- draw a rectangle
C SPECIFICATION
PARAMETERS
_param1, _param2 Specify one vertex of a rectangle.
_param3, _param4 Specify the opposite vertex of the rect-
angle.
C SPECIFICATION
PARAMETERS
_param1
Specifies a pointer to one vertex of a rectangle.
_param2
Specifies a pointer to the opposite vertex of the
rectangle.
DESCRIPTION
glRect supports efficient specification of rectangles as
two corner points. Each rectangle command takes four
arguments, organized either as two consecutive pairs of
(x,y) coordinates, or as two pointers to arrays, each con-
taining an (x,y) pair. The resulting rectangle is defined
in the z = 0 plane.
glRect(_param1(1), _param2(1), _param3(1), _param4(1)) is
exactly equivalent to the following sequence: glBegin(-
GL_POLYGON); glVertex2(_param1(1), _param2(1)); glVer-
tex2(_param3(1), _param2(1)); glVertex2(_param3(1),
_param4(1)); glVertex2(_param1(1), _param4(1)); glEnd();
Note that if the second vertex is above and to the right
of the first vertex, the rectangle is constructed with a
counterclockwise winding.
ERRORS
GL_INVALID_OPERATION is generated if glRect is executed
between the execution of glBegin and the corresponding
execution of glEnd.
SEE ALSO
glBegin, glVertex
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