OpenSceneGraph/src/osgText
Robert Osfield 22eae68e48 From Mathias Froehlich, "This is a generic optimization that does not depend on any cpu or instruction
set.

The optimization is based on the observation that matrix matrix multiplication
with a dense matrix 4x4 is 4^3 Operations whereas multiplication with a
transform, or scale matrix is only 4^2 operations. Which is a gain of a
*FACTOR*4* for these special cases.
The change implements these special cases, provides a unit test for these
implementation and converts uses of the expensiver dense matrix matrix
routine with the specialized versions.

Depending on the transform nodes in the scenegraph this change gives a
noticable improovement.
For example the osgforest code using the MatrixTransform is about 20% slower
than the same codepath using the PositionAttitudeTransform instead of the
MatrixTransform with this patch applied.

If I remember right, the sse type optimizations did *not* provide a factor 4
improovement. Also these changes are totally independent of any cpu or
instruction set architecture. So I would prefer to have this current kind of
change instead of some hand coded and cpu dependent assembly stuff. If we
need that hand tuned stuff, these can go on top of this changes which must
provide than hand optimized additional variants for the specialized versions
to give a even better result in the end.

An other change included here is a change to rotation matrix from quaterion
code. There is a sqrt call which couold be optimized away. Since we divide in
effect by sqrt(length)*sqrt(length) which is just length ...
"
2008-09-17 16:14:28 +00:00
..
CMakeLists.txt Reverted the changes for ill fated tweaks for Apple build 2008-04-24 11:34:43 +00:00
DefaultFont.cpp From Sid Byce, fixes for compiling with gcc 4.3 2007-12-24 15:19:52 +00:00
DefaultFont.h Convert osgText and freetype plugin across to keeping the font size as state that 2007-12-23 18:15:54 +00:00
FadeText.cpp Set the DataVariance on FadeText to DYNAMIC to reflect their nature 2008-07-03 10:03:06 +00:00
Font3D.cpp Refactored the mutex usage in osgText and freetype plugin to prevent multi-thread crash 2008-02-25 12:54:54 +00:00
Font.cpp From Sherman Wilcox with a little reorganisation from Robert Osfield, added 2008-03-29 09:59:23 +00:00
String.cpp From Roland Smeenk, "Attached you will find a large set of small typo fixes (mainly in the comments)." 2007-12-10 17:30:18 +00:00
Text3D.cpp From Mathias Froehlich, "This is a generic optimization that does not depend on any cpu or instruction 2008-09-17 16:14:28 +00:00
Text.cpp From Mathias Froehlich, "This is a generic optimization that does not depend on any cpu or instruction 2008-09-17 16:14:28 +00:00
TextBase.cpp Added provisional block in computePositions() 2008-08-26 09:39:45 +00:00
Version.cpp Unified the setup of version numbers so that they all are based on the version 2007-04-22 20:19:43 +00:00