GLONEMINUSCONSTANTCOLOR

GLONEMINUSCONSTANTCOLOR is the naming convention used to refer to the OpenGL blending factor GL_ONE_MINUS_CONSTANT_COLOR. It designates the component-wise complement of a previously defined constant color and is used in the blending stage of the graphics pipeline to determine how the source and destination colors are combined during fragment processing.

In OpenGL blending, a constant color can be defined with a function such as glBlendColor, which sets a fixed color value across all frames or render passes. The factors GL_ONE_MINUS_CONSTANT_COLOR apply to the RGB channels by producing, for each channel, a factor equal to 1 minus the corresponding component of the constant color. This factor is then used in the blending equation alongside other source and destination factors to compute the final color of the pixel. The alpha channel has its own related factor, GL_ONE_MINUS_CONSTANT_ALPHA, when separate alpha blending is used.

Usage and configuration notes: GL_ONE_MINUS_CONSTANT_COLOR is used as part of the blending state, typically specified with glBlendFunc or glBlendFuncSeparate. It requires blending to be enabled (glEnable(GL_BLEND)) and a constant color to be defined via glBlendColor. The constant color components are clamped to the range [0, 1], and the effect applies to the RGB channels of the color buffer unless an alternative configuration is chosen for alpha.

See also: GL_ONE, GL_ZERO, GL_CONSTANT_COLOR, GL_CONSTANT_ALPHA, GL_ONE_MINUS_CONSTANT_ALPHA.