I have a game where a bullet affects a physics object. I apply an impulse via a vector from the bullet to the object-with a multiplier, for whatever reason, the result from the editor/debugging is amplified vs the packaged game. For example, when testing in the editor the object will move 100 meters, in game it will move 10. Am I insane? The packaged game is noticeably weaker. If I increase the multiplier it DOES increase the result/power but there is a drastic difference between compiled vs. debugging + editor. I have attached the function at hand, Sadly it wouldn’t be practical to attach the whole game.
Bump a lump
The problem with “add force” is that it’s highly dependent on the step time. If your packaged game runs at a higher frame rate, the force will be applied over a shorter time span, and thus will impart a smaller impulse.
A better option is to add an impulse, which is an instantaneous packet of “force times time.”
And, an even more robust (but less physical) option is to apply the impulse as “velocity change” rather than force-time. Specifically, the impulse will be divided out by the mass of the target, whereas a “velocity change” won’t depend on the mass of the target.
Ah that is exactly what is happening THANK YOU.
To tell you the truth? Experience with physics engines. Not sure that there’s a great way to quickly learn everything there is to know about game physics (or rendering, or networking, or gameplay systems, or character animation, or …) Get ahold of it, use it in anger, talk to other people doing the same thing (GDC, for all its faults, is good for this.)
While Unreal is of course its own lifestyle, and not all experience transfers between engines, some basics are the same because the problem they solve is the same.
I’ll take “walls of text” over video tutorials that just show you buttons to click, any day of the week! Text can be searched with ctrl-F. Text can easily be scrolled back precisely if you miss something. Text is easy to zero in on with Google. At times, the text is not enough, and reading the source is the next step, but I think the Unreal text is much better than many other engines I’ve worked with.
In fact, the parts I miss are the parts that don’t have text; where the documentation for some member [FONT=Courier New]bUseAlternateMethod is simply “Use Alternate Method” and I have no idea what this means without searching the code.