I am making a game in Unity and I have a Canvas set to Screen Space - Overlay and it has that background green as you can see from the image. I also have a RawImage with the background blue as a child of the Canvas and the player will have to draw an object like a car or a house inside the RawImage.Right now, the line Instantiates in a random position on the screen even if I give it the coordinated (0, 0).
What I need help with is to find a way to convert the coordinates so I only work with the inside coordinates of the RawImage. For example, the (0, 0) coordinate I will pass to the line, has to be converted to the bottom-left corner of the RawImage. and the maximum width or height should also depend on the RawImage width and height.
Here is the CreateLine function I have for now:
public void CreateLine(int x, int y)
{
currentLine = Instantiate(linePrefab, Vector3.zero, Quaternion.identity);
currentLine.transform.parent = GameObject.Find("GameMenu(Clone)").transform; //Make the line a child of the Canvas named GameMenu
lineRenderer = currentLine.GetComponent<LineRenderer>();
lineRenderer.SetPosition(0, new Vector3(x, y, 99));
lineRenderer.SetPosition(1, new Vector3(x, y, 99));
}
Any amount of help will be greatly appreciated. Have a great day!
Related
I'm struggling with this sort of
Screen disposition.
I want to position my Camera so that the world is positionned like in the image with the origin at bottom left. It's easy to set the orthographicSize of the camera as I know how many unit I want vertically. It is also easy to calculate the Y position of the camera as I just want it to be centered vertically. But I cannot find how to compute the X position of the camera to put the origin of the world in this position, no matter what the aspectRatio of the screen is.
It brings me two questions :
How can I calculate the X position of the camera so that the origin of the world is always as the same distance from the screen left and bottom borders ?
Instead of positioning the camera regarding the UI, should I use RenderMode Worldspace for the UI canvas. And if so, how could I manage responsiveness ?
I don't understand the second question, but regarding positioning the Camera on the X axis so that the lower left corner is always at world 0 you could do the following:
var lowerLeftScreen = new Vector3(0, 0, 10);
var pos = transform.position;
var lowerLeftScreenPoint = Camera.main.ScreenToWorldPoint(lowerLeftScreen).x;
if (lowerLeftScreenPoint > 0)
{
pos.x -= lowerLeftScreenPoint;
}
else
{
pos.x += Mathf.Abs(lowerLeftScreenPoint);
}
transform.position = pos;
Debug.Log(Camera.main.ScreenToWorldPoint(lowerLeftScreen));
Not the nicest code, but gets the job done.
Also the Z component in the Vector does not really matter for our orthographic camera.
In Unity, is there a way to detect in the camera's field of view, if a cube object is infront of a text component which is in World Space? Such that the cube blocks the text in camera's FoV?
//this is your object that you want to have the UI element hovering over
GameObject WorldObject;
//this is the ui element
RectTransform UI_Element
//first you need the RectTransform component of your canvas
RectTransform CanvasRect=Canvas.GetComponent<RectTransform>();
//then you calculate the position of the UI element
//0,0 for the canvas is at the center of the screen, whereas WorldToViewPortPoint
//treats the lower left corner as 0,0. Because of this, you need
//to subtract the height / width of the canvas * 0.5 to get the correct position.
Vector2 viewportPosition=Cam.WorldToViewportPoint(WorldObject.transform.position);
Vector2 WorldObject_ScreenPosition=new Vector2(
((ViewportPosition.x*CanvasRect.sizeDelta.x)-(CanvasRect.sizeDelta.x*0.5f)),
((ViewportPosition.y*CanvasRect.sizeDelta.y)-(CanvasRect.sizeDelta.y*0.5f)));
//now you can set the position of the ui element
UI_Element.anchoredPosition=WorldObject_ScreenPosition;
It helped me in the past and i hope it will help you too
font: https://answers.unity.com/questions/799616/unity-46-beta-19-how-to-convert-from-world-space-t.html
I am trying to place my camera on the x-axis relative to a gameobject (in my case a sphere). I need this to preview only the half of that sphere no matter what resolution the window will be.
So if the user resizes the window, the camera should adjust itself to only see the left half. See the attached Image. Red is the cameras view and black is the Sphere
Using the Camera.ViewerportPointToRay function you can get a position and direction in world space from a point on the screen. Screen coordinates are defined as (0,0) on the bottom left to (1, 1) on the top right. So to position the sphere on the middle right of the screen you'll want to convert the screen coordinate (1, 0.5) to world coordinates.
Here's an idea of how to get the point on the middle-right of the screen half-way between the near and far clip planes of the camera:
// get the world ray from screen coordinates
Ray ray = camera.ViewpoirtPointToRay(new Vector3(1, 0.5, 0));
// make the z-component of the direction 1
ray.direction /= ray.direction.z;
// get the world position for where to place the sphere by scaling the ray
// halfway down the camera's frustum
Vector3 worldPos = ray.origin + ray.direction * (camera.far - camera.near) * 0.5;
sphere.position = worldPos;
Hopefully that helps! Let me know if anything is unclear!
I have this code that instantiates GameObjects at the top of the screen and then they fall down.
float RandX = GetRandomXPos();
float RandY = screenSize.y;
Vector3 ballPos = new Vector3(RandX,RandY,0);
GameObject clone = Instantiate(BallPrefab, ballPos, transform.rotation) as GameObject;
This works fine but it spawn them at the top of the screen so they just blink into existence. I want to spawn them at the top of the screen plus the height of the prefab so that it can appear out of view and then fall down into view.
What is the best way to get that height that I need to offset by?
To get the size of the prefab you need to get the information of the Renderer that the prefab has.
To do this you have to get the component in its hierarchy, you can do this by using GetComponentInChildren<Renderer>()
Once you got the Renderer, you can access the bounds size with renderer.bounds.size
This is a Vector3 which has the dimensions of the object, height being the Y component.
You may have more than one Renderer in a prefab so you will need to get them all with GetComponentsInChildren<Renderer>(). and calculate the sum of all the bounds using bounds.Encapsulate
var renderer = target.GetComponentInChildren<Renderer>();
var height = renderer.bounds.size.y;
In my Unity2D project, I am trying to spawn my sprite on top of each other and across the entire height of the device's screen. For example to give an idea, think of a box on top of each other across the entire device's screen height. In my case, I'm spawning arrow sprites instead of boxes
I already got the sprites spawning on top of each other successfully. My problem now is how to calculate how many sprites to spawn to make sure it spreads across the screen's height.
I currently have this snippet of code:
public void SpawnInitialArrows()
{
// get the size of our sprite first
Vector3 arrowSizeInWorld = dummyArrow.GetComponent<Renderer>().bounds.size;
// get screen.height in world coords
float screenHeightInWorld = Camera.main.ScreenToWorldPoint(new Vector3(0, Screen.height, 0)).y;
// get the bottom edge of the screen in world coords
Vector3 bottomEdgeInWorld = Camera.main.ScreenToWorldPoint(new Vector3(0,0,0));
// calculate how many arrows to spawn based on screen.height/arrow.size.y
int numberOfArrowsToSpawn = (int)screenHeightInWorld / (int)arrowSizeInWorld.y;
// create a vector3 to store the position of the previous arrow
Vector3 lastArrowPos = Vector3.zero;
for(int i = 0; i < numberOfArrowsToSpawn; ++i)
{
GameObject newArrow = this.SpawnArrow();
// if this is the first arrow in the list, spawn at the bottom of the screen
if(LevelManager.current.arrowList.Count == 0)
{
// we only handle the y position because we're stacking them on top of each other!
newArrow.transform.position = new Vector3(newArrow.transform.position.x,
bottomEdgeInWorld.y + arrowSizeInWorld.y/2,
newArrow.transform.position.z);
}
else
{
// else, spawn on top of the previous arrow
newArrow.transform.position = new Vector3(newArrow.transform.position.x,
lastArrowPos.y + arrowSizeInWorld.y,
newArrow.transform.position.z);
}
// save the position of this arrow so that we know where to spawn the next arrow!
lastArrowPos = new Vector3(newArrow.transform.position.x,
newArrow.transform.position.y,
newArrow.transform.position.z);
LevelManager.current.arrowList.Add(newArrow);
}
}
The problem with my current code is that it doesn't spawn the correct number of sprites to cover the entire height of the device's screen. It only spawns my arrow sprites approximately up to the middle of the screen. What I want is for it to be able to spawn up to the top edge of the screen.
Anyone know where the calculation went wrong? and how to make the current code cleaner?
If sprites are rendered via camera mode in perspective and the sprites appear to have varying sizes when displayed on the screen (sprites farther away from the camera are smaller than sprites that are closer to the camera) then a new way to calculate the numberOfArrowsToSpawn value is needed.
You could try adding sprites with a while loop, instead of using a for loop, just continue creating sprites until the calculated world position for the sprite will no longer be visible to the camera. Check to see if a point will be visible in camera by using the technique Jessy provides in this link:
http://forum.unity3d.com/threads/point-in-camera-view.72523/
I think your screenHeightInWorld is really a screenTopInWorld, a point can be anywhere in the space.
You need the relative screen height in world coordinate.
Which is actially the half of the camera frustum size if you use ortographic projection, as you think of it.
float screenHeightInWorld = Camera.main.orthographicSize / 2.0f;
I did not read the rest, but is probably fine, up to you how you implement this.
I'd simply create an arrow method, something like bool SpawnArrowAboveIfFits(), which can call itself iteratively on the new instances.