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
 
 
 
 

629 行
32 KiB

using System;
using System.Collections.Generic;
using UnityEngine.Rendering;
namespace UnityEngine.Experimental.Rendering.LightweightPipeline
{
[Serializable]
public class ShadowSettings
{
public LightShadows directionalShadowQuality;
public bool screenSpace;
public int directionalShadowAtlasWidth;
public int directionalShadowAtlasHeight;
public LightShadows localLightsShadowQuality;
public int localShadowAtlasWidth;
public int localShadowAtlasHeight;
public int bufferBitCount;
public float maxShadowDistance;
public int directionalLightCascadeCount;
public Vector3 directionalLightCascades;
public RenderTextureFormat shadowmapTextureFormat;
public RenderTextureFormat screenspaceShadowmapTextureFormat;
static ShadowSettings defaultShadowSettings = null;
public static ShadowSettings Default
{
get
{
if (defaultShadowSettings == null)
{
defaultShadowSettings = new ShadowSettings();
defaultShadowSettings.directionalShadowQuality = LightShadows.None;
defaultShadowSettings.screenSpace = true;
defaultShadowSettings.directionalShadowAtlasHeight = defaultShadowSettings.directionalShadowAtlasWidth = 2048;
defaultShadowSettings.localLightsShadowQuality = LightShadows.None;
defaultShadowSettings.localShadowAtlasWidth = 512;
defaultShadowSettings.localShadowAtlasHeight = 512;
defaultShadowSettings.bufferBitCount = 16;
defaultShadowSettings.directionalLightCascadeCount = 1;
defaultShadowSettings.directionalLightCascades = new Vector3(0.05F, 0.2F, 0.3F);
defaultShadowSettings.shadowmapTextureFormat = RenderTextureFormat.Shadowmap;
defaultShadowSettings.screenspaceShadowmapTextureFormat = RenderTextureFormat.R8;
}
return defaultShadowSettings;
}
}
}
public struct ShadowSliceData
{
public Matrix4x4 shadowTransform;
public int offsetX;
public int offsetY;
public int resolution;
public void Clear()
{
shadowTransform = Matrix4x4.identity;
offsetX = offsetY = 0;
resolution = 1024;
}
}
public class LightweightShadowPass
{
public bool IsDirectionalShadowsEnabled { get { return m_ShadowSettings.directionalShadowQuality != LightShadows.None; } }
public bool IsLocalShadowsEnabled { get { return m_ShadowSettings.localLightsShadowQuality != LightShadows.None; }}
public bool RequireScreenSpaceShadowmap { get { return IsDirectionalShadowsEnabled && m_ShadowSettings.screenSpace; } }
public bool HasDirectionalShadowmap { get { return m_DirectionalShadowmapQuality != LightShadows.None; } }
public bool HasLocalLightsShadowmap { get { return m_LocalShadowmapQuality != LightShadows.None; } }
public float RenderingDistance { get { return m_ShadowSettings.maxShadowDistance; } }
private const int kMaxCascades = 4;
private int m_ShadowCasterCascadesCount;
private int m_DirectionalShadowmapID;
private int m_LocalShadowmapID;
private int m_ScreenSpaceShadowmapID;
private ShadowSettings m_ShadowSettings = ShadowSettings.Default;
private Material m_ScreenSpaceShadowsMaterial;
private RenderTexture m_DirectionalShadowmapTexture;
private RenderTexture m_LocalShadowmapTexture;
private RenderTargetIdentifier m_ScreenSpaceShadowmapTexture;
private RenderTextureDescriptor m_DirectionalShadowmapDescriptor;
private RenderTextureDescriptor m_LocalShadowmapDescriptor;
private LightShadows m_DirectionalShadowmapQuality;
private LightShadows m_LocalShadowmapQuality;
private Matrix4x4[] m_DirectionalShadowMatrices;
private ShadowSliceData[] m_CascadeSlices;
private Vector4[] m_CascadeSplitDistances;
private Vector4 m_CascadeSplitRadii;
private Matrix4x4[] m_LocalShadowMatrices;
private ShadowSliceData[] m_LocalLightSlices;
private float[] m_LocalShadowStrength;
public LightweightShadowPass(LightweightPipelineAsset pipelineAsset, int maxLocalLightsCount)
{
BuildShadowSettings(pipelineAsset);
m_DirectionalShadowMatrices = new Matrix4x4[kMaxCascades + 1];
m_CascadeSlices = new ShadowSliceData[kMaxCascades];
m_CascadeSplitDistances = new Vector4[kMaxCascades];
m_LocalShadowMatrices = new Matrix4x4[maxLocalLightsCount];
m_LocalLightSlices = new ShadowSliceData[maxLocalLightsCount];
m_LocalShadowStrength = new float[maxLocalLightsCount];
DirectionalShadowConstantBuffer._WorldToShadow = Shader.PropertyToID("_WorldToShadow");
DirectionalShadowConstantBuffer._ShadowData = Shader.PropertyToID("_ShadowData");
DirectionalShadowConstantBuffer._DirShadowSplitSpheres = Shader.PropertyToID("_DirShadowSplitSpheres");
DirectionalShadowConstantBuffer._DirShadowSplitSphereRadii = Shader.PropertyToID("_DirShadowSplitSphereRadii");
DirectionalShadowConstantBuffer._ShadowOffset0 = Shader.PropertyToID("_ShadowOffset0");
DirectionalShadowConstantBuffer._ShadowOffset1 = Shader.PropertyToID("_ShadowOffset1");
DirectionalShadowConstantBuffer._ShadowOffset2 = Shader.PropertyToID("_ShadowOffset2");
DirectionalShadowConstantBuffer._ShadowOffset3 = Shader.PropertyToID("_ShadowOffset3");
DirectionalShadowConstantBuffer._ShadowmapSize = Shader.PropertyToID("_ShadowmapSize");
LocalShadowConstantBuffer._LocalWorldToShadowAtlas = Shader.PropertyToID("_LocalWorldToShadowAtlas");
LocalShadowConstantBuffer._LocalShadowStrength = Shader.PropertyToID("_LocalShadowStrength");
LocalShadowConstantBuffer._LocalShadowOffset0 = Shader.PropertyToID("_LocalShadowOffset0");
LocalShadowConstantBuffer._LocalShadowOffset1 = Shader.PropertyToID("_LocalShadowOffset1");
LocalShadowConstantBuffer._LocalShadowOffset2 = Shader.PropertyToID("_LocalShadowOffset2");
LocalShadowConstantBuffer._LocalShadowOffset3 = Shader.PropertyToID("_LocalShadowOffset3");
LocalShadowConstantBuffer._LocalShadowmapSize = Shader.PropertyToID("_LocalShadowmapSize");
m_DirectionalShadowmapID = Shader.PropertyToID("_ShadowMap");
m_LocalShadowmapID = Shader.PropertyToID("_LocalShadowMapAtlas");
m_ScreenSpaceShadowmapID = Shader.PropertyToID("_ScreenSpaceShadowMap");
m_ScreenSpaceShadowmapTexture = new RenderTargetIdentifier(m_ScreenSpaceShadowmapID);
m_DirectionalShadowmapDescriptor = new RenderTextureDescriptor(m_ShadowSettings.directionalShadowAtlasWidth,
m_ShadowSettings.directionalShadowAtlasHeight, m_ShadowSettings.shadowmapTextureFormat, m_ShadowSettings.bufferBitCount);
m_LocalShadowmapDescriptor = new RenderTextureDescriptor(m_ShadowSettings.localShadowAtlasWidth,
m_ShadowSettings.localShadowAtlasHeight, m_ShadowSettings.shadowmapTextureFormat, m_ShadowSettings.bufferBitCount);
m_ScreenSpaceShadowsMaterial = CoreUtils.CreateEngineMaterial(pipelineAsset.ScreenSpaceShadowShader);
Clear();
}
public void InitializeResources(CommandBuffer cmd, RenderTextureDescriptor renderTextureDesc)
{
if (RequireScreenSpaceShadowmap)
{
renderTextureDesc.depthBufferBits = 0;
renderTextureDesc.colorFormat = m_ShadowSettings.screenspaceShadowmapTextureFormat;
cmd.GetTemporaryRT(m_ScreenSpaceShadowmapID, renderTextureDesc, FilterMode.Bilinear);
}
}
public void Dispose(CommandBuffer cmd)
{
cmd.ReleaseTemporaryRT(m_ScreenSpaceShadowmapID);
if (m_DirectionalShadowmapTexture)
{
RenderTexture.ReleaseTemporary(m_DirectionalShadowmapTexture);
m_DirectionalShadowmapTexture = null;
}
if (m_LocalShadowmapTexture)
{
RenderTexture.ReleaseTemporary(m_LocalShadowmapTexture);
m_LocalShadowmapTexture = null;
}
}
public bool Execute(ref CullResults cullResults, ref LightData lightData, ref ScriptableRenderContext context)
{
Clear();
bool directionalShadowmapRendered = false;
if (IsDirectionalShadowsEnabled)
directionalShadowmapRendered = RenderDirectionalCascadeShadowmap(ref cullResults, ref lightData, ref context);
if (IsLocalShadowsEnabled)
RenderLocalShadowmapAtlas(ref cullResults, ref lightData, ref context);
return directionalShadowmapRendered && m_ShadowSettings.screenSpace;
}
public void CollectShadows(Camera camera, FrameRenderingConfiguration frameRenderingConfiguration, ref ScriptableRenderContext context)
{
CommandBuffer cmd = CommandBufferPool.Get("Collect Shadows");
SetShadowCollectPassKeywords(cmd);
// Note: The source isn't actually 'used', but there's an engine peculiarity (bug) that
// doesn't like null sources when trying to determine a stereo-ized blit. So for proper
// stereo functionality, we use the screen-space shadow map as the source (until we have
// a better solution).
// An alternative would be DrawProcedural, but that would require further changes in the shader.
cmd.Blit(m_ScreenSpaceShadowmapTexture, m_ScreenSpaceShadowmapTexture, m_ScreenSpaceShadowsMaterial);
LightweightUtils.StartStereoRendering(camera, ref context, frameRenderingConfiguration);
context.ExecuteCommandBuffer(cmd);
LightweightUtils.StopStereoRendering(camera, ref context, frameRenderingConfiguration);
CommandBufferPool.Release(cmd);
}
private void BuildShadowSettings(LightweightPipelineAsset pipelineAsset)
{
bool isOpenGLES2 = SystemInfo.graphicsDeviceType == GraphicsDeviceType.OpenGLES2;
bool supportsLocalShadows = Application.isMobilePlatform || Application.platform == RuntimePlatform.WebGLPlayer;
m_ShadowSettings = ShadowSettings.Default;
m_ShadowSettings.directionalShadowQuality = (LightShadows)pipelineAsset.ShadowSetting;
// Until we can have keyword stripping forcing single cascade hard shadows on gles2
m_ShadowSettings.screenSpace = !isOpenGLES2;
m_ShadowSettings.directionalLightCascadeCount = (isOpenGLES2) ? 1 : pipelineAsset.CascadeCount;
m_ShadowSettings.directionalShadowAtlasWidth = pipelineAsset.ShadowAtlasResolution;
m_ShadowSettings.directionalShadowAtlasHeight = pipelineAsset.ShadowAtlasResolution;
m_ShadowSettings.maxShadowDistance = pipelineAsset.ShadowDistance;
m_ShadowSettings.shadowmapTextureFormat = SystemInfo.SupportsRenderTextureFormat(RenderTextureFormat.Shadowmap)
? RenderTextureFormat.Shadowmap
: RenderTextureFormat.Depth;
m_ShadowSettings.screenspaceShadowmapTextureFormat = SystemInfo.SupportsRenderTextureFormat(RenderTextureFormat.R8)
? RenderTextureFormat.R8
: RenderTextureFormat.ARGB32;
switch (m_ShadowSettings.directionalLightCascadeCount)
{
case 1:
m_ShadowSettings.directionalLightCascades = new Vector3(1.0f, 0.0f, 0.0f);
break;
case 2:
m_ShadowSettings.directionalLightCascades = new Vector3(pipelineAsset.Cascade2Split, 1.0f, 0.0f);
break;
default:
m_ShadowSettings.directionalLightCascades = pipelineAsset.Cascade4Split;
break;
}
// Until we can have keyword stripping we disable local light shadows on mobile
m_ShadowSettings.localLightsShadowQuality = (supportsLocalShadows) ? LightShadows.Hard : LightShadows.None;
}
private void Clear()
{
m_DirectionalShadowmapTexture = null;
m_LocalShadowmapTexture = null;
m_DirectionalShadowmapQuality = LightShadows.None;
m_LocalShadowmapQuality = LightShadows.None;
for (int i = 0; i < m_DirectionalShadowMatrices.Length; ++i)
m_DirectionalShadowMatrices[i] = Matrix4x4.identity;
for (int i = 0; i < m_LocalShadowMatrices.Length; ++i)
m_LocalShadowMatrices[i] = Matrix4x4.identity;
for (int i = 0; i < m_CascadeSplitDistances.Length; ++i)
m_CascadeSplitDistances[i] = new Vector4(0.0f, 0.0f, 0.0f, 0.0f);
m_CascadeSplitRadii = new Vector4(0.0f, 0.0f, 0.0f, 0.0f);
for (int i = 0; i < m_CascadeSlices.Length; ++i)
m_CascadeSlices[i].Clear();
for (int i = 0; i < m_LocalLightSlices.Length; ++i)
m_LocalLightSlices[i].Clear();
for (int i = 0; i < m_LocalShadowStrength.Length; ++i)
m_LocalShadowStrength[i] = 0.0f;
}
private void SetShadowCollectPassKeywords(CommandBuffer cmd)
{
CoreUtils.SetKeyword(cmd, "_SHADOWS_SOFT", m_DirectionalShadowmapQuality == LightShadows.Soft);
CoreUtils.SetKeyword(cmd, "_SHADOWS_CASCADE", m_ShadowSettings.directionalLightCascadeCount > 1);
}
private bool RenderDirectionalCascadeShadowmap(ref CullResults cullResults, ref LightData lightData, ref ScriptableRenderContext context)
{
int shadowLightIndex = lightData.mainLightIndex;
if (shadowLightIndex == -1)
return false;
VisibleLight shadowLight = lightData.visibleLights[shadowLightIndex];
Light light = shadowLight.light;
Debug.Assert(shadowLight.lightType == LightType.Directional);
if (light.shadows == LightShadows.None)
return false;
CommandBuffer cmd = CommandBufferPool.Get("Prepare Directional Shadowmap");
m_ShadowCasterCascadesCount = m_ShadowSettings.directionalLightCascadeCount;
int shadowResolution = GetMaxTileResolutionInAtlas(m_ShadowSettings.directionalShadowAtlasWidth, m_ShadowSettings.directionalShadowAtlasHeight, m_ShadowCasterCascadesCount);
float shadowNearPlane = light.shadowNearPlane;
Bounds bounds;
if (!cullResults.GetShadowCasterBounds(shadowLightIndex, out bounds))
return false;
Matrix4x4 view, proj;
var settings = new DrawShadowsSettings(cullResults, shadowLightIndex);
m_DirectionalShadowmapTexture = RenderTexture.GetTemporary(m_DirectionalShadowmapDescriptor);
m_DirectionalShadowmapTexture.filterMode = FilterMode.Bilinear;
m_DirectionalShadowmapTexture.wrapMode = TextureWrapMode.Clamp;
CoreUtils.SetRenderTarget(cmd, m_DirectionalShadowmapTexture, ClearFlag.Depth);
bool success = false;
for (int cascadeIndex = 0; cascadeIndex < m_ShadowCasterCascadesCount; ++cascadeIndex)
{
success = cullResults.ComputeDirectionalShadowMatricesAndCullingPrimitives(shadowLightIndex,
cascadeIndex, m_ShadowCasterCascadesCount, m_ShadowSettings.directionalLightCascades, shadowResolution, shadowNearPlane, out view, out proj,
out settings.splitData);
float cullingSphereRadius = settings.splitData.cullingSphere.w;
m_CascadeSplitDistances[cascadeIndex] = settings.splitData.cullingSphere;
m_CascadeSplitRadii[cascadeIndex] = cullingSphereRadius * cullingSphereRadius;
if (!success)
break;
m_CascadeSlices[cascadeIndex].offsetX = (cascadeIndex % 2) * shadowResolution;
m_CascadeSlices[cascadeIndex].offsetY = (cascadeIndex / 2) * shadowResolution;
m_CascadeSlices[cascadeIndex].resolution = shadowResolution;
m_CascadeSlices[cascadeIndex].shadowTransform = GetShadowTransform(proj, view);
// If we have shadow cascades baked into the atlas we bake cascade transform
// in each shadow matrix to save shader ALU and L/S
if (m_ShadowCasterCascadesCount > 1)
ApplySliceTransform(ref m_CascadeSlices[cascadeIndex], m_ShadowSettings.directionalShadowAtlasWidth, m_ShadowSettings.directionalShadowAtlasHeight);
SetupShadowCasterConstants(cmd, ref shadowLight, proj, shadowResolution);
RenderShadowSlice(cmd, ref context, ref m_CascadeSlices[cascadeIndex], proj, view, settings);
}
if (success)
{
m_DirectionalShadowmapQuality = (m_ShadowSettings.directionalShadowQuality != LightShadows.Soft) ? LightShadows.Hard : light.shadows;
// In order to avoid shader variants explosion we only do hard shadows when sampling shadowmap in the lit pass.
// GLES2 platform is forced to hard single cascade shadows.
if (!m_ShadowSettings.screenSpace)
m_DirectionalShadowmapQuality = LightShadows.Hard;
SetupDirectionalShadowReceiverConstants(cmd, shadowLight, ref context);
}
context.ExecuteCommandBuffer(cmd);
CommandBufferPool.Release(cmd);
return success;
}
private void RenderLocalShadowmapAtlas(ref CullResults cullResults, ref LightData lightData, ref ScriptableRenderContext context)
{
List<int> localLightIndices = lightData.localLightIndices;
List<VisibleLight> visibleLights = lightData.visibleLights;
int shadowCastingLightsCount = 0;
int localLightsCount = localLightIndices.Count;
for (int i = 0; i < localLightsCount; ++i)
{
VisibleLight shadowLight = visibleLights[localLightIndices[i]];
if (shadowLight.lightType == LightType.Spot && shadowLight.light.shadows != LightShadows.None)
shadowCastingLightsCount++;
}
if (shadowCastingLightsCount == 0)
return;
CommandBuffer cmd = CommandBufferPool.Get("Prepare Local Lights Shadowmap");
Matrix4x4 view, proj;
Bounds bounds;
// TODO: Add support to point light shadows. We make a simplification here that only works
// for spot lights and with max spot shadows per pass.
int atlasWidth = m_ShadowSettings.localShadowAtlasWidth;
int atlasHeight = m_ShadowSettings.localShadowAtlasHeight;
int sliceResolution = GetMaxTileResolutionInAtlas(atlasWidth, atlasHeight, shadowCastingLightsCount);
int shadowSampling = 0;
m_LocalShadowmapTexture = RenderTexture.GetTemporary(m_LocalShadowmapDescriptor);
m_LocalShadowmapTexture.filterMode = FilterMode.Bilinear;
m_LocalShadowmapTexture.wrapMode = TextureWrapMode.Clamp;
CoreUtils.SetRenderTarget(cmd, m_LocalShadowmapTexture, ClearFlag.Depth);
for (int i = 0; i < localLightsCount; ++i)
{
int shadowLightIndex = localLightIndices[i];
VisibleLight shadowLight = visibleLights[shadowLightIndex];
Light light = shadowLight.light;
// TODO: Add support to point light shadows
if (shadowLight.lightType != LightType.Spot || shadowLight.light.shadows == LightShadows.None)
continue;
if (!cullResults.GetShadowCasterBounds(shadowLightIndex, out bounds))
continue;
var settings = new DrawShadowsSettings(cullResults, shadowLightIndex);
if (cullResults.ComputeSpotShadowMatricesAndCullingPrimitives(shadowLightIndex, out view, out proj, out settings.splitData))
{
// This way of computing the shadow slice only work for spots and with most 4 shadow casting lights per pass
// Change this when point lights are supported.
Debug.Assert(localLightsCount <= 4 && shadowLight.lightType == LightType.Spot);
// TODO: We need to pass bias and scale list to shader to be able to support multiple
// shadow casting local lights.
m_LocalLightSlices[i].offsetX = (i % 2) * sliceResolution;
m_LocalLightSlices[i].offsetY = (i / 2) * sliceResolution;
m_LocalLightSlices[i].resolution = sliceResolution;
m_LocalLightSlices[i].shadowTransform = GetShadowTransform(proj, view);
if (shadowCastingLightsCount > 1)
ApplySliceTransform(ref m_LocalLightSlices[i], atlasWidth, atlasHeight);
SetupShadowCasterConstants(cmd, ref shadowLight, proj, sliceResolution);
RenderShadowSlice(cmd, ref context, ref m_LocalLightSlices[i], proj, view, settings);
m_LocalShadowStrength[i] = light.shadowStrength;
shadowSampling = Math.Max(shadowSampling, (int)light.shadows);
}
}
SetupLocalLightsShadowReceiverConstants(cmd, ref context);
m_LocalShadowmapQuality = (LightShadows)Math.Min(shadowSampling, (int)m_ShadowSettings.directionalShadowQuality);
context.ExecuteCommandBuffer(cmd);
CommandBufferPool.Release(cmd);
}
private Matrix4x4 GetShadowTransform(Matrix4x4 proj, Matrix4x4 view)
{
// Currently CullResults ComputeDirectionalShadowMatricesAndCullingPrimitives doesn't
// apply z reversal to projection matrix. We need to do it manually here.
if (SystemInfo.usesReversedZBuffer)
{
proj.m20 = -proj.m20;
proj.m21 = -proj.m21;
proj.m22 = -proj.m22;
proj.m23 = -proj.m23;
}
Matrix4x4 worldToShadow = proj * view;
var textureScaleAndBias = Matrix4x4.identity;
textureScaleAndBias.m00 = 0.5f;
textureScaleAndBias.m11 = 0.5f;
textureScaleAndBias.m22 = 0.5f;
textureScaleAndBias.m03 = 0.5f;
textureScaleAndBias.m23 = 0.5f;
textureScaleAndBias.m13 = 0.5f;
// Apply texture scale and offset to save a MAD in shader.
return textureScaleAndBias * worldToShadow;
}
private void ApplySliceTransform(ref ShadowSliceData shadowSliceData, int atlasWidth, int atlasHeight)
{
Matrix4x4 sliceTransform = Matrix4x4.identity;
float oneOverAtlasWidth = 1.0f / atlasWidth;
float oneOverAtlasHeight = 1.0f / atlasHeight;
sliceTransform.m00 = shadowSliceData.resolution * oneOverAtlasWidth;
sliceTransform.m11 = shadowSliceData.resolution * oneOverAtlasHeight;
sliceTransform.m03 = shadowSliceData.offsetX * oneOverAtlasWidth;
sliceTransform.m13 = shadowSliceData.offsetY * oneOverAtlasHeight;
// Apply shadow slice scale and offset
shadowSliceData.shadowTransform = sliceTransform * shadowSliceData.shadowTransform;
}
private void RenderShadowSlice(CommandBuffer cmd, ref ScriptableRenderContext context, ref ShadowSliceData shadowSliceData,
Matrix4x4 proj, Matrix4x4 view, DrawShadowsSettings settings)
{
cmd.SetViewport(new Rect(shadowSliceData.offsetX, shadowSliceData.offsetY, shadowSliceData.resolution, shadowSliceData.resolution));
cmd.EnableScissorRect(new Rect(shadowSliceData.offsetX + 4, shadowSliceData.offsetY + 4, shadowSliceData.resolution - 8, shadowSliceData.resolution - 8));
cmd.SetViewProjectionMatrices(view, proj);
context.ExecuteCommandBuffer(cmd);
cmd.Clear();
context.DrawShadows(ref settings);
cmd.DisableScissorRect();
context.ExecuteCommandBuffer(cmd);
cmd.Clear();
}
private int GetMaxTileResolutionInAtlas(int atlasWidth, int atlasHeight, int tileCount)
{
int resolution = Mathf.Min(atlasWidth, atlasHeight);
if (tileCount > Mathf.Log(resolution))
{
Debug.LogError(
String.Format(
"Cannot fit {0} tiles into current shadowmap atlas of size ({1}, {2}). ShadowMap Resolution set to zero.",
tileCount, atlasWidth, atlasHeight));
return 0;
}
int currentTileCount = atlasWidth / resolution * atlasHeight / resolution;
while (currentTileCount < tileCount)
{
resolution = resolution >> 1;
currentTileCount = atlasWidth / resolution * atlasHeight / resolution;
}
return resolution;
}
private void SetupShadowCasterConstants(CommandBuffer cmd, ref VisibleLight visibleLight, Matrix4x4 proj, float cascadeResolution)
{
Light light = visibleLight.light;
float bias = 0.0f;
float normalBias = 0.0f;
// Use same kernel radius as built-in pipeline so we can achieve same bias results
// with the default light bias parameters.
const float kernelRadius = 3.65f;
if (visibleLight.lightType == LightType.Directional)
{
// Scale bias by cascade's world space depth range.
// Directional shadow lights have orthogonal projection.
// proj.m22 = -2 / (far - near) since the projection's depth range is [-1.0, 1.0]
// In order to be correct we should multiply bias by 0.5 but this introducing aliasing along cascades more visible.
float sign = (SystemInfo.usesReversedZBuffer) ? 1.0f : -1.0f;
bias = light.shadowBias * proj.m22 * sign;
// Currently only square POT cascades resolutions are used.
// We scale normalBias
double frustumWidth = 2.0 / (double)proj.m00;
double frustumHeight = 2.0 / (double)proj.m11;
float texelSizeX = (float)(frustumWidth / (double)cascadeResolution);
float texelSizeY = (float)(frustumHeight / (double)cascadeResolution);
float texelSize = Mathf.Max(texelSizeX, texelSizeY);
// Since we are applying normal bias on caster side we want an inset normal offset
// thus we use a negative normal bias.
normalBias = -light.shadowNormalBias * texelSize * kernelRadius;
}
else if (visibleLight.lightType == LightType.Spot)
{
float sign = (SystemInfo.usesReversedZBuffer) ? -1.0f : 1.0f;
bias = light.shadowBias * sign;
normalBias = 0.0f;
}
else
{
Debug.LogWarning("Only spot and directional shadow casters are supported in lightweight pipeline");
}
Vector3 lightDirection = -visibleLight.localToWorld.GetColumn(2);
cmd.SetGlobalVector("_ShadowBias", new Vector4(bias, normalBias, 0.0f, 0.0f));
cmd.SetGlobalVector("_LightDirection", new Vector4(lightDirection.x, lightDirection.y, lightDirection.z, 0.0f));
}
private void SetupDirectionalShadowReceiverConstants(CommandBuffer cmd, VisibleLight shadowLight, ref ScriptableRenderContext context)
{
Light light = shadowLight.light;
int cascadeCount = m_ShadowCasterCascadesCount;
for (int i = 0; i < kMaxCascades; ++i)
m_DirectionalShadowMatrices[i] = (cascadeCount >= i) ? m_CascadeSlices[i].shadowTransform : Matrix4x4.identity;
// We setup and additional a no-op WorldToShadow matrix in the last index
// because the ComputeCascadeIndex function in Shadows.hlsl can return an index
// out of bounds. (position not inside any cascade) and we want to avoid branching
Matrix4x4 noOpShadowMatrix = Matrix4x4.zero;
noOpShadowMatrix.m33 = (SystemInfo.usesReversedZBuffer) ? 1.0f : 0.0f;
m_DirectionalShadowMatrices[kMaxCascades] = noOpShadowMatrix;
float invShadowAtlasWidth = 1.0f / m_ShadowSettings.directionalShadowAtlasWidth;
float invShadowAtlasHeight = 1.0f / m_ShadowSettings.directionalShadowAtlasHeight;
float invHalfShadowAtlasWidth = 0.5f * invShadowAtlasWidth;
float invHalfShadowAtlasHeight = 0.5f * invShadowAtlasHeight;
cmd.SetGlobalTexture(m_DirectionalShadowmapID, m_DirectionalShadowmapTexture);
cmd.SetGlobalMatrixArray(DirectionalShadowConstantBuffer._WorldToShadow, m_DirectionalShadowMatrices);
cmd.SetGlobalVector(DirectionalShadowConstantBuffer._ShadowData, new Vector4(light.shadowStrength, 0.0f, 0.0f, 0.0f));
cmd.SetGlobalVectorArray(DirectionalShadowConstantBuffer._DirShadowSplitSpheres, m_CascadeSplitDistances);
cmd.SetGlobalVector(DirectionalShadowConstantBuffer._DirShadowSplitSphereRadii, m_CascadeSplitRadii);
cmd.SetGlobalVector(DirectionalShadowConstantBuffer._ShadowOffset0, new Vector4(-invHalfShadowAtlasWidth, -invHalfShadowAtlasHeight, 0.0f, 0.0f));
cmd.SetGlobalVector(DirectionalShadowConstantBuffer._ShadowOffset1, new Vector4(invHalfShadowAtlasWidth, -invHalfShadowAtlasHeight, 0.0f, 0.0f));
cmd.SetGlobalVector(DirectionalShadowConstantBuffer._ShadowOffset2, new Vector4(-invHalfShadowAtlasWidth, invHalfShadowAtlasHeight, 0.0f, 0.0f));
cmd.SetGlobalVector(DirectionalShadowConstantBuffer._ShadowOffset3, new Vector4(invHalfShadowAtlasWidth, invHalfShadowAtlasHeight, 0.0f, 0.0f));
cmd.SetGlobalVector(DirectionalShadowConstantBuffer._ShadowmapSize, new Vector4(invShadowAtlasWidth, invShadowAtlasHeight,
m_ShadowSettings.directionalShadowAtlasWidth, m_ShadowSettings.directionalShadowAtlasHeight));
context.ExecuteCommandBuffer(cmd);
cmd.Clear();
}
private void SetupLocalLightsShadowReceiverConstants(CommandBuffer cmd, ref ScriptableRenderContext context)
{
for (int i = 0; i < m_LocalLightSlices.Length; ++i)
m_LocalShadowMatrices[i] = m_LocalLightSlices[i].shadowTransform;
float invShadowAtlasWidth = 1.0f / m_ShadowSettings.localShadowAtlasWidth;
float invShadowAtlasHeight = 1.0f / m_ShadowSettings.localShadowAtlasHeight;
float invHalfShadowAtlasWidth = 0.5f * invShadowAtlasWidth;
float invHalfShadowAtlasHeight = 0.5f * invShadowAtlasHeight;
cmd.SetGlobalTexture(m_LocalShadowmapID, m_LocalShadowmapTexture);
cmd.SetGlobalMatrixArray(LocalShadowConstantBuffer._LocalWorldToShadowAtlas, m_LocalShadowMatrices);
cmd.SetGlobalFloatArray(LocalShadowConstantBuffer._LocalShadowStrength, m_LocalShadowStrength);
cmd.SetGlobalVector(LocalShadowConstantBuffer._LocalShadowOffset0, new Vector4(-invHalfShadowAtlasWidth, -invHalfShadowAtlasHeight, 0.0f, 0.0f));
cmd.SetGlobalVector(LocalShadowConstantBuffer._LocalShadowOffset1, new Vector4(invHalfShadowAtlasWidth, -invHalfShadowAtlasHeight, 0.0f, 0.0f));
cmd.SetGlobalVector(LocalShadowConstantBuffer._LocalShadowOffset2, new Vector4(-invHalfShadowAtlasWidth, invHalfShadowAtlasHeight, 0.0f, 0.0f));
cmd.SetGlobalVector(LocalShadowConstantBuffer._LocalShadowOffset3, new Vector4(invHalfShadowAtlasWidth, invHalfShadowAtlasHeight, 0.0f, 0.0f));
cmd.SetGlobalVector(LocalShadowConstantBuffer._LocalShadowmapSize, new Vector4(invShadowAtlasWidth, invShadowAtlasHeight,
m_ShadowSettings.localShadowAtlasWidth, m_ShadowSettings.localShadowAtlasHeight));
context.ExecuteCommandBuffer(cmd);
cmd.Clear();
}
};
}