Ammo.js - basketball game, make a shot successfully - AKA motion trajectory

Questions
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2

Solved it!

OK, three things:

  1. The rotation of the velocity wasn’t working. Used atan2 instead.
  2. I needed to switch the subtracting Y axes points getting the yOffset
  3. I needed to use .setVelocity(x, y, z) instead of .applyForce(x, y, z)

Here is the final script, hope it helps someone!

static getBallVelocity( ballPos, rimPos, angleDegrees, gravity ){
 
  // Get angle in radians, from angleDegrees argument
  const angle = THREE.Math.degToRad( angleDegrees );
 
  gravity = gravity || 9.81;
 
  // Positions of this object and the target on the same plane
  const planarRimPos  = new THREE.Vector3( rimPos.x, 0, rimPos.z ),
        planarBallPos = new THREE.Vector3( ballPos.x, 0, ballPos.z );
 
  // Planar distance between objects
  const distance = planarRimPos.distanceTo( planarBallPos );
 
  // Distance along the y axis between objects
  const yOffset = ballPos.y - rimPos.y;
 
  // Calculate velocity
  const initialVelocity = ( 1 / Math.cos( angle ) ) * Math.sqrt( ( 0.5 * gravity * Math.pow( distance, 2 ) ) / ( distance * Math.tan( angle ) + yOffset ) ),
        velocity = new THREE.Vector3( 0, initialVelocity * Math.sin( angle ), initialVelocity * Math.cos( angle ) );
   
  // Rotate our velocity to match the direction between the two objects
  const dy = planarRimPos.x - planarBallPos.x,
        dx = planarRimPos.z - planarBallPos.z,
        theta = Math.atan2( dy, dx ),
        finalVelocity = velocity.applyAxisAngle( PopAShotAR.Vector3.up, theta )
 
  return finalVelocity;
}
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