Initial Commit

Library/PackageCache/com.unity.ugui@1.0.0/Runtime/EventSystem/UIElements/PanelRaycaster.cs

@@ -0,0 +1,137 @@
+using System;
+using System.Collections.Generic;
+using System.Runtime.InteropServices;
+using UnityEngine.EventSystems;
+
+namespace UnityEngine.UIElements
+{
+#if PACKAGE_UITOOLKIT
+    /// <summary>
+    /// A derived BaseRaycaster to raycast against UI Toolkit panel instances at runtime.
+    /// </summary>
+    [AddComponentMenu("UI Toolkit/Panel Raycaster (UI Toolkit)")]
+    public class PanelRaycaster : BaseRaycaster, IRuntimePanelComponent
+    {
+        private BaseRuntimePanel m_Panel;
+
+        /// <summary>
+        /// The panel that this component relates to. If panel is null, this component will have no effect.
+        /// Will be set to null automatically if panel is Disposed from an external source.
+        /// </summary>
+        public IPanel panel
+        {
+            get => m_Panel;
+            set
+            {
+                var newPanel = (BaseRuntimePanel)value;
+                if (m_Panel != newPanel)
+                {
+                    UnregisterCallbacks();
+                    m_Panel = newPanel;
+                    RegisterCallbacks();
+                }
+            }
+        }
+
+        void RegisterCallbacks()
+        {
+            if (m_Panel != null)
+            {
+                m_Panel.destroyed += OnPanelDestroyed;
+            }
+        }
+
+        void UnregisterCallbacks()
+        {
+            if (m_Panel != null)
+            {
+                m_Panel.destroyed -= OnPanelDestroyed;
+            }
+        }
+
+        void OnPanelDestroyed()
+        {
+            panel = null;
+        }
+
+        private GameObject selectableGameObject => m_Panel?.selectableGameObject;
+
+        public override int sortOrderPriority => (int)(m_Panel?.sortingPriority ?? 0f);
+        public override int renderOrderPriority => ConvertFloatBitsToInt(m_Panel?.sortingPriority ?? 0f);
+
+        public override void Raycast(PointerEventData eventData, List<RaycastResult> resultAppendList)
+        {
+            if (m_Panel == null)
+                return;
+
+            var eventPosition = Display.RelativeMouseAt(eventData.position);
+            var displayIndex = m_Panel.targetDisplay;
+
+            var originalEventPosition = eventPosition;
+            if (eventPosition != Vector3.zero)
+            {
+                // We support multiple display and display identification based on event position.
+
+                int eventDisplayIndex = (int)eventPosition.z;
+
+                // Discard events that are not part of this display so the user does not interact with multiple displays at once.
+                if (eventDisplayIndex != displayIndex)
+                    return;
+            }
+            else
+            {
+                // The multiple display system is not supported on all platforms, when it is not supported the returned position
+                // will be all zeros so when the returned index is 0 we will default to the event data to be safe.
+                eventPosition = eventData.position;
+
+                // We dont really know in which display the event occured. We will process the event assuming it occured in our display.
+            }
+
+            var position = eventPosition;
+            var delta = eventData.delta;
+
+            float h = Screen.height;
+            if (displayIndex > 0 && displayIndex < Display.displays.Length)
+            {
+                h = Display.displays[displayIndex].systemHeight;
+            }
+
+            position.y = h - position.y;
+            delta.y = -delta.y;
+
+            if (!m_Panel.ScreenToPanel(position, delta, out var panelPosition, out _))
+                return;
+
+            var pick = m_Panel.Pick(panelPosition);
+            if (pick == null)
+                return;
+
+            resultAppendList.Add(new RaycastResult
+            {
+                gameObject = selectableGameObject,
+                module = this,
+                screenPosition = eventPosition,
+                displayIndex = m_Panel.targetDisplay,
+            });
+        }
+
+        public override Camera eventCamera => null;
+
+
+        [StructLayout(LayoutKind.Explicit, Size = sizeof(int))]
+        private struct FloatIntBits
+        {
+            [FieldOffset(0)]
+            public float f;
+            [FieldOffset(0)]
+            public int i;
+        }
+
+        private static int ConvertFloatBitsToInt(float f)
+        {
+            FloatIntBits bits = new FloatIntBits {f = f};
+            return bits.i;
+        }
+    }
+#endif
+}