glDepthRange(3G)glDepthRange(3G)NAMEglDepthRange - specify mapping of depth values from normalized device
coordinates to window coordinates
SYNOPSIS
void glDepthRange(
GLclampd zNear,
GLclampd zFar );
PARAMETERS
Specifies the mapping of the near clipping plane to window coordinates.
The initial value is 0. Specifies the mapping of the far clipping
plane to window coordinates. The initial value is 1.
DESCRIPTION
After clipping and division by w, depth coordinates range from -1 to 1,
corresponding to the near and far clipping planes. glDepthRange()
specifies a linear mapping of the normalized depth coordinates in this
range to window depth coordinates. Regardless of the actual depth buf‐
fer implementation, window coordinate depth values are treated as
though they range from 0 through 1 (like color components). Thus, the
values accepted by glDepthRange() are both clamped to this range before
they are accepted.
The setting of (0,1) maps the near plane to 0 and the far plane to 1.
With this mapping, the depth buffer range is fully utilized.
NOTES
It is not necessary that zNear be less than zFar. Reverse mappings such
as "zNear" = 1, and "zFar" = 0 are acceptable.
ERRORS
GL_INVALID_OPERATION is generated if glDepthRange() is executed between
the execution of glBegin() and the corresponding execution of glEnd().
ASSOCIATED GETSglGet() with argument GL_DEPTH_RANGE
SEE ALSOglDepthFunc(3), glPolygonOffset(3), glViewport(3)glDepthRange(3G)
