1991-2006 Silicon Graphics, Inc. glMapGrid 3G glMapGrid define a one- or two-dimensional mesh C Specification 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 Parameters un Specifies the number of partitions in the grid range interval [u1, u2]. Must be positive. u1 u2 Specify the mappings for integer grid domain values i = 0 and i = un . vn Specifies the number of partitions in the grid range interval [v1, v2] (glMapGrid2 only). v1 v2 Specify the mappings for integer grid domain values j = 0 and j = vn (glMapGrid2 only). Description glMapGrid and glEvalMesh are used together to efficiently generate and evaluate a series of evenly-spaced map domain values. glEvalMesh steps through the integer domain of a one- or two-dimensional grid, whose range is the domain of the evaluation maps specified by glMap1 and glMap2. 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 so that u = i u2 - u1 un + u1 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 u = i u2 - u1 un + u1 v = j v2 - v1 vn + v1 The mappings specified by glMapGrid are used identically by glEvalMesh and glEvalPoint. Errors GL_INVALID_VALUE is generated if either un or vn is not positive. GL_INVALID_OPERATION is generated if glMapGrid is executed between the execution of glBegin and the corresponding execution of glEnd. Associated Gets glGet with argument GL_MAP1_GRID_DOMAIN glGet with argument GL_MAP2_GRID_DOMAIN glGet with argument GL_MAP1_GRID_SEGMENTS glGet with argument GL_MAP2_GRID_SEGMENTS See Also glEvalCoord, glEvalMesh, glEvalPoint, glMap1, glMap2 Copyright Copyright 1991-2006 Silicon Graphics, Inc. This document is licensed under the SGI Free Software B License. For details, see http://oss.sgi.com/projects/FreeB/.