unity 实战图片挖洞Mask(转载)

转载转载

https://www.cnblogs.com/j349900963/p/8340571.html

截取里面俩代码，可以实现图片挖洞的需求

注意：

hole image 需要 将图片的透明度调整为1

public class Hole : Mask
{
    public override bool IsRaycastLocationValid(Vector2 sp, Camera eventCamera)
    {
        if (!isActiveAndEnabled)
            return true;
 
        return !RectTransformUtility.RectangleContainsScreenPoint(rectTransform, sp, eventCamera);
    }
}

　　

public class HoleImage : Image {
    public override Material GetModifiedMaterial(Material baseMaterial)
    {
        var toUse = baseMaterial;
 
        if (m_ShouldRecalculateStencil)
        {
            var rootCanvas = MaskUtilities.FindRootSortOverrideCanvas(transform);
            m_StencilValue = maskable ? MaskUtilities.GetStencilDepth(transform, rootCanvas) : 0;
            m_ShouldRecalculateStencil = false;
        }
 
        // if we have a enabled Mask component then it will
        // generate the mask material. This is an optimisation
        // it adds some coupling between components though :(
        Mask maskComponent = GetComponent<Mask>();
        if (m_StencilValue > 0 && (maskComponent == null || !maskComponent.IsActive()))
        {
            var maskMat = StencilMaterial.Add(toUse, (1 << m_StencilValue) - 1, StencilOp.Keep, CompareFunction.NotEqual, ColorWriteMask.All, (1 << m_StencilValue) - 1, 0);
            StencilMaterial.Remove(m_MaskMaterial);
            m_MaskMaterial = maskMat;
            toUse = m_MaskMaterial;
        }
        return toUse;
    }
}