OpenGL ES 3.0 Fragment buffer Objects (FBO) details (ii)

We can use frame buffer objects to achieve off-screen rendering. Frame buffer objects support the following operations

1. Create a Frame buffer object using only the OpenGL ES function.

2. Create multiple FBO using EGL context.

3. Create the off-screen color, depth, template render buffer, and texture, and bind them to the frame buffer object.

4. Share color, depth, and template buffer content through multiple buffers.

5. The texture is directly linked to the frame buffer as a color and depth, avoiding the use of copy operations.

Replication between 6.FBO and invalid FBO.

Framebuffer and Renderbuffer objects frame buffer objects and render buffer objects

　　The render buffer object is an application-allocated 2D image buffer. The render buffer is used to store color, depth, or template values that can be associated with a frame buffer object as a color, depth, or template. The render buffer and the operating system-provided off-screen drawing window pbuffer have many similarities. The render buffer cannot be used directly by GL as a texture.

FBO is a collection of color, depth, and template textures or render targets. Various 2D images can be linked to the color points of the frame buffer object.

　　

Create FBO and Rbo

　　

Using Render buffer objects

　　

Note Glgenrenderbuffers does not require a render buffer object name to be allocated before using Glbindrenderbuffer to bind the buffer. Although it is a good practice to call glgenrenderbuffers, there are still many applications that specify constants for their buffers at compile time. The application can specify a render buffer object name that is not used to execute glbindrenderbuffer. We recommend using the name returned by Glgenrenderbuffers instead of the application to specify the buffer name itself.

Once the render buffer object is bound, we can specify the size and format of the stored image within the render buffer

　　

Using FBO

　　

　　

　　

　　

OpenGL ES 3.0 Fragment buffer Objects (FBO) detailed (ii)