GraphicsTexture.active

描述

Currently active graphics texture.

All rendering goes into the active GraphicsTexture. If the active GraphicsTexture is null everything is rendered in the main window. If the active render target is a RenderTexture, GraphicsTexture.active will return the graphicsTexture of RenderTexture.active.

In order to set the active render target to a GraphicsTexture, it must have GraphicsTextureDescFlags.RenderTarget enabled in GraphicsTexture.descriptor.flags on texture creation.

Setting GraphicsTexture.active is the same as calling Graphics.SetRenderTarget with a single GraphicsTexture. Typically you change or query the active render target when implementing custom graphics effects; if all you need is to make a Camera render into a texture, then use Camera.targetTexture with a RenderTexture instead.

Additional resources: GraphicsTextureDescFlags.RenderTarget, Graphics.SetRenderTarget, RenderTexture.active.

using UnityEngine;
using UnityEngine.Rendering;
using System.Collections;

// Get the contents of a GraphicsTexture into a Texture2D
public class ExampleClass : MonoBehaviour
{
    static public Texture2D GetGfxTexPixels(GraphicsTexture gfxTex)
    {
        // Remember currently active render target
        GraphicsTexture currentActiveRT = GraphicsTexture.active;

        // Set the supplied GraphicsTexture as the active one
        GraphicsTexture.active = gfxTex;

        // Create a new Texture2D and read the GraphicsTexture image into it
        Texture2D tex = new Texture2D(gfxTex.descriptor.width, gfxTex.descriptor.height);
        tex.ReadPixels(new Rect(0, 0, tex.width, tex.height), 0, 0);
        tex.Apply();

        // Restore previously active render texture
        GraphicsTexture.active = currentActiveRT;
        return tex;
    }
}