Allow auto-probe grid size to be set on the command line

src/lightmap/lightmap.cpp

@@ -46,6 +46,7 @@
 
 extern int Multisample;
 extern int LightBounce;
+extern float GridSize;
 
 LightmapBuilder::LightmapBuilder()
 {
@@ -644,16 +645,15 @@ void LightmapBuilder::CreateLightProbes()
 	float maxX = std::floor(map->MaxX / 65536.0f) + 1.0f;
 	float maxY = std::floor(map->MaxY / 65536.0f) + 1.0f;
 
-	float gridSize = 32.0f;
+	float halfGridSize = GridSize * 0.5f;
-	float halfGridSize = gridSize * 0.5f;
 
 	std::vector<std::vector<LightProbeSample>> probes; // order probes by subsector
 	probes.resize(map->NumGLSubsectors);
 	size_t totalProbes = 0;
 
-	for (float y = minY; y < maxY; y += gridSize)
+	for (float y = minY; y < maxY; y += GridSize)
 	{
-		for (float x = minX; x < maxX; x += gridSize)
+		for (float x = minX; x < maxX; x += GridSize)
 		{
 			MapSubsectorEx* ssec = map->PointInSubSector((int)x, (int)y);
 			IntSector* sec = ssec ? map->GetSectorFromSubSector(ssec) : nullptr;
@@ -662,7 +662,7 @@ void LightmapBuilder::CreateLightProbes()
 				float z0 = sec->floorplane.zAt(x, y);
 				float z1 = sec->ceilingplane.zAt(x, y);
 				float startZ = (z1 - z0 < halfGridSize) ? (z0 + z1) * 0.5f : z0 + halfGridSize;
-				for (float z = startZ; z < z1; z += gridSize)
+				for (float z = startZ; z < z1; z += GridSize)
 				{
 					LightProbeSample probe;
 					probe.Position.x = x;

src/main.cpp

@@ -118,6 +118,7 @@ int				 LMDims = 1024;
 int				 Samples = 8;
 int				 Multisample = 1;
 int				 LightBounce = 0;
+float			 GridSize = 32.0f;
 
 // PRIVATE DATA DEFINITIONS ------------------------------------------------
 
@@ -157,6 +158,7 @@ static option long_opts[] =
 	{"size",			required_argument,	0,	'S'},
 	{"multisample",		required_argument,	0,	'M'},
 	{"bounce",			required_argument,	0,	'B'},
+	{"gridsize",		required_argument,	0,	'i'},
 	{0,0,0,0}
 };
 
@@ -457,6 +459,10 @@ static void ParseArgs(int argc, char **argv)
 			if (LightBounce < 0) LightBounce = 0;
 			if (LightBounce > 1) LightBounce = 1;
 			break;
+		case 'i':
+			GridSize = std::stof(optarg);
+			if (GridSize < 0.f) GridSize = 0.f;
+			break;
 		case 1000:
 			ShowUsage();
 			exit(0);
@@ -505,6 +511,9 @@ static void ShowUsage()
 		"                           must be in powers of two (1, 2, 4, 8, 16, etc)\n"
 		"  -M, --multisample=NNN    Number of samples to use per texel (default %d)\n"
 		"  -B, --bounce=NNN         Number of indirect light bounces (default %d, max 1)\n"
+		"  -i, --gridsize=NNN       Automatic light probe grid size, floating point\n"
+		"                           Lower values increase granularity at the expense of performance\n"
+		"                           Recommended: 32.0, 64.0, 128.0, etc (default %.1f)\n"
 		"  -w, --warn               Show warning messages\n"
 #if HAVE_TIMING
 		"  -t, --no-timing          Suppress timing information\n"
@@ -520,6 +529,7 @@ static void ShowUsage()
 		, (int)std::thread::hardware_concurrency()
 		, Multisample
 		, LightBounce
+		, GridSize
 	);
 }