Radio Shack TRS-80 - Page 59

Computer Graphics Operation Manual
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viewport. A line is drawn but only a segment is within the
parameters of the viewport.
&VIEW (function)
Returns Viewport Coordinates
&VIEW returns a corner coordinate of a viewport. It is
important to note the parentheses are not optional. If you
enter the &VIEW function without the parentheses, a Syntax
Error will result.
To display one of the four viewport coordinates, you must
enter one of the following values for p:
~ returns the upper left X-coordinate
1 returns the upper left Y-coordinate
2 returns the lower right X-coordinate
3 returns the lower right Y-coordinate
Important Note: When you have defined several viewports,
&VIEW only returns the coordinates of the last-defined
viewport.
Examples
Set up the following viewport:
VIEW(1~~,8~)-(22~,15~),~,1
Now type:
Displays:
Type:
Displays:
PRINT &VIEW(~) <ENTER>
PRINT
&VIEW(l) <ENTER>
8~
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