Particle System API
by David McAllister
version 1.11
February 2, 1999 (Groundhog Day)
http://www.cs.unc.edu/~davemc/Particle

Running the PSpray Demo

To run the PSpray demo, click on pspray.exe and the demo will start by
drawing a fountain. It uses motion blur, which may be faster or slower
than no motion blur. To toggle it, press 'm'. Press the right mouse
button to see a menu of options. Many different particle effects are
included in the demo. The menu tells what they are. Press the space
bar to cause an explosion. Press 'f' to toggle full screen mode.

By default, the program runs a maximum of 10000 particles. Use '+' and
'-' to change the number of particles. I have a 400 MHz Pentium ][ and
it can run at about 20 frames per second with 10000 particles. That's
using an Evans & Sutherland RealImage1000 graphics card, which doesn't
have a geometry accelerator. If you have a geometry accelerator, I bet
you could do twice as many particles because the particle system code
does less work per particle than OpenGL does.

This demo shows just particles by themselves, instead of as a special
effect in an environment, but these effects can trivially be added to
any OpenGL program.

Compiling the Library for UNIX

The sample Makefile compiles both libparticle.a and pspray. If the
supplied optimization flags don't make sense, feel free to rip them
out. I've also included an SGI N32 compiled library and application.

Compiling the Library for Evil Windows

The particle library, particle.lib, comes precompiled in release
mode. If you want to recompile the library (to modify it, say), create
a new Win32 Static Library project called Particle in Visual Studio
and add all the .cpp and .h files to the project, except
pspray.cpp. Then just compile it. I've included particle.dsp, which is
a sample project file. You can try just adding it to your workspace
instead of making a new project.

Compiling the Demo for Evil Windows

Make a new Win32 Console Application project called PSpray. Make it
depend on the project Particle. Add pspray.cpp to the project. In the
C++ setting, add the particle system library folder to the include
path, and GLUT if necessary. Then in Link settings, add particle.lib,
glut32.lib, glu32.lib, and opengl32.lib. Or you can alternatively use
the SGI libraries (same names but without the 32).

That's really it. If you have any questions, comments, or suggestions
you can mail me at davemc@cs.unc.edu

Changes in Version 1.11

Fixed amount of bouncing to be independent of area of triangle or
plane. I had forgotten to normalize the plane normal. Oops.