koobas.hobune.stream
Aim helper in realistic sniper game
I'm making a sniper game with gravity and wind influence on bullet. I'm moving bullet with constant velocity in forward direction and adding physics.gravity*Time.FixedDeltatime. So if there is a target 300 units away my bullet with take 36 frames to reach it(300/velocity*Time.FixedDeltatime) which we will call predictedFrames, when i multiply predictedFrames with gravity it should give mei the y position of bullet after 36 frames but it gives me the wrong position. I did Debug.Log(physics.gravity*Time.FixedDeltatime) and it give me -0.2 which should be the gravity per frame but it's not, after the first frame bullet y position is 0.0011 something. I did everything but nothing worked. plz help
Hi @notijaz you're really close but remember that acceleration is a change in velocity, i.e. a change in distance over time, over time. predictedFrames * Time.fixedDeltaTime represents the amount of total travel time your bullet has before it reaches the target at 300 units. The equation to calculate fall distance under acceleration is:
y_fall = 0.5 * acceleration * time * time; //this is the time over time portion for distance travelled
Check this out: https://en.wikipedia.org/wiki/Equations_for_a_falling_body
And here's some (updated) code that should work for you:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class BulletController : MonoBehaviour
{
float initial_velocity = 417f;
float distance_to_target = 300f;
float time_to_target;
int predictedFrames;
float bullet_drop;
Vector3 bulletvelocity;
// Start is called before the first frame update
void Start()
{
bulletvelocity = initial_velocity * (transform.rotation * new Vector3(1, 0, 0)); // +x velocity
Debug.Log(bulletvelocity);
time_to_target = distance_to_target / initial_velocity;
Debug.Log("Time to reach target: " + time_to_target);
predictedFrames = (int) ((distance_to_target / initial_velocity) / Time.fixedDeltaTime);
Debug.Log("Frames to reach target: " + predictedFrames);
bullet_drop = -Physics.gravity.y * 0.5f * time_to_target * time_to_target;
Debug.Log("Distance to drop: " + bullet_drop);
bullet_drop = -Physics.gravity.y * 0.5f * predictedFrames * Time.fixedDeltaTime * predictedFrames * Time.fixedDeltaTime;
Debug.Log("Distance to drop: " + bullet_drop);
Debug.Log(Physics.gravity);
}
// Update is called once per frame
void FixedUpdate()
{
bulletvelocity += Physics.gravity * Time.fixedDeltaTime;
transform.position += bulletvelocity * Time.fixedDeltaTime;
}
}
Just a note, when converting float back to int using (int), it rounds down I think. So when you calculate predictedFrames make sure to round up your float first, that way your calculation isn't missing frames. Or you can have your predictedFrames be a float and your calculations will work fine.
Thank you sir for your time.I will implement this later and will let you know
sorry sir but there is one problem I'm not using rigidbody. $$anonymous$$y code looks like
void start()
{
bulletvelocity=transform.forward*speed;
point1=transform. position;
}
void update()
{
bulletvelocity+=physics.gravity *Time.FixedDeltatime;
point2=point1+bulletvelocity* Time.FixedDeltatime ;
//raycast stuff for checking hit
point1=point2;
transform.position =point1;
}
No worries - just change rigidbody.velocity calls to your bulletvelocity. I've updated my answer to show that.
thank you sir. I'll let you know when i implement it later
