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Rect内でボタンのタッチ判定をする方法
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ScreenPointToLocalPointInRectangleを使う
if (Input.GetKeyDown(KeyCode.Mouse0))
{
Vector2 localPoint;
RectTransformUtility.ScreenPointToLocalPointInRectangle(rectTransform, Input.mousePosition, Camera.main, out localPoint);
if (rectTransform.rect.Contains(localPoint))
{
// 処理
}
}