GraphicsTexture.active

描述

当前活动的图形纹理。

所有渲染都进入活动的 GraphicsTexture。如果活动的 GraphicsTexture 为 null，则所有内容都渲染在主窗口中。如果活动的渲染目标是 RenderTexture，则 GraphicsTexture.active 返回 graphicsTexture of RenderTexture.active。

为了将活动渲染目标设置为 GraphicsTexture，它必须在纹理创建时在 GraphicsTextureDescriptor.flags 中启用 GraphicsTextureDescriptorFlags.RenderTarget。

设置 GraphicsTexture.active 等同于使用单个 GraphicsTexture 调用 Graphics.SetRenderTarget。通常，在实现自定义图形效果时，您会更改或查询活动渲染目标；如果您只需要让摄像机渲染到纹理中，则可以使用 RenderTexture 的 Camera.targetTexture。

其他资源：GraphicsTextureDescriptorFlags.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;
    }
}