VolumetricLighting/Assets/VolumetricFog/Scripts/FogLight.DirectionalShadow.cs
2016-11-01 13:25:56 +01:00

158 lines
5.0 KiB
C#

using UnityEngine;
using UnityEngine.Rendering;
public partial class FogLight : LightOverride
{
CommandBuffer m_BufGrabShadowmap;
CommandBuffer m_BufGrabShadowParams;
RenderTexture m_Shadowmap;
ComputeBuffer m_ShadowParamsCB;
//[HideInInspector]
public Shader m_BlurShadowmapShader;
Material m_BlurShadowmapMaterial;
public Shader m_CopyShadowParamsShader;
Material m_CopyShadowParamsMaterial;
bool directionalShadow {get{ return m_Shadows && type == Type.Directional; }}
void InitDirectionalShadowmap()
{
if (m_BufGrabShadowmap != null || !directionalShadow)
return;
Light light = GetComponent<Light>();
m_BufGrabShadowmap = new CommandBuffer();
m_BufGrabShadowmap.name = "Grab shadowmap for Volumetric Fog";
light.AddCommandBuffer(LightEvent.AfterShadowMap, m_BufGrabShadowmap);
m_BufGrabShadowParams = new CommandBuffer();
m_BufGrabShadowParams.name = "Grab shadow params for Volumetric Fog";
light.AddCommandBuffer(LightEvent.BeforeScreenspaceMask, m_BufGrabShadowParams);
m_BlurShadowmapMaterial = new Material(m_BlurShadowmapShader);
m_BlurShadowmapMaterial.hideFlags = HideFlags.HideAndDontSave;
m_CopyShadowParamsMaterial = new Material(m_CopyShadowParamsShader);
m_CopyShadowParamsMaterial.hideFlags = HideFlags.HideAndDontSave;
}
int[] temp;
public void UpdateDirectionalShadowmap()
{
InitDirectionalShadowmap();
if (m_BufGrabShadowmap != null)
m_BufGrabShadowmap.Clear();
if (m_BufGrabShadowParams != null)
m_BufGrabShadowParams.Clear();
if (!directionalShadow)
return;
// Copy directional shadowmap params - they're only set for regular shaders, but we need them in compute
if (m_ShadowParamsCB == null)
m_ShadowParamsCB = new ComputeBuffer(1, 336);
Graphics.SetRandomWriteTarget(2, m_ShadowParamsCB);
m_BufGrabShadowParams.DrawProcedural(Matrix4x4.identity, m_CopyShadowParamsMaterial, 0, MeshTopology.Points, 1);
// TODO: get the real size of the shadowmap
int startRes = 4096;
// To make things easier, blurred shadowmap is at most half the size of the regular.
int targetRes = Mathf.Min((int)m_ShadowmapRes, startRes/2);
int downsampleSteps = (int)Mathf.Log(startRes / targetRes, 2);
RenderTargetIdentifier shadowmap = BuiltinRenderTextureType.CurrentActive;
m_BufGrabShadowmap.SetShadowSamplingMode(shadowmap, ShadowSamplingMode.RawDepth);
// RFloat for ESM, RGHalf for VSM
RenderTextureFormat format = RenderTextureFormat.RGHalf;
ReleaseTemporary(ref m_Shadowmap);
m_Shadowmap = RenderTexture.GetTemporary(targetRes, targetRes, 0, format, RenderTextureReadWrite.Linear);
m_Shadowmap.filterMode = FilterMode.Bilinear;
m_Shadowmap.wrapMode = TextureWrapMode.Clamp;
if (temp == null || temp.Length != downsampleSteps - 1)
temp = new int[downsampleSteps - 1];
for (int i = 0, currentRes = startRes/2; i < downsampleSteps; i++)
{
m_BufGrabShadowmap.SetGlobalVector("_TexelSize", new Vector4(0.5f/currentRes, 0.5f/currentRes, 0, 0));
RenderTargetIdentifier targetRT;
if (i < downsampleSteps - 1)
{
temp[i] = Shader.PropertyToID("ShadowmapDownscaleTemp" + i);
m_BufGrabShadowmap.GetTemporaryRT(temp[i], currentRes, currentRes, 0, FilterMode.Bilinear, format, RenderTextureReadWrite.Linear);
targetRT = new RenderTargetIdentifier(temp[i]);
}
else
{
// Last step: write into the shadowmap texture
targetRT = new RenderTargetIdentifier(m_Shadowmap);
}
if (i == 0)
{
// This step should convert to ESM/VSM
// m_BufGrabShadowmap.Blit(shadowmap, targetRT);
m_BufGrabShadowmap.SetGlobalTexture("_DirShadowmap", shadowmap);
m_BufGrabShadowmap.Blit(null, targetRT, m_BlurShadowmapMaterial, /*sample & convert to VSM*/ 4);
}
else
{
m_BufGrabShadowmap.Blit(temp[i - 1], targetRT, m_BlurShadowmapMaterial, /*regular sample*/ 5);
}
currentRes /= 2;
}
//var directionalShadowmapBlurred = Shader.PropertyToID("_DirectionalShadowmapBlurred");
//m_BufGrabShadowmap.GetTemporaryRT(directionalShadowmapBlurred, 1024, 1024, 0, FilterMode.Bilinear, RenderTextureFormat.RFloat, RenderTextureReadWrite.Linear);
//m_BufGrabShadowmap.Blit(shadowmap, m_Shadowmap);
//m_BufGrabShadowmap.SetGlobalTexture(directionalShadowmapBlurred, directionalShadowmapBlurred);
}
void CleanupDirectionalShadowmap()
{
if (m_BufGrabShadowmap != null)
m_BufGrabShadowmap.Clear();
if (m_BufGrabShadowParams != null)
m_BufGrabShadowParams.Clear();
if(m_ShadowParamsCB != null)
m_ShadowParamsCB.Release();
m_ShadowParamsCB = null;
}
public bool SetUpDirectionalShadowmapForSampling(bool shadows, ComputeShader cs, int kernel)
{
if (!shadows || m_ShadowParamsCB == null || m_Shadowmap == null)
{
cs.SetFloat("_DirLightShadows", 0);
return false;
}
cs.SetFloat("_DirLightShadows", 1);
cs.SetBuffer(kernel, "_ShadowParams", m_ShadowParamsCB);
cs.SetTexture(kernel, "_DirectionalShadowmap", m_Shadowmap);
return true;
}
void ReleaseTemporary(ref RenderTexture rt)
{
if (rt == null)
return;
RenderTexture.ReleaseTemporary(rt);
rt = null;
}
}