From 833c3d37f76945eef29ae93dcba902a9a2832c89 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Fri, 16 Dec 2022 20:13:41 +0100
Subject: [PATCH] gobj: Compute nested vertices separate from internal bounds
 in Geom

This prevents having to recalculate the internal bounds (which may be quite slow to compute, but not actually necessary if there are user bounds present) to get the nested vertices
---
 panda/src/gobj/geom.I   |  3 +++
 panda/src/gobj/geom.cxx | 23 ++++++++++++++++++++---
 panda/src/gobj/geom.h   |  2 ++
 3 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/panda/src/gobj/geom.I b/panda/src/gobj/geom.I
index 3fa32ade36..fb7e858d84 100644
--- a/panda/src/gobj/geom.I
+++ b/panda/src/gobj/geom.I
@@ -379,6 +379,7 @@ calc_tight_bounds(LPoint3 &min_point, LPoint3 &max_point,
  */
 INLINE void Geom::
 mark_internal_bounds_stale(CData *cdata) {
+  cdata->_nested_vertices_stale = true;
   cdata->_internal_bounds_stale = true;
 }
 
@@ -512,6 +513,7 @@ CData() :
   _shade_model(SM_uniform),
   _geom_rendering(0),
   _nested_vertices(0),
+  _nested_vertices_stale(true),
   _internal_bounds_stale(true),
   _bounds_type(BoundingVolume::BT_default)
 {
@@ -527,6 +529,7 @@ CData(GeomVertexData *data) :
   _shade_model(SM_uniform),
   _geom_rendering(0),
   _nested_vertices(0),
+  _nested_vertices_stale(true),
   _internal_bounds_stale(true),
   _bounds_type(BoundingVolume::BT_default)
 {
diff --git a/panda/src/gobj/geom.cxx b/panda/src/gobj/geom.cxx
index 5733c4bee0..624216d38c 100644
--- a/panda/src/gobj/geom.cxx
+++ b/panda/src/gobj/geom.cxx
@@ -1098,9 +1098,9 @@ get_bounds(Thread *current_thread) const {
 int Geom::
 get_nested_vertices(Thread *current_thread) const {
   CDLockedReader cdata(_cycler, current_thread);
-  if (cdata->_internal_bounds_stale) {
+  if (cdata->_nested_vertices_stale) {
     CDWriter cdataw(((Geom *)this)->_cycler, cdata, false);
-    compute_internal_bounds(cdataw, current_thread);
+    compute_nested_vertices(cdataw, current_thread);
     return cdataw->_nested_vertices;
   }
   return cdata->_nested_vertices;
@@ -1468,9 +1468,26 @@ compute_internal_bounds(Geom::CData *cdata, Thread *current_thread) const {
       cdata->_internal_bounds = new BoundingBox;
     }
   }
+  cdata->_internal_bounds_stale = false;
+}
+
+/**
+ * Recomputes the number of nested vertices in this Geom.
+ */
+void Geom::
+compute_nested_vertices(Geom::CData *cdata, Thread *current_thread) const {
+  int num_vertices = 0;
+
+  Primitives::const_iterator pi;
+  for (pi = cdata->_primitives.begin();
+       pi != cdata->_primitives.end();
+       ++pi) {
+    GeomPrimitivePipelineReader reader((*pi).get_read_pointer(current_thread), current_thread);
+    num_vertices += reader.get_num_vertices();
+  }
 
   cdata->_nested_vertices = num_vertices;
-  cdata->_internal_bounds_stale = false;
+  cdata->_nested_vertices_stale = false;
 }
 
 /**
diff --git a/panda/src/gobj/geom.h b/panda/src/gobj/geom.h
index 073805e7ca..986ca5a827 100644
--- a/panda/src/gobj/geom.h
+++ b/panda/src/gobj/geom.h
@@ -185,6 +185,7 @@ private:
 
   INLINE void mark_internal_bounds_stale(CData *cdata);
   void compute_internal_bounds(CData *cdata, Thread *current_thread) const;
+  void compute_nested_vertices(CData *cdata, Thread *current_thread) const;
 
   void do_calc_tight_bounds(LPoint3 &min_point, LPoint3 &max_point,
                             PN_stdfloat &sq_center_dist, bool &found_any,
@@ -327,6 +328,7 @@ private:
 
     CPT(BoundingVolume) _internal_bounds;
     int _nested_vertices;
+    bool _nested_vertices_stale;
     bool _internal_bounds_stale;
     BoundingVolume::BoundsType _bounds_type;
     CPT(BoundingVolume) _user_bounds;