Path: utzoo!utgpu!watmath!watcgl!jdchrist
From: jdchrist@watcgl.waterloo.edu (Dan Christensen)
Newsgroups: comp.sys.sgi
Subject: why is getmatrix() so slow?  where is it called?
Keywords: getmatrix
Message-ID: <9607@watcgl.waterloo.edu>
Date: 9 May 89 20:09:18 GMT
Distribution: comp
Organization: U of Waterloo, Ontario
Lines: 21

I have a program that repeatedly draws roughly 3000 polygons and updates
the matrix stack.  I did a profile of its execution.  The top few lines I
received are:

%time     seconds  cum %   cum sec  procedure (file)

 30.7      7.7400   30.7      7.74 normal (normal.c)
 29.8      7.5200   60.5     15.26 solidicos80 (spheres.c)
 13.1      3.3100   73.7     18.57 gl_getmatrix (getmatrix.c)
  4.9      1.2400   78.6     19.81 v3f (sgl2.s)

This is on an Iris 4D/120GTX running release 3.1C.  In no place do I call
getmatrix.  Why is it getting called and how come it is occupying the
processor over 13% of the time?  Note that normal and v3f are called
roughly 9000 times for every time the matrix stack is updated.

Thanks for any help.

----
Dan Christensen, Computer Graphics Lab,	         jdchrist@watcgl.uwaterloo.ca
University of Waterloo, Waterloo, Ont.	         jdchrist@watcgl.waterloo.edu