diff --git a/tools/quake3/common/qmath.h b/tools/quake3/common/qmath.h
index 0e9cc292..d3d71e81 100644
--- a/tools/quake3/common/qmath.h
+++ b/tools/quake3/common/qmath.h
@@ -27,6 +27,9 @@ struct MinMax___
 		mins.x() = mins.y() = mins.z() = std::numeric_limits<T>::max();
 		maxs.x() = maxs.y() = maxs.z() = std::numeric_limits<T>::lowest();
 	}
+	bool valid() const {
+		return mins.x() < maxs.x() && mins.y() < maxs.y() && mins.z() < maxs.z();
+	}
 	template<typename U>
 	void extend( const BasicVector3<U>& point ){
 		for ( size_t i = 0; i < 3; ++i ){
diff --git a/tools/quake3/q3map2/light.cpp b/tools/quake3/q3map2/light.cpp
index 253e7541..d894d85b 100644
--- a/tools/quake3/q3map2/light.cpp
+++ b/tools/quake3/q3map2/light.cpp
@@ -113,7 +113,7 @@ static void CreateSunLight( sun_t *sun ){
 		light->style = noStyles ? LS_NORMAL : sun->style;
 
 		/* set the light's position out to infinity */
-		light->origin = -direction * ( MAX_WORLD_COORD * 8.0f );    /* MAX_WORLD_COORD * 2.0f */
+		light->origin = direction * ( MAX_WORLD_COORD * 8.0f );    /* MAX_WORLD_COORD * 2.0f */
 
 		/* set the facing to be the inverse of the sun direction */
 		light->normal = -direction;
diff --git a/tools/quake3/q3map2/shaders.cpp b/tools/quake3/q3map2/shaders.cpp
index 57a7a709..da316e14 100644
--- a/tools/quake3/q3map2/shaders.cpp
+++ b/tools/quake3/q3map2/shaders.cpp
@@ -1120,10 +1120,8 @@ static void ParseShaderFile( const char *filename ){
 					GetTokenAppend( shaderText, false );   amp = atof( token );
 
 					/* calculate */
-					const Vector3 mins = amt * base;
-					const Vector3 maxs = amt * amp + mins;
-					si->minmax.mins += mins;
-					si->minmax.maxs += maxs;
+					si->minmax.mins = amt * base;
+					si->minmax.maxs = amt * amp + si->minmax.mins;
 				}
 			}
 
diff --git a/tools/quake3/q3map2/surface.cpp b/tools/quake3/q3map2/surface.cpp
index 69d84db1..44d4afc9 100644
--- a/tools/quake3/q3map2/surface.cpp
+++ b/tools/quake3/q3map2/surface.cpp
@@ -1999,10 +1999,7 @@ int FilterWindingIntoTree_r( winding_t *w, mapDrawSurface_t *ds, node_t *node ){
 	si = ds->shaderInfo;
 
 	/* ydnar: is this the head node? */
-	if ( node->parent == NULL && si != NULL &&
-		 ( si->minmax.mins[ 0 ] != 0.0f || si->minmax.maxs[ 0 ] != 0.0f ||
-		   si->minmax.mins[ 1 ] != 0.0f || si->minmax.maxs[ 1 ] != 0.0f ||
-		   si->minmax.mins[ 2 ] != 0.0f || si->minmax.maxs[ 2 ] != 0.0f ) ) {
+	if ( node->parent == NULL && si != NULL && si->minmax.valid() ) {
 		static bool warned = false;
 		if ( !warned ) {
 			Sys_Warning( "this map uses the deformVertexes move hack\n" );
diff --git a/tools/quake3/q3map2/writebsp.cpp b/tools/quake3/q3map2/writebsp.cpp
index ff64a05c..2576d8b9 100644
--- a/tools/quake3/q3map2/writebsp.cpp
+++ b/tools/quake3/q3map2/writebsp.cpp
@@ -560,7 +560,7 @@ void BeginModel( void ){
 	}
 
 	/* ydnar: lightgrid mins/maxs */
-	if ( lgMinmax.mins[ 0 ] < 99999 ) {
+	if ( lgMinmax.valid() ) {
 		/* use lightgrid bounds */
 		mod->minmax = lgMinmax;
 	}
@@ -572,7 +572,8 @@ void BeginModel( void ){
 
 	/* note size */
 	Sys_FPrintf( SYS_VRB, "BSP bounds: { %f %f %f } { %f %f %f }\n", minmax.mins[0], minmax.mins[1], minmax.mins[2], minmax.maxs[0], minmax.maxs[1], minmax.maxs[2] );
-	Sys_FPrintf( SYS_VRB, "Lightgrid bounds: { %f %f %f } { %f %f %f }\n", lgMinmax.mins[0], lgMinmax.mins[1], lgMinmax.mins[2], lgMinmax.maxs[0], lgMinmax.maxs[1], lgMinmax.maxs[2] );
+	if ( lgMinmax.valid() )
+		Sys_FPrintf( SYS_VRB, "Lightgrid bounds: { %f %f %f } { %f %f %f }\n", lgMinmax.mins[0], lgMinmax.mins[1], lgMinmax.mins[2], lgMinmax.maxs[0], lgMinmax.maxs[1], lgMinmax.maxs[2] );
 
 	/* set firsts */
 	mod->firstBSPSurface = numBSPDrawSurfaces;