The Rectangle primitive draws a rectangle whose sides are parallel to the vertical and horizontal axis of displayed video. The primitive uses six (6) pa- rameters. The first is the color. The next two param- eters are the width and height of the rectangle in pixels. The second two parameters are the X and Y coordinates for the top left-hand corner of the rect- angle. The last parameter is the fill flag. The follow- ing example draws a 50% gray rectangular filled solid that is 15 pixels wide by 20 pixels high and has its top left corner located 50 pixels to the right and 40 pixels below the top left corner of active video:

Rectangle Gray50 15 2Ø 5Ø 4Ø 1

The Oval primitive draws an oval whose axes are parallel to the vertical and horizontal axis of dis- played video. The size and position of the oval is defined by its framing rectangle. The framing rect- angle is a rectangle whose sides are both tangent to the oval at four points and are parallel to the verti- cal and horizontal axis of displayed video. The fram- ing rectangle is not drawn as part of the primitive. The figure shows the relationship of an oval to its framing rectangle.

left, top

height

width

The primitive uses six (6) parameters. The first is the color. The next two parameters are the width and height of the framing rectangle in pixels. The second two parameters are the X and Y coordinates for the top left-hand corner of the framing rectangle. The last parameter is the fill flag. The following example draws a red oval that is 240 pixels wide by 150 pixels high and has the framing rectangle’s top left corner located 20 pixels to the right and 10 pix- els below the top left corner of active video:

Oval Red 24Ø 15Ø 2Ø 1Ø Ø

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Chapter 6: Programming

Model 801GC, 801GF & 801GX¥Rev. A

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Quantum Data 801GC, 801GF, 801GX manual Rectangle Gray50 15 2Ø 5Ø 4Ø