Make lasers hitscan

sound/items/weapons/attributions.txt

@@ -2,3 +2,5 @@
 	rust_sower_armbomb.ogg - EnterTheJake
 	rust_sower_explode.ogg - EnterTheJake
 }
+
+laser.ogg and laser2.ogg are e-fire.ogg and heavy_laser.ogg from Shiptest (https://github.com/shiptest-ss13/Shiptest), CC BY-SA 3.0.

tgstation.dme

@@ -6925,6 +6925,7 @@
 #include "voidcrew\edits\modules\power\supermatter_anomalies.dm"
 #include "voidcrew\edits\modules\power\turbine\turbine.dm"
 #include "voidcrew\edits\modules\projectiles\boxes_magazines\_box_magazine.dm"
+#include "voidcrew\edits\modules\projectiles\projectile\beams.dm"
 #include "voidcrew\edits\modules\research\designs.dm"
 #include "voidcrew\edits\modules\research\designs\comp_board_designs.dm"
 #include "voidcrew\edits\modules\research\designs\machine_designs.dm"

voidcrew/edits/modules/projectiles/projectile/beams.dm

@@ -0,0 +1,55 @@
+// Voidcrew: the standard laser family is hitscan. A laser lands the moment it is fired and leaves
+// tg's beam tracer along its path, instead of flying as a bolt. Same damage as upstream; the instant
+// hit is the change. Reflection, blocking, glass and every on-hit signal run exactly as for a bolt,
+// because tg's hitscan walks the same per-tile movement and hit code (projectile.dm process_hitscan).
+//
+// Stays a travelling bolt: disablers and other stun beams, X-ray, pulse, emitters, the ship defense
+// turret, lasertag, CTF, mech lasers (below) and the two lasers whose look is the projectile itself.
+
+/obj/projectile/beam/laser
+	hitscan = TRUE
+
+/// Its ball grows as it flies (reduce_range), which a hitscan beam never shows.
+/obj/projectile/beam/laser/accelerator
+	hitscan = FALSE
+
+/// Genetics laser eyes keep their own eye-beam sprite.
+/obj/projectile/beam/laser/laser_eyes
+	hitscan = FALSE
+
+// Lasers outside /beam/laser that laser guns and turrets fire. Upstream gives them no tracer.
+
+/// Laser scattershot and scatter laser shells.
+/obj/projectile/beam/scatter
+	hitscan = TRUE
+	tracer_type = /obj/effect/projectile/tracer/laser
+	muzzle_type = /obj/effect/projectile/muzzle/laser
+	impact_type = /obj/effect/projectile/impact/laser
+
+/// Laser gatling and some turrets.
+/obj/projectile/beam/weak
+	hitscan = TRUE
+	tracer_type = /obj/effect/projectile/tracer/laser
+	muzzle_type = /obj/effect/projectile/muzzle/laser
+	impact_type = /obj/effect/projectile/impact/laser
+
+/// Practice laser guns.
+/obj/projectile/beam/practice
+	hitscan = TRUE
+	tracer_type = /obj/effect/projectile/tracer/laser
+	muzzle_type = /obj/effect/projectile/muzzle/laser
+	impact_type = /obj/effect/projectile/impact/laser
+
+// Mech lasers stay bolts: exosuit weapons are balanced on their own, apart from hand guns.
+
+/obj/projectile/beam/laser/mech
+	hitscan = FALSE
+
+/obj/projectile/beam/laser/heavylaser/mech
+	hitscan = FALSE
+
+/obj/item/mecha_parts/mecha_equipment/weapon/energy/laser
+	projectile = /obj/projectile/beam/laser/mech
+
+/obj/item/mecha_parts/mecha_equipment/weapon/energy/laser/heavy
+	projectile = /obj/projectile/beam/laser/heavylaser/mech

voidcrew/modules/unit_tests/_unit_tests.dm

@@ -93,6 +93,7 @@
 #include "voidcrew_gene_injector_loot.dm"
 #include "voidcrew_helm_access.dm"
 #include "voidcrew_helpers.dm"
+#include "voidcrew_hitscan_lasers.dm"
 #include "voidcrew_hull_containment.dm"
 #include "voidcrew_hull_survey.dm"
 #include "voidcrew_launch_access.dm"

voidcrew/modules/unit_tests/voidcrew_hitscan_lasers.dm

@@ -0,0 +1,57 @@
+/// Standard lasers are hitscan with a visible tracer; the beams we chose to keep as bolts are not.
+/datum/unit_test/voidcrew_hitscan_lasers/Run()
+	var/list/obj/projectile/hitscan_types = list(
+		/obj/projectile/beam/laser,
+		/obj/projectile/beam/laser/carbine,
+		/obj/projectile/beam/laser/carbine/cybersun,
+		/obj/projectile/beam/laser/hellfire,
+		/obj/projectile/beam/laser/heavylaser,
+		/obj/projectile/beam/laser/musket,
+		/obj/projectile/beam/laser/outpost,
+		/obj/projectile/beam/scatter,
+		/obj/projectile/beam/weak/penetrator,
+		/obj/projectile/beam/practice,
+	)
+	for(var/obj/projectile/laser_type as anything in hitscan_types)
+		TEST_ASSERT(initial(laser_type.hitscan), "[laser_type] is not hitscan")
+		TEST_ASSERT_NOTNULL(initial(laser_type.tracer_type), "[laser_type] is hitscan with no tracer, so its beam is invisible")
+
+	var/list/obj/projectile/bolt_types = list(
+		/obj/projectile/beam/disabler,
+		/obj/projectile/beam/xray,
+		/obj/projectile/beam/pulse,
+		/obj/projectile/beam/emitter,
+		/obj/projectile/beam/ship_defense,
+		/obj/projectile/beam/laser/accelerator,
+		/obj/projectile/beam/laser/laser_eyes,
+		/obj/projectile/beam/laser/mech,
+		/obj/projectile/beam/laser/heavylaser/mech,
+	)
+	for(var/obj/projectile/bolt_type as anything in bolt_types)
+		TEST_ASSERT(!initial(bolt_type.hitscan), "[bolt_type] became hitscan")
+
+	var/obj/item/mecha_parts/mecha_equipment/weapon/energy/laser/mech_laser = /obj/item/mecha_parts/mecha_equipment/weapon/energy/laser
+	TEST_ASSERT_EQUAL(initial(mech_laser.projectile), /obj/projectile/beam/laser/mech, "The mech laser fires a hitscan laser")
+
+/// A hitscan laser fired at someone three tiles away lands, from a bare projectile and from a trigger pull.
+/// The beam finishes on the firing tick unless the tick is overrun, which it always is in a test, so wait for it.
+/datum/unit_test/voidcrew_hitscan_laser_lands/Run()
+	var/mob/living/carbon/human/consistent/shooter = allocate(/mob/living/carbon/human/consistent, run_loc_floor_bottom_left)
+	var/turf/target_turf = locate(run_loc_floor_bottom_left.x + 3, run_loc_floor_bottom_left.y, run_loc_floor_bottom_left.z)
+	var/mob/living/carbon/human/consistent/target = allocate(/mob/living/carbon/human/consistent, target_turf)
+
+	var/obj/projectile/beam/laser/beam = new(run_loc_floor_bottom_left)
+	beam.aim_projectile(target, shooter)
+	beam.firer = shooter
+	beam.fire()
+	UNTIL(QDELETED(beam))
+	TEST_ASSERT(target.getFireLoss() > 0, "A hitscan laser fired at a target three tiles away missed")
+
+	var/before = target.getFireLoss()
+	var/obj/item/gun/energy/laser/rifle = allocate(/obj/item/gun/energy/laser)
+	TEST_ASSERT(shooter.put_in_active_hand(rifle), "The shooter could not hold the laser rifle")
+	var/charge_before = rifle.cell.charge
+	rifle.fire_gun(target, shooter, FALSE)
+	TEST_ASSERT(rifle.cell.charge < charge_before, "The laser rifle did not fire")
+	sleep(1 SECONDS)
+	TEST_ASSERT(target.getFireLoss() > before, "A laser rifle shot three tiles away missed")