public void Render(VisualTreeAsset vta, Rect r, GUIStyle background)
{
if (Event.current.type != EventType.Repaint || r.width < 100 && r.height < 100)
{
return;
}
bool dirty = false;
if (vta != m_LastTree || !m_LastTree)
{
m_LastTree = vta;
m_Tree = (vta as UnityEngine.UIElements.VisualTreeAsset).CloneTree();
m_Tree.StretchToParentSize();
dirty = true;
}
if (m_Panel == null)
{
m_Panel = UIElementsUtility.FindOrCreatePanel(m_LastTree, ContextType.Editor);
var visualTree = m_Panel.visualTree;
visualTree.pseudoStates |= PseudoStates.Root;
UIElementsEditorUtility.AddDefaultEditorStyleSheets(visualTree);
m_Panel.allowPixelCaching = false;
dirty = true;
}
if (dirty)
{
m_Panel.visualTree.Clear();
m_Panel.visualTree.Add(m_Tree);
}
EditorGUI.DrawRect(r, EditorGUIUtility.kViewBackgroundColor);
m_Panel.visualTree.SetSize(r.size); // We will draw relative to a viewport covering the preview area, so draw at 0,0
m_Panel.visualTree.IncrementVersion(VersionChangeType.Repaint);
var oldState = SavedGUIState.Create();
int clips = GUIClip.Internal_GetCount();
while (clips > 0)
{
GUIClip.Pop();
clips--;
}
float pixelsPerPoint = EditorGUIUtility.pixelsPerPoint;
var desc = new RenderTextureDescriptor((int)(r.width * pixelsPerPoint), (int)(r.height * pixelsPerPoint), RenderTextureFormat.ARGB32, 16);
var rt = RenderTexture.GetTemporary(desc);
var oldRt = RenderTexture.active;
RenderTexture.active = rt;
GL.LoadPixelMatrix(0, rt.width, rt.height, 0);
m_Panel.Repaint(Event.current);
RenderTexture.active = oldRt;
oldState.ApplyAndForget();
GUI.DrawTexture(r, rt);
RenderTexture.ReleaseTemporary(rt);
}
