Files
Convention-Unity-Demo/Assets/Samples/Universal RP/14.0.11/URP Package Samples/RendererFeatures/KeepFrame/KeepFrameFeature.cs

121 lines
4.5 KiB
C#

using System;
using UnityEngine;
using UnityEngine.Rendering;
using UnityEngine.Rendering.Universal;
//This renderer feature will replicate a "don't clear" behaviour by injecting two passes into the pipeline:
//One pass that copies color at the end of a frame
//Another pass that draws the content of the copied texture at the beginning of a new frame
public class KeepFrameFeature : ScriptableRendererFeature
{
//This pass is responsible for copying color to a specified destination
class CopyFramePass : ScriptableRenderPass
{
private RTHandle source { get; set; }
private RTHandle destination { get; set; }
public void Setup(RTHandle source, RTHandle destination)
{
this.source = source;
this.destination = destination;
}
public override void Execute(ScriptableRenderContext context, ref RenderingData renderingData)
{
if (renderingData.cameraData.camera.cameraType != CameraType.Game)
return;
CommandBuffer cmd = CommandBufferPool.Get("CopyFramePass");
Blit(cmd, source, destination);
context.ExecuteCommandBuffer(cmd);
CommandBufferPool.Release(cmd);
}
}
//This pass is responsible for drawing the old color to a full screen quad
class DrawOldFramePass : ScriptableRenderPass
{
private Material m_DrawOldFrameMaterial;
private RTHandle m_Handle;
private string m_TextureName;
public void Setup(Material drawOldFrameMaterial, RTHandle handle, string textureName)
{
m_DrawOldFrameMaterial = drawOldFrameMaterial;
m_TextureName = textureName;
m_Handle = handle;
}
public override void Execute(ScriptableRenderContext context, ref RenderingData renderingData)
{
if (m_DrawOldFrameMaterial != null)
{
CommandBuffer cmd = CommandBufferPool.Get("DrawOldFramePass");
cmd.SetGlobalTexture(m_TextureName, m_Handle);
var source = renderingData.cameraData.renderer.cameraColorTargetHandle;
Vector2 viewportScale = source.useScaling ? new Vector2(source.rtHandleProperties.rtHandleScale.x, source.rtHandleProperties.rtHandleScale.y) : Vector2.one;
Blitter.BlitTexture(cmd, source, viewportScale, m_DrawOldFrameMaterial, 0);
context.ExecuteCommandBuffer(cmd);
CommandBufferPool.Release(cmd);
}
}
}
[Serializable]
public class Settings
{
[Tooltip("The material that is used when the old frame is redrawn at the start of the new frame (before opaques).")]
public Material displayMaterial;
[Tooltip("The name of the texture used for referencing the copied frame. (Defaults to _FrameCopyTex if empty)")]
public string textureName;
}
private CopyFramePass m_CopyFrame;
private DrawOldFramePass m_DrawOldFrame;
private RTHandle m_OldFrameHandle;
public Settings settings = new Settings();
//In this function the passes are created and their point of injection is set
public override void Create()
{
m_CopyFrame = new CopyFramePass();
m_CopyFrame.renderPassEvent = RenderPassEvent.AfterRenderingTransparents; //Frame color is copied late in the frame
m_DrawOldFrame = new DrawOldFramePass();
m_DrawOldFrame.renderPassEvent = RenderPassEvent.BeforeRenderingOpaques; //Old frame is drawn early in the frame
}
public override void AddRenderPasses(ScriptableRenderer renderer, ref RenderingData renderingData)
{
renderer.EnqueuePass(m_CopyFrame);
renderer.EnqueuePass(m_DrawOldFrame);
}
public override void SetupRenderPasses(ScriptableRenderer renderer, in RenderingData renderingData)
{
var descriptor = renderingData.cameraData.cameraTargetDescriptor;
descriptor.msaaSamples = 1;
descriptor.depthBufferBits = 0;
var textureName = String.IsNullOrEmpty(settings.textureName) ? "_FrameCopyTex" : settings.textureName;
RenderingUtils.ReAllocateIfNeeded(ref m_OldFrameHandle, descriptor, FilterMode.Bilinear, TextureWrapMode.Clamp, name: textureName);
m_DrawOldFrame.ConfigureClear(ClearFlag.None, Color.red);
m_CopyFrame.Setup(renderer.cameraColorTargetHandle, m_OldFrameHandle);
m_DrawOldFrame.Setup(settings.displayMaterial, m_OldFrameHandle, textureName);
}
protected override void Dispose(bool disposing)
{
m_OldFrameHandle?.Release();
}
}