The first speed calculated ball does not go to the target it should go

Question

In the function below, The distance between ball and target is known(R). Also, the angle between the resultant vector and the x-axis is known(LaunchAngle). Thanks to these parameters(R, LaunchAngle), I calculate the initial velocity of a ball. I checked all the values. According to physics, they are all correct. Although all calculations are correct, the ball does not hit the target.

void LaunchFromTargetPositionWithoutFrictionForce()
        {
            Vector3 projectileXZPos = new Vector3(transform.position.x, 0.0f, transform.position.z);
            Vector3 targetXZPos = new Vector3(TargetObjectTF.position.x, 0.0f, TargetObjectTF.position.z);
            transform.LookAt(targetXZPos);

            float R = Vector3.Distance(projectileXZPos, targetXZPos);
            float G = -Physics.gravity.y;

            float Vz = Mathf.Sqrt(G * R / Mathf.Sin((2.0f * LaunchAngle) * Mathf.Deg2Rad));
            float Vy = Vz * Mathf.Sin(LaunchAngle * Mathf.Deg2Rad);
            float Vx = Vz * Mathf.Cos(LaunchAngle * Mathf.Deg2Rad);
            text2.text = "vz: " + Vz.ToString() + " vy: " + Vy.ToString() + " vx: " + Vx.ToString();

            Vector3 localVelocity = new Vector3(0f, Vy, Vx);
            Vector3 globalVelocity = transform.TransformDirection(localVelocity);


            rigid.velocity = globalVelocity;
            bTargetReady = true;

            if (isSlowMotion) timeManager.slowMotion();
        }

First location of the ball

And after 2-dimensional motion it is hit before target

maybe i understand it wrong, but it seems like the target is on course? does it stop befor the target? is there a collider that is to big? — nkazz, Feb 14 '20 at 07:22
according to the angle, sometimes it stops before the target, sometimes after the target, and sometimes stops on exact target. But it should stop on target every time. There is a collider. — Ayşe Betül Şimşek, Feb 14 '20 at 08:03
does rigidbody using diffrent physics? According to the physic calculations it should hit target every time. But it hits somewhere else what i calculated?? — Ayşe Betül Şimşek, Feb 14 '20 at 08:11
What is the difference between stop points on axis ? Like sometimes it stops at 10.000134f and sometimes it stops at 10.000256f ? Numbers are just example but what I've experienced is dealing with precision is hard. Maybe try to fix the positions and numbers to .00f that might help — Thalthanas, Feb 14 '20 at 08:19

score 0 · Accepted Answer · answered Feb 14 '20 at 09:40

I changed first 3 line with below codes. And problem solved.

    Vector3 projectileXZPos = transform.position;
    Vector3 targetXZPos = TargetObjectTF.position;
    float dist = Vector3.Distance(projectileXZPos, targetXZPos);
    transform.LookAt(targetXZPos);

The first speed calculated ball does not go to the target it should go

1 Answers1