void glScissor(GLint x, GLint y, GLsizei width, GLsizei height)
The scissor test is enabled and disabled using glEnable and glDisable with argument GL_SCISSOR_TEST. While the scissor test is enabled, only pixels that lie within the scissor box can be modified by drawing commands. Window coordinates have integer values at the shared corners of frame buffer pixels, so glScissor(0, 0, 1, 1) allows only the lower left pixel in the window to be modified, and glScissor(0, 0, 0, 0) disallows modification to all pixels in the window.
When the scissor test is disabled, it is as though the scissor box includes the entire window.
GL_INVALID_OPERATION is generated if glScissor is called between a call to glBegin and the corresponding call to glEnd.
back to the OpenGL index page
© 1995 Uwe Behrens. All rights reserved.