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Gl.Rectf (gb.opengl)

Static Sub Rectf ( X1 As Float, Y1 As Float, X2 As Float, Y2 As Float )

draw a rectangle.

Parameters

x1, y1

Specify one vertex of a rectangle.
x2, y2

Specify the opposite vertex of the rectangle.

Parameters

v1

Specifies a pointer to one vertex of a rectangle.
v2

Specifies a pointer to the opposite vertex of the rectangle.

Description

Gl.Rect 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 containing an x y pair. The resulting rectangle is defined in the z 0 plane.

Gl.Rect(x1, y1, x2, y2) is exactly equivalent to the following sequence:
glBegin(Gl.POLYGON);
glVertex2(x1, y1);
glVertex2(x2, y1);
glVertex2(x2, y2);
glVertex2(x1, y2);
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 Gl.Rect is executed between the execution of Gl.Begin and the corresponding execution of Gl.End.

See also

Gl.Begin, Gl.Vertex

See original documentation on OpenGL website