From: Rudolf Polzer <divVerent@gmail.com>
Date: Sun, 19 Apr 2020 00:41:25 +0000 (+0200)
Subject: Comment ColorToBytesNonZero and fix zero detection in light.c.
X-Git-Url: https://git.xonotic.org/?a=commitdiff_plain;h=1b3887abb72be950ba6a39cd7d87b6ba3b20c8c3;p=xonotic%2Fnetradiant.git

Comment ColorToBytesNonZero and fix zero detection in light.c.
---

diff --git a/tools/quake3/q3map2/light.c b/tools/quake3/q3map2/light.c
index b8ad379f..709b2ab9 100644
--- a/tools/quake3/q3map2/light.c
+++ b/tools/quake3/q3map2/light.c
@@ -1771,7 +1771,7 @@ void TraceGrid( int num ){
 			}
 
 		/* vortex: apply gridscale and gridambientscale here */
-		if (gp->directed[0] || gp->directed[1] || gp->directed[2]) {
+		if (gp->directed[i][0] || gp->directed[i][1] || gp->directed[i][2]) {
 			/*
 			 * HACK: if there's a non-zero directed component, this
 			 * lightgrid cell is useful. However, ioq3 skips grid
diff --git a/tools/quake3/q3map2/light_ydnar.c b/tools/quake3/q3map2/light_ydnar.c
index 56539875..b86ff4b2 100644
--- a/tools/quake3/q3map2/light_ydnar.c
+++ b/tools/quake3/q3map2/light_ydnar.c
@@ -132,6 +132,12 @@ void ColorToBytes( const float *color, byte *colorBytes, float scale ){
 	colorBytes[ 2 ] = sample[ 2 ];
 }
 
+/*
+ * Same as ColorToBytes, but if the output color will never contain zero
+ * components. Used to avoid returning 0 0 0 due to an ioq3 issue. Reason
+ * to also map 0 0 1 to 1 1 1 is to ensure monotonicity in the color mapping
+ * to prevent banding-like artifacts on lightmaps.
+ */
 void ColorToBytesNonZero( const float *color, byte *colorBytes, float scale) {
 	int i;
 	ColorToBytes(color, colorBytes, scale);