ugui 基于图片透明度的点击过滤器

using UnityEngine;

using System.Collections;

using UnityEngine.UI;

using System.IO;

 

[DisallowMultipleComponent]

[RequireComponent(typeof(Image))]

[ExecuteInEditMode]

public class ImageRaycastFilter : MonoBehaviour, ICanvasRaycastFilter

{

    public bool reversed;

 

    private Image image;

 

    void OnEnable()

    {

        image = GetComponent<Image>();

        image.type = Image.Type.Simple;

    }

 

    public bool IsRaycastLocationValid(Vector2 screenPoint, Camera eventCamera)

    {

        if (!enabled)

            return true;

 

        Sprite sprite = image.overrideSprite;

        if (sprite == null)

            return true;

 

        Vector2 local;

        RectTransformUtility.ScreenPointToLocalPointInRectangle(image.rectTransform, screenPoint, eventCamera, out local);

 

        Rect rect = image.rectTransform.rect;

 

        // Convert to have lower left corner as reference point.

        local.x += image.rectTransform.pivot.x * rect.width;

        local.y += image.rectTransform.pivot.y * rect.height;

 

        float u = local.x / rect.width;

        float v = local.y / rect.height;

 

        try

        {

            if(!reversed)

                return sprite.texture.GetPixelBilinear(u, v).a != 0;

            else

                return sprite.texture.GetPixelBilinear(u, v).a == 0;

        }

        catch (UnityException e)

        {

            Debug.LogException(e);

            return true;

        }

    }

}

Paste_Image.png

对图片进行任意变形都支持。只有非透明区域是可以点击的。也可以反过来用，对透明区域可以点击，比如用来做点击遮罩。

using UnityEngine;

using System.Collections;

using UnityEngine.UI;

using System.IO;

 

[DisallowMultipleComponent]

[RequireComponent(typeof(RawImage))]

public class RawImageRaycastFilter : MonoBehaviour, ICanvasRaycastFilter

{

    public bool reversed;

 

    private RawImage rawImage;

 

    void OnEnable()

    {

        rawImage = GetComponent<RawImage>();

    }

 

    public bool IsRaycastLocationValid(Vector2 screenPoint, Camera eventCamera)

    {

        if (!enabled)

            return true;

 

        Texture2D texture = rawImage.texture as Texture2D;

        if (texture == null)

            return true;

 

        Vector2 local;

        RectTransformUtility.ScreenPointToLocalPointInRectangle(rawImage.rectTransform, screenPoint, eventCamera, out local);

 

        Rect rect = rawImage.rectTransform.rect;

 

        // Convert to have lower left corner as reference point.

        local.x += rawImage.rectTransform.pivot.x * rect.width;

        local.y += rawImage.rectTransform.pivot.y * rect.height;

 

        Rect uvRect = rawImage.uvRect;

        float u = local.x / rect.width * uvRect.width + uvRect.x;

        float v = local.y / rect.height * uvRect.height + uvRect.y;

 

        try

        {

            if (!reversed)

                return texture.GetPixelBilinear(u, v).a != 0;

            else

                return texture.GetPixelBilinear(u, v).a == 0;

        }

        catch (UnityException e)

        {

            Debug.LogException(e);

            return true;

        }

    }

}