Graphics类

DrawTexture

• ToScreen

    public void Dmainxture()
    {
        GL.PushMatrix();
        //GL.LoadPixelMatrix();
        GL.LoadPixelMatrix(0,Screen.width,Screen.height,0);
        Graphics.DrawTexture(new Rect(0, 0, 200, 100), mainTexture);
        GL.PopMatrix();
    }

在Update中调用会被Camera渲染Clear掉，所以只能在OnGUI和OnPostRender中调用。但是如果将texture绘制到一个RenderTexture中则可以在Update中调用。

• ToTarget

    public void DrawTextureToTarget()
    {
        Graphics.SetRenderTarget(target);
        clearBuffer.Clear();
        clearBuffer.ClearRenderTarget(true, true, clearColor);
        Graphics.ExecuteCommandBuffer(clearBuffer);

        GL.PushMatrix();
        GL.LoadPixelMatrix(0, target.width, target.height, 0);
        //GL.LoadPixelMatrix(0, target.width, 0, target.height);
        Graphics.DrawTexture(new Rect(0, 0, target.width, target.height), mainTexture);
        GL.PopMatrix();
    }

Graphics.SetRenderTarget(target)将绘制结果绘制在一个RenderTexture类型的变量target上，所以屏幕变换需要使用GL.LoadPixelMatrix(0, target.width, target.height, 0)，此时可以在update中调用。

DrawMesh

• Update中调用

    public void DrawMesh()
    {
        Graphics.DrawMesh(Graphics00Mesh.Instance.GetMesh(10, 5), Matrix4x4.identity, material, 0);
        //Graphics.DrawMesh(Graphics00Mesh.Instance.GetMesh(10, 5), center,Quaternion.identity, material, 0);
    }

• OnPostRender中调用

只能使用Graphics.DrawMeshNow方法。

• ToScreen

    private void DrawToScreen()
    {
        drawBuffer.Clear();
        drawBuffer.ClearRenderTarget(true, true, clearColor);
        Graphics.ExecuteCommandBuffer(drawBuffer);

        drawBuffer.DrawMesh(Graphics00Mesh.Instance.GetMesh(triCount, radius), Matrix4x4.identity, mat);
        Graphics.ExecuteCommandBuffer(drawBuffer);
    }

• ToTarget

    private void DrawToTarget()
    {
        GL.PushMatrix();
        Graphics.SetRenderTarget(target);
        GL.LoadPixelMatrix(0, target.width, 0, target.height);

        drawBuffer.Clear();
        drawBuffer.ClearRenderTarget(true, true, clearColor);
        Graphics.ExecuteCommandBuffer(drawBuffer);

        drawBuffer.DrawMesh(Graphics00Mesh.Instance.GetMesh(triCount, radius), Matrix4x4.identity, mat);
        Graphics.ExecuteCommandBuffer(drawBuffer);
        
        GL.PopMatrix();
    }

参考文章

https://www.cnblogs.com/llstart-new0201/p/12315716.html