Well, why not have an animation? Example: Say you wanted to show how many miles an hour they are going (i know, it's big, you could make it smaller if you wish). Have a little circle, with the numbers, and the spindle starting at 0. Put in one animation for every time they go faster (eh, i don't believe there is mph in cs, but it's just an example). Make an event that links to the animations (if you can, i never tried). Sorry if this is buggy, I just thought it up, plus I am a newb. It also may not be the best way to do this.
Another way is to have a gauge, then to have a global. Make the global gb_speed or something. Create a keydown on up down left and right and have gb_speed increase. I forget how to make some format of the global show up on the screen, but maybe you can figure it out, or look for it in other questions.
The third way is to combine the two. Have the global be linked to the animation, along with the events/keydowns.
I'm not sure if any of these ways work, but they're worth a try. Sorry if they don't.
Hope I helped,
Bunny
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If people would take the time to understand and know someone, to appreciate this person, wouldn't we live in a better world?
But if we did, then how would we learn anything? A world without hurt is a world without lessons.