HP Workstation zx2000 OpenGL 1.1 Reference for HP-UX 11.x - Page 322
gluPerspective,
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P gluPerspective Notes Depth buffer precision is affected by the values specified for zNear and zFar. The greater the ratio of zFar to zNear is, the less effective the depth buffer will be at distinguishing between surfaces that are near each other. If r = zFar / zNear, roughly log2 r bits of depth buffer precision are lost. Because r approaches infinity as zNear approaches 0, zNear must never be set to 0. See Also glFrustum, glLoadIdentity, glMultMatrix, gluOrtho2D 322 Chapter 14
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 |
 |
P
gluPerspective
Chapter 14
322
Notes
Depth buffer precision is affected by the values specified for
zNear
and
zFar
. The greater
the ratio of
zFar
to
zNear
is, the less effective the depth buffer will be at distinguishing
between surfaces that are near each other. If
r = zFar / zNear
, roughly log
2
r
bits of
depth buffer precision are lost. Because r approaches infinity as
zNear
approaches 0,
zNear
must never be set to 0.
See Also
glFrustum,
glLoadIdentity,
glMultMatrix,
gluOrtho2D