static internal void ReinitializeVolumetricBufferParams(HDCamera hdCamera)
{
if (!Fog.IsVolumetricFogEnabled(hdCamera))
{
return;
}
bool fog = Fog.IsVolumetricFogEnabled(hdCamera);
bool init = hdCamera.vBufferParams != null;
if (fog ^ init)
{
if (init)
{
// Deinitialize.
hdCamera.vBufferParams = null;
}
else
{
// Initialize.
// Start with the same parameters for both frames. Then update them one by one every frame.
var parameters = ComputeVolumetricBufferParameters(hdCamera);
hdCamera.vBufferParams = new VBufferParameters[2];
hdCamera.vBufferParams[0] = parameters;
hdCamera.vBufferParams[1] = parameters;
}
}
}
// This function relies on being called once per camera per frame.
// The results are undefined otherwise.
static internal void UpdateVolumetricBufferParams(HDCamera hdCamera)
{
if (!Fog.IsVolumetricFogEnabled(hdCamera))
{
return;
}
Debug.Assert(hdCamera.vBufferParams != null);
Debug.Assert(hdCamera.vBufferParams.Length == 2);
var currentParams = ComputeVolumetricBufferParameters(hdCamera);
int frameIndex = (int)VolumetricFrameIndex(hdCamera);
var currIdx = (frameIndex + 0) & 1;
var prevIdx = (frameIndex + 1) & 1;
hdCamera.vBufferParams[currIdx] = currentParams;
// Handle case of first frame. When we are on the first frame, we reuse the value of original frame.
if (hdCamera.vBufferParams[prevIdx].viewportSize.x == 0.0f && hdCamera.vBufferParams[prevIdx].viewportSize.y == 0.0f)
{
hdCamera.vBufferParams[prevIdx] = currentParams;
}
// Update size used to create volumetric buffers.
s_CurrentVolumetricBufferSize = new Vector3Int(Math.Max(s_CurrentVolumetricBufferSize.x, currentParams.viewportSize.x),
Math.Max(s_CurrentVolumetricBufferSize.y, currentParams.viewportSize.y),
Math.Max(s_CurrentVolumetricBufferSize.z, currentParams.viewportSize.z));
}
void UpdateShaderVariablesGlobalVolumetrics(ref ShaderVariablesGlobal cb, HDCamera hdCamera)
{
if (!Fog.IsVolumetricFogEnabled(hdCamera))
{
return;
}
// Get the interpolated anisotropy value.
var fog = hdCamera.volumeStack.GetComponent <Fog>();
int frameIndex = m_FrameCount;
int currIdx = (frameIndex + 0) & 1;
var currParams = hdCamera.vBufferParams[currIdx];
// The lighting & density buffers are shared by all cameras.
// The history & feedback buffers are specific to the camera.
// These 2 types of buffers can have different sizes.
// Additionally, history buffers can have different sizes, since they are not resized at the same time.
var cvp = currParams.viewportSize;
// Adjust slices for XR rendering: VBuffer is shared for all single-pass views
uint sliceCount = (uint)(cvp.z / hdCamera.viewCount);
cb._VBufferViewportSize = new Vector4(cvp.x, cvp.y, 1.0f / cvp.x, 1.0f / cvp.y);
cb._VBufferSliceCount = sliceCount;
cb._VBufferRcpSliceCount = 1.0f / sliceCount;
cb._VBufferLightingViewportScale = currParams.ComputeViewportScale(m_CurrentVolumetricBufferSize);
cb._VBufferLightingViewportLimit = currParams.ComputeViewportLimit(m_CurrentVolumetricBufferSize);
cb._VBufferDistanceEncodingParams = currParams.depthEncodingParams;
cb._VBufferDistanceDecodingParams = currParams.depthDecodingParams;
cb._VBufferLastSliceDist = currParams.ComputeLastSliceDistance(sliceCount);
cb._VBufferRcpInstancedViewCount = 1.0f / hdCamera.viewCount;
}
// Must be called AFTER UpdateVolumetricBufferParams.
internal void ResizeVolumetricLightingBuffers(HDCamera hdCamera, int frameIndex)
{
if (!Fog.IsVolumetricFogEnabled(hdCamera))
{
return;
}
Debug.Assert(hdCamera.vBufferParams != null);
// Render texture contents can become "lost" on certain events, like loading a new level,
// system going to a screensaver mode, in and out of fullscreen and so on.
// https://docs.unity3d.com/ScriptReference/RenderTexture.html
if (m_DensityBuffer == null || m_LightingBuffer == null)
{
DestroyVolumetricLightingBuffers();
CreateVolumetricLightingBuffers();
}
var currIdx = (frameIndex + 0) & 1;
var prevIdx = (frameIndex + 1) & 1;
var currentParams = hdCamera.vBufferParams[currIdx];
ResizeVolumetricBuffer(ref m_DensityBuffer, "VBufferDensity", currentParams.viewportSize.x,
currentParams.viewportSize.y,
currentParams.viewportSize.z);
ResizeVolumetricBuffer(ref m_LightingBuffer, "VBufferLighting", currentParams.viewportSize.x,
currentParams.viewportSize.y,
currentParams.viewportSize.z);
// TODO RENDERGRAPH: For now those texture are not handled by render graph.
// When they are we won't have the m_DensityBuffer handy for getting the current size in UpdateShaderVariablesGlobalVolumetrics
// So we store the size here and in time we'll fill this vector differently.
m_CurrentVolumetricBufferSize = new Vector3Int(m_DensityBuffer.rt.width, m_DensityBuffer.rt.height, m_DensityBuffer.rt.volumeDepth);
}
// Must be called AFTER UpdateVolumetricBufferParams.
internal void ResizeVolumetricLightingBuffers(HDCamera hdCamera, int frameIndex)
{
if (!Fog.IsVolumetricFogEnabled(hdCamera))
{
return;
}
Debug.Assert(hdCamera.vBufferParams != null);
// Render texture contents can become "lost" on certain events, like loading a new level,
// system going to a screensaver mode, in and out of fullscreen and so on.
// https://docs.unity3d.com/ScriptReference/RenderTexture.html
if (m_DensityBuffer == null || m_LightingBuffer == null)
{
DestroyVolumetricLightingBuffers();
CreateVolumetricLightingBuffers();
}
var currIdx = (frameIndex + 0) & 1;
var prevIdx = (frameIndex + 1) & 1;
var currentParams = hdCamera.vBufferParams[currIdx];
ResizeVolumetricBuffer(ref m_DensityBuffer, "VBufferDensity", currentParams.viewportSize.x,
currentParams.viewportSize.y,
currentParams.viewportSize.z);
ResizeVolumetricBuffer(ref m_LightingBuffer, "VBufferLighting", currentParams.viewportSize.x,
currentParams.viewportSize.y,
currentParams.viewportSize.z);
}
DensityVolumeList PrepareVisibleDensityVolumeList(HDCamera hdCamera, CommandBuffer cmd, float time)
{
DensityVolumeList densityVolumes = new DensityVolumeList();
if (!Fog.IsVolumetricFogEnabled(hdCamera))
{
return(densityVolumes);
}
using (new ProfilingScope(cmd, ProfilingSampler.Get(HDProfileId.PrepareVisibleDensityVolumeList)))
{
Vector3 camPosition = hdCamera.camera.transform.position;
Vector3 camOffset = Vector3.zero;// World-origin-relative
if (ShaderConfig.s_CameraRelativeRendering != 0)
{
camOffset = camPosition; // Camera-relative
}
m_VisibleVolumeBounds.Clear();
m_VisibleVolumeData.Clear();
// Collect all visible finite volume data, and upload it to the GPU.
var volumes = DensityVolumeManager.manager.PrepareDensityVolumeData(cmd, hdCamera, time);
for (int i = 0; i < Math.Min(volumes.Count, k_MaxVisibleVolumeCount); i++)
{
DensityVolume volume = volumes[i];
// TODO: cache these?
var obb = new OrientedBBox(Matrix4x4.TRS(volume.transform.position, volume.transform.rotation, volume.parameters.size));
// Handle camera-relative rendering.
obb.center -= camOffset;
// Frustum cull on the CPU for now. TODO: do it on the GPU.
// TODO: account for custom near and far planes of the V-Buffer's frustum.
// It's typically much shorter (along the Z axis) than the camera's frustum.
if (GeometryUtils.Overlap(obb, hdCamera.frustum, 6, 8))
{
// TODO: cache these?
var data = volume.parameters.ConvertToEngineData();
m_VisibleVolumeBounds.Add(obb);
m_VisibleVolumeData.Add(data);
}
}
m_VisibleVolumeBoundsBuffer.SetData(m_VisibleVolumeBounds);
m_VisibleVolumeDataBuffer.SetData(m_VisibleVolumeData);
// Fill the struct with pointers in order to share the data with the light loop.
densityVolumes.bounds = m_VisibleVolumeBounds;
densityVolumes.density = m_VisibleVolumeData;
return(densityVolumes);
}
}
// This function relies on being called once per camera per frame.
// The results are undefined otherwise.
internal void UpdateVolumetricBufferParams(HDCamera hdCamera)
{
if (!Fog.IsVolumetricFogEnabled(hdCamera))
{
return;
}
var parameters = ComputeVBufferParameters(hdCamera);
// Double-buffer. I assume the cost of copying is negligible (don't want to use the frame index).
// Handle case of first frame. When we are on the first frame, we reuse the value of original frame.
if (hdCamera.vBufferParams[0].viewportSize.x == 0.0f && hdCamera.vBufferParams[0].viewportSize.y == 0.0f)
{
hdCamera.vBufferParams[1] = parameters;
}
else
{
hdCamera.vBufferParams[1] = hdCamera.vBufferParams[0];
}
hdCamera.vBufferParams[0] = parameters;
}
// This function relies on being called once per camera per frame.
// The results are undefined otherwise.
static internal void UpdateVolumetricBufferParams(HDCamera hdCamera, int frameIndex)
{
if (!Fog.IsVolumetricFogEnabled(hdCamera))
{
return;
}
Debug.Assert(hdCamera.vBufferParams != null);
Debug.Assert(hdCamera.vBufferParams.Length == 2);
var currentParams = ComputeVolumetricBufferParameters(hdCamera);
var currIdx = (frameIndex + 0) & 1;
var prevIdx = (frameIndex + 1) & 1;
hdCamera.vBufferParams[currIdx] = currentParams;
// Handle case of first frame. When we are on the first frame, we reuse the value of original frame.
if (hdCamera.vBufferParams[prevIdx].viewportSize.x == 0.0f && hdCamera.vBufferParams[prevIdx].viewportSize.y == 0.0f)
{
hdCamera.vBufferParams[prevIdx] = currentParams;
}
}
static internal void CreateVolumetricHistoryBuffers(HDCamera hdCamera, int bufferCount)
{
if (!Fog.IsVolumetricFogEnabled(hdCamera))
{
return;
}
Debug.Assert(hdCamera.volumetricHistoryBuffers == null);
hdCamera.volumetricHistoryBuffers = new RTHandle[bufferCount];
// Allocation happens early in the frame. So we shouldn't rely on 'hdCamera.vBufferParams'.
// Allocate the smallest possible 3D texture.
// We will perform rescaling manually, in a custom manner, based on volume parameters.
const int minSize = 4;
for (int i = 0; i < bufferCount; i++)
{
hdCamera.volumetricHistoryBuffers[i] = RTHandles.Alloc(minSize, minSize, minSize, colorFormat: GraphicsFormat.R16G16B16A16_SFloat, // 8888_sRGB is not precise enough
dimension: TextureDimension.Tex3D, enableRandomWrite: true, name: string.Format("VBufferHistory{0}", i));
}
hdCamera.volumetricHistoryIsValid = false;
}
void PushVolumetricLightingGlobalParams(HDCamera hdCamera, CommandBuffer cmd, int frameIndex)
{
if (!Fog.IsVolumetricFogEnabled(hdCamera))
{
cmd.SetGlobalTexture(HDShaderIDs._VBufferLighting, HDUtils.clearTexture3D);
return;
}
// Get the interpolated anisotropy value.
var fog = hdCamera.volumeStack.GetComponent <Fog>();
SetPreconvolvedAmbientLightProbe(hdCamera, cmd, fog.globalLightProbeDimmer.value, fog.anisotropy.value);
var currFrameParams = hdCamera.vBufferParams[0];
var prevFrameParams = hdCamera.vBufferParams[1];
// The lighting & density buffers are shared by all cameras.
// The history & feedback buffers are specific to the camera.
// These 2 types of buffers can have different sizes.
// Additionally, history buffers can have different sizes, since they are not resized at the same time
// (every frame, we swap the buffers, and resize the feedback buffer but not the history buffer).
// The viewport size is the same for all of these buffers.
// All of these buffers may have sub-native-resolution viewports.
// The 3rd dimension (number of slices) is the same for all of these buffers.
Vector2Int sharedBufferSize = new Vector2Int(m_LightingBufferHandle.rt.width, m_LightingBufferHandle.rt.height);
Debug.Assert(m_LightingBufferHandle.rt.width == m_DensityBufferHandle.rt.width);
Debug.Assert(m_LightingBufferHandle.rt.height == m_DensityBufferHandle.rt.height);
Vector2Int historyBufferSize = Vector2Int.zero;
if (hdCamera.IsVolumetricReprojectionEnabled())
{
var historyRT = hdCamera.GetPreviousFrameRT((int)HDCameraFrameHistoryType.VolumetricLighting);
historyBufferSize = new Vector2Int(historyRT.rt.width, historyRT.rt.height);
// Handle case of first frame. When we are on the first frame, we reuse the value of original frame.
if (historyBufferSize.x == 0.0f && historyBufferSize.y == 0.0f)
{
historyBufferSize = sharedBufferSize;
}
}
var cvp = currFrameParams.viewportSize;
var pvp = prevFrameParams.viewportSize;
// Adjust slices for XR rendering: VBuffer is shared for all single-pass views
int sliceCount = cvp.z / hdCamera.viewCount;
cmd.SetGlobalVector(HDShaderIDs._VBufferViewportSize, new Vector4(cvp.x, cvp.y, 1.0f / cvp.x, 1.0f / cvp.y));
cmd.SetGlobalInt(HDShaderIDs._VBufferSliceCount, sliceCount);
cmd.SetGlobalFloat(HDShaderIDs._VBufferRcpSliceCount, 1.0f / sliceCount);
cmd.SetGlobalVector(HDShaderIDs._VBufferSharedUvScaleAndLimit, currFrameParams.ComputeUvScaleAndLimit(sharedBufferSize));
cmd.SetGlobalVector(HDShaderIDs._VBufferDistanceEncodingParams, currFrameParams.depthEncodingParams);
cmd.SetGlobalVector(HDShaderIDs._VBufferDistanceDecodingParams, currFrameParams.depthDecodingParams);
cmd.SetGlobalFloat(HDShaderIDs._VBufferLastSliceDist, currFrameParams.ComputeLastSliceDistance(sliceCount));
cmd.SetGlobalFloat(HDShaderIDs._VBufferRcpInstancedViewCount, 1.0f / hdCamera.viewCount);
cmd.SetGlobalVector(HDShaderIDs._VBufferPrevViewportSize, new Vector4(pvp.x, pvp.y, 1.0f / pvp.x, 1.0f / pvp.y));
cmd.SetGlobalVector(HDShaderIDs._VBufferHistoryPrevUvScaleAndLimit, prevFrameParams.ComputeUvScaleAndLimit(historyBufferSize));
cmd.SetGlobalVector(HDShaderIDs._VBufferPrevDepthEncodingParams, prevFrameParams.depthEncodingParams);
cmd.SetGlobalVector(HDShaderIDs._VBufferPrevDepthDecodingParams, prevFrameParams.depthDecodingParams);
cmd.SetGlobalTexture(HDShaderIDs._VBufferLighting, m_LightingBufferHandle);
}
