Once you are done rendering to this texture, you can use it like any other texture. It lacked quite a bit of the above functionality, which later extensions granted. They are treated as though they were an array cubemap with one layer so 6 layer-faces. You should use the core Framebuffer Object functionality if at all possible. Note that glGenerateMipmap is also included as part of FBO extension in order to generate mipmaps explicitly after modifying the base level texture image. This can be done by using glRenderbufferStorage. It is much faster to switch framebuffer-attachable images than to switch between FBOs.

Uploader: Gum
Date Added: 21 May 2004
File Size: 54.60 Mb
Operating Systems: Windows NT/2000/XP/2003/2003/7/8/10 MacOS 10/X
Downloads: 12070
Price: Free* [*Free Regsitration Required]

Remember that textures are a set of images.

Framebuffer Object – OpenGL Wiki

It is perfectly valid g, bind one image from a texture to an FBO and then render with that texture, as long as you prevent yourself from sampling from that image. You should only set these values if you intend to use the FBO without images.

There are also a number of other issues with regard to sizes of images and so forth that framebuffrr be detected in order to be able to safely use the FBO.

Because we want to see these textures we have to create a basic vertex shader to draw a quad in NDC and texture it in fragment shader. Same as other Obejct objects, you have to bind the current renderbuffer object before referencing it. We draw the depth texture from Pass 1 into a quad from Pass 2.


This example is nearly identical to the above sample code with one difference: So separate “images” within a single mipmap level of an array texture do not count as separate, so you will get UB if you try to write to one while reading from another. Switching framebuffer-attachable images is much faster than switching between FBOs. We do not want to render to a ibject buffer. A renderbuffer image can be attached by calling glFramebufferRenderbuffer.

Frmebuffer a texture object is deleted while it is still attached to a FBO, then, the texture image will be automatically detached from the currently bound FBO. If you ever get any of these values from glCheckFramebufferStatusit is because your program has done something wrong in setting up the FBO. However, FBO does not suffer from this clipping problem. Framebuffer Object Core in version 4.

It returns non-zero value after checking the FBO.

And if an image of a renderbuffer object is attached to a framebuffer, then OpenGL performs “offscreen rendering”. Obviously none of the fragment shader outputs will be written to anywhere in this case, but rendering can otherwise proceed as normal.

Also called a D24S8 format. Pass2 is the final pass. Notice that there is no restriction based on size. You are not required to call this manually.


If you want depth with no stencil, you can use one of the required depth formats. You can use it to generate mipmaps whenever you want. Otherwise, the FBO status is incomplete. This is useful for using arbitrary reading and framebugfer of image data from shaders, rather than writing to a bound framebuffer. FBO itself does not have any image storage buffer in it.

One FBO for each group. Download the source and binary: By using framebuffer object FBOan OpenGL application can redirect the rendering output to the application-created framebuffer object FBO other than the traditional window-system-provided framebuffer.

Framebuffer Object Extension Examples

Creating framebuffer objects is similar to generating vertex buffer objects VBO. The fourth parameter is the identifier of the texture object.

For cubemaps, this is always exactly 6 layers: An FBO that is valid for use is said to be “framebuffer complete”. It lacked quite a bit of the above functionality, which later extensions granted. Multiple texture objects or renderbuffer objects can be attached to a framebuffer object through the attachment points.