# glPushMatrix

Definition: | include pGUI.e include opengl.e glPushMatrix() ... glPopMatrix()
Description: | Deprecated, specifically not supported on WebGL. While still supported on desktop/Phix, these routines have been coloured illegal to indicate they cannot be handled by pwa/p2js. The glPushMatrix and glPopMatrix procedures push and pop the current matrix stack.
pwa/p2js: | Not supported.
Remarks | 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 the OpenGL state. These routines do not return a value, however glGetError() can return GL_STACK_OVERFLOW if glPushMatrix was called while the current matrix stack was full, and GL_STACK_UNDERFLOW if glPopMatrix was called while the current matrix stack contained only a single matrix. If either routine is called between glBegin() and glEnd(), glGetError() will return GL_INVALID_OPERATION. 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. The glPushMatrix function 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. The glPopMatrix function 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. The following functions retrieve information related to glPushMatrix and glPopMatrix: 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: | glBegin, glEnd, glFrustum, glGetError, glLoadIdentity, glMatrixMode, glOrtho, glRotate, glScale, glTranslate, glViewport DEV See also --glBegin --glEnd --glFrustum --glLoadIdentity glLoadMatrix --glMatrixMode glMultMatrix --glOrtho //glRotate //glScale //glTranslate //glViewport