Refactor visor expression/damage code

- Scope entire expression change code
- Use tables for related values
- Make certain variables and functions local

script.lua

@@ -3,13 +3,6 @@
 -- Texture dimensions --
 TEXTURE_WIDTH = 128
 TEXTURE_HEIGHT = 128
--- Values for UV mappings --
-face_damage=0
-face_expr=0
-step_u_face=32
-step_v_face=16
-offset_u_face=64
-offset_v_face=0
 armor_enabled=true
 vanilla_enabled=true
 
@@ -67,32 +60,39 @@ VANILLA_INNER={
 }
 
 -- Expression change -- {{{
-function getExprUV(damage, expression)
+do
-	local u=offset_u_face+(damage*step_u_face)
+	-- Values for UV mappings --
-	local v=offset_v_face+(expression*step_v_face)
+	expr_current={damage=0, expression=0}
-	return {u/TEXTURE_WIDTH,v/TEXTURE_HEIGHT}
+	local expr_step={u=32, v=16}
+	local expr_offset={u=64, v=0}
+
+	local function getExprUV(damage, expression)
+		local u=expr_offset.u+(damage*expr_step.u)
+		local v=expr_offset.v+(expression*expr_step.v)
+		return UV{u, v}
 	end
 	function changeExpression(_damage, _expression, ticks)
 		-- u is damage, v is expression
 		local damage = _damage
 		local expression = _expression
 		if damage == nil then
-		damage = face_damage
+			damage = expr_current.damage
 		end
 		if expression == nil then
-		expression = face_expr
+			expression = expr_current.expression
 		end
 
 		HEAD.setUV(getExprUV(damage,expression))
 		namedWait(ticks, resetExpression, "resetExpression")
 	end
 	function setExpression(damage, expression)
-	face_damage=damage
+		expr_current.damage=damage
-	face_expr=expression
+		expr_current.expression=expression
 		HEAD.setUV(getExprUV(damage, expression))
 	end
 	function resetExpression()
-	HEAD.setUV(getExprUV(face_damage,face_expr))
+		HEAD.setUV(getExprUV(expr_current.damage,expr_current.expression))
+	end
 end
 -- }}}
 
@@ -196,7 +196,7 @@ function tick()
 	-- optimization, only execute these once a second --
 	if world.getTimeOfDay() % 20 then
 		-- if face is cracked
-		if face_damage==1 and player.getHealth() > 5 then
+		if expr_current.damage==1 and player.getHealth() > 5 then
 			ping.healed()
 		end
 	end
@@ -236,5 +236,9 @@ function onCommand(input)
 			v.setEnabled(not v.getEnabled())
 		end
 	end
+	if input[1] == chat_prefix .. "test_expression" then
+		setExpression(input[2], input[3])
+		print(input[2] .. " " .. input[3])
+	end
 end