Hammerhead, ram ahead

nsv13/code/__DEFINES/overmap.dm

@@ -114,6 +114,11 @@ GLOBAL_LIST_INIT(overmap_impact_sounds, list('nsv13/sound/effects/ship/freespace
 #define MASS_TITAN 150 //40+ Players - Large Capital Ships
 #define MASS_IMMOBILE 200 //Things that should not be moving. See: stations
 
+//Collision stuff
+#define OVERMAP_COLLISION_COOLDOWN 1 SECONDS //! Cooldown between collisions.
+#define OVERMAP_COLLISION_MAGNIFIER 4 //! All collision damage big enough to go into the damage calculation itself is multiplied by this.
+#define HAMMERHEAD_COLLISION_GUARD_ANGLE 55 //! Angle that determines maximum variance of collision angle to ship angle to count as "head" impact.
+
 //Fun tools
 #define SHIELD_NOEFFECT 0 //!Shield failed to absorb hit.
 #define SHIELD_ABSORB 1 //!Shield absorbed hit.

nsv13/code/modules/overmap/fighters/fighters_launcher.dm

@@ -157,7 +157,7 @@
 			linkup()
 
 /obj/structure/fighter_launcher/proc/shake_people(var/obj/structure/overmap/OM)
-	if(OM?.operators.len)
+	if(OM && length(OM.operators))
 		for(var/mob/M in OM.operators)
 			shake_with_inertia(M, 10, 1)
 			to_chat(M, "<span class='warning'>You feel a sudden jolt!</span>")

nsv13/code/modules/overmap/overmap.dm

@@ -31,6 +31,8 @@
 	var/sprite_size = 64 //Pixels. This represents 64x64 and allows for the bullets that you fire to align properly.
 	var/area_type = null //Set the type of the desired area you want a ship to link to, assuming it's not the main player ship.
 	var/impact_sound_cooldown = FALSE //Avoids infinite spamming of the ship taking damage.
+	///Handles cooldown between collisions to avoid certain very bad times :)
+	var/next_collision = 0
 	var/datum/star_system/current_system //What star_system are we currently in? Used for parallax.
 	var/resize = 0 //Factor by which we should shrink a ship down. 0 means don't shrink it.
 	var/list/docking_points = list() //Where we can land on this ship. Usually right at the edge of a z-level.
@@ -1005,3 +1007,14 @@ Proc to spool up a new Z-level for a player ship and assign it a treadmill.
 	if(ftl_drive)
 		return TRUE
 	return FALSE
+
+/**
+ * Handles special modifications or effects an overmap has for collisions.
+ * * other_ship = the ship this collides with.
+ * * impact_powers = the strength of the impact for (this ship, other ship). Done this way because list pointer allows inplace var access.
+ * * impact_angle = The angle of the impact.
+ *
+ * This does NOT return the modified impact powers, as it is not neccessary due to inplace handling!
+ */
+/obj/structure/overmap/proc/spec_collision_handling(obj/structure/overmap/other_ship, list/impact_powers, impact_angle)
+	return

nsv13/code/modules/overmap/physics.dm

@@ -438,6 +438,15 @@ This proc is to be used when someone gets stuck in an overmap ship, gauss, WHATE
 		return
 	return ..()
 
+/**
+ * Handles collision between two overmap objects.
+ * * other = the object collided with.
+ * * c_response = ????
+ * * collision_velocity = UNUSED
+ *
+ * * BEAR IN MIND col_angle and velocity angles go COUNTERCLOCKWISE starting EAST while (overmap) angle itself goes CLOCKWISE starting NORTH!!!!!
+ * * ^ ^ ^ ^ THIS IS REALLY IMPORTANT
+ */
 /obj/structure/overmap/proc/collide(obj/structure/overmap/other, datum/collision_response/c_response, collision_velocity)
 	//No colliders. But we still get a lot of info anyways!
 	if(!c_response)
@@ -452,7 +461,7 @@ This proc is to be used when someone gets stuck in an overmap ship, gauss, WHATE
 		if(((cos(src.velocity.angle() - col_angle) * src_vel_mag) - (cos(other.velocity.angle() - col_angle) * other_vel_mag)) < 0)
 			return
 
-		// Elastic collision equations
+		// Elastic collision equations - I don't feel like rewriting these so I'll just change the damage calculation unrelated to the new velocities :) ~Delta
 		var/new_src_vel_x = ((																			\
 			(src_vel_mag * cos(src.velocity.angle() - col_angle) * (src.mass - other.mass)) +			\
 			(2 * other.mass * other_vel_mag * cos(other.velocity.angle() - col_angle))					\
@@ -473,20 +482,46 @@ This proc is to be used when someone gets stuck in an overmap ship, gauss, WHATE
 			(2 * src.mass * src_vel_mag * cos(src.velocity.angle() - col_angle))						\
 		) / (other.mass + src.mass)) * sin(col_angle) + (other_vel_mag * sin(other.velocity.angle() - col_angle) * sin(col_angle + 90))
 
-		src.velocity._set(new_src_vel_x, new_src_vel_y)
-		other.velocity._set(new_other_vel_x, new_other_vel_y)
+		//New calculations, go!
+
+		//Calculate vector forces when angled towards collision angle.
 
-		var/bonk = src_vel_mag//How much we got bonked
-		var/bonk2 = other_vel_mag //Vs how much they got bonked
-		//Prevent ultra spam.
-		if(!impact_sound_cooldown && (bonk > 2 || bonk2 > 2))
-			bonk *= 5 //The rammer gets an innate penalty, to discourage ramming metas.
-			bonk2 *= 5
-			take_quadrant_hit(bonk, quadrant_impact(other)) //This looks horrible, but trust me, it isn't! Probably!. Armour_quadrant.dm for more info
-			other.take_quadrant_hit(bonk2, quadrant_impact(src)) //This looks horrible, but trust me, it isn't! Probably!. Armour_quadrant.dm for more info
+		var/self_vector_angle_diff = ((col_angle - velocity.angle()) + 360) % 360 //Byond modulo allows negative values as outcome apparently. :)
+		var/self_ramvec = src_vel_mag * cos(self_vector_angle_diff)
 
-			log_game("[key_name(pilot)] has impacted an overmap ship into [other] with velocity [bonk]")
+		var/other_vector_angle_diff = ((col_angle + 180 - other.velocity.angle()) + 360) % 360
+		var/other_ramvec = other_vel_mag * cos(other_vector_angle_diff)
 
+		var/total_force = (self_ramvec + other_ramvec) //Forces combined
+
+		if(world.time >= next_collision && total_force >= 2) //Magic!
+			total_force *= OVERMAP_COLLISION_MAGNIFIER //Arbitrary amplifier to collisions (used to be x5, for now x4 because of new math)
+			//Impact forces applied to each ship.
+			var/own_impact_power = CLAMP(other.mass / mass, 0.2, 10) * (total_force * 0.5) //I'm kind of scared of how the masses of big chonkers are going to interact so I'm capping this for now :)
+			var/other_impact_power = CLAMP(mass / other.mass, 0.2, 10) * (total_force * 0.5)
+			if(self_ramvec > other_ramvec)
+				own_impact_power *= 2 //The one having more impact force towards the ramming vector takes more damage.
+			else
+				other_impact_power *= 2
+			var/list/impact_powers = list(own_impact_power, other_impact_power) //List for inplace adjustments
+			var/modulated_col_angle = (col_angle + 360) % 360
+			spec_collision_handling(other, impact_powers, modulated_col_angle)
+			impact_powers = reverseList(impact_powers)
+			other.spec_collision_handling(src, impact_powers, ((modulated_col_angle + 180) % 360))
+			own_impact_power = impact_powers[2] //Remember, we turned this around!
+			other_impact_power = impact_powers[1]
+			if(own_impact_power > 0)
+				take_quadrant_hit(own_impact_power, quadrant_impact(other))
+			if(other_impact_power > 0)
+				other.take_quadrant_hit(other_impact_power, other.quadrant_impact(src))
+
+			next_collision = world.time + OVERMAP_COLLISION_COOLDOWN
+			log_game("[key_name(pilot)] has impacted an overmap ship into [other] \[Total collision force:[total_force]\]")
+			//Uncomment for debug :)
+			//message_admins("COLLISION DEBUG: own mag / ramvec: \[[src_vel_mag]|[self_ramvec]\]; other mag / remvec: \[[other_vel_mag]|[other_ramvec]\]; total force / own force / other force: \[[total_force]|[own_impact_power]|[other_impact_power]\]; Angles - collision angle / vector angle / angle diff / other vector angle / other angle diff: \[CA[col_angle]|VA[velocity.angle()]|AD[self_vector_angle_diff]|OVA[other.velocity.angle()]|OAD[other_vector_angle_diff]\]")
+
+		src.velocity._set(new_src_vel_x, new_src_vel_y)
+		other.velocity._set(new_other_vel_x, new_other_vel_y)
 		return TRUE
 
 	//Update the colliders before we do any kind of calc.

nsv13/code/modules/overmap/types/nanotrasen.dm

@@ -202,6 +202,14 @@
 	overmap_deletion_traits = DAMAGE_STARTS_COUNTDOWN
 	broadside = TRUE
 
+/obj/structure/overmap/nanotrasen/heavy_cruiser/starter/spec_collision_handling(obj/structure/overmap/other_ship, list/impact_powers, impact_angle)
+	var/modified_angle = 360 - ((angle + 630) % 360)
+	var/angle_diff = impact_angle - modified_angle
+	if(abs(angle_diff) > HAMMERHEAD_COLLISION_GUARD_ANGLE)
+		return
+	impact_powers[1] *= 0.5 // x 0.5 self damage
+	impact_powers[2] *= 2.5 // x 2.5 other damage
+
 /obj/structure/overmap/nanotrasen/heavy_cruiser/starter/apply_weapons()
 	weapon_types[FIRE_MODE_AMS] = new /datum/ship_weapon/vls(src)
 	weapon_types[FIRE_MODE_GAUSS] = new /datum/ship_weapon/gauss(src)

nsv13/code/modules/overmap/types/syndicate.dm

@@ -180,6 +180,14 @@
 	combat_dice_type = /datum/combat_dice/destroyer
 	possible_interior_maps = list(/datum/map_template/boarding/destroyer)
 
+/obj/structure/overmap/syndicate/ai/destroyer/spec_collision_handling(obj/structure/overmap/other_ship, list/impact_powers, impact_angle)
+	var/modified_angle = 360 - ((angle + 630) % 360)
+	var/angle_diff = impact_angle - modified_angle
+	if(abs(angle_diff) > HAMMERHEAD_COLLISION_GUARD_ANGLE)
+		return
+	impact_powers[1] *= 0.5 // x 0.5 self damage
+	impact_powers[2] *= 2.5 // x 2.5 other damage
+
 /obj/structure/overmap/syndicate/ai/destroyer/elite
 	name = "Special Ops Torpedo Destroyer"
 	icon_state = "hammerhead_elite"