fgluLoadSamplingMatrices(3G) OpenGL Reference fgluLoadSamplingMatrices(3G)NAME
fgluLoadSamplingMatrices - load NURBS sampling and culling matrices
FORTRAN SPECIFICATION
SUBROUTINE fgluLoadSamplingMatrices( CHARACTER*8 nurb,
CHARACTER*8 model,
CHARACTER*8 perspective,
CHARACTER*8 view )
PARAMETERS
nurb Specifies the NURBS object (created with
fgluNewNurbsRenderer).
model Specifies a modelview matrix (as from a glGetFloatv call).
perspective Specifies a projection matrix (as from a glGetFloatv call).
view Specifies a viewport (as from a glGetIntegerv call).
DESCRIPTION
fgluLoadSamplingMatrices uses model, perspective, and view to recompute
the sampling and culling matrices stored in nurb. The sampling matrix
determines how finely a NURBS curve or surface must be tessellated to
satisfy the sampling tolerance (as determined by the
GLU_SAMPLING_TOLERANCE property). The culling matrix is used in deciding
if a NURBS curve or surface should be culled before rendering (when the
GLU_CULLING property is turned on).
fgluLoadSamplingMatrices is necessary only if the GLU_AUTO_LOAD_MATRIX
property is turned off (see fgluNurbsProperty). Although it can be
convenient to leave the GLU_AUTO_LOAD_MATRIX property turned on, there
can be a performance penalty for doing so. (A round trip to the GL
server is needed to fetch the current values of the modelview matrix,
projection matrix, and viewport.)
SEE ALSO
fgluGetNurbsProperty, fgluNewNurbsRenderer, fgluNurbsProperty
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