I have a infinite vertical scrolling bar in unity and I want to suddenly limit the scrolling (in one direction only) when reaching a (variable) threshold.
public GameObject MyScrollRectContent;
public float limit = 300;
void Update () {
if(MyScrollRectContent.transform.localPosition.y >= limit){
//make it ONLY possible to scroll backwards or not beyond the limit and stop elasticity
}
Any ideas how to limit the infinite scrolling?
The simplest thing would be to use the existing ScrollRect. It allows scroll in a defined rectangle. You would have to simulate infinity by setting a really big size in one direction, or find a way to seamlessly reset the position if the user goes too far (difficult to do without seeing the jump but might be possible depending on your content).
If this is not an acceptable solution:
To limit the scrolling, you can just set the position to the limit if the user goes too high:
void Update ()
{
if(MyScrollRectContent.transform.localPosition.y >= limit)
{
var currentPos = MyScrollRectContent.transform.localPosition;
MyScrollRectContent.transform.localPosition = new Vector3(currentPos.x, limit, currentPos.z);
}
}
Now if on top of that you want elasticity, it is a bit more tricky: Somewhere, your script must currently set MyScrollRectContent.transform.localPosition. Instead of doing that, set a targetYPosition. You can imagine this as a point that moves, on which the scrollrect is linked by an elastic. This targetYPosition is contrained by your limit. Then in your update you make the ScrollRectContent follow.
public void OnUserInput(float y) // I don't know how you actually do this. this is an example
{
_targetYposition = y;
if(_targetYposition > limit)
{
_targetYPosition = limit;
}
}
private void Update()
{
var currentPos = MyScrollRectContent.transform.localPosition;
var y =
Vector3.Lerp(currentPos.y,
_targetYPosition, Time.deltaTime*_speed);
MyScrollRectContent.transform.localPosition = new Vector3(currentPos.x, y, currentPos.z);
}
Note that this is a simple example aiming at hinting you in the right direction. You'll have to adapt it to your code. The elasticity will likely not look as you want either, so you might want to modify the Update function to create other effects
Related
hey guys , So as you can see i made a robot arm grab a slingshot's objectholder with a ball in it. My arm pulls it any direction I want it but I wanted the user to know which box is going to be shot at.
If you're applying an impulse force (or velocity) to your ball and there is gravity in your world, your item will follow the Projectile motion;
Here you can find details about it:
https://en.wikipedia.org/wiki/Projectile_motion
There are basically two main options
calculating it yourself
This is probably way better for performance especially if you want a really simple trajectory preview without accounting for any collision etc
refer to linked article. But it basically comes down to
and would need slightly rework from 2D to 3D physics, should be trivial though since the important part about the Y axis basically stays the same.
You would
Call this simulation with according supposed shoot direction and velocity
Visualize the tracked positions e.g. in a LineRenderer
Physics.Simulate
This allows you to run physics updates manually all within a single frame and actually let the Physics engine handle it all for you
This costs of course a lot of performance but you get all collisions etc accounted for automatically without getting a headache
You would
Make a snapshot of all Rigid bodies in your scene - in order to reset after the simulation
Simulate the desired amount of physics steps (XY seconds ahead) while keeping track of the simulated data
reset everything to the state tracked in step 1
use the simulated data from step 2 to visualize e.g. with a LineRenderer
This might look somewhat like e.g.
public class Prediction : MonoBehaviour
{
public LineRenderer line;
public Rigidbody tracked;
private Rigidbody[] allRigidbodies;
private void Awake()
{
allRigidbodies = FindObjectsOfType<Rigidbody>();
}
private void LateUpdate()
{
// Wherever you would get this from
Vector3 wouldApplyForce;
// Step 1 - snapshot
// For simplicity reasons for now just the positions
// using some Linq magic
var originalPositions = allRigidbodies.ToDictionary(item => item, item => item.position);
// Step 2 - Simulate e.g. 2 seconds ahead
var trackedPositions = new Vector3 [(int) (2 / Time.fixedDeltaTime)];
Physics.autoSimulation = false;
tracked.AddForce(wouldApplyForce);
for(var i = 0; i < trackedPositions.Length; i++)
{
Physics.Simulate(Time.fixedDeltaTime);
trackedPositions[i] = tracked.position;
}
// Step 3 - reset
foreach (var kvp in originalPositions)
{
kvp.Key.position = kvp.Value;
}
Physics.autoSimulate = true;
// Step 4 - Visualize
line.positionCount = trackedPositions.Length;
line.SetPositions(trackedPositions);
}
}
Of course we won't talk about performance here ^^
I wanted my UI to not resize when user is still resizing the game (holding click in the window border) and only when the user has released the mouse the resize event will trigger.
I have tried to achieve it on Unity but so far I only able to detect windows size change, which my script checked every 0.5 second and if detected change it will resize the UI. But of course resizing everything caused a heavy lag, so resizing every 0.5 second is not a good option but resizing every 1 second is not a good idea either because 1 second is considered too long.
The question might be too broad but I have specified the problem as small as possible, how do I detect if user is still resizing the window? And how do I detect if user has stopped resizing the window (stop holding click at window border)?
You can't tell when someone stops dragging a window, unless you want to code a low level solution for ever desktop environment and every operating system.
Here's what worked for me with any MonoBehavior class, using the OnRectTransformDimensionsChange event:
public class StackOverflow : MonoBehaviour
{
private const float TimeBetweenScreenChangeCalculations = 0.5f;
private float _lastScreenChangeCalculationTime = 0;
private void Awake()
{
_lastScreenChangeCalculationTime = Time.time;
}
private void OnRectTransformDimensionsChange()
{
if (Time.time - _lastScreenChangeCalculationTime < TimeBetweenScreenChangeCalculations)
return;
_lastScreenChangeCalculationTime = Time.time;
Debug.Log($"Window dimensions changed to {Screen.width}x{Screen.height}");
}
}
I have some good news - sort of.
When the user resizes the window on Mac or PC,
Unity will AUTOMATICALLY re-layout everything.
BUT in fact ONLY when the user is "finished" resizing the Mac/PC window.
I believe that is what the OP is asking for - so the good news, what the OP is asking for is quite automatic.
However. A huge problem in Unity is Unity does not smoothly resize elements as the user is dragging the mouse to expand the Mac/PC window.
I have never found a solution to that problem. (A poor solution often mentioned is to check the size of the window every frame; that seems to be about the only approach.)
Again interestingly, what the OP mentions
" ..and if window has stopped resizing .."
is automatically done in Unity; in fact do nothing to achieve that.
I needed something like this for re generating a line chart, but as it has too many elements, it would be heavy to do it on every update, so I came up with this, which for me worked well:
public class ToRunOnResize : MonoBehaviour
{
private float screenWidth;
private bool screenStartedResizing = false;
private int updateCounter = 0;
private int numberOfUpdatesToRunXFunction = 15; // The number of frames you want your function to run after, (usually 60 per second, so 15 would be .25 seconds)
void Start()
{
screenWidth = Screen.width; // Identifies the screen width
}
private void Update()
{
if (Screen.width != screenWidth) // This will be run and repeated while you resize your screen
{
updateCounter = 0; // This will set 0 on every update, so the counter is reset until you release the resizing.
screenStartedResizing = true; // This lets the application know when to start counting the # of updates after you stopped resizing.
screenWidth = Screen.width;
}
if (screenStartedResizing)
{
updateCounter += 1; // This will count the updates until it gets to the numberOfUpdatesToRunXFunction
}
if (updateCounter == numberOfUpdatesToRunXFunction && screenStartedResizing)
{ // Finally we make the counter stop and run the code, in my case I use it for re-rendering a line chart.
screenStartedResizing = false;
// my re-rendering code...
// my re-rendering code...
}
}
}
I'm trying to set up a very simple RTS-like camera that moves around at the pressure of wasd or the arrow keys. But I can't manage to make it work.
I have a player controller that handles input like so:
void AMyPlayerController::SetupInputComponent()
{
Super::SetupInputComponent();
InputComponent->BindAxis("CameraForward", this, &AMyPlayerController::CameraForward);
}
void AMyPlayerController::CameraForward(float Amount)
{
MyRtsCameraReference->CameraForward(Amount);
}
In my camera actor, which inherits from APawn, and I initialize like this:
ARtsCamera::ARtsCamera()
{
PrimaryActorTick.bCanEverTick = true;
CameraComponent = CreateDefaultSubobject<UCameraComponent>(TEXT("CameraComponent"));
SpringArm = CreateDefaultSubobject<USpringArmComponent>(TEXT("SpringArm"));
// I tried to use a static mesh in place of this but nothing changes.
SceneRoot = CreateDefaultSubobject<USceneComponent>(TEXT("SceneRoot"));
MovementComponent = CreateDefaultSubobject<UFloatingPawnMovement>(TEXT("MovementComponent"));
SpringArm->TargetArmLength = 500.f;
SetRootComponent(SceneRoot);
SpringArm->SetupAttachment(SceneRoot);
CameraComponent->SetupAttachment(SpringArm);
SpringArm->AddLocalRotation(FRotator(0.f, -50.f, 0.f));
}
I try to handle the movement like this:
void ARtsCamera::CameraForward(float Amount)
{
if (Amount != 0)
{
// Here speed is a float used to control the actual speed of this movement.
// If Amount is printed here, I get the correct value of 1/-1 at the pressure of w/s.
MovementComponent->AddInputVector(GetActorForwardVector() * Amount * Speed);
}
}
In my set up i then create a blueprint which inherits from this to expose to the level design phase a few parameters like Speed or the spring arm length and so on, but this shouldn't be the issue as if I use the C++ class the behaviour is the same.
The following works as expected (except for the fact that when i then rotate the camera, vectors get messed up) but i would like to use a movement component.
void ARtsCamera::CameraForward(float Amount)
{
if (Amount != 0)
{
AddActorWorldOffset(GetActorForwardVector() * Amount * CameraMovingSpeed);
}
}
The mobility is set to movable. And so far everything seems to be simple enough, no compile errors, but the actor doesn't move. What am I missing?
Also would you use the FloatingPawnMovement for this or would you go for another movement component?
Thanks in advance.
I hate to ask such a generic question but I'm really stuck and super hoping someone can help me along the way. Here is the situation:
I'm making the GUI for a mobile app, portrait mode. I'm using canvas scalers to scale my canvasses with a reference width of 1080. This means I effectively don't know the height of my screen space.
What I want to create is a menu with a variable amount of items. The menu must be anchored to the bottom (with an offset margin) and grow upwards. So far I've been able to manage this using VerticalLayoutGroup and anchoring the rect transform to the bottom.
But my last requirement is that if the content would grow too big, a scrollbar would appear. The definition of the content being too big is: if it would extend the (unknown) screen height ( minus the offset margin of course). I hope the following image illustrates this much clearer:
I have a unity project here: https://ufile.io/v31br
Did you give a try to scrollView? here it is: https://unity3d.com/learn/tutorials/topics/user-interface-ui/scroll-view
You can use your vertical layout inside it and you will probably want to deactivate horizontal scroll and delete the horizontal slider.
Via script you can check its rectTransform height and compare it to your container's size, when reached maxHeight you can start managing your item's sizes
I assume you use the ScrollRect component as it is the right component to use in your case.
You can check the screen height with the Screen.height property.
Once you know the screen height you can compare it with your rect height and toggle the scrollbar with the ScrollRect.vertical property. You may have to change the ScrollRect.verticalScrollbarVisibility to permanent in order to make it work for you.
The answer Dave posted was close, but the problem is that the scrollview doesn't expand. I fixed it eventually by stretching the scrollview and resizing the parent manually as items are added. I set the anchors to the maximum size and adjust the sizeDelta.
public class MenuScript : MonoBehaviour
{
public int MenuItemCount;
public GameObject MenuItemPrefab;
public Transform MenuItemParent;
private RectTransform _rectTransform;
void Start()
{
_rectTransform = GetComponent<RectTransform>();
for (var i = 0; i <= MenuItemCount; i++)
{
GameObject instance = Instantiate(MenuItemPrefab, MenuItemParent, false);
instance.GetComponent<Text>().text = instance.name = "Item " + i;
float size = instance.transform.GetComponent<RectTransform>().sizeDelta.y;
TryExpandBy(size + 10);
}
}
private void TryExpandBy(float size)
{
var deltaY = _rectTransform.sizeDelta.y + size;
if (deltaY > 0) deltaY = 0;
_rectTransform.sizeDelta = new Vector2(_rectTransform.sizeDelta.x, deltaY);
}
}
I make a game in Unity3D (+2D ToolKit) for iOS.
It is 2d runner/platformer with side view. So on screen is moving background and obstacles. And we control up/down the main character to overcome obstacles.
The problem is that the moving picture has a visual lag. In other words, it moves jerkily or creates the tail area of the previous frames on iOS-devices. In XCode the number of frames is 30 and over.
I have objects 'plain' with the following script:
public class Move: Monobehavior
{
private float x;
public float Speed = 128.0f;
void Start()
{
x = transform.position.x;
}
void Update()
{
x += Time.DeltaTime *Speed;
Vector3 N = transform.position;
N.x = mathf.FloorInt(x);
transform.position = N;
}
}
The question is how to make the move of background smoother, without jerks and flicker on screen while playing? Maybe the problem is in framerate parameter.
Can anybody help me to find a solution?
I'd say it's the use of the FloorInt function which will move the background only in steps of 1 which is rather not smooth. It should get better when you comment that line out. Do you have any special reason why you are doing the FloorInt there?
The use of floor will definitely hurt your performance. Not only is it one more thing to calculate, but it is actually removing fidelity by removing decimals. This will definalty make the movement look 'jerky'. Also, update is not always called on the same time inteval, depending on what else is happening during that frame, so using Time.delaTime is highly recommended. Another thing, you do not need to set variables for x and Vector3 N, when you can update the transoms position like the code below. And if you have to, you sill only need to create one variable to update, and set your position to it. The code below just updates the players x position at a given rate, based on the amount of time that has passes since the last update. There should be no 'jerky' movement. (Unless you have a serious framerate drop);
public class Move: Monobehavior
{
public float Speed = 128.0f;
void Update()
{
transform.position =
(transform.position.x + (speed*Time.DeltaTime),
transform.position.y,
transform.position.z);
}
}