From b683e47499fc7568e50bf3c2bacdf64a95f6b1ea Mon Sep 17 00:00:00 2001
From: Sven Eberhardt <sven2@goldwipf.de>
Date: Wed, 16 Sep 2015 21:13:00 -0400
Subject: [PATCH] Add LightOffset property to allow light sources to origin
 from locations other than the object center.

---
 docs/sdk/script/fn/SetLightRange.xml | 10 ++++++++++
 src/landscape/fow/C4FoWLight.cpp     | 10 +++++++++-
 src/script/C4StringTable.cpp         |  1 +
 src/script/C4StringTable.h           |  1 +
 4 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/docs/sdk/script/fn/SetLightRange.xml b/docs/sdk/script/fn/SetLightRange.xml
index 01cf6cec1..744f7955f 100644
--- a/docs/sdk/script/fn/SetLightRange.xml
+++ b/docs/sdk/script/fn/SetLightRange.xml
@@ -24,6 +24,7 @@
       </params>
     </syntax>
     <desc>Sets the light reach of the object. When a clonk is added to the crew via <funclink>MakeCrewMember</funclink>, a light is added automatically with the default range of 300 and a fadeout of 80.</desc>
+    <remark>A local offset for the light center can be defined by setting the object property LightRange to an array with two elements for X- and Y-offset respectively.</remark>
     <examples>
       <example>
         <code>func ControlUse(object clonk)
@@ -34,6 +35,15 @@
 }</code>
         <text>Confused the acid phile with the eye drops, did ya?</text>
       </example>
+      <example>
+        <code>func Construction()
+{
+	SetLightRange(100, 100);
+	this.LightRange = [0,-100];
+	return true;
+}</code>
+        <text>Script for a lamp post. A light coming from 100 pixel above the object center is enabled when the object is created.</text>
+      </example>
     </examples>
     <related>
       <funclink>SetPlrView</funclink>
diff --git a/src/landscape/fow/C4FoWLight.cpp b/src/landscape/fow/C4FoWLight.cpp
index 036ca24b9..248b3b4f4 100644
--- a/src/landscape/fow/C4FoWLight.cpp
+++ b/src/landscape/fow/C4FoWLight.cpp
@@ -96,8 +96,16 @@ void C4FoWLight::SetColor(uint32_t iValue)
 
 void C4FoWLight::Update(C4Rect Rec)
 {
-	// Update position from object. Clear if we moved in any way
+	// Update position from object.
 	int32_t iNX = fixtoi(pObj->fix_x), iNY = fixtoi(pObj->fix_y);
+	// position may be affected by LightOffset property
+	C4ValueArray *light_offset = pObj->GetPropertyArray(P_LightOffset);
+	if (light_offset)
+	{
+		iNX += light_offset->GetItem(0).getInt();
+		iNY += light_offset->GetItem(1).getInt();
+	}
+	// Clear if we moved in any way
 	if (iNX != iX || iNY != iY)
 	{
 		for(size_t i = 0; i < sections.size(); ++i )
diff --git a/src/script/C4StringTable.cpp b/src/script/C4StringTable.cpp
index 71c629e91..a895ecf2c 100644
--- a/src/script/C4StringTable.cpp
+++ b/src/script/C4StringTable.cpp
@@ -236,6 +236,7 @@ C4StringTable::C4StringTable()
 	P[P_Equalizer_Mid2_Width] = "Equalizer_Mid2_Width";
 	P[P_Equalizer_High_Gain] = "Equalizer_High_Gain";
 	P[P_Equalizer_High_Cutoff] = "Equalizer_High_Cutoff";
+	P[P_LightOffset] = "LightOffset";
 	P[DFA_WALK] = "WALK";
 	P[DFA_FLIGHT] = "FLIGHT";
 	P[DFA_KNEEL] = "KNEEL";
diff --git a/src/script/C4StringTable.h b/src/script/C4StringTable.h
index 64990665f..3f1ca44a4 100644
--- a/src/script/C4StringTable.h
+++ b/src/script/C4StringTable.h
@@ -438,6 +438,7 @@ enum C4PropertyName
 	P_Equalizer_Mid2_Width,
 	P_Equalizer_High_Gain,
 	P_Equalizer_High_Cutoff,
+	P_LightOffset,
 // Default Action Procedures
 	DFA_WALK,
 	DFA_FLIGHT,