Physics Engine Requirements

If its just a over the head tile based rpg there shouldnt be to much physics. Physics are only big in 2d sidescrollers and 3d games because you have to worry about jumping, springs, etc... But for your rpg you may just have a velocity for each moveable sprite but it wouldnt really be necisary.


Brendon

as far as physics is concerned:
F=ma
F=mg
F=GmM/(R^2)
don't forget friction and normal forces, etc...
there are also vector ops if you do it in 3d...
there are integrals and derivatives if you want acceleration and
velocity and speed...
the physics can be huge...it really comes down to what effects exactly you want to implement, like Brendon says. If the engine is 3/4 down isometric or something and you want your character to jump, you may want implement gravity etc. post specifics so we can help. note also that there exist phyiscs libraries that can simplify your tasks

on a side note, realistics physics tends to ruin games

Edited by - stani on December 7, 2000 5:35:41 PM

For an RPG, the only physics I would have would be having velocities and stuff, like for running. So that when you run, you would slow down gradually as you come to a stop. Or maybe skid to a stop, or skid as you run in one direction and then try to run in the opposite direction. That is about it though.

The euation F=GmM/(R^2), posted by Stani, is NOT needed, unless you are having planets in the game and want a very realistic world, but I would just leave that out. The F=mg is only good if you guys jumping/falling, or if you want arrows to fall to ground after a while, and you actually want to see them fall.

F=ma is really only good for things hitting each other in a game. It is also used for friction though.

velocities would still require some calculus, a world-true simulation would also, among other things, have to take care of friction and gravity and momentum i guess. yes, some of my formulas are redundant, but the question is rather vague

Thanks for the info. It has helped a lot. Sorry about the question being so vague, but basically that was why I was aking. I did not really have a clue as to what to even think about for this portion of the architecture.

I have the physics background (CS grad) but I guess I just was not putting the big picture together. BTW, I will be including gravitational, force and pendulum effects. (Others may be used but I will have to determine my player''s entire range of movement and action before really nailing it down.) Thanks.





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