord, inputData.positionWS, shadowMask);
|
|
|
|
#if defined(_SCREEN_SPACE_OCCLUSION) && !defined(_SURFACE_TYPE_TRANSPARENT)
|
|
if (IsLightingFeatureEnabled(DEBUGLIGHTINGFEATUREFLAGS_AMBIENT_OCCLUSION))
|
|
{
|
|
light.color *= aoFactor.directAmbientOcclusion;
|
|
}
|
|
#endif
|
|
|
|
return light;
|
|
}
|
|
|
|
// Fills a light struct given a perObjectLightIndex
|
|
Light GetAdditionalPerObjectLight(int perObjectLightIndex, float3 positionWS)
|
|
{
|
|
// Abstraction over Light input constants
|
|
#if USE_STRUCTURED_BUFFER_FOR_LIGHT_DATA
|
|
float4 lightPositionWS = _AdditionalLightsBuffer[perObjectLightIndex].position;
|
|
half3 color = _AdditionalLightsBuffer[perObjectLightIndex].color.rgb;
|
|
half4 distanceAndSpotAttenuation = _AdditionalLightsBuffer[perObjectLightIndex].attenuation;
|
|
half4 spotDirection = _AdditionalLightsBuffer[perObjectLightIndex].spotDirection;
|
|
uint lightLayerMask = _AdditionalLightsBuffer[perObjectLightIndex].layerMask;
|
|
#else
|
|
float4 lightPositionWS = _AdditionalLightsPosition[perObjectLightIndex];
|
|
half3 color = _AdditionalLightsColor[perObjectLightIndex].rgb;
|
|
half4 distanceAndSpotAttenuation = _AdditionalLightsAttenuation[perObjectLightIndex];
|
|
half4 spotDirection = _AdditionalLightsSpotDir[perObjectLightIndex];
|
|
uint lightLayerMask = asuint(_AdditionalLightsLayerMasks[perObjectLightIndex]);
|
|
#endif
|
|
|
|
// Directional lights store direction in lightPosition.xyz and have .w set to 0.0.
|
|
// This way the following code will work for both directional and punctual lights.
|
|
float3 lightVector = lightPositionWS.xyz - positionWS * lightPositionWS.w;
|
|
float distanceSqr = max(dot(lightVector, lightVector), HALF_MIN);
|
|
|
|
half3 lightDirection = half3(lightVector * rsqrt(distanceSqr));
|
|
// full-float precision required on some platforms
|
|
float attenuation = DistanceAttenuation(distanceSqr, distanceAndSpotAttenuation.xy) * AngleAttenuation(spotDirection.xyz, lightDirection, distanceAndSpotAttenuation.zw);
|
|
|
|
Light light;
|
|
light.direction = lightDirection;
|
|
light.distanceAttenuation = attenuation;
|
|
light.shadowAttenuation = 1.0; // This value can later be overridden in GetAdditionalLight(uint i, float3 positionWS, half4 shadowMask)
|
|
light.color = color;
|
|
light.layerMask = lightLayerMask;
|
|
|
|
return light;
|
|
}
|
|
|
|
uint GetPerObjectLightIndexOffset()
|
|
{
|
|
#if USE_STRUCTURED_BUFFER_FOR_LIGHT_DATA
|
|
return uint(unity_LightData.x);
|
|
#else
|
|
return 0;
|
|
#endif
|
|
}
|
|
|
|
// Returns a per-object index given a loop index.
|
|
// This abstract the underlying data implementation for storing lights/light indices
|
|
int GetPerObjectLightIndex(uint index)
|
|
{
|
|
/////////////////////////////////////////////////////////////////////////////////////////////
|
|
// Structured Buffer Path /
|
|
// /
|
|
// Lights and light indices are stored in StructuredBuffer. We can just index them. /
|
|
// Currently all non-mobile platforms take this path :( /
|
|
// There are limitation in mobile GPUs to use SSBO (performance / no vertex shader support) /
|
|
/////////////////////////////////////////////////////////////////////////////////////////////
|
|
#if USE_STRUCTURED_BUFFER_FOR_LIGHT_DATA
|
|
uint offset = uint(unity_LightData.x);
|
|
return _AdditionalLightsIndices[offset + index];
|
|
|
|
/////////////////////////////////////////////////////////////////////////////////////////////
|
|
// UBO path /
|
|
// /
|
|
// We store 8 light indices in half4 unity_LightIndices[2]; /
|
|
// Due to memory alignment unity doesn't support int[] or float[] /
|
|
// Even trying to reinterpret cast the unity_LightIndices to float[] won't work /
|
|
// it will cast to float4[] and create extra register pressure. :( /
|
|
/////////////////////////////////////////////////////////////////////////////////////////////
|
|
#else
|
|
// since index is uint shader compiler will implement
|
|
// div & mod as bitfield ops (shift and mask).
|
|
|
|
// TODO: Can we index a float4? Currently compiler is
|
|
// replacing unity_LightIndicesX[i] with a dp4 with identity matrix.
|
|
// u_xlat16_40 = dot(unity_LightIndices[int(u_xlatu13)], ImmCB_0_0_0[u_xlati1]);
|
|
// This increases both arithmetic and register pressure.
|
|
//
|
|
// NOTE: min16float4 bug workaround.
|
|
// Take the "vec4" part into float4 tmp variable in order to force float4 math.
|
|
// It appears indexing half4 as min16float4 on DX11 can fail. (dp4 {min16f})
|
|
float4 tmp = unity_LightIndices[index / 4];
|
|
return int(tmp[index % 4]);
|
|
#endif
|
|
}
|
|
|
|
// Fills a light struct given a loop i index. This will convert the i
|
|
// index to a perObjectLightIndex
|
|
Light GetAdditionalLight(uint i, float3 positionWS)
|
|
{
|
|
#if USE_FORWARD_PLUS
|
|
int lightIndex = i;
|
|
#else
|
|
int lightIndex = GetPerObjectLightIndex(i);
|
|
#endif
|
|
return GetAdditionalPerObjectLight(lightIndex, positionWS);
|
|
}
|
|
|
|
Light GetAdditionalLight(uint i, float3 positionWS, half4 shadowMask)
|
|
{
|
|
#if USE_FORWARD_PLUS
|
|
int lightIndex = i;
|
|
#else
|
|
int lightIndex = GetPerObjectLightIndex(i);
|
|
#endif
|
|
Light light = GetAdditionalPerObjectLight(lightIndex, positionWS);
|
|
|
|
#if USE_STRUCTURED_BUFFER_FOR_LIGHT_DATA
|
|
half4 occlusionProbeChannels = _AdditionalLightsBuffer[lightIndex].occlusionProbeChannels;
|
|
#else
|
|
half4 occlusionProbeChannels = _AdditionalLightsOcclusionProbes[lightIndex];
|
|
#endif
|
|
light.shadowAttenuation = AdditionalLightShadow(lightIndex, positionWS, light.direction, shadowMask, occlusionProbeChannels);
|
|
#if defined(_LIGHT_COOKIES)
|
|
real3 cookieColor = SampleAdditionalLightCookie(lightIndex, positionWS);
|
|
light.color *= cookieColor;
|
|
#endif
|
|
|
|
return light;
|
|
}
|
|
|
|
Light GetAdditionalLight(uint i, InputData inputData, half4 shadowMask, AmbientOcclusionFactor aoFactor)
|
|
{
|
|
Light light = GetAdditionalLight(i, inputData.positionWS, shadowMask);
|
|
|
|
#if defined(_SCREEN_SPACE_OCCLUSION) && !defined(_SURFACE_TYPE_TRANSPARENT)
|
|
if (IsLightingFeatureEnabled(DEBUGLIGHTINGFEATUREFLAGS_AMBIENT_OCCLUSION))
|
|
{
|
|
light.color *= aoFactor.directAmbientOcclusion;
|
|
}
|
|
#endif
|
|
|
|
return light;
|
|
}
|
|
|
|
int GetAdditionalLightsCount()
|
|
{
|
|
#if USE_FORWARD_PLUS
|
|
// Counting the number of lights in clustered requires traversing the bit list, and is not needed up front.
|
|
return 0;
|
|
#else
|
|
// TODO: we need to expose in SRP api an ability for the pipeline cap the amount of lights
|
|
// in the culling. This way we could do the loop branch with an uniform
|
|
// This would be helpful to support baking exceeding lights in SH as well
|
|
return int(min(_AdditionalLightsCount.x, unity_LightData.y));
|
|
#endif
|
|
}
|
|
|
|
half4 CalculateShadowMask(InputData inputData)
|
|
{
|
|
// To ensure backward compatibility we have to avoid using shadowMask input, as it is not present in older shaders
|
|
#if defined(SHADOWS_SHADOWMASK) && defined(LIGHTMAP_ON)
|
|
half4 shadowMask = inputData.shadowMask; // Shadowmask was sampled from lightmap
|
|
#elif !defined(LIGHTMAP_ON) && (defined(PROBE_VOLUMES_L1) || defined(PROBE_VOLUMES_L2))
|
|
half4 shadowMask = inputData.shadowMask; // Shadowmask (probe occlusion) was sampled from APV
|
|
#elif !defined (LIGHTMAP_ON)
|
|
half4 shadowMask = unity_ProbesOcclusion; // Sample shadowmask (probe occlusion) from legacy probes
|
|
#else
|
|
half4 shadowMask = half4(1, 1, 1, 1); // Fallback shadowmask, fully unoccluded
|
|
#endif
|
|
|
|
return shadowMask;
|
|
}
|
|
|
|
#endif
|