Collision detection performance: flat pair cache, no worker spin, wider threading

code/cmdline/cmdline.cpp

@@ -268,6 +268,7 @@ Flag exe_params[] =
 	{ "-reparse_mainhall",	"Reparse mainhall.tbl when loading halls",	false,	0,									EASY_DEFAULT,					"Dev Tool",		"http://www.hard-light.net/wiki/index.php/Command-Line_Reference#-reparse_mainhall", },
 	{ "-noninteractive",	"Disables interactive dialogs",				true,	0,									EASY_DEFAULT,					"Dev Tool",		"http://www.hard-light.net/wiki/index.php/Command-Line_Reference#-noninteractive", },
 	{ "-benchmark_mode",	"Puts the game into benchmark mode",		true,	0,									EASY_DEFAULT,					"Dev Tool",		"http://www.hard-light.net/wiki/index.php/Command-Line_Reference#-benchmark_mode", },
+	{ "-collision_bench",	"Benchmark N frames of collision",			true,	0,									EASY_DEFAULT,					"Dev Tool",		"http://www.hard-light.net/wiki/index.php/Command-Line_Reference#-collision_bench", },
 	{ "-profile_frame_time","Profile frame time",						true,	0,									EASY_DEFAULT,					"Dev Tool",		"http://www.hard-light.net/wiki/index.php/Command-Line_Reference#-profile_frame_time", },
 	{ "-profile_write_file", "Write profiling information to file",		true,	0,									EASY_DEFAULT,					"Dev Tool",		"http://www.hard-light.net/wiki/index.php/Command-Line_Reference#-profile_write_file", },
 	{ "-json_profiling",	"Generate JSON profiling output",			true,	0,									EASY_DEFAULT,					"Dev Tool",		"http://www.hard-light.net/wiki/index.php/Command-Line_Reference#-json_profiling", },
@@ -522,6 +523,7 @@ cmdline_parm frame_profile_write_file("-profile_write_file", NULL, AT_NONE); //
 cmdline_parm no_unfocused_pause_arg("-no_unfocused_pause", NULL, AT_NONE); //Cmdline_no_unfocus_pause
 cmdline_parm retail_time_compression_range_arg("-orig_speedx_range", NULL, AT_NONE); //Cmdline_retail_time_compression_range
 cmdline_parm benchmark_mode_arg("-benchmark_mode", NULL, AT_NONE); //Cmdline_benchmark_mode
+cmdline_parm collision_bench_arg("-collision_bench", NULL, AT_INT); //Cmdline_collision_bench
 cmdline_parm pilot_arg("-pilot", nullptr, AT_STRING); //Cmdline_pilot
 cmdline_parm noninteractive_arg("-noninteractive", NULL, AT_NONE); //Cmdline_noninteractive
 cmdline_parm json_profiling("-json_profiling", NULL, AT_NONE); //Cmdline_json_profiling
@@ -564,6 +566,7 @@ bool Cmdline_profile_write_file = false;
 bool Cmdline_no_unfocus_pause = false;
 bool Cmdline_retail_time_compression_range = false;
 bool Cmdline_benchmark_mode = false;
+int Cmdline_collision_bench = 0;
 const char *Cmdline_pilot = nullptr;
 bool Cmdline_noninteractive = false;
 bool Cmdline_json_profiling = false;
@@ -2308,6 +2311,11 @@ bool SetCmdlineParams()
 		Cmdline_benchmark_mode = true;
 	}
 
+	if (collision_bench_arg.found())
+	{
+		Cmdline_collision_bench = collision_bench_arg.get_int();
+	}
+
 	if (pilot_arg.found())
 	{
 		Cmdline_pilot = pilot_arg.str();

code/cmdline/cmdline.h

@@ -147,6 +147,7 @@ extern bool Cmdline_profile_write_file;
 extern bool Cmdline_no_unfocus_pause;
 extern bool Cmdline_retail_time_compression_range;
 extern bool Cmdline_benchmark_mode;
+extern int Cmdline_collision_bench;
 extern const char *Cmdline_pilot;
 extern bool Cmdline_noninteractive;
 extern bool Cmdline_json_profiling;

code/debris/debris.cpp

@@ -916,7 +916,7 @@ void debris_hit(object *debris_obj, object * /*other_obj*/, vec3d *hitpos, float
  * NOTE: debris_hit_info pointer NULL for debris:weapon collision, otherwise debris:ship collision.
  * @return true if hit, else return false.
  */
-int debris_check_collision(object *pdebris, object *other_obj, vec3d *hitpos, collision_info_struct *debris_hit_info, vec3d* hitNormal)
+int debris_check_collision(object *pdebris, object *other_obj, vec3d *hitpos, collision_info_struct *debris_hit_info, vec3d* hitNormal, mc_info* out_mc)
 {
 	mc_info	mc;
 
@@ -956,9 +956,14 @@ int debris_check_collision(object *pdebris, object *other_obj, vec3d *hitpos, co
 			}
 		}
 
-		weapon *wp = &Weapons[other_obj->instance];
-		wp->collisionInfo = new mc_info;	// The weapon will free this memory later
-		*wp->collisionInfo = mc;
+		if (out_mc != nullptr) {
+			// Caller wants the result to stash on the weapon itself, on the main thread.
+			*out_mc = mc;
+		} else {
+			weapon *wp = &Weapons[other_obj->instance];
+			wp->collisionInfo = new mc_info;	// The weapon will free this memory later
+			*wp->collisionInfo = mc;
+		}
 
 		return mc.num_hits;
 	}

code/debris/debris.h

@@ -70,6 +70,7 @@ typedef struct debris {
 extern	SCP_vector<debris> Debris;
 
 struct collision_info_struct;
+struct mc_info;
 
 void debris_init();
 void debris_render(object * obj, model_draw_list *scene);
@@ -88,7 +89,10 @@ void debris_create_set_velocity(const debris *db, const ship *source_shipp, cons
 // Fire scripting hook after debris creation
 void debris_create_fire_hook(object *obj, object *source_obj);
 
-int debris_check_collision( object * obj, object * other_obj, vec3d * hitpos, collision_info_struct *debris_hit_info=NULL, vec3d* hitnormal = NULL );
+// out_mc, when given, receives the raw model collision result instead of it being stashed
+// directly on the weapon.  The threaded collision path needs that write deferred to the main
+// thread, so the caller does it during post-processing.
+int debris_check_collision( object * obj, object * other_obj, vec3d * hitpos, collision_info_struct *debris_hit_info=NULL, vec3d* hitnormal = NULL, mc_info* out_mc = nullptr );
 void debris_hit( object * debris_obj, object * other_obj, vec3d * hitpos, float damage, vec3d* force );
 
 void debris_add_to_hull_list(debris *db);

code/model/modelcollide.cpp

@@ -19,6 +19,7 @@
 #include "model/model.h"
 #include "model/modelrender.h"
 #include "model/modelsinc.h"
+#include "object/collideprofile.h"
 #include "render/3d.h"
 #include "tracing/Monitor.h"
 #include "tracing/tracing.h"
@@ -306,6 +307,7 @@ static void mc_check_sphereline_face( int nv, vec3d ** verts, vec3d * plane_pnt,
 		// check each edge to see if we hit, find the closest edge
 		// Mc->hit_dist stores the best edge time of *all* faces
 		float sphere_time;
+		COLLISION_PROF_INC(sphereline_edge_tests);
 		if ( fvi_polyedge_sphereline(&hit_point, &Mc_p0, &Mc_direction, Mc->radius, nv, verts, &sphere_time)) {
 			Assert( sphere_time >= 0.0f );
 			/*
@@ -389,6 +391,8 @@ void model_collide_bsp_poly(bsp_collision_tree *tree, int leaf_index)
 	vec3d *points[TMAP_MAX_VERTS];
 
 	while ( tested_leaf >= 0 ) {
+		COLLISION_PROF_INC(bsp_leaf_tests);
+
 		bsp_collision_leaf *leaf = &tree->leaf_list[tested_leaf];
 
 		bool flat_poly = false;
@@ -439,6 +443,8 @@ void model_collide_bsp(bsp_collision_tree *tree, int node_index)
 		return;
 	}
 
+	COLLISION_PROF_INC(bsp_node_visits);
+
 	bsp_collision_node *node = &tree->node_list[node_index];
 	vec3d hitpos;
 
@@ -1127,6 +1133,7 @@ int model_collide(mc_info *mc_info_obj)
 	Mc = mc_info_obj;
 
 	MONITOR_INC(NumFVI,1);
+	COLLISION_PROF_INC(model_collide_calls);
 
 	Mc->num_hits = 0;				// How many collisions were found
 	Mc->shield_hit_tri = -1;	// Assume we won't hit any shield polygons