How to add Actor and move it in Unreal Editor? - unreal-engine4

I'm new in game development. Pass a training course Get Started (https://docs.unrealengine.com/latest/INT/Programming/QuickStart/7/index.html) I created a class AMyActorTest extended AActor:
#include "TestUProject.h"
#include "MyActorTest.h"
AMyActorTest::AMyActorTest(const class FPostConstructInitializeProperties& PCIP)
: Super(PCIP)
{
MyNumber = 12;
}
void AMyActorTest::BeginPlay()
{
Super::BeginPlay();
if (GEngine)
{
GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Yellow, TEXT("Hello World!"));
GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Yellow, FString::FromInt(MyNumber));
}
}
I have a problem that I can not move in Editor to AActor after placing it in ViewPort. I read that I was missing RootComponent for my Actor, but I do not understand how to add it (maybe I do not fully understand actors). Can help you have my source code to solve my problem? This code is doing in terms of training.
My goal - to add an actor and be able to move and rotate it.

Please add this code
RootComponent = PCIP.CreateDefaultSubobject<USceneComponent>(this, TEXT("Root"));
to your constructor. That's all. If you'd like to add another components, you can use similar code (this example creates UInstancedStaticMeshComponent :
UInstancedStaticMeshComponent* instancedComp = PCIP.CreateDefaultSubobject<UInstancedStaticMeshComponent>(RootComponent, TEXT("SubMeshInstanced"));
instancedComp->AttachTo(RootComponent); // this is important!
// this part is specific to this component
// (although all are common to other types of your Root subitems)
instancedComp->SetStaticMesh(mesh);
instancedComp->SetMaterial(0, material);
instancedComp->bOwnerNoSee = false;
instancedComp->bCastDynamicShadow = false;
instancedComp->CastShadow = false;
instancedComp->SetHiddenInGame(false);
instancedComp->SetMobility(EComponentMobility::Static);

Related

Unity3D New Input System: Is it really so hard to stop UI clickthroughs (or figure out if cursor is over a UI object)?

Even the official documentation has borderline insane recommendations to solve what is probably one of the most common UI/3D interaction issues:
If I click while the cursor is over a UI button, both the button (via the graphics raycaster) and the 3D world (via the physics raycaster) will receive the event.
The official manual:
https://docs.unity3d.com/Packages/com.unity.inputsystem#1.2/manual/UISupport.html#handling-ambiguities-for-pointer-type-input essentially says "how about you design your game so you don't need 3D and UI at the same time?".
I cannot believe this is not a solved problem. But everything I've tried failed. EventSystem.current.currentSelectedGameObject is sticky, not hover. PointerData is protected and thus not accessible (and one guy offered a workaround via deriving your own class from Standalone Input Module to get around that, but that workaround apparently doesn't work anymore). The old IsPointerOverGameObject throws a warning if you query it in the callback and is always true if you query it in Update().
That's all just mental. Please someone tell me there's a simple, obvious solution to this common, trivial problem that I'm just missing. The graphics raycaster certainly stores somewhere if it's over a UI element, right? Please?
I've looked into this a fair bit and in the end, the easiest solution seems to be to do what the manual says and put it in the Update function.
bool pointerOverUI = false;
void Update()
{
pointerOverUI = EventSystem.current.IsPointerOverGameObject();
}
Your frustration is well founded: there are NO examples of making UI work with NewInput which I've found. I can share a more robust version of the Raycaster workaround, from Youtube:
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.InputSystem;
using UnityEngine.UI;
/* Danndx 2021 (youtube.com/danndx)
From video: youtu.be/7h1cnGggY2M
thanks - delete me! :) */
public class SCR_UiInteraction : MonoBehaviour
{
public GameObject ui_canvas;
GraphicRaycaster ui_raycaster;
PointerEventData click_data;
List<RaycastResult> click_results;
void Start()
{
ui_raycaster = ui_canvas.GetComponent<GraphicRaycaster>();
click_data = new PointerEventData(EventSystem.current);
click_results = new List<RaycastResult>();
}
void Update()
{
// use isPressed if you wish to ray cast every frame:
//if(Mouse.current.leftButton.isPressed)
// use wasReleasedThisFrame if you wish to ray cast just once per click:
if(Mouse.current.leftButton.wasReleasedThisFrame)
{
GetUiElementsClicked();
}
}
void GetUiElementsClicked()
{
/** Get all the UI elements clicked, using the current mouse position and raycasting. **/
click_data.position = Mouse.current.position.ReadValue();
click_results.Clear();
ui_raycaster.Raycast(click_data, click_results);
foreach(RaycastResult result in click_results)
{
GameObject ui_element = result.gameObject;
Debug.Log(ui_element.name);
}
}
}
So, just drop into my "Menusscript.cs"?
But as a pattern, this is terrible for separating UI concerns. I'm currently rewiring EVERY separately-concerned PointerEventData click I had already working, and my question is, Why? I can't even find how it's supposed to work: to your point there IS no official guide at all around clicking UI, and it does NOT just drop-on-top.
Anyway, I haven't found anything yet which makes new input work easily on UI, and definitely not found how I'm going to sensibly separate Menuclicks from Activityclicks while keeping game & ui assemblies separate.
Good luck to us all.
Unity documentation for this issue with regard to Unity.InputSystem can be found at https://docs.unity3d.com/Packages/com.unity.inputsystem#1.3/manual/UISupport.html#handling-ambiguities-for-pointer-type-input.
IsPointerOverGameObject() can always return true if the extent of your canvas covers the camera's entire field of view.
For clarity, here is the solution which I found worked best (accumulated from several other posts across the web).
Attach this script to your UI Canvas object:
public class CanvasHitDetector : MonoBehaviour {
private GraphicRaycaster _graphicRaycaster;
private void Start()
{
// This instance is needed to compare between UI interactions and
// game interactions with the mouse.
_graphicRaycaster = GetComponent<GraphicRaycaster>();
}
public bool IsPointerOverUI()
{
// Obtain the current mouse position.
var mousePosition = Mouse.current.position.ReadValue();
// Create a pointer event data structure with the current mouse position.
var pointerEventData = new PointerEventData(EventSystem.current);
pointerEventData.position = mousePosition;
// Use the GraphicRaycaster instance to determine how many UI items
// the pointer event hits. If this value is greater-than zero, skip
// further processing.
var results = new List<RaycastResult>();
_graphicRaycaster.Raycast(pointerEventData, results);
return results.Count > 0;
}
}
In class containing the method which is handling the mouse clicks, obtain the reference to the Canvas UI either using GameObject.Find() or a public exposed variable, and call IsPointerOverUI() to filter clicks when over UI.
Reply to #Milad Qasemi's answer
From the docs you have attached in your answer, I have tried the following to check if the user clicked on a UI element or not.
// gets called in the Update method
if(Input.GetMouseButton(0) {
int layerMask = 1 << 5;
// raycast in the UI layer
RaycastHit2D hit = Physics2D.Raycast(Camera.main.ScreenToWorldPoint(Input.mousePosition), Vector2.zero, Mathf.Infinity, layerMask);
// if the ray hit any UI element, return
// don't handle player movement
if (hit.collider) { return; }
Debug.Log("Touched not on UI");
playerController.HandlePlayerMovement(x);
}
The raycast doesn't seem to detect collisions on UI elements. Below is a picture of the Graphics Raycaster component of the Canvas:
Reply to #Lowelltech
Your solution worked for me except that instead of Mouse I used Touchscreen
// Obtain the current touch position.
var pointerPosition = Touchscreen.current.position.ReadValue();
An InputSytem is a way to receive new inputs provided by Unity. You can't use existing scripts there, and you'll run into problems like the original questioner. Answers with code like "if(Input.GetMouseButton(0)" are invalid because they use the old system.

Unity2d: Trying to change the color of a GameObject from a different class

So I can see that the GameObject is in the List but it gives me a "Object reference not set to an instance of the object" error when trying to change color to it.
public class Paint : MonoBehaviour
{
//inside Create is where the list of objects are created
Create create = new Create();
ColorPicker colorPicker = new ColorPicker();
public void SetColor()
{
create = GetComponent<Create>();
if (create.GraffitiLetters.Count > 0)
{
colorPicker = GetComponent<ColorPicker>();
for (int i = 0; i < create.GraffitiLetters.Count; i++)
{
create.GraffitiLetters[i].GetComponent<Image>().color = colorPicker.GetColor();
}
}
}
}
I bet it has something to do with me having to get hold of the component first but I dunno?
----------------------EDIT--------------------------
OK, new attempt for the same problem.
I have a class called ColorPicker. Inside of it I have a Color color; which gets an rgba value.
Now I want to grab that value from another class. How?
Inside my Paint class I tried this.
ColorPicker colorPicker = new ColorPicker();
colorPicker = GameObject.Find("color").GetComponent<ColorPicker>();
Debug.Log(colorPicker.color);
I've also tried various other ways but I just don't get it. seems like a simple problem.
--------- Second edit------------------
I have tried all of these. I can't understand it. all the questions that seem similar has gotten one of these answers. nothing works for me.
//This Gets NullReferenceException
//Debug.Log("test color" + colorPicker.GetComponent<ColorPicker> ().GetColor());
//This Gets NullReferenceException
//colorPicker.GetComponent<Color>();
//Debug.Log("test 2" + colorPicker.color);
//This Gets NullReferenceException
// colorPicker.transform.Find("color");
// colorPicker.GetComponent<Color>();
// Debug.Log("test 3 " + colorPicker.color);
You did not specify what line gives the Null Reference Exception, so proper help cannot be given. I will write down some things that may be the issue:
Create create = new Create();
This is not the issue, but it's confusing. I don't think you want to instansiate this class, it makes no sense. What value is an empty instance. You're later setting it to this GameObject's component, which makes sense through create = GetComponent<Create>();.
So I'll assume that create is null. This means you haven't attached the Create component/script to the GameObject that has the Paint script on it.
If that is not the case, I'm guessing your issue lies in the next step, namely that the create.GraffitiLetters[i] may not have an Image component.
Sidenote: Since your Paint class is dependant on its GameObject having a Create script, you could set an attribute on the class, that validates it for you:
[RequireComponent(typeof(Create))]
public class Paint: MonoBehaviour

Can't load another level

I was following an online tutorial to make this little game in Unity and when I got to the end, I wound up with two different levels. The only problem is that I can only play one of them. I tried adding it in the build settings but for some reason, it just isn't working. Maybe there's a problem with the code? I don't know. This is my first-ever working with Unity so I'm still figuring things out.
public class LevelControllerScript : MonoBehaviour
{
private static int _nextLevelIndex = 1;
private NewBehaviourScript1[] _enemies;
private void OnEnable()
{
_enemies = FindObjectsOfType<NewBehaviourScript1>();
}
// Update is called once per frame
void Update()
{
foreach(NewBehaviourScript1 NewBehaviourScript1 in _enemies)
{
if (NewBehaviourScript1 != null)
return;
}
Debug.Log("You killed all enemies!");
_nextLevelIndex++;
string nextLevelName = "Level" + _nextLevelIndex;
SceneManager.LoadScene(nextLevelName);
}
}
string nextLevelName = "Level" + _nextLevelIndex;
This line of code makes the string nextLevelName something like Level1, or Level2, however, you are trying to match up to the string leveltwo.
To fix this you need to match up the strings, I believe you can just change the scene leveltwo to Level2 (and change all of the other scenes accordingly).

UNITY An object reference is required to access non-static member `Outline.OutlineMode'

I'm trying to create an outline when you are near it, but i'm getting all the time the same error.
void Update () {
if (Input.GetKeyDown(KeyCode.E)){
var outline = gameObject.AddComponent<Outline>();
outline.OutlineMode = Outline.Mode.OutlineAll;
outline.OutlineColor = Color.yellow;
outline.OutlineWidth = 5f;
}
}
void OnTriggerStay(Collider other) {
if (Outline.OutlineMode == Outline.Mode.OutlineAll) {
Debug.Log("test");
}
}
If i press E it works, and if i change it to ontriggerstay works too, but im trying that it only applies one time, because im getting some errors if its on. I have to say that im using an asset, called quick outline
Srry for my very bad english and explanation and thank you
add the outline to your object in Awake() then set it to disabled.
then enable it in OnTriggerEnter() and disable it in OnTriggerExit()
this will keep you from making multiple copies, and it will only be active when you are in range of your trigger

Telling another GameObject to do something (Unity2D)?

I have a simple touch/mouseclick script attached to a GameObject as a sort of "Master Script" i.e. the GameObject is invisible and doesn't do anything but hold this Touch script when the game is running.
How do I tell other named GameObjects that are generated at runtime to do things e.g. highlight when touched/clicked from this Master Script?
The script for highlighting seems to be: renderer.material.color= colorRed;
But I'm not sure how to tell the GameObject clicked on to become highlighted from the Master Script.
Please help! (am programming in C#)
Thanks!
Alright so you'll want to use a ray cast if you're not doing it in GUI. Check out Unity Ray Casting and then use
hit.transform.gameObject.renderer.material.color = red;
You can have a switch that is like:
if (hit.transform.gameObject.CompareTag("tag")) {
// turn to red;
} else {
// turn to white;
}
Use the ScreenPointToRay or ScreenPointToWorld depending on what you're doing.
For touch, should look like:
void Update () {
foreach (Touch touch in Input.touches)
{
Ray ray = Camera.main.ScreenPointToRay(touch.position);
RaycastHit hit;
if (Physics.Raycast(ray, out hit, 1000.0f))
{
if (hit.collider.gameObject.CompareTag("tag"))
{
hit.collider.gameObject.renderer.material.color = red;
}
}
}
// You can also add in a "go back" feature in the update but this will "go back" then when the touch ends or moves off
// Also not so good to search for Objects in the update function but that's at your discretion.
GameObject[] gObjs = GameObject.FindGameObjectsWithTag("tag");
foreach (GameObject go in gObjs) {
go.renderer.material.color = white;
}
}
To answer your question about pinging the 'manager'
I would do one of two options.
Either:
// Drop the object containing YourManager into the box in the inspector where it says "manage"
public YourManager manage;
// In the update and in the Ray Cast function (right next to your color change line):
manager.yourCall ();
// and
manager.yourString = "cool";
OR
private YourManager manage;
void Awake () {
manager = GameObject.FindObjectWithTag("manager").GetComponent<YourManager> ();
}
// In the update and in the Ray Cast function (right next to your color change line):
// In your manager file have "public bool selected;" at the top so you can access that bool from this file like:
manager.selected = true;
I detail this a little in another one of my answers HERE
For mouse clicks, I would check out the MonoDevelop functions they have in store such as:
// This file would be on the game object in the scene
// When the mouse is hovering the GameObject
void OnMouseEnter () {
selected = true;
renderer.material.color = red;
}
// When the mouse moved out
void OnMouseExit () {
selected = false;
renderer.material.color = white;
}
// Or you can use the same system as above with the:
Input.GetMouseButtonDown(0))
Resolution:
Use a bool in your manager file true is selected, false isn't. Have all the objects you instantiate have a tag, use the ray cast from the master file to the game object. When it his the game object with that tag, swap colors and sap the bool from the master file. Probably better to do it internally from the master file.
(All depends on what you're doing)
If you know what the name of the GameObjects will be at runtime, you can use GameObject.Find("") and store that in a GameObject variable. You can then set the renderer of that GameObject to whatever you like (assuming a renderer is linked to that GameObject).
The most obvious way of doing this would be to use prefabs and layers or tags.
You can add a tag to your prefab (say "Selectable") or move the prefab to some "Selectable" layer and then write your code around this, knowing that all selectable items are on this layer/have this tag.
Another way of doing this (And in my opinion is also a better way) is implementing your custom 'Selectable' component. You would search for this component on a clicked item and then perform the selection, if you have found that component. This way is better because you can add some additional selection logic in this component which would otherwise reside in your selection master script (image the size of your script after you've added a couple of selectables).
You can do it by implementing a SelectableItem script (name is arbitrary) and a couple of it's derivatives:
public class SelectableItem : MonoBehavior {
public virtual void OnSelected() {
renderer.material.color = red;
}
}
public class SpecificSelectable : SelectableItem {
public override void OnSelected() {
//You can do whatever you want in here
renderer.material.color = green;
}
}
//Adding new selectables is easy and doesn't require adding more code to your master script.
public class AnotherSpecificSelectable : SelectableItem {
public override void OnSelected() {
renderer.material.color = yellow;
}
}
And in your master script:
// Somewhere in your master selection script
// These values are arbitrary and this whole mask thing is optional, but would improve your performance when you click around a lot.
var selectablesLayer = 8;
var selectablesMask = 1 << selectablesLayer;
//Use layers and layer masks to only raycast agains selectable objects.
//And avoid unnecessary GetComponent() calls.
if (Physics.Raycast(ray, out hit, 1000.0f, selectablesMask))
{
var selectable = hit.collider.gameObject.GetComponent<SelectableItem>();
if (selectable) {
// This one would turn item red or green or yellow depending on which type of SelectableItem this is (which is controlled by which component this GameObject has)
// This is called polymorphic dispatch and is one of the reasons we love Object Oriented design so much.
selectable.OnSelected();
}
}
So say you have a couple of different selectables and you want them to do different things upon selection. This is the way you would do this. Some of your selectables would have one of the selection components and others would have another one. The logic that performs the selection resides in the Master script while the actions that have to be performed are in those specific scripts that are attached to game objects.
You can go further and add OnUnselect() action in those Selectables:
public class SelectableItem : MonoBehaviour {
public virtual void OnSelected() {
renderer.material.color = red;
}
public virtual void OnUnselected() {
renderer.material.color = white;
}
}
and then even do something like this:
//In your master script:
private SelectableItem currentSelection;
var selectable = hit.collider.gameObject.GetComponent<SelectableItem>();
if (selectable) {
if (currentSelection) currentSelection.OnUnselected();
selectable.OnSelected();
CurrentSelection = selectable;
}
And we've just added deselection logic.
DISCLAIMER: These are just a bunch of snippets. If you just copy and paste those they probably wouldn't work right away.