[MIRROR] Adds support for cold mist effect for low temperatures (#1472)

Co-authored-by: CrimsonShrike <[email protected]>

code/__defines/__renderer.dm

@@ -40,6 +40,8 @@
 
 #define HEAT_EFFECT_PLANE -4
 #define HEAT_EFFECT_TARGET    "*heat"
+#define COLD_EFFECT_TARGET    "*cold"
+#define COLD_EFFECT_BACK_TARGET "*coldb"
 #define HEAT_COMPOSITE_TARGET "*heatc"
 #define WARP_EFFECT_PLANE -3
 

code/__defines/_renderer.dm

@@ -237,7 +237,6 @@ GLOBAL_LIST_EMPTY(zmimic_renderers)
 	group = RENDER_GROUP_FINAL
 	plane = RENDER_GROUP_SCENE
 
-
 /// Render group for stuff OUTSIDE the typical game context - UI, full screen effects, etc.
 /atom/movable/renderer/screen_group
 	name = "Screen Group"
@@ -279,6 +278,7 @@ GLOBAL_LIST_EMPTY(zmimic_renderers)
 	mouse_opacity = MOUSE_OPACITY_UNCLICKABLE
 
 	var/obj/gas_heat_object = null
+	var/obj/gas_cold_object = null // Not strictly a heat effect but similar setup so may as well
 
 /atom/movable/renderer/heat/proc/Setup()
 	var/mob/M = owner
@@ -289,17 +289,27 @@ GLOBAL_LIST_EMPTY(zmimic_renderers)
 		if(gas_heat_object)
 			vis_contents -= gas_heat_object
 
+		if(gas_cold_object)
+			vis_contents -= gas_cold_object
+
 		if (quality == GLOB.PREF_LOW)
 			QDEL_NULL(gas_heat_object)
 			gas_heat_object = new /obj/heat(null)
+
+			QDEL_NULL(gas_cold_object)
+			gas_cold_object = new /obj/effect/cold_mist_gas(null)
 		else
 			QDEL_NULL(gas_heat_object)
+			QDEL_NULL(gas_cold_object)
+			gas_cold_object = new /obj/particle_emitter/mist/gas(null)
 			if (quality == GLOB.PREF_MED)
 				gas_heat_object = new /obj/particle_emitter/heat(null)
 			else if (quality == GLOB.PREF_HIGH)
 				gas_heat_object = new /obj/particle_emitter/heat/high(null)
 
 		vis_contents += gas_heat_object
+		if(config.enable_cold_mist)
+			vis_contents += gas_cold_object
 
 
 /atom/movable/renderer/heat/Initialize()

code/__defines/atmos.dm

@@ -49,6 +49,9 @@
 #define CARBON_LIFEFORM_FIRE_RESISTANCE (T0C + 200)
 #define CARBON_LIFEFORM_FIRE_DAMAGE     4
 
+#define FOGGING_TEMPERATURE (T0C + 5)
+#define MAX_FOG_TEMPERATURE (T0C - 50)
+
 // Phoron fire properties.
 #define PHORON_MINIMUM_BURN_TEMPERATURE    (T0C +  126) //400 K - autoignite temperature in tanks and canisters - enclosed environments I guess
 #define PHORON_FLASHPOINT                  (T0C +  246) //519 K - autoignite temperature in air if that ever gets implemented.
@@ -126,3 +129,4 @@
 #define GAS_PHORON				"phoron"
 #define GAS_BORON				"boron"
 #define GAS_HEAT                "heat" //Not a real gas, used for visual effects
+#define GAS_COLD                "cold" //Not a real gas, used for visual effects

code/controllers/configuration.dm

@@ -434,6 +434,8 @@
 	var/static/shutdown_on_reboot = FALSE
 	// [/SIERRA-ADD]
 
+	var/static/enable_cold_mist = FALSE
+
 
 /datum/configuration/New()
 	load_config()
@@ -861,6 +863,8 @@
 			if("minimum_byondacc_age")
 				minimum_byondacc_age = text2num(value)
 			// [/SIERRA-ADD]
+			if ("enable_cold_mist")
+				enable_cold_mist = TRUE
 			else
 				log_misc("Unknown setting in config/config.txt: '[name]'")
 

code/game/objects/effects/misc.dm

@@ -139,3 +139,33 @@
 	pixel_x = -176
 	pixel_y = -176
 	z_flags = ZMM_IGNORE
+
+/obj/effect/cold_mist
+	icon = 'icons/effects/tile_effects.dmi'
+	icon_state = "frontfog"
+	layer = FIRE_LAYER
+	alpha = 170
+
+/obj/effect/cold_mist/Initialize()
+	. = ..()
+	AddOverlays(image(icon = 'icons/effects/tile_effects.dmi', icon_state = "backfog", layer = BELOW_OBJ_LAYER))
+
+//Handling it as an overlay is not layering properly with render targets
+/obj/effect/cold_mist_gas_back
+	icon = 'icons/effects/tile_effects.dmi'
+	icon_state = "backfog"
+	layer = BELOW_OBJ_LAYER
+	render_target = COLD_EFFECT_BACK_TARGET
+
+/obj/effect/cold_mist_gas
+	icon = 'icons/effects/tile_effects.dmi'
+	icon_state = "frontfog"
+	render_target = COLD_EFFECT_TARGET
+	layer = FIRE_LAYER
+	appearance_flags = DEFAULT_APPEARANCE_FLAGS | KEEP_TOGETHER
+	var/obj/effect/cold_mist_gas_back/b = null
+
+/obj/effect/cold_mist_gas/Initialize()
+	. = ..()
+	b = new()
+	vis_contents += b

code/game/objects/effects/particles/particles.dm

@@ -86,6 +86,28 @@
 	color = "white"
 
 
+/particles/mist
+	name = "mist"
+	icon = 'icons/effects/particles.dmi'
+	icon_state = list("steam_1" = 1, "steam_2" = 1, "steam_3" = 1)
+	count = 500
+	spawning = 4
+	lifespan = 5 SECONDS
+	fade = 1 SECOND
+	fadein = 1 SECOND
+	velocity = generator("box", list(-0.5, -0.25, 0), list(0.5, 0.25, 0), NORMAL_RAND)
+	position = generator("box", list(-20, -16), list(20, -2), UNIFORM_RAND)
+	friction = 0.2
+	grow = 0.0015
+
+
+/particles/mist/back
+	name = "mist_back"
+	spawning = 7
+	position = generator("box", list(-20, -1), list(20, 20), UNIFORM_RAND)
+	lifespan = 6 SECONDS
+	fadein = 1.5 SECONDS
+
 /particles/fire_sparks
 	name = "fire sparks"
 	width = 500
@@ -333,3 +355,31 @@
 
 /obj/particle_emitter/heat/high
 	particle_type = "high heat"
+
+
+/obj/particle_emitter/mist
+	particle_type = "mist"
+	layer = FIRE_LAYER
+
+/obj/particle_emitter/mist/back
+	particle_type = "mist_back"
+	layer = BELOW_OBJ_LAYER
+
+
+/obj/particle_emitter/mist/back/gas
+	render_target = COLD_EFFECT_BACK_TARGET
+
+/obj/particle_emitter/mist/back/gas/Initialize(mapload, time, _color)
+	. = ..()
+	filters += filter(type="alpha", render_source = COLD_EFFECT_TARGET, flags = MASK_INVERSE)
+
+
+//for cold gas effect
+/obj/particle_emitter/mist/gas
+	render_target = COLD_EFFECT_TARGET
+	var/obj/particle_emitter/mist/back/b = /obj/particle_emitter/mist/back/gas
+
+/obj/particle_emitter/mist/gas/Initialize(mapload, time, _color)
+	. = ..()
+	b = new b(null)
+	vis_contents += b

code/modules/xgm/xgm_gas_data.dm

@@ -117,3 +117,22 @@ var/global/datum/xgm_gas_data/gas_data
 	. = ..()
 	icon = null
 	icon_state = null
+
+/obj/effect/gas_cold_back
+	render_source = COLD_EFFECT_BACK_TARGET
+	plane = DEFAULT_PLANE
+	layer = BELOW_OBJ_LAYER
+
+/obj/gas_overlay/cold
+	name = "gas"
+	desc = "You shouldn't be clicking this."
+	gas_id = GAS_COLD
+	render_source = COLD_EFFECT_TARGET
+	var/obj/effect/gas_cold_back/b = null
+
+/obj/gas_overlay/cold/Initialize(mapload, gas)
+	. = ..()
+	icon = null
+	icon_state = null
+	b = new()
+	vis_contents += b

code/modules/xgm/xgm_gas_mixture.dm

@@ -349,6 +349,8 @@
 	for(var/obj/gas_overlay/O in graphic)
 		if(istype(O, /obj/gas_overlay/heat))
 			continue
+		if(istype(O, /obj/gas_overlay/cold))
+			continue
 		if(gas[O.gas_id] <= gas_data.overlay_limit[O.gas_id])
 			LAZYADD(graphic_remove, O)
 	for(var/g in gas_data.overlay_limit)
@@ -359,13 +361,20 @@
 				LAZYADD(graphic_add, tile_overlay)
 	. = 0
 
-	var/tile_overlay = get_tile_overlay(GAS_HEAT)
+	var/heat_overlay = get_tile_overlay(GAS_HEAT)
 	//If it's hot add something
 	if(temperature >= CARBON_LIFEFORM_FIRE_RESISTANCE)
-		if(!(tile_overlay in graphic))
-			LAZYADD(graphic_add, tile_overlay)
-	else if (tile_overlay in graphic)
-		LAZYADD(graphic_remove, tile_overlay)
+		if(!(heat_overlay in graphic))
+			LAZYADD(graphic_add, heat_overlay)
+	else if (heat_overlay in graphic)
+		LAZYADD(graphic_remove, heat_overlay)
+
+	var/cold_overlay = get_tile_overlay(GAS_COLD)
+	if(temperature <= FOGGING_TEMPERATURE && (return_pressure() >= (ONE_ATMOSPHERE / 4)))
+		if(!(cold_overlay in graphic))
+			LAZYADD(graphic_add, cold_overlay)
+	else if (cold_overlay in graphic)
+		LAZYADD(graphic_remove, cold_overlay)
 
 	//Apply changes
 	if(graphic_add && length(graphic_add))
@@ -382,6 +391,11 @@
 				if(new_alpha != O.alpha)
 					O.update_alpha_animation(new_alpha)
 				continue
+			if(istype(O, /obj/gas_overlay/cold))
+				var/new_alpha = clamp(max(125, 200 * (1 - ((temperature - MAX_FOG_TEMPERATURE) / (FOGGING_TEMPERATURE - MAX_FOG_TEMPERATURE)))), 125, 200)
+				if(new_alpha != O.alpha)
+					O.update_alpha_animation(new_alpha)
+				continue
 			var/concentration_mod = clamp(gas[O.gas_id] / total_moles, 0.1, 1)
 			var/new_alpha = min(230, round(pressure_mod * concentration_mod * 180, 5))
 			if(new_alpha != O.alpha)
@@ -391,6 +405,8 @@
 	if(!LAZYACCESS(tile_overlay_cache, gas_id))
 		if(gas_id == GAS_HEAT) //Not a real gas but functionally same thing
 			LAZYSET(tile_overlay_cache, gas_id, new/obj/gas_overlay/heat(null, GAS_HEAT))
+		if(gas_id == GAS_COLD) //Not a real gas but functionally same thing
+			LAZYSET(tile_overlay_cache, gas_id, new/obj/gas_overlay/cold(null, GAS_COLD))
 		else
 			LAZYSET(tile_overlay_cache, gas_id, new/obj/gas_overlay(null, gas_id))
 	return tile_overlay_cache[gas_id]