**glPushMatrix**, **glPopMatrix**

### NAME

**glPushMatrix**, **glPopMatrix** -- push and pop the current matrix stack
### C SPECIFICATION

void **glPushMatrix**(void *void*)

### C SPECIFICATION

void **glPopMatrix**(void *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 two
modes, **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 the 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 **glPopAttrib** is called while
the current matrix stack contains only a single matrix.

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

### ASSOCIATED GETS

**glGet** with argument
**GL_MATRIX_MODE**

**glGet** with argument
**GL_MODELVIEW_MATRIX**

**glGet** with argument
**GL_PROJECTION_MATRIX**

**glGet** with argument
**GL_TEXTURE_MATRIX**

**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**,
**glMatrixMode**,
**glMultMatrix**,
**glOrtho**,
**glRotate**,
**glScale**,
**glTranslate**,
**glViewport**

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© *1995 Uwe Behrens. All rights reserved.*