How could we curve a ball in a football kick going from source to destination?

I have tweened the ball from one point to other.

if(this.kick == false) return;

if (this.val > 1) return;

this.val += dt;
var target = KickFootball.v1;
target.lerp(this.src, this.des, this.ease( this.val ));

Hi @yash_mehrotra,

If you aren’t using physics you will have to use some equation to calculate that trajectory.

And these two things come to my mind that may be of help:


You can also find a maxima of the curve, say 2 meters to the side of a straight path which is from point A to point B.

You can find that normal by using a cross product of the path direction (from A to B) and an up vector (pc.Vec3.UP or pc.Vec3.DOWN, depending on whether you want go left or right from the path). Since we want 2 meters, we multiply the final vector by 2 and then lerp and add it to the target (just lerp it twice as fast, so that it would reach its maxima in the middle of the path, for example)

const offset = new pc.Vec3();

const pathDirection = endPoint.clone().sub(startPoint).normalize();
const side = new pc.Vec3().cross(pathDirection, pc.Vec3.UP).mulScalar(2);
const val = this.ease( this.val );

target.lerp(this.src, this.des, val);
// lerp from zero to 1, then back from 1 to zero
offset.lerp(pc.Vec3.ZERO, side, val < 0.5 ? val * 2 : 1 - (val * 2 - 1); 


P.S. I typed here, so could be typos in the code, but you should get the idea.

Oh you would need the appropriate easing function, so the curve looks alright (not a linear one at least). You can test some variants to see what matches your case.