DynamicSplatting.cs

Surface s = _scene.Find<Surface>();

Texture2D t = MaterialPaintGroup.GetMaskTextures((MaterialGroup)s.Material).OfType<Texture2D>().First();

RenderTarget2D target = new RenderTarget2D(GraphicsDevice, t.Width, t.Height);

GraphicsDevice.SetRenderTarget(target);

SpriteBatch sb = new SpriteBatch(GraphicsDevice);

sb.Begin(SpriteSortMode.Immediate, BlendState.AlphaBlend, SamplerState.PointClamp, null, null);

GraphicsDevice.Clear(Color.Transparent);

sb.Draw(t, new Vector2(0f, 0f), null, Color.White, 0f, Vector2.Zero, 1f, SpriteEffects.None, 1f);
sb.Draw(_dynamicMaskTexture, Vector2.Zero, null, Color.White, 0f, new Vector2(_dynamicMaskTexture.Width / 2f, _dynamicMaskTexture.Height / 2f), 1f, SpriteEffects.None, 1f);

sb.End();

GraphicsDevice.SetRenderTarget(null);

MaterialPaintGroup.SetMaskTextures((MaterialGroup)s.Material, new List<Texture2D>() { target });