Gl.ColorMaterial (gb.opengl)
Static Sub ColorMaterial ( Face As Integer, Mode As Integer )
Cause a material color to track the current color.
Parameters
- face
-
Specifies whether front,
back,
or both front and back material parameters should track the current color.
Accepted values are
Gl.FRONT,
Gl.BACK,
and Gl.FRONT_AND_BACK.
The initial value is Gl.FRONT_AND_BACK.
- mode
-
Specifies which of several material parameters track the current color.
Accepted values are
Gl.EMISSION,
Gl.AMBIENT,
Gl.DIFFUSE,
Gl.SPECULAR,
and Gl.AMBIENT_AND_DIFFUSE.
The initial value is Gl.AMBIENT_AND_DIFFUSE.
Description
Gl.ColorMaterial specifies which material parameters track the current color.
When Gl.COLOR_MATERIAL is enabled,
the material parameter or parameters specified by
mode,
of the material or materials specified by
face,
track the current color at all times.
To enable and disable Gl.COLOR_MATERIAL, call
Gl.Enable and
Gl.Disable with argument Gl.COLOR_MATERIAL.
Gl.COLOR_MATERIAL is initially disabled.
Notes
Gl.ColorMaterial makes it possible to change a subset of material parameters for each
vertex using only the
Gl.Color command,
without calling Gl.Material.
If only such a subset of parameters is to be specified for each
vertex, calling
Gl.ColorMaterial is preferable to calling Gl.Material.
Call
Gl.ColorMaterial before enabling Gl.COLOR_MATERIAL.
Calling Gl.DrawElements, Gl.DrawArrays, or Gl.DrawRangeElements
may leave the current color indeterminate, if the color array is enabled.
If
Gl.ColorMaterial is enabled while the current color is indeterminate, the
lighting material state specified by
face and
mode is also indeterminate.
If the GL version is 1.1 or greater, and Gl.COLOR_MATERIAL is
enabled, evaluated color values affect the results of the lighting
equation as if the current color were being modified, but no change is
made to the tracking lighting parameter of the current color.
Errors
Gl.INVALID_ENUM is generated if
face or
mode is not an
accepted value.
Gl.INVALID_OPERATION is generated if
Gl.ColorMaterial is executed between
the execution of
Gl.Begin and the corresponding execution of
Gl.End.
Associated Gets
Gl.IsEnabled with argument Gl.COLOR_MATERIAL
Gl.Get with argument Gl.COLOR_MATERIAL_PARAMETER
Gl.Get with argument Gl.COLOR_MATERIAL_FACE
See also
Gl.ColorPointer,
Gl.DrawArrays,
Gl.DrawElements,
Gl.DrawRangeElements,
Gl.Light,
Gl.LightModel,
Gl.Material