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+[video output=day639 member=cmuratori stream_platform=twitch stream_username=handmade_hero  project=code title="Drawing Debug Diagrams" vod_platform=youtube id=-3XleCNqp1s annotator=Miblo]
+[0:00][Recap and set the stage for the day][:"debug system" :speech]
+[1:28][Conditionally define HANDMADE_DIAGRAMS to HANDMADE_INTERNAL][:"debug system"]
+[2:01][Prepare to draw our diagrams][:"debug system" :research]
+[3:21][Demo the debug overlays and plan our diagram drawing and filtering][:"debug system" :run]
+[9:31][Determine to move the entity :"debug visualisation" into the diagramming system][:"debug system" :research]
+[11:18][Change MoveEntity(), RefineVoxelPlacement() and UpdateBest() to use our diagramming system, introducing a version of DIAGRAM_Color() that takes R, G and B separately][:"debug system"]
+[17:41][Our old :"debug visualisation" is gone][:run]
+[18:12][Force AddPlayer() to let the glove pass our diagramming filter][:"debug system"]
+[19:41][Hit an assertion on DEBUG_RECORD_ALLOCATION() via a DIAGRAM_Text() call in ShapesCollide()][:"debug system" :memory :run]
+[20:59][Investigate our DEBUG_RECORD_ALLOCATION() assertion hit][:"debug system" :memory :research]
+[22:02][Try disabling the diagramming in ShapesCollide()][:"debug system"]
+[22:27][No longer hit that DEBUG_RECORD_ALLOCATION() assertion][:"debug system" :memory :run]
+[23:04][Add an assertion in RenderDiagrams()][:"debug visualisation"]
+[23:58][Never hit that assertion in RenderDiagrams()][:"debug visualisation" :run]
+[24:06][Make UpdateAndRenderWorld() call RenderDiagrams()][:"debug visualisation"]
+[25:04][Implement RenderDiagrams()][:"debug visualisation"]
+[30:19][Consider not buffering the diagrams][:"debug visualisation" :research]
+[32:31][Continue to implement RenderDiagrams()][:"debug visualisation"]
+[33:52][Our glove's :collision diagrams are not drawn][:"debug visualisation" :run]
+[34:05][Quickly sanity check the diagramming code][:"debug visualisation" :research]
+[34:32][Make RenderDiagrams() reset the Current diagram_attributes upon finishing the Diagram_Box case][:"debug visualisation"]
+[35:06][Step through RenderDiagrams()][:"debug visualisation" :run]
+[38:01][Our glove's :collision diagrams are drawn after all, in -Od][:"debug visualisation" :run]
+[38:46][Our glove's :collision diagrams are also drawn in -O2][:"debug visualisation" :run]
+[39:04][Decrease Sticky.Thick from 0.1f to 0.01f in RenderDiagrams()][:"debug visualisation" :run]
+[39:22][Our diagramming system is in action][:"debug visualisation" :run]
+[40:19][Implement the Diagram_Line case in RenderDiagrams()][:"debug visualisation"]
+[42:14][Change the v3 Color in diagram_attributes to be a v4, augmenting diagram_entry with separate Color and Thick values][:"data structure" :"debug system"]
+[43:46][Implement the Diagram_Point case in RenderDiagrams()][:"debug visualisation"]
+[45:15][Reacquaint ourselves with our text :rendering][:font :research]
+[50:30][Fix RenderDiagrams() to pass RenderGroup->WhiteTexture to PushCube()][:"debug visualisation"]
+[51:16][Enable diagramming in ShapesCollide() when its Result is true][:collision :"debug visualisation"]
+[52:24][Try out our collision-based diagramming][:collision :"debug visualisation" :run]
+[53:02][Consider putting :filtering into the system][:"debug visualisation" :research]
+[54:10][Diagramming in The Witness: Capturing diagrams over multiple frames][:collision :"debug visualisation" :run]
+[56:57][Interpret our collision-based diagramming][:collision :"debug visualisation" :run]
+[59:39][Determine to add a "Capture" button to remember diagrams, which we may then "Step" through][:collision :"debug visualisation" :run]
+[1:00:57][Augment diagram_group with a Captured boolean, introducing DIAGRAM_Capture()][:"data structure" :"debug system"]
+[1:03:56][Add a "Capture" / "Resume" button in CollisionEditor(), introducing DIAGRAM_IsCaptured()][:"debug system" :ui]
+[1:07:10][Try out our "Capture" button][:"debug visualisation" :run :ui]
+[1:08:32][Remove SingleStep and StepLatch from game_mode_world][:"data structure" :"debug system"]
+[1:09:26][@Molly][Meow][:speech]
+[1:11:49][Reinstate SingleStep and StepLatch in game_mode_world][:"data structure" :"debug system"]
+[1:12:17][Try "Single Stepping"][:"debug visualisation" :run :ui]
+[/video]