适应屏幕全屏拉伸

适应屏幕全屏拉伸

Assets/TEngine/Runtime/UI/Extend/UIBackgroundImageStretch.cs

@@ -0,0 +1,18 @@
+using UnityEngine;
+
+namespace TEngine
+{
+    /// <summary>
+    /// 背景图片等比拉伸
+    /// </summary>
+    public class UIBackgroundImageStretch : MonoBehaviour
+    {
+        public bool m_noClip;
+
+        private void Start()
+        {
+            var imageRect = GetComponent<RectTransform>();
+            UIStretchUtil.Instance.DoStretch(imageRect, m_noClip);
+        }
+    }
+}

Assets/TEngine/Runtime/UI/Extend/UIStretchUtil.cs

@@ -0,0 +1,77 @@
+using UnityEngine;
+using UnityEngine.UI;
+
+namespace TEngine
+{
+    public class UIStretchUtil : TSingleton<UIStretchUtil>
+    {
+        private bool m_isInit;
+        private Vector2 m_canvasSize;
+        private float m_screenAspect;
+
+        public bool Init()
+        {
+            var goRoot = GameObject.Find("UIRoot/Canvas");
+            if (goRoot == null)
+            {
+                TLogger.LogError("找不到 goRoot");
+                return false;
+            }
+            var canvasScaler = goRoot.GetComponent<CanvasScaler>();
+            if (canvasScaler == null)
+            {
+                TLogger.LogError("找不到 CanvasScaler");
+                return false;
+            }
+
+            m_screenAspect = Screen.width / (float)Screen.height;
+            float designScale = canvasScaler.referenceResolution.x / canvasScaler.referenceResolution.y;
+            if (m_screenAspect > designScale)
+            {
+                //Match 以 Height 为标准
+                m_canvasSize.y = canvasScaler.referenceResolution.y;
+                m_canvasSize.x = m_canvasSize.y * Screen.width / Screen.height;
+            }
+            else
+            {
+                //Match 以 Weight 为标准
+                m_canvasSize.x = canvasScaler.referenceResolution.x;
+                m_canvasSize.y = m_canvasSize.x * Screen.height / Screen.width;
+            }
+            //BLogger.Error("referenceResolution = "+ canvasScaler.referenceResolution);
+            //BLogger.Error("m_canvasSize = " + m_canvasSize);
+
+            m_isInit = true;
+            return true;
+        }
+
+        public void DoStretch(RectTransform rectTransform, bool noClip)
+        {
+            if (!m_isInit)
+            {
+                if (!Init())
+                {
+                    return;
+                }
+            }
+            if (rectTransform != null && rectTransform.sizeDelta.x > 0 && rectTransform.sizeDelta.y > 0)
+            {
+                Vector2 rectSize = rectTransform.sizeDelta;
+                var rectAspect = rectSize.x / rectSize.y;
+                if (!noClip && rectAspect > m_screenAspect ||
+                    noClip && rectAspect < m_screenAspect)
+                {
+                    //以高为标准
+                    float scale = m_canvasSize.y / rectSize.y;
+                    rectTransform.localScale = new Vector3(scale, scale, 1f);
+                }
+                else
+                {
+                    //以宽为标准
+                    float scale = m_canvasSize.x / rectSize.x;
+                    rectTransform.localScale = new Vector3(scale, scale, 1f);
+                }
+            }
+        }
+    }
+}