Difference between revisions of "Parabolic Shot"
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Revision as of 18:02, 16 December 2007
This is an small tutorial to show how make an object to follow a path given by a mathematical function as a reply for a requested tutorial.
Mathematical function to follow
We're going to simulate a cannon shot. A cannon bullet describes a parabolic trajectory after it is shot by the cannon. The mathematical equations that govern the trajectory are:
X=V0x*t+X0 Y=-0.5*G*t²+V0y*t+Y0
where:
t = the current time for the mathematical equation X = the 'x' coordinate of the bullet at a time 't' Y = the 'y' coordinate of the bullet at a time 't' X0 = the 'x' position of the bullet at time t = 0 Y0 = the 'y' position of the bullet at time t = 0 V0x = the 'x' component of the velocity when shot (t = 0) V0y = the 'y' component of the velocity when shot (t = 0) G = the gravity's acceleration.
You usually have the angle and the velocity modulus instead of its components. The decomposition is quite easy:
V0x = V0*cos(phi) V0y = V0*sin(phi)
where:
V0 = the velocity when shot (t = 0) phi = the shooting angle.
