spraycan: use permanent decals

instead of using auto decals, letting them time out and just Not
replacing them when they're meant to be gone, this spawns a permanent
decal (not affected by decal limit) and explicitly deletes it when
necessary.
as a consequence of this, spraying more than 11 decals Immediately
removes the oldest spray.

Addresses issue #1

decaldef.txt

@@ -1,20 +1,12 @@
-fader KiriInstantFade
-{
-    DecayStart 60.0
-    DecayTime 0.0
-}
-
 decal KiriTestDecal
 {
 	pic KSPYA0
-	animator KiriInstantFade
     randomflipx
 }
 
 decal SnekSpray_TransPride
 {
 	pic KSPYA0
-	animator KiriInstantFade
     randomflipx
     translucent 0.8
 }
@@ -22,7 +14,6 @@ decal SnekSpray_TransPride
 decal SnekSpray_LesbianPride
 {
 	pic KSPYB0
-	animator KiriInstantFade
     randomflipx
     translucent 0.8
 }
@@ -30,7 +21,6 @@ decal SnekSpray_LesbianPride
 decal SnekSpray_NBPride
 {
 	pic KSPYC0
-	animator KiriInstantFade
     randomflipx
     translucent 0.8
 }
@@ -38,7 +28,6 @@ decal SnekSpray_NBPride
 decal SnekSpray_AcePride
 {
 	pic KSPYD0
-	animator KiriInstantFade
     randomflipx
     translucent 0.8
 }
@@ -46,34 +35,29 @@ decal SnekSpray_AcePride
 decal SnekSpray_ProgressPride
 {
 	pic KSPYE0
-	animator KiriInstantFade
     translucent 0.8
 }
 
 decal SnekSpray_DemiPride
 {
 	pic KSPYF0
-	animator KiriInstantFade
     translucent 0.8
 }
 
 decal SnekSpray_PanPride
 {
 	pic KSPYG0
-	animator KiriInstantFade
     translucent 0.8
 }
 
 decal SnekSpray_SwitchPride
 {
 	pic KSPYH0
-	animator KiriInstantFade
 }
 
 decal SnekSpray_BiPride
 {
 	pic KSPYI0
-	animator KiriInstantFade
     translucent 0.8
     randomflipx
 }
@@ -81,7 +65,6 @@ decal SnekSpray_BiPride
 decal SnekSpray_GayPride
 {
 	pic KSPYJ0
-	animator KiriInstantFade
     translucent 0.8
     randomflipx
 }

zscript/spraycan.zs

@@ -113,8 +113,6 @@ class SnekTechSprayer : HDWeapon
 
             } else {
 
-                Actor spawnedThing;
-                bool success;
                 float zOffset = GunHeight() * 0.8;
                 FLineTraceData lineTraceData;
 
@@ -154,15 +152,12 @@ class SnekTechSprayer : HDWeapon
                         "kiri/spraycan_spray",
                         CHAN_WEAPON);
 
-                    [success, spawnedThing] = A_SpawnItemEx(
+                    let normal = lineTraceData.HitDir;
-                        "SnekTechSprayerDecalSpawner",
+                    let spawnedThing = Actor.Spawn("SnekTechSprayerDecalSpawner", lineTraceData.HitLocation - normal);
-                        xofs : 0, yofs : 0, zofs : zOffset);
-
                     SnekTechSprayerDecalSpawner spawner = SnekTechSprayerDecalSpawner(spawnedThing);
 
-                    if(success && spawner) {
+                    if(spawner) {
-                        spawner.A_SetPitch(pitch);
+                        spawner.angle = VectorAngle(-normal.x, -normal.y);
-                        spawner.A_SetAngle(angle);
                         spawner.actualDecalName = actualDecalName;
                         spawner.master = invoker.owner;
 
@@ -362,7 +357,7 @@ class SnekTechSprayer : HDWeapon
     }
 }
 
-class SnekTechSprayerDecalSpawner : Actor
+class SnekTechSprayerDecalSpawner : Decal
 {
     default
     {
@@ -376,14 +371,65 @@ class SnekTechSprayerDecalSpawner : Actor
         stop;
     }
 
-    int timeSinceLastSpray;
     int thisSprayerId;
     String actualDecalName;
 
+    Array<Thinker> decals;
+
+    void SpawnDecal()
+    {
+        Thinker think;
+        array<thinker> seen;
+
+        // find every decal that Isn't ours
+        let iter = ThinkerIterator.Create('Thinker', STAT_DECAL);
+        while (think = iter.Next()) {
+            // BaseDecal isn't exported to zscript so we have to filter this manually
+            if (think.GetClassName() == 'BaseDecal') {
+                seen.Push(think);
+            }
+        }
+
+        // pass the decal name as a map editor type of argument
+        args[0] = -int(name(actualDecalName));
+        // spawn the decal
+        Super.SpawnDecal();
+
+        // then find every decal that we spawned
+        iter.Reinit();
+        while (think = iter.Next()) {
+            if (think.GetClassName() == 'BaseDecal' &&
+                seen.Find(think) == seen.Size())
+            {
+                decals.Push(think);
+            }
+        }
+    }
+
+    override void OnDestroy()
+    {
+        for (let i = 0; i < decals.Size(); i++) {
+            if (decals[i]) {
+                decals[i].Destroy();
+            }
+        }
+    }
+
+    // Decal::BeginPlay deletes the actor
+    override void BeginPlay() {Actor.BeginPlay();}
+
     override void PostBeginPlay()
     {
         Super.PostBeginPlay();
-        A_SprayDecal(actualDecalName, KIRI_SPRAY_DISTANCE);
+
+        // copy A_SprayDecal z offset
+        setz(pos.z + height / 2);
+
+        SpawnDecal();
+        if (decals.Size() == 0) {
+            Destroy();
+            return;
+        }
 
         // Figure out a new ID number.
         ThinkerIterator iter = ThinkerIterator.Create("SnekTechSprayerDecalSpawner");
@@ -421,18 +467,6 @@ class SnekTechSprayerDecalSpawner : Actor
             }
         }
     }
-
-    override void Tick()
-    {
-        super.Tick();
-
-        timeSinceLastSpray++;
-
-        if(timeSinceLastSpray >= 35 * 60) {
-            A_SprayDecal(actualDecalName, KIRI_SPRAY_DISTANCE);
-            timeSinceLastSpray = 0;
-        }
-    }
 }
 
 class SnekTechSprayerPattern : Actor