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GlFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texture, 0) Īllocate and attach a depth buffer (as before). GlTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL)

GlTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR) The following code allocates a framebuffer object with color and depth attachments. See Rendering to a Core Animation Layer.Ī framebuffer intended for offscreen rendering allocates all of its attachments as OpenGL ES renderbuffers. To use the framebuffer in a Core Animation layer composition, use a special Core Animation–aware renderbuffer. See Using Framebuffer Objects to Render to a Texture. To use the framebuffer image as an input to a later rendering step, attach a texture. See Creating Offscreen Framebuffer Objects. To use the framebuffer for offscreen image processing, attach a renderbuffer. In most cases, the difference in configuring the framebuffer is in what object is attached to the framebuffer object’s color attachment point: Creating a Framebuffer Objectĭepending on what task your app intends to perform, your app configures different objects to attach to the framebuffer object. Figure 4-1 Framebuffer with color and depth renderbuffersĪll of these approaches require manually creating framebuffer and renderbuffer objects to store the rendering results from your OpenGL ES context, as well as writing additional code to present their contents to the screen and (if needed) run an animation loop. You might do this so that you can share the same rendering pipeline and OpenGL ES resources between multiple framebuffers. You can also create multiple framebuffer objects in an single rendering context. Later, the texture can act as an input to future rendering commands. You can also attach an OpenGL ES texture to the color attachment point of a framebuffer, which means that any drawing commands are rendered into the texture. The most common image attachment is a renderbuffer object. You provide this storage by attaching images to the framebuffer, as shown in Figure 4-1. When you create a framebuffer object, you have precise control over its storage for color, depth, and stencil data. Drawing to Other Rendering Destinationsįramebuffer objects are the destination for rendering commands. To create high-performance code on GPUs, use the Metal framework instead.