Allow mods to tune generic debris generation (#7027)

* Allow 'No Impact Debris' to also apply to explosions

The ship/subsystem flag `no impact debris` prevents the default debris shards from spawning, which is very valuable especially now that impact effects can be completely customized via the -particles table. Now that particle effects are also an option for ship and subsystems explosions, it is also invaluable to have the ability to turn off the spawning of shards when either of those explosions happen.

This PR uses the same flag of `no impact debris` and simply does not spawn the default shards for ship explosions or subsystem explosions of that flag is enabled. I thought about adding two new flags, but that would add to the flag clutter, and most folks who use these flags to turn off impacts I would estimate also want them off for actual explosions. Also, a new flag called `no explosion debris` would likely be confusing, so if a new flag were to be added it should be called something like `no default explosion debris shards` or something. Overall I've opted with the simpler and cleaner solution to just have it all under the impact flags. If two new flags are desired though I can easily add them.

Tested and works as expected.

* throw clang a bone

* use two different flags

* update flag name

* typo and logic fix

* allow custom generic debris to always work

* update to better methods

* cleanup logic

* clang

Author: wookieejedi

code/debris/debris.cpp

@@ -1305,14 +1305,21 @@ void create_generic_debris(object* ship_objp, const vec3d* pos, float min_num_de
 	if (ship_objp->type != OBJ_SHIP)
 		return;
 
+	// determine if using custom or non-custom generic debris
+	int model_num = use_ship_debris ? Ship_info[Ships[ship_objp->instance].ship_info_index].generic_debris_model_num : -1;
+
+	// if using non-custom generic debris, then bail early if that kind of debris is not allowed --wookeejedi
+	if ( (model_num < 0) && (Disable_all_noncustom_generic_debris) ) {
+		return;
+	}
+
 	float num_debris = frand_range(min_num_debris, max_num_debris);
 
 	num_debris *= (Detail.num_small_debris + 0.5f) / 4.5f;
 
 	vec3d create_pos = *pos;
 	for (int i = 0; i < num_debris; i++) {
-		int model_num = use_ship_debris ? Ship_info[Ships[ship_objp->instance].ship_info_index].generic_debris_model_num : -1;
-		debris_create(ship_objp, model_num, -1, &create_pos, pos, 0, speed_mult);
+		debris_create(ship_objp, model_num, -1, &create_pos, pos, false, speed_mult);
 	}
 }
 

code/mod_table/mod_table.cpp

@@ -162,6 +162,7 @@ bool Disabled_or_disrupted_engines_silent;
 std::array<std::tuple<float, float>, 6> Fred_spacemouse_nonlinearity;
 bool Randomize_particle_rotation;
 bool Disable_shield_effects;
+bool Disable_all_noncustom_generic_debris;
 bool Calculate_subsystem_hitpoints_after_parsing;
 bool Disable_internal_loadout_restoration_system;
 bool Contrails_use_absolute_speed;
@@ -995,6 +996,10 @@ void parse_mod_table(const char *filename)
 				stuff_boolean(&Disable_shield_effects);
 			}
 
+			if (optional_string("$Disable all non-custom generic debris:")) {
+				stuff_boolean(&Disable_all_noncustom_generic_debris);
+			}
+
 			optional_string("#NETWORK SETTINGS");
 
 			if (optional_string("$FS2NetD port:")) {
@@ -1823,6 +1828,7 @@ void mod_table_reset()
 			std::tuple<float, float>{ 1.0f, 1.0f }
 		}};
 	Randomize_particle_rotation = false;
+	Disable_all_noncustom_generic_debris = false;
 	Disable_shield_effects = false;
 	Calculate_subsystem_hitpoints_after_parsing = false;
 	Disable_internal_loadout_restoration_system = false;

code/mod_table/mod_table.h

@@ -177,6 +177,7 @@ extern bool Disabled_or_disrupted_engines_silent;
 extern std::array<std::tuple<float, float>, 6> Fred_spacemouse_nonlinearity;
 extern bool Randomize_particle_rotation;
 extern bool Disable_shield_effects;
+extern bool Disable_all_noncustom_generic_debris;
 extern bool Calculate_subsystem_hitpoints_after_parsing;
 extern bool Disable_internal_loadout_restoration_system;
 extern bool Contrails_use_absolute_speed;

code/model/model_flags.h

@@ -68,7 +68,8 @@ namespace Model {
         No_autorepair_if_disabled,	// Inversion of the previous; disallows this particular subsystem if the ship-wide flag is set (MageKing17)
         Share_fire_direction,		// (DahBlount) Whenever the turret fires a beam, make all beams fire in the same direction.
         No_sparks,          // Subsystem does not generate sparks if hit - m!m
-		No_impact_debris,    // Don't spawn the small debris on impact - m!m
+		Disable_all_generic_impact_debris,    // Don't spawn generic debris pieces on impact - m!m
+		Disable_all_generic_explosion_debris, // Don't spawn generic debris pieces on explosion - wookieejedi
 		Hide_turret_from_loadout_stats, // Turret is not accounted for in auto-generated "Turrets" line in the ship loadout window --wookieejedi
 		Turret_distant_firepoint,	//Turret barrel is very long and should be taken into account when aiming -- Kiloku
 		Override_submodel_impact,	// if a weapon impacted a submodel, but this subsystem is within range, the subsystem takes priority -- Goober5000

code/ship/ship.cpp

@@ -353,7 +353,8 @@ flag_def_list_new<Model::Subsystem_Flags> Subsystem_flags[] = {
 	{ "don't autorepair if disabled", Model::Subsystem_Flags::No_autorepair_if_disabled,        true, false },
 	{ "share fire direction",       Model::Subsystem_Flags::Share_fire_direction,               true, false },
 	{ "no damage spew",             Model::Subsystem_Flags::No_sparks,                          true, false },
-	{ "no impact debris",           Model::Subsystem_Flags::No_impact_debris,                   true, false },
+	{ "disable all generic impact debris",    Model::Subsystem_Flags::Disable_all_generic_impact_debris,    true, false },
+	{ "disable all generic explosion debris", Model::Subsystem_Flags::Disable_all_generic_explosion_debris, true, false },
 	{ "hide turret from loadout stats", Model::Subsystem_Flags::Hide_turret_from_loadout_stats, true, false },
 	{ "turret has distant firepoint", Model::Subsystem_Flags::Turret_distant_firepoint,         true, false },
 	{ "override submodel impact",   Model::Subsystem_Flags::Override_submodel_impact,           true, false },
@@ -412,7 +413,8 @@ flag_def_list_new<Info_Flags> Ship_flags[] = {
 	{ "don't clamp max velocity",	Info_Flags::Dont_clamp_max_velocity,	true, false },
 	{ "instantaneous acceleration",	Info_Flags::Instantaneous_acceleration,	true, false },
 	{ "large ship deathroll",		Info_Flags::Large_ship_deathroll,	true, false },
-	{ "no impact debris",			Info_Flags::No_impact_debris,		true, false },
+	{ "disable all generic impact debris",    Info_Flags::Disable_all_generic_impact_debris,    true, false },
+	{ "disable all generic explosion debris", Info_Flags::Disable_all_generic_explosion_debris, true, false },
     // to keep things clean, obsolete options go last
     { "ballistic primaries",		Info_Flags::Ballistic_primaries,	false, false }
 };
@@ -4461,6 +4463,10 @@ static void parse_ship_values(ship_info* sip, const bool is_template, const bool
 				flag_found = true;
 				sip->flags.set(Ship::Info_Flags::Dont_clamp_max_velocity);
 			}
+			if (!stricmp(cur_flag, "no impact debris")) {
+				flag_found = true;
+				sip->flags.set(Ship::Info_Flags::Disable_all_generic_impact_debris);
+			}
 
 			if ( !flag_found && (ship_type_index < 0) )
 				Warning(LOCATION, "Bogus string in ship flags: %s\n", cur_flag);
@@ -5837,7 +5843,25 @@ static void parse_ship_values(ship_info* sip, const bool is_template, const bool
                 SCP_vector<SCP_string> errors;
                 flagset<Model::Subsystem_Flags> tmp_flags;
                 parse_string_flag_list(tmp_flags, Subsystem_flags, Num_subsystem_flags, &errors);
-                
+ 
+				// Map of deprecated strings to their new flags
+				static const SCP_unordered_map<SCP_string, Model::Subsystem_Flags, SCP_string_lcase_hash, SCP_string_lcase_equal_to>
+				deprecated_map = {
+					{"no impact debris", Model::Subsystem_Flags::Disable_all_generic_impact_debris},
+					// { "old name", Model::Subsystem_Flags::New_flag },   // future additions
+				};
+
+				// Walk through errors, remap if deprecated
+				for (auto it = errors.begin(); it != errors.end();) {
+					auto found = deprecated_map.find(*it);
+					if (found != deprecated_map.end()) {
+						tmp_flags.set(found->second);
+						it = errors.erase(it); // remove so no bogus warning
+					} else {
+						++it;
+					}
+				}
+
                 if (optional_string("+noreplace")) {
                     sp->flags |= tmp_flags;
                 }

code/ship/ship_flags.h

@@ -217,7 +217,8 @@ namespace Ship {
 		Instantaneous_acceleration,		// Goober5000
 		Has_display_name,				// Goober5000
 		Large_ship_deathroll,			// Asteroth - big ships dont normally deathroll, this makes them do it!
-		No_impact_debris,				// wookieejedi - Don't spawn the small debris on impact
+		Disable_all_generic_impact_debris,    // wookieejedi - Don't spawn debris on impact
+		Disable_all_generic_explosion_debris, // wookieejedi - Don't spawn debris on explosion
 
 		NUM_VALUES
 	};

code/ship/shipfx.cpp

@@ -285,10 +285,19 @@ void shipfx_blow_off_subsystem(object *ship_objp, ship *ship_p, const ship_subsy
 
 	// create debris shards
     if (!(subsys->flags[Ship::Subsystem_Flags::Vanished]) && !no_explosion) {
-		shipfx_blow_up_model(ship_objp, psub->subobj_num, 50, &subobj_pos, subsys );
+		// default debris shard creation is flag dependent --wookieejedi
+		int num_shards;
+		if (Disable_all_noncustom_generic_debris ||  
+			(Ship_info[ship_p->ship_info_index].flags[Ship::Info_Flags::Disable_all_generic_explosion_debris]) ||
+			(subsys->system_info->flags[Model::Subsystem_Flags::Disable_all_generic_explosion_debris])) {
+			num_shards = 0;
+		} else {
+			num_shards = 50;
+		}
+		shipfx_blow_up_model(ship_objp, psub->subobj_num, num_shards, &subobj_pos, subsys);
 
 		// create live debris objects, if any
-		// TODO:  some MULTIPLAYER implcations here!!
+		// TODO:  some MULTIPLAYER implications here!!
 		shipfx_subsystem_maybe_create_live_debris(ship_objp, ship_p, subsys, exp_center, 1.0f, no_fireballs);
 
 		if (!no_fireballs) {

code/ship/shiphit.cpp

@@ -797,8 +797,8 @@ std::pair<std::optional<ConditionData>, float> do_subobj_hit_stuff(object *ship_
 	if (!global_damage) {
 		auto subsys = ship_get_subsys_for_submodel(ship_p, submodel_num);
 
-		if ( !(Ship_info[ship_p->ship_info_index].flags[Ship::Info_Flags::No_impact_debris]) && 
-			( subsys == nullptr || !(subsys->system_info->flags[Model::Subsystem_Flags::No_impact_debris]) ) ) {
+		if ( !(Ship_info[ship_p->ship_info_index].flags[Ship::Info_Flags::Disable_all_generic_impact_debris]) && 
+			( subsys == nullptr || !(subsys->system_info->flags[Model::Subsystem_Flags::Disable_all_generic_impact_debris]) ) ) {
 			create_generic_debris(ship_objp, hitpos, 1.0f, 5.0f, 1.0f, false);
 		}
 	}
@@ -1855,19 +1855,21 @@ static void ship_vaporize(ship *shipp)
 	object *ship_objp;
 
 	// sanity
-	Assert(shipp != NULL);
-	if(shipp == NULL){
+	Assert(shipp != nullptr);
+	if (shipp == nullptr) {
 		return;
 	}
 	Assert((shipp->objnum >= 0) && (shipp->objnum < MAX_OBJECTS));
-	if((shipp->objnum < 0) || (shipp->objnum >= MAX_OBJECTS)){
+	if ( (shipp->objnum < 0) || (shipp->objnum >= MAX_OBJECTS) ) {
 		return;
 	}
 	ship_objp = &Objects[shipp->objnum];
 	ship_info* sip = &Ship_info[shipp->ship_info_index];
 
 	// create debris shards
-	create_generic_debris(ship_objp, &ship_objp->pos, (float)sip->generic_debris_spew_num, sip->generic_debris_spew_num * 2.0f, 1.4f, true);
+	if ( !(sip->flags[Ship::Info_Flags::Disable_all_generic_explosion_debris]) ) {
+		create_generic_debris(ship_objp, &ship_objp->pos, (float)sip->generic_debris_spew_num, sip->generic_debris_spew_num * 2.0f, 1.4f, true);
+	}
 }
 
 //	*ship_objp was hit and we've determined he's been killed!  By *other_obj!