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Porting greset

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OpenGL replaces the IRIS GL function, greset, with the functions, glPushAttrib and glPopAttrib. Use these functions to save and restore groups of state variables. For example,

void glPushAttrib( GLbitfield mask );

This example takes a bitwise OR of symbolic constants, indicating which groups of state variables to push onto an attribute stack. Each constant refers to a group of state variables. The following table shows the attribute groups with their equivalent symbolic constant names. For a complete list of the OpenGL state variables associated with each constant, see glPushAttrib.

Attribute Constant
accumulation buffer clear value GL_ACCUM_BUFFER_BIT
color buffer GL_COLOR_BUFFER_BIT
current GL_CURRENT_BIT
depth buffer GL_DEPTH_BUFFER_BIT
enable GL_ENABLE_BIT
evaluators EGL_VAL_BIT
fog GL_FOG_BIT
GL_LIST_BASE setting GL_LIST_BIT
hint variables GL_HINT_BIT
lighting variables GL_LIGHTING_BIT
line drawing mode GL_LINE_BIT
pixel mode variables GL_PIXEL_MODE_BIT
point variables GL_POINT_BIT
polygon GL_POLYGON_BIT
polygon stipple GL_POLYGON_STIPPLE_BIT
scissor GL_SCISSOR_BIT
stencil buffer GL_STENCIL_BUFFER_BIT
texture GL_TEXTURE_BIT
transform GL_TRANSFORM_BIT
viewport GL_VIEWPORT_BIT
GL_ALL_ATTRIB_BITS

 

To restore the values of the state variables to those saved with the last glPushAttrib, simply call glPopAttrib. The variables you didn't save will remain unchanged. The attribute stack has a finite depth of at least 16.