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Re: Zooming in Object Graphics
I don't want to open a can of worms, but...
This topic always reminds me of Randall Frank's recommendation to use
natural data coordinates rather than normalized data coordinates. I have
only done the graphics in natural coordinates a couple of times, so I'm
skating on thin ice with wobbly ankles. Zooming seems like a place where
it might be especially useful; of course, it's just a hunch and I've yet
to try it.
The ViewPlane_Rect would have to change as well as the location of the
axes/annotations (unless you didn't care to see them when zooming, kind
of like zooming on a bitmap.) The data ranges can be controlled by the
[XYZ]RANGE keywords. The tricky part is setting up the ViewPlane_Rect
so there will be enough room for the axes, etc. I know I build in the
border when making object graphics in normalized coordinates
(ViewPlane_Rect = [-.2,-.2, 1.4,1.4] or some such thing.) In natural
coordinates maybe the following could be done:
xMin = Min(ZoomedDataX, Max = xMax)
yMin = Min(ZoomedDataY, Max = yMax)
xSpan = xMax-xMin
ySpan = yMax-yMin
oView->SetProperty, ViewPlane_Rect = [xMin-0.2*xSpan, yMin-0.2*ySpan,
oGrAtom->SetProperty, xRange = [xMin,yMin], yRange = [yMin,yMax]
oXaxis->Location = [xMin,yMin,0], Range = [xMin,xMax]
oYaxis->Location = [xMin,yMin,0], Range = [yMin,yMax]
Well, it's the holiday season, perhaps I'm having visions of sugared plums...
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