Quantum Data 801GC, 801GF, 801GX, Руководство владельца и программиста

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6-28
Chapter 6: Programming
Model 801GC, 801GF & 801GX¥Rev. A
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:
R e c t a n g l e G r a y 5 0 1 5 2 Ø 5 Ø 4 Ø 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.
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
width
height
left, top