Blending Extensions

Blending Extensions

Blending refers to the process of combining color values from a source (an incoming pixel fragment) with current values of the stored pixel in the framebuffer (the destination). The final effect is that parts of a scene appear translucent. In OpenGL 1.0, you specify the blending operation by calling glBlendFunc(), then enable or disable blending using glEnable() or glDisable() with GL_BLEND.

Blending is discussed in the first section of Chapter 7, "Blending, Antialiasing, and Fog," of the OpenGL Programming Guide. The section also lists a number of sample uses of blending.

This section explains how to use extensions that support color blending for images and rendered geometry in a variety of ways:

"The Constant Color Blending Extension"
"The Minmax Blending Extension"
"The Logical Operation Blending Extension"
"The Blend Subtract Extension"

The Constant Color Blending Extension
The Minmax Blending Extension
The Logical Operation Blending Extension
The Blend Subtract Extension