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#ifndef WATER_LIGHTING_INCLUDED
#define WATER_LIGHTING_INCLUDED
#include "Packages/com.unity.render-pipelines.universal/ShaderLibrary/Lighting.hlsl"
half CalculateFresnelTerm(half3 normalWS, half3 viewDirectionWS)
{
return saturate(pow(1.0 - dot(normalWS, viewDirectionWS), 5));//fresnel TODO - find a better place
}
///////////////////////////////////////////////////////////////////////////////
// Lighting Calculations //
///////////////////////////////////////////////////////////////////////////////
//diffuse
half4 VertexLightingAndFog(half3 normalWS, half3 posWS, half3 clipPos)
{
half3 vertexLight = VertexLighting(posWS, normalWS);
half fogFactor = ComputeFogFactor(clipPos.z);
return half4(fogFactor, vertexLight);
}
//specular
half3 Highlights(half3 positionWS, half roughness, half3 normalWS, half3 viewDirectionWS)
{
Light mainLight = GetMainLight();
half roughness2 = roughness * roughness;
half3 halfDir = SafeNormalize(mainLight.direction + viewDirectionWS);
half NoH = saturate(dot(normalize(normalWS), halfDir));
half LoH = saturate(dot(mainLight.direction, halfDir));
// GGX Distribution multiplied by combined approximation of Visibility and Fresnel
// See "Optimizing PBR for Mobile" from Siggraph 2015 moving mobile graphics course
// https://community.arm.com/events/1155
half d = NoH * NoH * (roughness2 - 1.h) + 1.0001h;
half LoH2 = LoH * LoH;
half specularTerm = roughness2 / ((d * d) * max(0.1h, LoH2) * (roughness + 0.5h) * 4);
// on mobiles (where half actually means something) denominator have risk of overflow
// clamp below was added specifically to "fix" that, but dx compiler (we convert bytecode to metal/gles)
// sees that specularTerm have only non-negative terms, so it skips max(0,..) in clamp (leaving only min(100,...))
#if defined (SHADER_API_MOBILE)
specularTerm = specularTerm - HALF_MIN;
specularTerm = clamp(specularTerm, 0.0, 5.0); // Prevent FP16 overflow on mobiles
#endif
return specularTerm * mainLight.color * mainLight.distanceAttenuation;
}
//Soft Shadows
half SoftShadows(float3 screenUV, float3 positionWS)
{
half2 jitterUV = screenUV.xy * _ScreenParams.xy * _DitherPattern_TexelSize.xy;
half shadowAttenuation = 0;
uint loop = 4;
float loopDiv = 1.0 / loop;
for (uint i = 0u; i < loop; ++i)
{
#ifndef _STATIC_WATER
jitterUV += frac(half2(_Time.x, -_Time.z));
#endif
float3 jitterTexture = SAMPLE_TEXTURE2D(_DitherPattern, sampler_DitherPattern, jitterUV + i * _ScreenParams.xy).xyz * 2 - 1;
float3 lightJitter = positionWS + jitterTexture.xzy * 2;
shadowAttenuation += SAMPLE_TEXTURE2D_SHADOW(_MainLightShadowmapTexture, sampler_MainLightShadowmapTexture, TransformWorldToShadowCoord(lightJitter));
}
return BEYOND_SHADOW_FAR(TransformWorldToShadowCoord(positionWS * 1.1)) ? 1.0 : shadowAttenuation * loopDiv;
}
///////////////////////////////////////////////////////////////////////////////
// Reflection Modes //
///////////////////////////////////////////////////////////////////////////////
half3 SampleReflections(half3 normalWS, half3 viewDirectionWS, half2 screenUV, half roughness)
{
half3 reflection = 0;
half2 refOffset = 0;
#if _REFLECTION_CUBEMAP
half3 reflectVector = reflect(-viewDirectionWS, normalWS);
reflection = SAMPLE_TEXTURECUBE(_CubemapTexture, sampler_CubemapTexture, reflectVector).rgb;
#elif _REFLECTION_PROBES
half3 reflectVector = reflect(-viewDirectionWS, normalWS);
reflection = GlossyEnvironmentReflection(reflectVector, 0, 1);
#elif _REFLECTION_PLANARREFLECTION
// get the perspective projection
float2 p11_22 = float2(unity_CameraInvProjection._11, unity_CameraInvProjection._22) * 10;
// conver the uvs into view space by "undoing" projection
float3 viewDir = -(float3((screenUV * 2 - 1) / p11_22, -1));
half3 viewNormal = mul(normalWS, (float3x3)GetWorldToViewMatrix()).xyz;
half3 reflectVector = reflect(-viewDir, viewNormal);
half2 reflectionUV = screenUV + normalWS.zx * half2(0.02, 0.15);
reflection += SAMPLE_TEXTURE2D_LOD(_PlanarReflectionTexture, sampler_ScreenTextures_linear_clamp, reflectionUV, 6 * roughness).rgb;//planar reflection
#endif
//do backup
//return reflectVector.yyy;
return reflection;
}
#endif // WATER_LIGHTING_INCLUDED