From 2d8b011bc8c6843d3bb55d4767e59b7129e8df73 Mon Sep 17 00:00:00 2001
From: Bill Currie <bill@taniwha.org>
Date: Sat, 16 Oct 2010 12:40:49 +0900
Subject: [PATCH] Support negative lights.

---
 tools/qflight/source/ltface.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/tools/qflight/source/ltface.c b/tools/qflight/source/ltface.c
index 6e75c42fc..b3d0cfbc6 100644
--- a/tools/qflight/source/ltface.c
+++ b/tools/qflight/source/ltface.c
@@ -340,16 +340,20 @@ SingleLightFace (entity_t *light, lightinfo_t *l)
 
 		switch (light->attenuation) {
 			case LIGHT_LINEAR:
-				add = light->light - dist;
+				add = fabs (light->light) - dist;
 				break;
 			case LIGHT_RADIUS:
-				add = light->light * (light->radius - dist) / light->radius;
+				add = fabs (light->light) * (light->radius - dist);
+				add /= light->radius;
 				break;
 			case LIGHT_INVERSE:
-				add = light->light / dist;
+				add = fabs (light->light) / dist;
 				break;
 			case LIGHT_REALISTIC:
-				add = light->light / (dist * dist);
+				add = fabs (light->light) / (dist * dist);
+				break;
+			case LIGHT_NO_ATTEN:
+				add = fabs (light->light);
 				break;
 			case LIGHT_LH:
 				add = 1 / (dist * dist * lightfalloff + LIGHTDISTBIAS);