pstats: Show hierarchical parent of collector in flame graph

Only when it's different from the nesting parent, and only if there's room.

pandatool/src/gtk-stats/gtkStatsFlameGraph.cxx

@@ -229,7 +229,7 @@ begin_draw() {
  * indicated location.
  */
 void GtkStatsFlameGraph::
-draw_bar(int depth, int from_x, int to_x, int collector_index) {
+draw_bar(int depth, int from_x, int to_x, int collector_index, int parent_index) {
   double bottom = get_ysize() - depth * _pixel_scale * 5;
   double top = bottom - _pixel_scale * 5;
 
@@ -257,18 +257,32 @@ draw_bar(int depth, int from_x, int to_x, int collector_index) {
       int right = std::min(to_x, get_xsize()) - _pixel_scale / 2;
 
       const PStatClientData *client_data = GtkStatsGraph::_monitor->get_client_data();
-      const std::string &name = client_data->get_collector_name(collector_index);
+      const PStatCollectorDef &def = client_data->get_collector_def(collector_index);
 
       // Choose a suitable foreground color.
       LRGBColor fg = get_collector_text_color(collector_index, is_highlighted);
       cairo_set_source_rgb(_cr, fg[0], fg[1], fg[2]);
 
-      PangoLayout *layout = gtk_widget_create_pango_layout(_graph_window, name.c_str());
+      PangoLayout *layout = gtk_widget_create_pango_layout(_graph_window, def._name.c_str());
       pango_layout_set_attributes(layout, _pango_attrs);
       pango_layout_set_ellipsize(layout, PANGO_ELLIPSIZE_END);
       pango_layout_set_width(layout, (right - left) * PANGO_SCALE);
       pango_layout_set_height(layout, -1);
 
+      if (!pango_layout_is_ellipsized(layout)) {
+        // We have room for more.  Show the collector's actual parent, if it's
+        // different than the block it's shown above.
+        if (def._parent_index > 0 && def._parent_index != parent_index) {
+          const PStatCollectorDef &parent_def = client_data->get_collector_def(def._parent_index);
+          std::string long_name = parent_def._name + ":" + def._name;
+          pango_layout_set_text(layout, long_name.c_str(), long_name.size());
+          if (pango_layout_is_ellipsized(layout)) {
+            // Nope, it's too long, go back.
+            pango_layout_set_text(layout, def._name.c_str(), def._name.size());
+          }
+        }
+      }
+
       int width, height;
       pango_layout_get_pixel_size(layout, &width, &height);
 

pandatool/src/gtk-stats/gtkStatsFlameGraph.h

@@ -46,7 +46,8 @@ protected:
 
   void clear_region();
   virtual void begin_draw();
-  virtual void draw_bar(int depth, int from_x, int to_x, int collector_index);
+  virtual void draw_bar(int depth, int from_x, int to_x,
+                        int collector_index, int parent_index);
   virtual void end_draw();
   virtual void idle();
 

pandatool/src/pstatserver/pStatFlameGraph.cxx

@@ -347,7 +347,7 @@ begin_draw() {
  * indicated location.
  */
 void PStatFlameGraph::
-draw_bar(int depth, int from_x, int to_x, int collector_index) {
+draw_bar(int depth, int from_x, int to_x, int collector_index, int parent_index) {
 }
 
 /**
@@ -572,7 +572,7 @@ r_draw_level(const StackLevel &level, int depth, double offset) {
 
     // No need to recurse if the bars have become smaller than a pixel.
     if (to_x > from_x) {
-      draw_bar(depth, from_x, to_x, child._collector_index);
+      draw_bar(depth, from_x, to_x, child._collector_index, level._collector_index);
       r_draw_level(child, depth + 1, offset);
     }
 

pandatool/src/pstatserver/pStatFlameGraph.h

@@ -70,7 +70,8 @@ protected:
   virtual void normal_guide_bars();
 
   virtual void begin_draw();
-  virtual void draw_bar(int depth, int from_x, int to_x, int collector_index);
+  virtual void draw_bar(int depth, int from_x, int to_x,
+                        int collector_index, int parent_index);
   virtual void end_draw();
   virtual void idle();
 

pandatool/src/win-stats/winStatsFlameGraph.cxx

@@ -232,7 +232,7 @@ begin_draw() {
  * indicated location.
  */
 void WinStatsFlameGraph::
-draw_bar(int depth, int from_x, int to_x, int collector_index) {
+draw_bar(int depth, int from_x, int to_x, int collector_index, int parent_index) {
   int bottom = get_ysize() - 1 - depth * _pixel_scale * 5;
   int top = bottom - _pixel_scale * 5;
 
@@ -263,11 +263,34 @@ draw_bar(int depth, int from_x, int to_x, int collector_index) {
       SetTextColor(_bitmap_dc, get_collector_text_color(collector_index, is_highlighted));
 
       const PStatClientData *client_data = WinStatsGraph::_monitor->get_client_data();
-      const std::string &name = client_data->get_collector_name(collector_index);
-
-      RECT rect = {left, top, right, bottom};
-      DrawText(_bitmap_dc, name.data(), name.size(),
-               &rect, DT_LEFT | DT_END_ELLIPSIS | DT_SINGLELINE | DT_VCENTER);
+      const PStatCollectorDef &def = client_data->get_collector_def(collector_index);
+
+      SIZE size;
+      GetTextExtentPoint32(_bitmap_dc, def._name.data(), def._name.size(), &size);
+
+      if (size.cx < right - left) {
+        // We have room for more.  Show the collector's actual parent, if it's
+        // different than the block it's shown above.
+        if (def._parent_index > 0 && def._parent_index != parent_index) {
+          const PStatCollectorDef &parent_def = client_data->get_collector_def(def._parent_index);
+          std::string long_name = parent_def._name + ":" + def._name;
+
+          SIZE long_size;
+          GetTextExtentPoint32(_bitmap_dc, long_name.data(), long_name.size(), &long_size);
+          if (long_size.cx < right - left) {
+            TextOut(_bitmap_dc, left, top + (bottom - top - long_size.cy) / 2,
+                    long_name.data(), long_name.length());
+            return;
+          }
+        }
+        TextOut(_bitmap_dc, left, top + (bottom - top - size.cy) / 2,
+                def._name.data(), def._name.length());
+      } else {
+        // Let Windows figure out how to fit it, with ellipsis if necessary.
+        RECT rect = {left, top, right, bottom};
+        DrawText(_bitmap_dc, def._name.data(), def._name.size(),
+                 &rect, DT_LEFT | DT_END_ELLIPSIS | DT_SINGLELINE | DT_VCENTER);
+      }
     }
   }
 }

pandatool/src/win-stats/winStatsFlameGraph.h

@@ -47,7 +47,8 @@ protected:
 
   void clear_region();
   virtual void begin_draw();
-  virtual void draw_bar(int depth, int from_x, int to_x, int collector_index);
+  virtual void draw_bar(int depth, int from_x, int to_x,
+                        int collector_index, int parent_index);
   virtual void end_draw();
   virtual void idle();