Early Assets, Lateloaded Assets, and Debugging Tools (#4696)

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## About The Pull Request
Various asset systems I want in before more TGUI work. and also
byond-tracy support... and also light update debugging...
## Changelog
🆑
tweak: Chem Master UI has been reworked slightly.

code/modules/asset_cache/asset_list.dm

@@ -6,8 +6,16 @@
 //all of our asset datums, used for referring to these later
 GLOBAL_LIST_EMPTY(asset_datums)
 
-//get an assetdatum or make a new one
+/// Get an assetdatum or make a new one.
 /proc/get_asset_datum(type)
+	var/datum/asset/loaded_asset = GLOB.asset_datums[type] || new type()
+	return loaded_asset.ensure_ready()
+
+/**
+ * Get an assetdatum or make a new one.
+ *! But does NOT ensure it's filled, if you want that use get_asset_datum()
+ */
+/proc/load_asset_datum(type)
 	return GLOB.asset_datums[type] || new type()
 
 /datum/asset
@@ -18,11 +26,25 @@ GLOBAL_LIST_EMPTY(asset_datums)
 	/// Whether or not this asset should be loaded in the "early assets" SS
 	var/early = FALSE
 
-	/// Whether or not this asset can be cached across rounds of the same commit under the `CACHE_ASSETS` config.
-	/// This is not a *guarantee* the asset will be cached. Not all asset subtypes respect this field, and the
-	/// config can, of course, be disabled.
+	/**
+	 * Whether or not this asset can be cached across rounds of the same commit under the `CACHE_ASSETS` config.
+	 * This is not a *guarantee* the asset will be cached. Not all asset subtypes respect this field, and the
+	 * config can, of course, be disabled.
+	 */
 	var/cross_round_cachable = FALSE
 
+/**
+ * Stub that allows us to react to something trying to get us.
+ * Not useful here, more handy for sprite sheets.
+ */
+/datum/asset/proc/ensure_ready()
+	return src
+
+/// Stub to hook into if your asset is having its generation queued by SSasset_loading
+/datum/asset/proc/queued_generation()
+	CRASH("[type] inserted into SSasset_loading despite not implementing /proc/queued_generation")
+
+
 /datum/asset/New()
 	GLOB.asset_datums[type] = src
 	register()
@@ -51,12 +73,16 @@ GLOBAL_LIST_EMPTY(asset_datums)
 /// If you don't need anything complicated.
 /datum/asset/simple
 	_abstract = /datum/asset/simple
-	/// list of assets for this datum in the form of:
-	/// asset_filename = asset_file. At runtime the asset_file will be
-	/// converted into a asset_cache datum.
+	/**
+	 * List of assets for this datum in the form of:
+	 * * asset_filename = asset_file.
+	 * At runtime the asset_file will be converted into a asset_cache datum.
+	 */
 	var/assets = list()
-	/// Set to true to have this asset also be sent via the legacy browse_rsc
-	/// system when cdn transports are enabled?
+	/**
+	 * Set to true to have this asset also be sent via the legacy browse_rsc
+	 * system when cdn transports are enabled?
+	 */
 	var/legacy = FALSE
 	/// TRUE for keeping local asset names when browse_rsc backend is used
 	var/keep_local_name = FALSE
@@ -88,7 +114,7 @@ GLOBAL_LIST_EMPTY(asset_datums)
 
 /datum/asset/group/register()
 	for(var/type in children)
-		get_asset_datum(type)
+		load_asset_datum(type)
 
 /datum/asset/group/send(client/C)
 	for(var/type in children)
@@ -101,28 +127,44 @@ GLOBAL_LIST_EMPTY(asset_datums)
 		var/datum/asset/A = get_asset_datum(type)
 		. += A.get_url_mappings()
 
-// spritesheet implementation - coalesces various icons into a single .png file
-// and uses CSS to select icons out of that file - saves on transferring some
-// 1400-odd individual PNG files
+/**
+ * spritesheet implementation - coalesces various icons into a single .png file
+ * and uses CSS to select icons out of that file - saves on transferring some
+ * 1400-odd individual PNG files
+ */
 #define SPR_SIZE 1
-#define SPR_IDX 2
-#define SPRSZ_COUNT 1
-#define SPRSZ_ICON 2
+#define SPR_IDX  2
+
+#define SPRSZ_COUNT    1
+#define SPRSZ_ICON     2
 #define SPRSZ_STRIPPED 3
 
 /datum/asset/spritesheet
 	_abstract = /datum/asset/spritesheet
 	var/name
-	var/list/sizes = list()    // "32x32" -> list(10, icon/normal, icon/stripped)
-	var/list/sprites = list()  // "foo_bar" -> list("32x32", 5)
+	/**
+	 * List of arguments to pass into queuedInsert.
+	 * Exists so we can queue icon insertion, mostly for stuff like preferences.
+	 */
+	var/list/to_generate = list()
+	/// "32x32" -> list(10, icon/normal, icon/stripped)
+	var/list/sizes = list()
+	/// "foo_bar" -> list("32x32", 5)
+	var/list/sprites = list()
 	var/list/cached_spritesheets_needed
 	var/generating_cache = FALSE
+	var/fully_generated = FALSE
+	/**
+	 * If this asset should be fully loaded on new
+	 * Defaults to false so we can process this stuff nicely
+	 */
+	var/load_immediately = FALSE
 
 /datum/asset/spritesheet/should_refresh()
 	if (..())
 		return TRUE
 
-	// Static so that the result is the same, even when the files are created, for this run
+	/// Static so that the result is the same, even when the files are created, for this run.
 	var/static/should_refresh = null
 
 	if (isnull(should_refresh))
@@ -140,7 +182,25 @@ GLOBAL_LIST_EMPTY(asset_datums)
 	if (!should_refresh() && read_from_cache())
 		return
 
+	/// If it's cached, may as well load it now, while the loading is cheap
+	if(CONFIG_GET(flag/cache_assets) && cross_round_cachable)
+		load_immediately = TRUE
+
 	create_spritesheets()
+	if(load_immediately)
+		realize_spritesheets(yield = FALSE)
+	else
+		SSasset_loading.generate_queue += src
+
+/datum/asset/spritesheet/proc/realize_spritesheets(yield)
+	if(fully_generated)
+		return
+	while(length(to_generate))
+		var/list/stored_args = to_generate[to_generate.len]
+		to_generate.len--
+		queuedInsert(arglist(stored_args))
+		if(yield && TICK_CHECK)
+			return
 
 	ensure_stripped()
 	for(var/size_id in sizes)
@@ -156,6 +216,18 @@ GLOBAL_LIST_EMPTY(asset_datums)
 	if (CONFIG_GET(flag/cache_assets) && cross_round_cachable)
 		write_to_cache()
 
+	fully_generated = TRUE
+	// If we were ever in there, remove ourselves
+	SSasset_loading.generate_queue -= src
+
+/datum/asset/spritesheet/queued_generation()
+	realize_spritesheets(yield = TRUE)
+
+/datum/asset/spritesheet/ensure_ready()
+	if(!fully_generated)
+		realize_spritesheets(yield = FALSE)
+	return ..()
+
 /datum/asset/spritesheet/send(client/client)
 	if (!name)
 		return
@@ -270,17 +342,31 @@ GLOBAL_LIST_EMPTY(asset_datums)
 
 	return mappings
 
-/// Override this in order to start the creation of the spritehseet.
-/// This is where all your Insert, InsertAll, etc calls should be inside.
+/**
+ *! Override this in order to start the creation of the spritehseet.
+ *! This is where all your Insert, InsertAll, etc calls should be inside.
+ */
 /datum/asset/spritesheet/proc/create_spritesheets()
 	SHOULD_CALL_PARENT(FALSE)
 	CRASH("create_spritesheets() not implemented for [type]!")
 
 /datum/asset/spritesheet/proc/Insert(sprite_name, icon/I, icon_state="", dir=SOUTH, frame=1, moving=FALSE)
+	if(load_immediately)
+		queuedInsert(sprite_name, I, icon_state, dir, frame, moving)
+	else
+		to_generate += list(args.Copy())
+
+/**
+ * LEMON NOTE
+ * A GOON CODER SAYS BAD ICON ERRORS CAN BE THROWN BY THE "ICON CACHE"
+ * APPARENTLY IT MAKES ICONS IMMUTABLE
+ * LOOK INTO USING THE MUTABLE APPEARANCE PATTERN HERE
+ */
+/datum/asset/spritesheet/proc/queuedInsert(sprite_name, icon/I, icon_state="", dir=SOUTH, frame=1, moving=FALSE)
 	I = icon(I, icon_state=icon_state, dir=dir, frame=frame, moving=moving)
-	if (!I || !length(icon_states(I)))  // that direction or state doesn't exist
+	if (!I || !length(icon_states(I))) // That direction or state doesn't exist!
 		return
-	//any sprite modifications we want to do (aka, coloring a greyscaled asset)
+	// Any sprite modifications we want to do (aka, coloring a greyscaled asset)
 	I = ModifyInserted(I)
 	var/size_id = "[I.Width()]x[I.Height()]"
 	var/size = sizes[size_id]
@@ -291,8 +377,10 @@ GLOBAL_LIST_EMPTY(asset_datums)
 	if (size)
 		var/position = size[SPRSZ_COUNT]++
 		var/icon/sheet = size[SPRSZ_ICON]
+		var/icon/sheet_copy = icon(sheet)
 		size[SPRSZ_STRIPPED] = null
-		sheet.Insert(I, icon_state=sprite_name)
+		sheet_copy.Insert(I, icon_state=sprite_name)
+		size[SPRSZ_ICON] = sheet_copy
 		sprites[sprite_name] = list(size_id, position)
 	else
 		sizes[size_id] = size = list(1, I, null)

code/modules/asset_cache/assets/chemistry/bottles.dm

@@ -0,0 +1,8 @@
+/datum/asset/spritesheet/simple/bottles
+	name = "bottles"
+	assets = list(
+		"bottle1" = 'icons/runtime/assets/medical/bottles/bottle1.png',
+		"bottle2" = 'icons/runtime/assets/medical/bottles/bottle2.png',
+		"bottle3" = 'icons/runtime/assets/medical/bottles/bottle3.png',
+		"bottle4" = 'icons/runtime/assets/medical/bottles/bottle4.png',
+	)

code/modules/asset_cache/assets/chemistry/patches.dm

@@ -0,0 +1,8 @@
+/datum/asset/spritesheet/simple/patches
+	name = "patches"
+	assets = list(
+		"patch"       = 'icons/runtime/assets/medical/patches/patch.png',
+		"patch_brute" = 'icons/runtime/assets/medical/patches/patch_brute.png',
+		"patch_burn"  = 'icons/runtime/assets/medical/patches/patch_burn.png',
+		"patch_both"  = 'icons/runtime/assets/medical/patches/patch_both.png',
+	)

code/modules/asset_cache/assets/chemistry/pills.dm

@@ -0,0 +1,26 @@
+/datum/asset/spritesheet/simple/pills
+	name = "pills"
+	assets = list(
+		"pill1"  = 'icons/runtime/assets/medical/pills/pill1.png',
+		"pill2"  = 'icons/runtime/assets/medical/pills/pill2.png',
+		"pill3"  = 'icons/runtime/assets/medical/pills/pill3.png',
+		"pill4"  = 'icons/runtime/assets/medical/pills/pill4.png',
+		"pill5"  = 'icons/runtime/assets/medical/pills/pill5.png',
+		"pill6"  = 'icons/runtime/assets/medical/pills/pill6.png',
+		"pill7"  = 'icons/runtime/assets/medical/pills/pill7.png',
+		"pill8"  = 'icons/runtime/assets/medical/pills/pill8.png',
+		"pill9"  = 'icons/runtime/assets/medical/pills/pill9.png',
+		"pill10" = 'icons/runtime/assets/medical/pills/pill10.png',
+		"pill11" = 'icons/runtime/assets/medical/pills/pill11.png',
+		"pill12" = 'icons/runtime/assets/medical/pills/pill12.png',
+		"pill13" = 'icons/runtime/assets/medical/pills/pill13.png',
+		"pill14" = 'icons/runtime/assets/medical/pills/pill14.png',
+		"pill15" = 'icons/runtime/assets/medical/pills/pill15.png',
+		"pill16" = 'icons/runtime/assets/medical/pills/pill16.png',
+		"pill17" = 'icons/runtime/assets/medical/pills/pill17.png',
+		"pill18" = 'icons/runtime/assets/medical/pills/pill18.png',
+		"pill19" = 'icons/runtime/assets/medical/pills/pill19.png',
+		"pill20" = 'icons/runtime/assets/medical/pills/pill20.png',
+		"pill21" = 'icons/runtime/assets/medical/pills/pill21.png',
+		"pill22" = 'icons/runtime/assets/medical/pills/pill22.png',
+	)

code/modules/asset_cache/assets/condiments.dm

@@ -1,20 +1,20 @@
 /datum/asset/spritesheet/simple/condiments
 	name = "condiments"
 	assets = list(
-		CONDIMASTER_STYLE_FALLBACK = 'icons/ui_icons/condiments/emptycondiment.png',
-		"enzyme" = 'icons/ui_icons/condiments/enzyme.png',
-		"flour" = 'icons/ui_icons/condiments/flour.png',
-		"mayonnaise" = 'icons/ui_icons/condiments/mayonnaise.png',
-		"milk" = 'icons/ui_icons/condiments/milk.png',
-		"blackpepper" = 'icons/ui_icons/condiments/peppermillsmall.png',
-		"rice" = 'icons/ui_icons/condiments/rice.png',
-		"sodiumchloride" = 'icons/ui_icons/condiments/saltshakersmall.png',
-		"soymilk" = 'icons/ui_icons/condiments/soymilk.png',
-		"soysauce" = 'icons/ui_icons/condiments/soysauce.png',
-		"sugar" = 'icons/ui_icons/condiments/sugar.png',
-		"ketchup" = 'icons/ui_icons/condiments/ketchup.png',
-		"capsaicin" = 'icons/ui_icons/condiments/hotsauce.png',
-		"frostoil" = 'icons/ui_icons/condiments/coldsauce.png',
-		"bbqsauce" = 'icons/ui_icons/condiments/bbqsauce.png',
-		"cornoil" = 'icons/ui_icons/condiments/oliveoil.png',
+		CONDIMASTER_STYLE_FALLBACK = 'icons/runtime/assets/condiments/emptycondiment.png',
+		"enzyme"                   = 'icons/runtime/assets/condiments/enzyme.png',
+		"flour"                    = 'icons/runtime/assets/condiments/flour.png',
+		"mayonnaise"               = 'icons/runtime/assets/condiments/mayonnaise.png',
+		"milk"                     = 'icons/runtime/assets/condiments/milk.png',
+		"blackpepper"              = 'icons/runtime/assets/condiments/peppermillsmall.png',
+		"rice"                     = 'icons/runtime/assets/condiments/rice.png',
+		"sodiumchloride"           = 'icons/runtime/assets/condiments/saltshakersmall.png',
+		"soymilk"                  = 'icons/runtime/assets/condiments/soymilk.png',
+		"soysauce"                 = 'icons/runtime/assets/condiments/soysauce.png',
+		"sugar"                    = 'icons/runtime/assets/condiments/sugar.png',
+		"ketchup"                  = 'icons/runtime/assets/condiments/ketchup.png',
+		"capsaicin"                = 'icons/runtime/assets/condiments/hotsauce.png',
+		"frostoil"                 = 'icons/runtime/assets/condiments/coldsauce.png',
+		"bbqsauce"                 = 'icons/runtime/assets/condiments/bbqsauce.png',
+		"cornoil"                  = 'icons/runtime/assets/condiments/oliveoil.png',
 	)

code/modules/asset_cache/assets/patches.dm

@@ -1,8 +0,0 @@
-/datum/asset/spritesheet/simple/patches
-	name = "patches"
-	assets = list(
-		"bandaid" = 'icons/ui_icons/patches/bandaid.png',
-		"bandaid_brute" = 'icons/ui_icons/patches/bandaid_brute.png',
-		"bandaid_burn" = 'icons/ui_icons/patches/bandaid_burn.png',
-		"bandaid_both" = 'icons/ui_icons/patches/bandaid_both.png'
-	)

code/modules/asset_cache/assets/pills.dm

@@ -1,40 +0,0 @@
-/datum/asset/simple/namespaced/chem_master
-	keep_local_name = TRUE
-
-/datum/asset/simple/namespaced/chem_master/register()
-	for(var/i = 1 to 24)
-		assets["pill[i].png"] = icon('icons/obj/chemical.dmi', "pill[i]")
-
-	for(var/i = 1 to 4)
-		assets["bottle-[i].png"] = icon('icons/obj/chemical.dmi', "bottle-[i]")
-
-	return ..()
-
-/*
-/datum/asset/spritesheet/simple/pills
-	name = "pills"
-	assets = list(
-		"pill1" = 'icons/ui_icons/pills/pill1.png',
-		"pill2" = 'icons/ui_icons/pills/pill2.png',
-		"pill3" = 'icons/ui_icons/pills/pill3.png',
-		"pill4" = 'icons/ui_icons/pills/pill4.png',
-		"pill5" = 'icons/ui_icons/pills/pill5.png',
-		"pill6" = 'icons/ui_icons/pills/pill6.png',
-		"pill7" = 'icons/ui_icons/pills/pill7.png',
-		"pill8" = 'icons/ui_icons/pills/pill8.png',
-		"pill9" = 'icons/ui_icons/pills/pill9.png',
-		"pill10" = 'icons/ui_icons/pills/pill10.png',
-		"pill11" = 'icons/ui_icons/pills/pill11.png',
-		"pill12" = 'icons/ui_icons/pills/pill12.png',
-		"pill13" = 'icons/ui_icons/pills/pill13.png',
-		"pill14" = 'icons/ui_icons/pills/pill14.png',
-		"pill15" = 'icons/ui_icons/pills/pill15.png',
-		"pill16" = 'icons/ui_icons/pills/pill16.png',
-		"pill17" = 'icons/ui_icons/pills/pill17.png',
-		"pill18" = 'icons/ui_icons/pills/pill18.png',
-		"pill19" = 'icons/ui_icons/pills/pill19.png',
-		"pill20" = 'icons/ui_icons/pills/pill20.png',
-		"pill21" = 'icons/ui_icons/pills/pill21.png',
-		"pill22" = 'icons/ui_icons/pills/pill22.png',
-	)
-*/