Solved the problem that when VRTK transmission under Unity HDRP, the screen fades in and out, and the visual occlusion cannot be displayed correctly when passing through the wall

Unity HDRP下VRTK传送、穿墙 When the screen fades in and out、Visual occlusion does not display correctly problem solved

Unity HDRPThe rendering method and normalUnity有所不同,而SteamVRresponsible for the pluginVRFade in、Fade out script“SteamVR_Fade”is via a method that is executed after the camera has rendered a frameOnPostRender调用GL.QUADSTo perform drawing a slice,然后使用ShaderControls the color of this slice、Gradient, etc. to achieve the screen fade in、Fade out the function of obscuring the line of sight;

然而在HDRP中在OnPostRender下的GLDrawing does not display properly,要把“SteamVR_Fade”The script was originally placed in the normal way OnRenderObject 方法中调用GLThe part to be drawn is placed
UnityEngine.Rendering.RenderPipelineManager.endFrameRendering This method is called back.

	protected void OnCameraRender(ScriptableRenderContext context, Camera[] cameraList)
	{
    
		foreach (var camera in cameraList)
		{
    
			
				DrawLines();
		}
	}

	void DrawLines()
	{
    
		
		if (currentColor != targetColor)
		{
    
			
			if (Mathf.Abs(currentColor.a - targetColor.a) < Mathf.Abs(deltaColor.a) * Time.deltaTime)
			{
    
				currentColor = targetColor;
				deltaColor = new Color(0, 0, 0, 0);
			}
			else
			{
    
				currentColor += deltaColor * Time.deltaTime;
			}

			if (fadeOverlay)
			{
    
				var overlay = SteamVR_Overlay.instance;
				if (overlay != null)
				{
    
					overlay.alpha = 1.0f - currentColor.a;
				}
			}
		}

		if (currentColor.a > 0 && fadeMaterial)
		{
    
			
			fadeMaterial.SetColor(fadeMaterialColorID, currentColor);
			fadeMaterial.SetPass(0);
			GL.Begin(GL.QUADS);

			GL.Vertex3(-1, -1, 0);
			GL.Vertex3( 1, -1, 0);
			GL.Vertex3(1, 1, 0);
			GL.Vertex3(-1, 1, 0);
			GL.End();
		}
	}
}

至此GameThe window has been able to achieve the screen fade in、Fade out and occlude,但VRThe screen inside the helmet remains unchanged;
我们还需要调用OpenVR中的Compositor.FadeToColor方法对VRThe screen inside the helmet is operated;

最终代码

//#define TEST_FADE_VIEW
//======= Copyright (c) Valve Corporation, All rights reserved. ===============
//
// Purpose: CameraFade script adapted to work with SteamVR.
//
// Usage: Add to your top level SteamVR_Camera (the one with ApplyDistoration
// checked) and drag a reference to this component into SteamVR_Camera
// RenderComponents list. Then call the static helper function
// SteamVR_Fade.Start with the desired color and duration.
// Use a duration of zero to set the start color.
//
// Example: Fade down from black over one second.
// SteamVR_Fade.Start(Color.black, 0);
// SteamVR_Fade.Start(Color.clear, 1);
//
// Note: This component is provided to fade out a single camera layer's
// scene view. If instead you want to fade the entire view, use:
// SteamVR_Fade.View(Color.black, 1);
// (Does not affect the game view, however.)
//
//=============================================================================

using UnityEngine;
using UnityEngine.Rendering;
using Valve.VR;

public class SteamVR_Fade : MonoBehaviour
{
    
	private Color currentColor = new Color(0, 0, 0, 0);	// default starting color: black and fully transparent
	private Color targetColor = new Color(0, 0, 0, 0);	// default target color: black and fully transparent
	private Color deltaColor = new Color(0, 0, 0, 0);	// the delta-color is basically the "speed / second" at which the current color should change
	private bool fadeOverlay = false;

	static public void Start(Color newColor, float duration, bool fadeOverlay = false)
	{
    
		SteamVR_Events.Fade.Send(newColor, duration, fadeOverlay);
	}

	static public void View(Color newColor, float duration)
	{
    
		var compositor = OpenVR.Compositor;
		if (compositor != null)
			compositor.FadeToColor(duration, newColor.r, newColor.g, newColor.b, newColor.a, false);
	}

#if TEST_FADE_VIEW
	void Update()
	{
    
		if (Input.GetKeyDown(KeyCode.Space))
		{
    
			SteamVR_Fade.View(Color.black, 0);
			SteamVR_Fade.View(Color.clear, 1);
		}
	}
#endif

	public void OnStartFade(Color newColor, float duration, bool fadeOverlay)
	{
    
		if (duration > 0.0f)
		{
    
			targetColor = newColor;
			deltaColor = (targetColor - currentColor) / duration;
		}
		else
		{
    
			currentColor = newColor;
		}
	}

	static Material fadeMaterial = null;
	static int fadeMaterialColorID = -1;

	void OnEnable()
	{
    
		RenderPipelineManager.endFrameRendering += OnCameraRender;
		if (fadeMaterial == null)
		{
    
			fadeMaterial = new Material(Shader.Find("Custom/SteamVR_Fade"));
			fadeMaterialColorID = Shader.PropertyToID("fadeColor");
		}

		SteamVR_Events.Fade.Listen(OnStartFade);
		SteamVR_Events.FadeReady.Send();
	}

	void OnDisable()
	{
    
		RenderPipelineManager.endFrameRendering -= OnCameraRender;
		SteamVR_Events.Fade.Remove(OnStartFade);
	}
	protected void OnCameraRender(ScriptableRenderContext context, Camera[] cameraList)
	{
    
		foreach (var camera in cameraList)
		{
    
		
				DrawLines();
		}
	}

	void DrawLines()
	{
    
		
		if (currentColor != targetColor)
		{
    
			// if the difference between the current alpha and the desired alpha is smaller than delta-alpha * deltaTime, then we're pretty much done fading:
			if (Mathf.Abs(currentColor.a - targetColor.a) < Mathf.Abs(deltaColor.a) * Time.deltaTime)
			{
    
				currentColor = targetColor;
				deltaColor = new Color(0, 0, 0, 0);
			}
			else
			{
    
				currentColor += deltaColor * Time.deltaTime;
			}

			if (fadeOverlay)
			{
    
				var overlay = SteamVR_Overlay.instance;
				if (overlay != null)
				{
    
					overlay.alpha = 1.0f - currentColor.a;
				}
			}
		}

		if (currentColor.a > 0 && fadeMaterial)
		{
    
			SteamVR_Fade.View(currentColor, 0);
			fadeMaterial.SetColor(fadeMaterialColorID, currentColor);
			fadeMaterial.SetPass(0);
			GL.Begin(GL.QUADS);

			GL.Vertex3(-1, -1, 0);
			GL.Vertex3( 1, -1, 0);
			GL.Vertex3(1, 1, 0);
			GL.Vertex3(-1, 1, 0);
			GL.End();
		}
	}
}