[Plib-cvs] plib/doc/ssgAux index.html,1.9,1.10

[Steve B. <sj...@us...>]

Update of /cvsroot/plib/plib/doc/ssgAux
In directory usw-pr-cvs1:/tmp/cvs-serv11522/plib/doc/ssgAux

Modified Files:
	index.html 
Log Message:
Allow setting of each particle's size individually - and
also fix bug to *center* each particle around it's position.


Index: index.html
===================================================================
RCS file: /cvsroot/plib/plib/doc/ssgAux/index.html,v
retrieving revision 1.9
retrieving revision 1.10
diff -u -d -r1.9 -r1.10
--- index.html	24 Aug 2002 20:36:20 -0000	1.9
+++ index.html	27 Aug 2002 22:29:20 -0000	1.10
@@ -368,6 +368,7 @@
   sgVec3 vel ;
   sgVec3 acc ;
  
+  float size ;
   float time_to_live ;
   void *userData ;
  
@@ -429,7 +430,8 @@
 this particle was last updated.
 <p>
 The callbacks can set, read or change any or all aspects of the particle...
-it's colour, position, velocity, accelleration and 'time to live' (in seconds).
+it's colour, position, velocity, accelleration, size and 'time to live'
+(in seconds).
 There is also a user data pointer - so you can hang your own data onto
 each individual particle.
 <p>
@@ -505,9 +507,13 @@
 running the explosion particle system when all the pieces have landed
 and 'gone away'.
 <p>
-All the particles have to be the same size - but you can use
-the 'setSize' function to change their size on-the-fly - for example
-to make a cloud of bubbles that grow over time.
+The size of each particle is the size field of the individual particle
+MULTIPLIED by the number you pass into the size parameter of the
+ssgaParticleSystem constructor (or set with setSize()).  This allows you
+to cheaply set the particle size for all the particles at once - or to
+tweak the size of each one in turn.  The number in the particle structure
+defaults to 1.0 so you can ignore it and just set the size in the
+particle system overall.
 <p>
 ssgaParticleSystem is derived from ssgVtxArray - so you can apply textures and
 other state things using the usual ssgVtxArray::setState(ssgSimpleState*)