experimental caching performance tweaks (#3364)

Changes the asset cache's on-connect cache to use a ticking subsystem instead of sleeps and timers to slowly send assets to clients.

code/modules/client/asset_cache.dm

@@ -25,7 +25,7 @@ You can set verify to TRUE if you want send() to sleep until the client has the
 
 //This proc sends the asset to the client, but only if it needs it.
 //This proc blocks(sleeps) unless verify is set to false
-/proc/send_asset(var/client/client, var/asset_name, var/verify = TRUE)
+/proc/send_asset(client/client, asset_name, verify = TRUE)
 	if(!istype(client))
 		if(ismob(client))
 			var/mob/M = client
@@ -72,7 +72,7 @@ You can set verify to TRUE if you want send() to sleep until the client has the
 	return 1
 
 //This proc blocks(sleeps) unless verify is set to false
-/proc/send_asset_list(var/client/client, var/list/asset_list, var/verify = TRUE)
+/proc/send_asset_list(client/client, list/asset_list, verify = TRUE)
 	if(!istype(client))
 		if(ismob(client))
 			var/mob/M = client
@@ -122,20 +122,9 @@ You can set verify to TRUE if you want send() to sleep until the client has the
 
 	return 1
 
-//This proc will download the files without clogging up the browse() queue, used for passively sending files on connection start.
-//The proc calls procs that sleep for long times.
-/proc/getFilesSlow(var/client/client, var/list/files, var/register_asset = TRUE)
-	for(var/file in files)
-		if (!client)
-			break
-		if (register_asset)
-			register_asset(file,files[file])
-		send_asset(client,file)
-		sleep(0) //queuing calls like this too quickly can cause issues in some client versions
-
 //This proc "registers" an asset, it adds it to the cache for further use, you cannot touch it from this point on or you'll fuck things up.
 //if it's an icon or something be careful, you'll have to copy it before further use.
-/proc/register_asset(var/asset_name, var/asset)
+/proc/register_asset(asset_name, asset)
 	SSassets.cache[asset_name] = asset
 
 //These datums are used to populate the asset cache, the proc "register()" does this.

code/modules/client/client procs.dm

@@ -380,6 +380,7 @@
 		admins -= src
 	directory -= ckey
 	clients -= src
+	SSassets.handle_disconnect(src)
 	return ..()
 
 
@@ -491,9 +492,7 @@
 
 //send resources to the client. It's here in its own proc so we can move it around easiliy if need be
 /client/proc/send_resources()
-	spawn (10) //removing this spawn causes all clients to not get verbs.
-		//Precache the client with all other assets slowly, so as to not block other browse() calls
-		getFilesSlow(src, SSassets.cache, register_asset = FALSE)
+	SSassets.handle_connect(src)
 
 /mob/proc/MayRespawn()
 	return 0