glGetPixelMap

glGetPixelMapfv, glGetPixelMapuiv, glGetPixelMapusv: return the specified pixel map.

C Specification

void glGetPixelMapfv(
    GLenum	 map,
    GLfloat	 *values)
void glGetPixelMapuiv(
    GLenum	 map,
    GLuint	 *values)
void glGetPixelMapusv(
    GLenum	 map,
    GLushort	 *values)

Parameters

map: Specifies the name of the pixel map to return. Accepted values are GL_PIXEL_MAP_I_TO_I, GL_PIXEL_MAP_S_TO_S, GL_PIXEL_MAP_I_TO_R, GL_PIXEL_MAP_I_TO_G, GL_PIXEL_MAP_I_TO_B, GL_PIXEL_MAP_I_TO_A, GL_PIXEL_MAP_R_TO_R, GL_PIXEL_MAP_G_TO_G, GL_PIXEL_MAP_B_TO_B, and GL_PIXEL_MAP_A_TO_A.
values: Returns the pixel map contents.

See the glPixelMap reference page for a description of the acceptable values for the map parameter. glGetPixelMap returns in values the contents of the pixel map specified in map. Pixel maps are used during the execution of glReadPixels, glDrawPixels, glCopyPixels, glTexImage1D, and glTexImage2D to map color indices, stencil indices, color components, and depth components to other values.

Unsigned integer values, if requested, are linearly mapped from the internal fixed or floating-point representation such that 1.0 maps to the largest representable integer value, and 0.0 maps to 0. Return unsigned integer values are undefined if the map value was not in the range [0, 1].

To determine the required size of map, call glGet with the appropriate symbolic constant.

Notes

If an error is generated, no change is made to the contents of values.

Errors

GL_INVALID_ENUM is generated if map is not an accepted value.
GL_INVALID_OPERATION is generated if glGetPixelMap is executed between the execution of glBegin and the corresponding execution of glEnd.

Associated Gets

glGet with argument GL_PIXEL_MAP_I_TO_I_SIZE
glGet with argument GL_PIXEL_MAP_S_TO_S_SIZE
glGet with argument GL_PIXEL_MAP_I_TO_R_SIZE
glGet with argument GL_PIXEL_MAP_I_TO_G_SIZE
glGet with argument GL_PIXEL_MAP_I_TO_B_SIZE
glGet with argument GL_PIXEL_MAP_I_TO_A_SIZE
glGet with argument GL_PIXEL_MAP_R_TO_R_SIZE
glGet with argument GL_PIXEL_MAP_G_TO_G_SIZE
glGet with argument GL_PIXEL_MAP_B_TO_B_SIZE
glGet with argument GL_PIXEL_MAP_A_TO_A_SIZE
glGet with argument GL_MAX_PIXEL_MAP_TABLE