1991-2006
Silicon Graphics, Inc.
glPushMatrix
3G

# glPushMatrix

push and pop the current matrix stack

## C Specification

                    void glPushMatrix
                     void

## C Specification

                    void glPopMatrix
                     void

## Description

There is a stack of matrices for each of the matrix modes. In `GL_MODELVIEW` mode, the stack depth is at least 32. In the other modes, `GL_COLOR`, `GL_PROJECTION`, and `GL_TEXTURE`, the depth is at least 2. The current matrix in any mode is the matrix on the top of the stack for that mode.

`glPushMatrix` pushes the current matrix stack down by one, duplicating the current matrix. That is, after a `glPushMatrix` call, the matrix on top of the stack is identical to the one below it.

glPopMatrix pops the current matrix stack, replacing the current matrix with the one below it on the stack.

Initially, each of the stacks contains one matrix, an identity matrix.

It is an error to push a full matrix stack or to pop a matrix stack that contains only a single matrix. In either case, the error flag is set and no other change is made to GL state.

## Errors

`GL_STACK_OVERFLOW` is generated if `glPushMatrix` is called while the current matrix stack is full.

`GL_STACK_UNDERFLOW` is generated if glPopMatrix is called while the current matrix stack contains only a single matrix.

`GL_INVALID_OPERATION` is generated if `glPushMatrix` or glPopMatrix is executed between the execution of glBegin and the corresponding execution of glEnd.

## Associated Gets

glGet with argument `GL_MATRIX_MODE`

glGet with argument `GL_COLOR_MATRIX`

glGet with argument `GL_MODELVIEW_MATRIX`

glGet with argument `GL_PROJECTION_MATRIX`

glGet with argument `GL_TEXTURE_MATRIX`

glGet with argument `GL_COLOR_MATRIX_STACK_DEPTH`

glGet with argument `GL_MODELVIEW_STACK_DEPTH`

glGet with argument `GL_PROJECTION_STACK_DEPTH`

glGet with argument `GL_TEXTURE_STACK_DEPTH`

glGet with argument `GL_MAX_MODELVIEW_STACK_DEPTH`

glGet with argument `GL_MAX_PROJECTION_STACK_DEPTH`

glGet with argument `GL_MAX_TEXTURE_STACK_DEPTH`

## See Also

glFrustum, glLoadIdentity, glLoadMatrix, glLoadTransposeMatrix, glMatrixMode, glMultMatrix, glMultTransposeMatrix, glOrtho, glRotate, glScale, glTranslate, glViewport

## 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/.