使用纹理作为渲染目标时的大小限制

Question

我想创建一个纹理并渲染到它的表面但我有一个问题：当纹理大小很大（超过263x263像素ARGB）时，表面上没有渲染基元（我只能看到颜色在清除操作期间使用。）

这是我的代码：

    private void Form1_Load(object sender, EventArgs e)
    {
        // Setting up DirectX
        PresentParameters pp = new PresentParameters()
        {
            BackBufferCount = 1,
            Windowed = true,
            SwapEffect = SwapEffect.Discard,
            BackBufferWidth = ClientSize.Width,
            BackBufferHeight = ClientSize.Height,
        };

        d3d = new Direct3D();
        device = new Device(d3d, 0, DeviceType.Hardware, Handle, CreateFlags.HardwareVertexProcessing, pp);

        TexturedVertex.SetVertexDeclaration(device);

        // Creating a triangle
        triangleBuffer = new VertexBuffer(device, 3 * Marshal.SizeOf(typeof(TexturedVertex)), Usage.WriteOnly, VertexFormat.None, Pool.Managed);

        var stream1 = triangleBuffer.Lock(0, 0, LockFlags.None);
        stream1.WriteRange(new[] {
                            new TexturedVertex( -2, -2, 0, 0, 0 ),
                            new TexturedVertex( 0, 2, 0, 1, 0),
                            new TexturedVertex( 2, -2, 0, 1, 1),
                    });

        triangleBuffer.Unlock();

        // Creating a rect
        rectBuffer = new VertexBuffer(device, 4 * Marshal.SizeOf(typeof(TexturedVertex)), Usage.WriteOnly, VertexFormat.None, Pool.Managed);

        var stream2 = rectBuffer.Lock(0, 0, LockFlags.None);
        stream2.WriteRange(new[] {
                            new TexturedVertex( -2, -2, 0, 0, 0 ),
                            new TexturedVertex( -2, 2, 0, 0, 1),
                            new TexturedVertex( 2, -2, 0, 1, 0),
                            new TexturedVertex( 2, 2, 0, 1, 1),
                    });

        TexturedVertex.SetVertexDeclaration(device);
        rectBuffer.Unlock();

        // Creating a render texture
        int w = 262;
        Texture texture = new Texture(device, w, w, 0, Usage.RenderTarget, Format.A8R8G8B8, Pool.Default);

        Surface surface = texture.GetSurfaceLevel(0);
        Surface buffer = device.GetRenderTarget(0);

        device.SetRenderTarget(0, surface);

        device.SetTransform(TransformState.Projection, Matrix.OrthoOffCenterLH(-4, 4, -4, 4, 0, 100));
        device.SetTransform(TransformState.View, Matrix.Identity);
        device.SetTransform(TransformState.World, Matrix.Identity);

        device.Clear(ClearFlags.Target, new Color4(Color.Green), 0, 0);

        device.BeginScene();

        device.SetStreamSource(0, triangleBuffer, 0, Marshal.SizeOf(typeof(TexturedVertex)));
        device.DrawPrimitives(PrimitiveType.TriangleStrip, 0, 3);

        device.EndScene();
        device.Present();

        device.SetRenderTarget(0, buffer);

        // Setting current texture and material
        device.SetTexture(0, texture);
        Material mat = new Material();
        mat.Ambient = mat.Diffuse = mat.Emissive = Color.White;
        device.Material = mat;

        // Setting the projection, view and transform matrix
        device.SetTransform(TransformState.Projection, Matrix.OrthoOffCenterLH(-4, 4, -4, 4, 0, 100));
        device.SetTransform(TransformState.View, Matrix.Identity);
        device.SetTransform(TransformState.World, Matrix.Identity);


        // Setting handler
        this.KeyDown += new KeyEventHandler(Form1_KeyDown);
        this.Paint += new PaintEventHandler(Form1_Paint);
    }

    void Form1_Paint(object sender, PaintEventArgs e)
    {
        device.Clear(ClearFlags.Target, new Color4(Color.Purple), 0, 0);

        device.BeginScene();

        device.SetStreamSource(0, rectBuffer, 0, Marshal.SizeOf(typeof(TexturedVertex)));
        //device.SetStreamSource(0, triangleBuffer, 0, Marshal.SizeOf(typeof(TexturedVertex)));

        device.DrawPrimitives(PrimitiveType.TriangleStrip, 0, 4);

        device.EndScene();

        device.Present();
    }