added System.ocg/EnergyBar.c which provides AddEnergyBar() to show an energy bar over any object, adjusted Tutorial04 to use that

planet/System.ocg/EnergyBar.c

@@ -0,0 +1,61 @@
+/*
+	adds an energy bar above the object.
+	The energy bar uses either target.HitPoints & GetDamage() or target->GetMaxEnergy() & target->GetEnergy().
+*/
+global func AddEnergyBar()
+{
+	var e = AddEffect("ShowEnergyBar", this, 1, 0, nil, nil);
+	if (e)
+		return e.bar;
+}
+
+global func FxShowEnergyBarStart(target, effect, temp)
+{
+	if (temp) return;
+	var attachpoint = { x = 0, y = target->GetDefOffset(1) - 5};
+	var current, max;
+	if (target->GetCategory() & C4D_Living)
+	{
+		max = target->~GetMaxEnergy();
+		current = target->GetEnergy();
+	}
+	else
+	{
+		max = target.HitPoints;
+		current = max - target->GetDamage();
+	}
+	
+	if (current == nil || max == nil)
+		return -1;
+	
+	effect.bar = target->CreateProgressBar(GUI_ShadedSimpleProgressBar, max, current, 0, target->GetOwner(), attachpoint, nil, { width = 28, height = 6, color = RGB(200, 1, 1) });
+	effect.bar->SetPlane(750);
+	// update once
+	effect.Interval = 1;
+	
+	return 1;
+}
+
+global func FxShowEnergyBarTimer(target, effect, time)
+{
+	var value;
+	if (target->GetCategory() & C4D_Living) value = target->GetEnergy();
+	else value = target.HitPoints - target->GetDamage();
+	
+	effect.bar->SetValue(value);
+	effect.Interval = 0;
+	return 1;
+}
+
+global func FxShowEnergyBarDamage(target, effect, dmg, cause)
+{
+	effect.Interval = 1;
+	return dmg;
+}
+
+global func FxShowEnergyBarStop(target, effect, reason, temp)
+{
+	if (temp) return;
+	if (effect.bar)
+		effect.bar->Close();
+}

planet/Tutorial.ocf/Tutorial04.ocs/EnergyBar.ocd/DefCore.txt

@@ -1,9 +0,0 @@
-[DefCore]
-id=EnergyBar
-Category=C4D_StaticBack
-Width=32
-Height=32
-Offset=-16,-16
-Vertices=1
-VertexX=0
-VertexY=8

planet/Tutorial.ocf/Tutorial04.ocs/EnergyBar.ocd/Script.c

@@ -1,65 +0,0 @@
-/*-- 
-	Energy bars
-	Author: Maikel
-	
-	Displays an energy bar above an object, uses Library_Bars.
---*/
-
-
-#include Library_Bars
-
-private func EnergyBarWidth() { return 24; }
-private func EnergyBarHeight() { return 6; }
-
-protected func Initialize()
-{
-	return;
-}
-
-public func SetTarget(object target)
-{
-	// Attach energy bar to the object.
-	SetAction("Attach", target);
-	// Create energy bar.
-	SetBarLayers(2, 0);
-	SetBarOffset(0, - target->GetDefHeight() / 2, 0);
-	SetBarDimensions(EnergyBarWidth(), EnergyBarHeight(), 0);
-	SetClrModulation(RGB(200, 0, 0), 3);
-	UpdateEnergy();
-	return;
-}
-
-protected func UpdateEnergy()
-{
-	var target = GetActionTarget();
-	var energy = target->GetEnergy();
-	if (!energy)
-		return RemoveObject();
-	var phys = target->GetMaxEnergy();
-	var promille;
-	if (phys == 0) 
-		promille = 0;
-	else 
-		promille = 1000 * energy / phys;
-	SetBarProgress(promille, 0);	
-	return;
-}
-
-protected func AttachTargetLost() { RemoveObject(); }
-
-local Name = "$Name$";
-local ActMap = {
-	Attach = {
-		Prototype = Action,
-		Name = "Attach",
-		Procedure = DFA_ATTACH,
-		Length = 1,
-		Delay = 1,
-		X = 0,
-		Y = 0,
-		Wdt = 32,
-		Hgt = 32,
-		NextAction = "Attach",
-		StartCall = "UpdateEnergy",
-	},
-};

planet/Tutorial.ocf/Tutorial04.ocs/EnergyBar.ocd/StringTblDE.txt

@@ -1 +0,0 @@
-Name=Energy bar

planet/Tutorial.ocf/Tutorial04.ocs/EnergyBar.ocd/StringTblUS.txt

@@ -1 +0,0 @@
-Name=Energy bar

planet/Tutorial.ocf/Tutorial04.ocs/Script.c

@@ -111,7 +111,7 @@ private func InitializeScriptPlayer(int plr)
 	spearman1->CreateContents(Javelin);
 	spearman1->AI_GuardArea(800, 400, 400, 250);
 	AddEffect("IntContentRemoval", spearman1, 100, 0);
-	CreateObject(EnergyBar)->SetTarget(spearman1);
+	spearman1->AddEnergyBar();
 	
 	// Third section: Two opponents in a tower.
 	// Lower part: a weak spearman.
@@ -121,7 +121,7 @@ private func InitializeScriptPlayer(int plr)
 	spearman2->CreateContents(Javelin);
 	spearman2->AI_GuardArea(1350, 200, 500, 400);
 	AddEffect("IntContentRemoval", spearman2, 100, 0);
-	CreateObject(EnergyBar)->SetTarget(spearman2);
+	spearman2->AddEnergyBar();
 	// Upper part: a normal bowman.
 	var bowman = CreateObject(Clonk, 1732, 352, plr);
 	bowman->MakeCrewMember(plr);
@@ -129,7 +129,7 @@ private func InitializeScriptPlayer(int plr)
 	bowman->CreateContents(Bow)->CreateContents(Arrow);
 	bowman->AI_GuardArea(1350, 200, 500, 400);
 	AddEffect("IntContentRemoval", bowman, 100, 0);
-	CreateObject(EnergyBar)->SetTarget(bowman);
+	bowman->AddEnergyBar();
 	
 	// Fourth section: Opponent with sword and shield.
 	var swordman = CreateObject(Clonk, 2250, 360, plr);
@@ -139,7 +139,7 @@ private func InitializeScriptPlayer(int plr)
 	swordman->CreateContents(Sword);
 	swordman->AI_GuardArea(2050, 300, 300, 100);
 	AddEffect("IntContentRemoval", swordman, 100, 0);
-	CreateObject(EnergyBar)->SetTarget(swordman);
+	swordman->AddEnergyBar();
 	return;
 }