edx/assignment9final/Assets/Standard Assets/Utility/AlphaButtonClickMask.cs
2022-11-10 21:56:29 -03:00

59 lines
1.7 KiB
C#
Executable File

using UnityEngine;
using UnityEngine.UI;
using System.Collections;
public class AlphaButtonClickMask : MonoBehaviour, ICanvasRaycastFilter
{
protected Image _image;
public void Start()
{
_image = GetComponent<Image>();
Texture2D tex = _image.sprite.texture as Texture2D;
bool isInvalid = false;
if (tex != null)
{
try
{
tex.GetPixels32();
}
catch (UnityException e)
{
Debug.LogError(e.Message);
isInvalid = true;
}
}
else
{
isInvalid = true;
}
if (isInvalid)
{
Debug.LogError("This script need an Image with a readbale Texture2D to work.");
}
}
public bool IsRaycastLocationValid(Vector2 sp, Camera eventCamera)
{
Vector2 localPoint;
RectTransformUtility.ScreenPointToLocalPointInRectangle(_image.rectTransform, sp, eventCamera, out localPoint);
Vector2 pivot = _image.rectTransform.pivot;
Vector2 normalizedLocal = new Vector2(pivot.x + localPoint.x / _image.rectTransform.rect.width, pivot.y + localPoint.y / _image.rectTransform.rect.height);
Vector2 uv = new Vector2(
_image.sprite.rect.x + normalizedLocal.x * _image.sprite.rect.width,
_image.sprite.rect.y + normalizedLocal.y * _image.sprite.rect.height );
uv.x /= _image.sprite.texture.width;
uv.y /= _image.sprite.texture.height;
//uv are inversed, as 0,0 or the rect transform seem to be upper right, then going negativ toward lower left...
Color c = _image.sprite.texture.GetPixelBilinear(uv.x, uv.y);
return c.a> 0.1f;
}
}