koobas.hobune.stream
Getting a sprites size in pixels
Hi guys, I'm trying to get the width / height of a sprite in pixels by doing this
_cam.WorldToScreenPoint( GetComponent().bounds.size );
this gives me a daft value of around 400 pixels high when I can see that it is no where near that size.
Am I doing something wrong here, I've tried a few other variations as well?
Cheers
Hey
GetComponent() is a bit weird - that shouldn't compile. Are you getting the bounds of a box collider 2d or something?
Yeah sorry meant type Renderer in angle brackets - its removes them on here
It's a bit of a tricky problem, as it depends on your camera too. The world to screen point is definitely not what you want, as that'll treat the size as though it were a world position, which it isn't.
Are you using an orthographic or perspective camera?
orthographic - doesn't bounds.size / bounds.extent return a value in world co-ords?
Have you tried using sprite.rect.height and sprite.rect.width? Alternatively, maybe sprite.bounds.height/width with sprite.pixelsPerUnit
Orthograph cameras aren't too tricky as they don't scale with depth. You'll need to:
Take the sprite bounds which are in world space (I was incorrect in my comment above)
Use the camera orthographic size to get the size in screen space (-2 to 2 in x and y)
Then scale that by the camera pixel width/height to get size in pixels
EDIT: I've added the 2nd approach that handles rotation.
Something like this:
//get world space size (this version operates on the bounds of the object, so expands when rotating)
//Vector3 world_size = GetComponent<SpriteRenderer>().bounds.size;
//get world space size (this version handles rotating correctly)
Vector2 sprite_size = GetComponent<SpriteRenderer>().sprite.rect.size;
Vector2 local_sprite_size = sprite_size / GetComponent<SpriteRenderer>().sprite.pixelsPerUnit;
Vector3 world_size = local_sprite_size;
world_size.x *= transform.lossyScale.x;
world_size.y *= transform.lossyScale.y;
//convert to screen space size
Vector3 screen_size = 0.5f * world_size / Camera.main.orthographicSize;
screen_size.y *= Camera.main.aspect;
//size in pixels
Vector3 in_pixels = new Vector3(screen_size.x * Camera.main.pixelWidth, screen_size.y * Camera.main.pixelHeight, 0) * 0.5f;
Debug.Log(string.Format("World size: {0}, Screen size: {1}, Pixel size: {2}",world_size,screen_size,in_pixels));
No rotation, I gave it a try and it gave me something like (25, 45) for in_pixels. Given that my sprite is square that can't be right can it?
Bit more info - Screen size is 480 wide by 800 high Sprite is currently about 48 by 48 at a guess
Ok - I'm really not having a good day - give me 5 $$anonymous$$utes :)
You can use the Sprite.Rect parameter, that stores height and width in pixel
That only gives the set sprite asset pixel size, which generally defeats the purpose of measuring the size during runtime.
i.e. if you scale the sprite in any way it'll still read you the defined asset pixel size, not the current size after scaling.
I suggest something like:
var originalSpriteSize = image.sprite.rect;
image.sprite = protoSprite.ToSprite();
image.color = protoSprite.ToGameSpriteImage().Color;
var newSpriteSize = image.sprite.rect;
var scaleFactorWidth = originalSpriteSize.width / newSpriteSize.width;
var scaleFactorHeight = originalSpriteSize.height / newSpriteSize.height;
image.transform.localScale = new Vector3(scaleFactorWidth * image.transform.localScale.x, scaleFactorHeight * image.transform.localScale.y, image.transform.localScale.z);
