From 115cdd268e6c3bee9527958c594e58604e30532e Mon Sep 17 00:00:00 2001
From: codereader <greebo@angua.at>
Date: Sun, 31 Oct 2021 14:09:06 +0100
Subject: [PATCH] #5795: Only run tests in evaluateViewDependent() if the
 visibility of any face actually changed. This can be the case either by
 forcing a brush to be visible or by its material filter status.

---
 libs/scene/Node.h               |  2 +-
 radiantcore/brush/BrushNode.cpp | 24 +++++++++++++++++++-----
 radiantcore/brush/BrushNode.h   |  9 ++++++++-
 radiantcore/brush/Face.cpp      |  9 ++++++++-
 4 files changed, 36 insertions(+), 8 deletions(-)

diff --git a/libs/scene/Node.h b/libs/scene/Node.h
index 5b5e80ea7e..16442fff27 100644
--- a/libs/scene/Node.h
+++ b/libs/scene/Node.h
@@ -196,7 +196,7 @@ class Node :
 
 protected:
     // Set the "forced visible" flag, only to be used internally by subclasses
-	void setForcedVisibility(bool forceVisible, bool includeChildren) override;
+	virtual void setForcedVisibility(bool forceVisible, bool includeChildren) override;
 
 	// Method for subclasses to check whether this node is forcedly visible
 	bool isForcedVisible() const;
diff --git a/radiantcore/brush/BrushNode.cpp b/radiantcore/brush/BrushNode.cpp
index f1837162cf..c61f26a834 100644
--- a/radiantcore/brush/BrushNode.cpp
+++ b/radiantcore/brush/BrushNode.cpp
@@ -15,6 +15,7 @@
 BrushNode::BrushNode() :
 	scene::SelectableNode(),
 	m_brush(*this),
+    _faceVisibilityChanged(true),
 	_selectedPoints(GL_POINTS),
 	_faceCentroidPointsCulled(GL_POINTS),
 	m_viewChanged(false),
@@ -42,6 +43,7 @@ BrushNode::BrushNode(const BrushNode& other) :
 	LitObject(other),
 	Transformable(other),
 	m_brush(*this, other.m_brush),
+    _faceVisibilityChanged(true),
 	_selectedPoints(GL_POINTS),
 	_faceCentroidPointsCulled(GL_POINTS),
 	m_viewChanged(false),
@@ -355,7 +357,7 @@ void BrushNode::renderComponents(RenderableCollector& collector, const VolumeTes
 
 	if (volume.fill() && GlobalSelectionSystem().ComponentMode() == selection::ComponentSelectionMode::Face)
 	{
-		evaluateViewDependent(volume, l2w);
+        updateWireframeVisibility(volume, l2w);
 		collector.addRenderable(*m_brush.m_state_point, _faceCentroidPointsCulled, l2w);
 	}
 	else
@@ -418,11 +420,23 @@ std::size_t BrushNode::getHighlightFlags()
 	return isGroupMember() ? (Highlight::Selected | Highlight::GroupMember) : Highlight::Selected;
 }
 
-void BrushNode::evaluateViewDependent(const VolumeTest& volume, const Matrix4& localToWorld) const
+void BrushNode::onFaceVisibilityChanged()
 {
-	if (!m_viewChanged) return;
+    _faceVisibilityChanged = true;
+}
+
+void BrushNode::setForcedVisibility(bool forceVisible, bool includeChildren)
+{
+    Node::setForcedVisibility(forceVisible, includeChildren);
+ 
+    _faceVisibilityChanged = true;
+}
+
+void BrushNode::updateWireframeVisibility(const VolumeTest& volume, const Matrix4& localToWorld) const
+{
+    if (!_faceVisibilityChanged) return;
 
-	m_viewChanged = false;
+    _faceVisibilityChanged = false;
 
 	// Array of booleans to indicate which faces are visible
 	static bool faces_visible[brush::c_brush_maxFaces];
@@ -503,7 +517,7 @@ void BrushNode::renderWireframe(RenderableCollector& collector, const VolumeTest
 {
 	//renderCommon(collector, volume);
 
-	evaluateViewDependent(volume, localToWorld);
+    updateWireframeVisibility(volume, localToWorld);
 
 	if (m_render_wireframe.m_size != 0)
 	{
diff --git a/radiantcore/brush/BrushNode.h b/radiantcore/brush/BrushNode.h
index 587ba7ff85..f2d5da7d4e 100644
--- a/radiantcore/brush/BrushNode.h
+++ b/radiantcore/brush/BrushNode.h
@@ -42,6 +42,8 @@ class BrushNode :
 	typedef std::vector<brush::VertexInstance> VertexInstances;
 	VertexInstances m_vertexInstances;
 
+    mutable bool _faceVisibilityChanged;
+
 	mutable RenderableWireframe m_render_wireframe;
 
     // Renderable array of vertex and edge points
@@ -168,10 +170,15 @@ class BrushNode :
     // Should only be used by the internal Brush object
     bool facesAreForcedVisible();
 
+    // Will be invoked if one of this brush's faces updates its visibility status
+    void onFaceVisibilityChanged();
+
     void onPostUndo() override;
     void onPostRedo() override;
 
 protected:
+    virtual void setForcedVisibility(bool forceVisible, bool includeChildren) override;
+
 	// Gets called by the Transformable implementation whenever
 	// scale, rotation or translation is changed.
 	void _onTransformationChanged() override;
@@ -192,7 +199,7 @@ class BrushNode :
                               const Matrix4& localToWorld) const;
 
 	void renderClipPlane(RenderableCollector& collector, const VolumeTest& volume) const;
-	void evaluateViewDependent(const VolumeTest& volume, const Matrix4& localToWorld) const;
+	void updateWireframeVisibility(const VolumeTest& volume, const Matrix4& localToWorld) const;
 
 }; // class BrushNode
 typedef std::shared_ptr<BrushNode> BrushNodePtr;
diff --git a/radiantcore/brush/Face.cpp b/radiantcore/brush/Face.cpp
index 6e49f50ce7..9f87930f3f 100644
--- a/radiantcore/brush/Face.cpp
+++ b/radiantcore/brush/Face.cpp
@@ -724,7 +724,14 @@ bool Face::isVisible() const
 
 void Face::updateFaceVisibility()
 {
-    _faceIsVisible = contributes() && getFaceShader().getGLShader()->getMaterial()->isVisible();
+    auto newValue = contributes() && getFaceShader().getGLShader()->getMaterial()->isVisible();
+    
+    // Notify the owning brush if the value changes
+    if (newValue != _faceIsVisible)
+    {
+        _faceIsVisible = newValue;
+        _owner.getBrushNode().onFaceVisibilityChanged();
+    }
 }
 
 sigc::signal<void>& Face::signal_texdefChanged()