Well today I hit a milestone in the development of my engine; the core engine is done and now I simply need a huge list of user-end functions to add to it. I already have plenty of ideas, but I think that asking the community will result in more ideas. Besides I created this project with the idea in mind that it would be used by others. I think that a new age of WC3 mapping that includes heavy use of physics is possible now.
FAQ:
What does the engine do?
-- It allows you to create spheres that bounce off the ground and each other realistically. It also allows you to create particles with no collision.
-- It allows you to create and control these objects using an an extremely user friendly syntax.
-- It allows you to specify individual object parameters such as friction, acceleration, etc.
-- It allows you to execute functions based on events such as an object bouncing, colliding with another object, dying, or killing something.
Why would you want to create spheres?
-- Spheres can approximate anything. Turn your heroes into spheres and now they will get shoved back when running into other objects, run up hills more slowly and down them more quickly, fall off of cliffs, and making them perform realistic jumps is as simple as issuing 1 line of code. Turn your fireballs, bullets, and other missiles into tiny spheres for realistic projectile behavior. Make your explosions knock stuff back and create whirlwinds that pick stuff up and throw it. Create bowling, pool, basketball minigames.
Sounds great, but isn't that the same thing as previous engines?
-- No, this is the first engine to support collision between objects, rolling objecs, and many other features. It is also the first to take advantage of the new object-oriented JASS and all of its advantages (yes, preprocessor is required).
OK, but isn't it laggy with all those extra features?
-- No, in fact it is less laggy by a magnitude of 10 due to the extremely optimized way in which it is written. On my computer (decently fast) and optimized with Vexorian's map optimizer, the engine can handle the maximum number of collision objects (about 250) without lagging. Non-collision objects have no limit on their number and also have virtually zero performance cost, so you could go well above 500 with a combination of collision and non-collision objects. The point is that this engine is fast enough that virtually every moving object in your map can be included in it if you so wish.
What's the syntax look like?
I am deleting this because the syntax changed
Some current features (not all):
Fully configurable performance options
Multisampling so that tiny, fast moving objects collide correctly
Automatically detects map bounds, but also accepts user-defined bounds
Mass (affects collisions between objects)
Friction
Drag
Gravity
Speed limit for individual objects
Easy option to accelerate in a unit's facing direction
Execute functions upon bouncing, colliding, death, and killing
Use GetObject(unit) to get the object associated with a unit
Objects can be removed and are cleaned up completely
object.forEach method to execute a function easily for every object
Some basic impulse commands (specify x, y, z force or distance, angle, angle)
Some basic acceleration commands (specify x, y, z force or distance, angle, angle)
Pause and resume engine
Struct-based object profiles for easy creation of objects
Some planned features:
Scalable objects
A function to knock units back within range of a point (useful for that fireball)
Max number of bounces for an object
Suite of commands for handling projectiles
Z-axis tilting for projectiles (thanks to vex's model)
"Gravitators," objects that pull other objects toward them like gravity
Objects can kick up tile-based dust
Static (non moving, but collidable) and particle (moving, but non colliding) objects
Tornado sample function
User suggested features:
maybe switch to interfaces (Vexorian)
enters/leaves quad events (Jazradel/Vexorian)
command to make objects orbit around other objects (Fulla)
When I get any cool suggestions that I like, I will add them to that last section along with credit for the idea. So feel free to ask any questions about the engine or make suggestions for features.
Attached is a test version, optimized with Vex's map optimizer. I don't want to release a usable version until it's done, but there's no point asking for feedback unless you can try it out. Remember that you can select the balls and control them by clicking... you can control it, not just watch it.
NOTICE: Don't run this from the editor if you use Grimoire, it will lag very badly because of Grimoire's error checking. Run it from WC3 instead.
NEW UPDATE: Better integration method, dynamically changable time step, fixed acceleration issue (default gravity is -1000 now, not -30), improved performance. | 
JASS: