Implementing Projectile Motion

Question

I\'ve scored the internet for sources and have found a lot of useful information, but they are math sites trying to tell me how to solve what angle an object has to be at to

Answer 1

Don't use the equations for position. Instead, use the equations for velocity. Calculate the new velocity each loop of your simulation from the object's old velocity and apply it to your object. You will need to know the elapsed time between each loop of the simulation. Of course, this works for vertical or horizontal velocity.

v_new = v_old + acceleration * delta_time  (from wikipedia)

Then apply:

position_new = position_old + v_new * delta_time;

You can use a simple acceleration of -9.8 m/s (don't forget that "down" on the screen is really an increase in the vertical position! So you can use +9.8 for simplicity). Or you could get fancy and add variable acceleration (for example, from wind, if you are also modeling the horizontal motion of the object).

Basically, the acceleration you apply is based on the sum of forces applied to the object (force of gravity, friction, jet propulsion, etc.).

F_final = F1 + F2 + ... + Fn

The following can help you with that.

If you are modeling a force applied to the object, first break the force into it's horizontal and vertical components using:

F_horiz = F * sin( angle )
F_vert =  F * cos( angle )  where angle is the angle between the force and the horizontal.

Then calculate the acceleration from the force using:

a = F / mass

(I give all credit for this knowledge to my first programming experience: GORILLA.BAS =) )