Add the solid-sky option from Jardrup's light tool.

However, actual sky tracing is not yet implemented.

tools/qflight/include/light.h

@@ -122,6 +122,8 @@ extern vec3_t *surfaceorgs;
 extern struct entity_s **novislights;
 extern int num_novislights;
 
+const char *get_tex_name (int texindex);
+
 //@}
 
 #endif// __light_h

tools/qflight/include/options.h

@@ -41,6 +41,7 @@ typedef struct {
 	int         novis;
 	int         extrabit;
 	int         attenuation;
+	int         solid_sky;
 	vec_t       extrascale;
 	vec_t		distance;
 	vec_t		range;

tools/qflight/source/ltface.c

@@ -61,6 +61,24 @@
 int c_bad;
 int c_culldistplane, c_proper;
 
+const char *
+get_tex_name (int texindex)
+{
+	dmiptexlump_t *mtl;
+	miptex_t   *mt;
+	int         miptex;
+
+	if (bsp->texdatasize) {
+		mtl = (dmiptexlump_t *) bsp->texdata;
+		miptex = bsp->texinfo[texindex].miptex;
+		if (mtl->dataofs[miptex] != -1) {
+			mt = (miptex_t *) (bsp->texdata + mtl->dataofs[miptex]);
+			return mt->name;
+		}
+	}
+	return "notex";
+}
+
 /*
 SAMPLE POINT DETERMINATION
 

tools/qflight/source/options.c

@@ -65,6 +65,7 @@ static struct option const long_options[] = {
 	{"distance", required_argument, 0, 'd'},
 	{"range", required_argument, 0, 'r'},
 	{"file", required_argument, 0, 'f'},
+	{"solid-sky", no_argument, 0, 'S'},
 	{NULL, 0, NULL, 0}
 };
 
@@ -83,6 +84,7 @@ static const char *short_options =
 	"r:"	// scale range
 	"P:"	// properties file
 	"f:"
+	"S"		// solid-sky
 	;
 
 void
@@ -106,7 +108,9 @@ usage (int status)
 		"    -n, --noise [factor]      Scale noise. 0 (default) to disable\n"
 		"    -c, --cutoff [scale]      Scale cutoff. 0 to disable\n"
 		"    -P, --properties [file]   Properties file\n"
-		"    -f, --file [bspfile]      BSP file\n\n");
+		"    -f, --file [bspfile]      BSP file\n"
+		"    -S, --solid-sky           Enable solid sky brushes\n"
+		"\n");
 	exit (status);
 }
 
@@ -188,6 +192,8 @@ DecodeArgs (int argc, char **argv)
 			case 'P':
 				options.properties_filename = strdup (optarg);
 				break;
+			case 'S':
+				options.solid_sky = true;
 			default:
 				usage (1);
 		}

tools/qflight/source/trace.c

@@ -49,7 +49,9 @@
 #include "QF/dstring.h"
 #include "QF/quakefs.h"
 #include "QF/sys.h"
+
 #include "light.h"
+#include "options.h"
 
 typedef struct {
 	int         type;
@@ -98,9 +100,14 @@ MakeTnode (int nodenum)
 	t->dist = plane->dist;
 
 	for (i = 0; i < 2; i++) {
-		if (node->children[i] < 0)
+		if (node->children[i] < 0) {
 			t->children[i] = bsp->leafs[-node->children[i] - 1].contents;
-		else {
+			if (options.solid_sky && t->children[i] == CONTENTS_SOLID) {
+				dface_t    *face = &bsp->faces[node->firstface];
+				if (!strncmp (get_tex_name (face->texinfo), "sky", 3))
+					t->children[i] = CONTENTS_SKY;	// Simulate real sky
+			}
+		} else {
 			t->children[i] = tnode_p - tnodes;
 			MakeTnode (node->children[i]);
 		}