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Object rendering with dynamic views


I am wondering about the best way to manage objects graphics
when the display consists of changing and unchanging
models.  I have done it three different ways in the past,
but I never considered the merits of each (until now.)

(1) The first way is that outlined in the online manual
(also David has a nice page about this.)  This method
involves just one view.   The view is first rendered with
the static portion of the graphics exposed and the dynamic
parts hidden using :
 myDraw->DRAW, myView, /Create_Instance
Then the view is made transparent, the static portion is
hidden and the dynamic portion is exposed.  After that the
view is drawn using:
 myDraw->DRAW, myView, /Draw_Instance
Any subsequent changes in the dynamic atoms/models are
rendered using the DRAW_INSTANCE keyword.

(2) The second way is to create two overlapping views, the
static underneath and the dynamic on top with the
TRANSPARENT keyword set.   Then draw each view using the
CREATE_INSTANCE and DRAW_INSTANCE keywords as needed.   This
is a method discussed (a long time ago) on the newsgroup,
but I can't find it documented anywhere.

(3) Put all the atoms/models in one view and render the
whole thing as one.   Grind-grind-grind.   I use this method
when in a hurry to write code, but I really don't want to
look at it.

Can someone explain the relative merits/pitfalls of each of
the methods (in particular the first two?)  I come to this
because I have routine to that tracks
a scatter plot.  When the cursor passes over a target atom,
information about that datum is displayed and, like
Pavloff's dog, the operator starts to drool.  (Just kidding,
so far no information is displayed.)



Ben Tupper
248 Lower Round Pond Road
POB 106
Bristol, ME 04539

Tel: (207) 563-1048
Email: PemaquidRiver@tidewater.net