lau@scrolls.wharton.upenn.edu (Yan K. Lau) (06/06/89)
What is the proper way to "zoom in" on a graphics area in MS Windows?
It would be very awkward to change the logical coordinates of the
grid. The alternative is change what is specified as the physical
coordinates/extents of the display and then move the origin to the
right point. For example, if the program thinks the physical extent
is twice as big (ie. 2X in both directions), it can only display a
quarter of the region on the screen. This looks like a zoom. However,
there seems to be a very small limit on the size of the zoom. Eventually,
the circles (if you were drawing them) will either not be drawn, or
distorted with differing line thickness (appears like paint spills).
So what is the proper way to zoom? Also, what is the proper way to get
device independent points? A pixel is usually too small. But if you
define a filled circle, it gets much bigger on a large 1280x1024 display.
It seems very difficult to get true device independence even in just
trying to locate text a certain distance from a circle.
Yan.
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Yan K. Lau + the last message of a newgroup will be:
)~ + a) longer than one screen &
~/~ lau@scrolls.wharton.upenn.edu + b) something you're not interested in.
/\_ + your decision, 'n' key or space bar?
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