void glMapGrid1d(GLint un, GLdouble u1, GLdouble u2) void glMapGrid1f(GLint un, GLfloat u1, GLfloat u2) void glMapGrid2d(GLint un, GLdouble u1, GLdouble u2, GLint vn, GLdouble v1, GLdouble v2) void glMapGrid2f(GLint un, GLfloat u1, GLfloat u2, GLint vn, GLfloat v1, GLfloat v2)
glMapGrid1 and glMapGrid2 specify the linear grid mappings between the i (or i and j) integer grid coordinates, to the u (or u and v) floating-point evaluation map coordinates. See glMap1 and glMap2 for details of how u and v coordinates are evaluated.
glMapGrid1 specifies a single linear mapping such that integer grid coordinate 0 maps exactly to u1, and integer grid coordinate un maps exactly to u2. All other integer grid coordinates i are mapped such that
glMapGrid2 specifies two such linear mappings. One maps integer grid coordinate i = 0 exactly to u1, and integer grid coordinate i = un exactly to u2. The other maps integer grid coordinate j = 0 exactly to v1, and integer grid coordinate j = vn exactly to v2. Other integer grid coordinates i and j are mapped such that
v = j(v2 - v1) / vn + v1
The mappings specified by glMapGrid are used identically by glEvalMesh and glEvalPoint.
GL_INVALID_OPERATION is generated if glMapGrid is called between a call to glBegin and the corresponding call to glEnd.
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© 1995 Uwe Behrens. All rights reserved.