Question

i have a ball which i have to drop from a height and it should behave as it behave in the real world mean it should drop with g=9.8 and also bounce back.can any one tell me how i can do it in open gl in c++?

Answer 1

OpenGL is only for drawing 3D graphics, it knows nothing of concepts like speed, mass, velocity, time, acceleration and gravity (or rhubarb pie calorie count, for that matter).

You need a physics engine, or a simple physics simulation:

The simple per-frame loop goes something like this:

• dt = time_now – time_prev_frame
• acc = -9.8
• vel += acc * dt
• pos += vel * dt
• draw object at pos

That being said, there are people who implement particle systems using OpenGL GPUs for simulation, but then adapt the graphics concepts, primitives & calculations to compute positions and velocities by implementing the physics equations themselves..