I want to calculate the force of the collision. For example, the car is on the bridge, and I want to find
pressure force. In the second case, I have a falling car, and I want to find the force of the impact. Are there any functions for this?
I want to use c ++.
All you do is multiply the Mass and the Speed together
void AMyActor::OnHit(UPrimitiveComponent* HitComp, AActor* OtherActor, UPrimitiveComponent* OtherComp, FVector NormalImpulse, const FHitResult& Hit)
{
float HitForce = OtherActor->GetVelocity.Size() * OtherComp->GetMass();
UE_LOG(LogTemp, Warning, TEXT(HitForce));
}
HitForce is the variable you're looking for.
Related
I've been trying to understand NeRF. I finished reading the paper(Tancik) and watched some of the videos. I have been looking at some parts of the code. However, I can't quite wrap my head around what the get_rays function does in terms of the code. Could anybody just run through line-by-line about what each line in the the get_rays function is supposed to do?
def get_rays(H,W , focal, c2w): #c2w is pose
i, j = tf.meshgrid(tf.range(W, dtype=tf.float32), tf.range(H, dtype=tf.float32), indexing='xy')
dirs = tf.stack([(i-W*.5)/focal, -(j-H*.5)/focal, -tf.ones_like(i)], -1)
rays_d = tf.reduce_sum(dirs[..., np.newaxis, :] * c2w[:3,:3], -1)
rays_o = tf.broadcast_to(c2w[:3,-1], tf.shape(rays_d))
return rays_o, rays_d
It creates two lists, rays_o represents points where rays originate (camera centre) and rays_d represents direction vectors of each ray casting through the centre of every pixel of the camera. In this case, all values in the rays_o are the same because the function gets rays from a single camera.
Basically I am creating a game that spawns a ball after a certain amount of time has passed. However, as time goes on and the player score increases, balls that are more difficult to kill will spawn.
Prior to this, all the spawn methods I have set in place function as I would like them to, but they were contained in a switch statement that calculated the probability a ball would spawn.
//pseudo:
let spawnProbability = arc4random_uniform(100)
switch spawnProbability {
case 0…60: //60% spawn chance
//spawn small ball
case 61…90: //~30% spawn chance
//spawn medium ball
case 91…100: //~9% chance
//spawn large ball
default:
break
}
This worked as a plan B, but I'd like to implement what I originally had designed which was the method described above.
My thought process to accomplish what I originally had in mind is:
for loop that spawns small balls until the score counter reached a certain amount
after the score counter reached, say, 100pts, another for loop would be executed in addition to the first loop. So, medium and small balls spawn after a delay.
after the score counter reached another mark, large balls would begin to spawn on top of medium balls and small balls.
Here's what I mean: (pseudocode again)
for(var i = 0; i < 10; i++) {
//delay
//spawn small ball
}
if score >= 100 {
for (var x = 0; x < 10; x++) {
//delay
//spawn medium ball
}
}
// . . . and so on
I've put alot of thought into how I could accomplish what I want but I can't come up with a better approach to this problem. I understand why this isn't working and why multiple for loops can't be executed with delay in the same class at the same time (or maybe they can and I'm just going about it in the wrong way) but I'm stuck in the sense that I don't know a better way to implement the spawn technique that I want.. Any help is greatly appreciated!!
I am working on Unity2d Sprite but something is wrong: in my code when I press the jump button my character jump like teleport, it go very fast in the Up direction. The gravity is 9 and my Rigidbody2D mass is 1. My code is this:
if(isGrounded == true && moveH == 0) {
if (Input.GetKeyDown(KeyCode.J)) {
anim.SetBool("str_jump", true);
//rgBody.velocity = new Vector2(0,jumpHeight);
//rgBody.AddForce(Vector2.up * jumpHeight);
transform.position = new Vector2(transform.position.x,
transform.position.y * jumpHeight);
isGrounded = false;
}
}
If your jump is too high, you have to use a variable to modify the height of the jump. In your case, you are using the jumpHeight as the variable to modify the height of your jump.
Decreasing jumpHeight should solve your problem. Note that if jumpHeight is declared as public (public float jumpHeight;), you have to change the variable from the Editor or a function because it will not use the number assigned to it when it was declared. It will use whatever that is assigned to it from the Editor.
For example, when you have public float jumpHeight = 4; but the value is set to 0 in the editor, 0 will be used as the value not 4.
Also you have to use rgBody.AddForce(Vector2.up * jumpHeight);. Uncomment it and then remove the transform.position = new Vector2(transform.position.x,transform.position.y *jumpHeight); line of code.
If this does not solve your problem, then you have to update your question with your complete code.
For a nice jump you could also use rgBody.AddForce((Vector2.up * jumpHeight), ForceMode2D.Impulse); It simulates an impact on your object and you get a nice jump simulation.
Do not forget to declare the public float jumpHeigt = 4f; like "Programmer" said it before.
I hope it will help you.
Simply reducing the jumpHeight value will fix the initial issue of the jump being too high.
However if you want a more realistic 'jump' you may want to utilise Rigidbody2D.velocity simply having rgBody.velocity = new Vector2(rgBody.velocity.x, jumpHeight); should create a nice smooth jump.
If you use the Rigidbody2D.velocity instead of simply changing the transform means that you can alter values such as Gravity Scale and this will make a noticeable difference on the movement of your player. You can play around with different jumpHeight and Gravity Scale values to find what works best for your game.
Use transform.position '+=' instead of just '='. This way you're adding to it's position and not setting it to a certain number(that's why it's teleporting like that). Tho this method only suits horizontal movement in my opinion(if it's a sideview game). For jumping, using AddForce would be way better.
Right now I have 2 Cameras: the main camera displays the gun at its normal state and a second camera is attached to the gun (the gun is a child of the main camera) and when toggled it looks through the scope of the gun and increases the field of view.
Heres a visual for a better understanding:
Now if I were to just toggle the second camera on and turn the main camera off, this would work splendid, but it's not very ideal. You should only have 1 camera per scene.
So I want to Lerp the position of the camera to look through the scope and manually decrease the fieldofview. So I have written the following script:
[RequireComponent(typeof(Camera))]
public class Zoom : MonoBehaviour {
private Transform CameraTransform = null;
public Transform ZoomedTransform;
private bool zoomed = false;
void Start () {
CameraTransform = Camera.main.transform;
}
// Update is called once per frame
void Update () {
if (Input.GetKey (KeyCode.LeftShift))
{
CameraTransform.position = Vector3.Lerp (
CameraTransform.position,
CameraTransform.position + ZoomedTransform.position,
5f * Time.deltaTime
);
CameraTransform.Rotate(ZoomedTransform.rotation.eulerAngles);
}
}
}
The problem with this is that it doesn't work: when I hit the zoom button, the camera speeds through the scene at the speed of light and it's hard to tell exactly what is going on.
Could anyone give me some insight as to what I'm doing wrong? I think it is something to do with the parent-child relationship, but even when I've tried using static values, I cannot seem to replicate the correct solution.
Hierarchy:
(This answer operates under the assumption that ZoomedTransform is a relative transformation, and not the absolute position of the camera as suspected by 31eee384's answer.)
I think there are a couple issues with your code. I'll tackle them individually so they're easier to understand, but they both relate to the following line:
CameraTransform.position = Vector3.Lerp (CameraTransform.position, CameraTransform.position + ZoomedTransform.position, 5f * Time.deltaTime);
First, let's look at how you're using Vector3.Lerp(). For the third argument of Vector3.Lerp(), you're supplying 5f * Time.deltaTime. What exactly does this value work out to? Well, the standard framerate is about 60 FPS, so Time.deltaTime = ~1/60. Hence, 5f * Time.deltaTime = 5/60 = ~0.0833.
What is Vector3.Lerp() expecting for the third argument, though? According to the documentation, that third argument should be between 0 and 1, and determines whether the returned Vector3 should be closer to the first or second given Vector3. So yes, 5f * Time.deltaTime falls within this range, but no interpolation will occur - because it will always be around ~0.0833, rather than progressing from 0 to 1 (or 1 to 0). Each frame, you're basically always getting back cameraPos + zoomTransform * 0.0833.
The other notable problem is how you're updating the value of CameraTransform.position every frame, but then using that new (increased) value as an argument for Vector3.Lerp() the next frame. (This is a bit like doing int i = i + 1; in a loop.) This is the reason why your camera is flying across the map so fast. Here is what is happening each frame, using the hypothetical result of your Vector3.Lerp() that I calculated earlier (pseudocode):
// Frame 1
cameraPosFrame_1 = cameraPosFrame_0 + zoomTransform * 0.0833;
// Frame 2
cameraPosFrame_2 = cameraPosFrame_1 + zoomTransform * 0.0833;
// Frame 3
cameraPosFrame_3 = cameraPosFrame_2 + zoomTransform * 0.0833;
// etc...
Every frame, zoomTransform * 0.0833 gets added to the camera's position. Which ends up being a really, really fast, and non-stop increase in value - so your camera flies across the map.
One way to address these problems is to have variables that stores your camera's initial local position, zoom progress, and speed of zoom. This way, we never lose the original position of the camera, and we can both keep track of how far the zoom has progressed and when to stop it.
[RequireComponent(typeof(Camera))]
public class Zoom : MonoBehaviour {
private Transform CameraTransform = null;
public Transform ZoomedTransform;
private Vector3 startLocalPos;
private float zoomProgress = 0;
private float zoomLength = 2; // Number of seconds zoom will take
private bool zoomed = false;
void Start () {
CameraTransform = Camera.main.transform;
startLocalPos = CameraTransform.localPosition;
}
// Update is called once per frame
void Update () {
if (Input.GetKey (KeyCode.LeftShift))
{
zoomProgress += Time.deltaTime;
CameraTransform.localPosition = Vector3.Lerp (startLocalPos, startLocalPos + ZoomedTransform.position, zoomProgress / zoomLength);
CameraTransform.Rotate(ZoomedTransform.rotation.eulerAngles);
}
}
}
Hope this helps! Let me know if you have any questions. This answer does ramble a little, so I hope you don't have any trouble getting the important points from it.
Your lerp target is relative to the camera's current position, so it's constantly moving. This is the target you have:
CameraTransform.position + ZoomedTransform.position
This means that as your camera moves to get closer to this position, the camera's new position causes the destination to change. So your camera keeps moving forever.
Your destination should be ZoomedTransform.position. No addition is necessary because position is in world coordinates. (And when you actually need to convert between spaces, check out TransformPoint and similar methods.)
It has been a while since I have done anything in Unity, but I think it is processing the Lerp function at frame time and not at actual time. You will need to call it in another function that is not being processed at frame time.
I'm trying to write an object oriented program (as a learning exercise, I know there may be simpler ways to do it) in which beads bounce around a 2D plane bounded by a ring. Each bead is an object defined by a class ball. In setting the initial positions of the balls I need to check that no other ball has already been placed at the same x and y coordinates.
#Class for the beads
class ball:
NumbBalls = 0
#Constructor
def __init__(self,Beads):
self.ball = sphere(pos = vector(0,0,0), radius = radiusBall,color=color.red)
ball.NumbBalls += 1
self.ball.pos = self.createInitialPosition(Beads)
#Assign ball its initial position
def createInitialPosition(self,other):
#CODE to compare self.ball.pos and other.ball.pos which returns a unique position coordinate
#Main program
NumbBeads = 100
Beads = []#Create empty list for all the beads
#create balls in random initial positions
Beads = [ball(Beads) for item in range(NumbBeads)]
I can get this to work if I create two objects bead1 and bead2 and then pass bead1 and bead2 as arguments ie bead2 = ball(bead1) but how do I do this if I am generating a list of beads and want all of them to be compared with self. Hopefully that makes sense.
Perhaps rather than the approach you are currently taking, you should consider something along these lines (of course, with the necessary changes to your class definition/methods):
N = 100
initialPositions = []
while len(initialPositions) <= N:
newPosition = generateRandomPosition()
if newPosition in initialPositions:
pass
else:
initialPositions.append(newPosition)
ballList = [ ball(p) for p in initialPositions ]
In other words, generate a list of initial positions outside of the creation of your objects, and do whatever validation/restriction you need during that creation. Then just create your objects from that list. If N is really large, you might want to consider a dictionary (or a mutable set of some sort) instead of a list for initialPositions, to help speed up the membership testing, but it's still the same concept...