Hello, I am performing some tests with render to texture operations. My aim is to be able to have the same result (or very very close) rendering directly to the backbuffer and rendering to a texture. The tricky part is that I am dealing with blended primitives. Doing so brings some problems I do not know how to solve at the moment. I hope you can help me! - The first, and most important point, is that the resulting opacity is not the same when rendering to the texture. - The second one is that when the texture is cleared for rendering, it introduce some color artifacts on transparent fragments. http://zavie.free.fr/test You can find here some screenshots showing what my problem is, and a zipfile containing the files used to make this example. The white and black part in the background is always rendered directly. The transparent textured squares are rendered directly on one screenshot, and via texture on the two other ones (the red square highlights the texture used for the rendering). As you can see, when rendering to the texture, it results more transparent. I already spent a lot of time on that problem, and I really hope you can help me. So I am offering a Gmail account for the solution ;-) P.S. : I am not considerating aliasing artifacts due to texture resolution, neither tiny shifts introduced by bad frustrum.