glGetTexGen

NAME

glGetTexGendv, glGetTexGenfv, glGetTexGeniv -- return texture coordinate generation parameters

C SPECIFICATION

void glGetTexGendv(GLenum coord,
                   GLenum pname,
                   GLdouble *params)
void glGetTexGenfv(GLenum coord,
                   GLenum pname,
                   GLfloat *params)
void glGetTexGeniv(GLenum coord,
                   GLenum pname,
                   GLint *params)

PARAMETERS

coord
Specifies a texture coordinate. Must be GL_S, GL_T, GL_R, or GL_Q.

pname
Specifies the symbolic name of the value(s) to be returned. Must be either GL_TEXTURE_GEN_MODE or the name of one of the texture generation plane equations: GL_OBJECT_PLANE or GL_EYE_PLANE.

params
Returns the requested data.

DESCRIPTION

glGetTexGen returns in params selected parameters of a texture coordinate generation function that was specified using glTexGen. coord names one of the (s,t,r,q) texture coordinates, using the symbolic constant GL_S, GL_T, GL_R, or GL_Q.

pname specifies one of three symbolic names:

GL_TEXTURE_GEN_MODE
params returns the single-valued texture generation function, a symbolic constant.

GL_OBJECT_PLANE
params returns the four plane equation coefficients that specify object linear-coordinate generation. Integer values, when requested, are mapped directly from the internal floating-point representation.

GL_EYE_PLANE
params returns the four plane equation coefficients that specify eye linear-coordinate generation. Integer values, when requested, are mapped directly from the internal floating-point representation. The returned values are those maintained in eye coordinates. They are not equal to the values specified using glTexGen, unless the modelview matrix was identity at the time glTexGen was called.

NOTES

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

ERRORS

GL_INVALID_ENUM is generated if coord or pname is not an accepted value.

GL_INVALID_OPERATION is generated if glTexGen is called between a call to glBegin and the corresponding call to glEnd.

SEE ALSO

glTexGen


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© 1995 Uwe Behrens. All rights reserved.