Radio Shack TRS-80 - Page 23

Operation Manual computer Graphics
----------TRS·BO ® ----------
v
v
x...---4,.-----4----4- ......
x...-----t-t-+--- .....
X·Axls Ellipse (ar < .5)
V-Axis
Ellipse (ar > .5)
Figure I'. CIRCLE's Ellipse
The range for aspect ratio is a single-precisio~8
floating-point number greater than ••• (to 1*1. >.
Although a negative value will be accepted by BASICG, the
results of using a negative value are unpredictable.
Hints and Tips about aspect ratio:
•
Entering .5 as the ratio produces a circle •
Numbers
between. and .5 produce an ellipse with a
major axis on X.
Numbers over .5 generate an ellipse with a major axis
on Y.
Even though you can enter large aspect ratios, large
numbers may produce straight lines.
Examples
CIRCLE (32.,12'>,9.,1
This exa~ple draws a white-bordered circle with the
centerpolnt of (32.,l2~> and radius of 9 ••
CIRCLE (32.,12.>,9.,1",.7
This statement draws a white-bordered ellipse with an origin
of (32',12'> and radius of 9.. The major axis is the
Y-axis.
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