At 3:18 PM -0800 12/9/01, Mr. Weasel Willits wrote:
The way I see it, REALbasic should update that area without calling the
paint event forcing us to redraw it. Why?
To me a better question is: How? How is RB supposed to guess what
you want to be shown in the newly-exposed area? Perhaps if we'd
managed to finish that "DWIM" (Do What I Mean) control, we could do
it, but otherwise...
To me the purpouse of the scroll method is to let REALbasic refresh the canvas
based on it's current .graphics data. Doesn't that make sense?
No, because Graphics objects don't HAVE any data other than current
text font, size, style, and foreground color. That's it. A
Graphics object is an interface for drawing; it is NOT a storage area
for graphics data. When you draw to a Graphics object, the drawing
is immediate, not retained. There is no memory of what has been
drawn in the past, nor any way to predict what you might want to draw
in the future.
The only object in standard RB which retains graphics is the Picture
class. But a canvas doesn't have a Picture -- except for its
Backdrop, which it does indeed draw for you.
HTH,
- Joe
--
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| Joseph J. Strout REAL Software, Inc. |
| joe at realsoftware dot com http://www.realsoftware.com |
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