Add a bunch more statistics.

Now I know why sphere culling was a loss: 78% of all tested target portals
were trimmed by ClipToSeparators (50% eventually clipped away entirely).

tools/qfvis/include/vis.h

@@ -110,6 +110,12 @@ typedef struct {
 	int         portaltest;		///< number of portals tested via separators
 	int         portalpass;		///< number of portals through which vis passes
 	int         portalcheck;	///< number of portal checks
+	int         targettested;	///< number of times target portal tested
+	int         targettrimmed;	///< number of times target portal trimmed
+	int         targetclipped;	///< number of times target portal clipped away
+	int         sourcetested;	///< number of times source portal tested
+	int         sourcetrimmed;	///< number of times source portal trimmed
+	int         sourceclipped;	///< number of times source portal clipped away
 	int         chains;			///< number of visits to clusters
 	int         mighttest;		///< amount mightsee is used for masked tests
 	int         vistest;		///< amount visbits is used for masked tests

tools/qfvis/source/flow.c

@@ -355,17 +355,22 @@ RecursiveClusterFlow (int clusternum, threaddata_t *thread, pstack_t *prevstack)
 		}
 
 		thread->stats.portaltest++;
+		thread->stats.targettested++;
 
 		if (options.level > 0) {
 			// clip target to the image that would be formed by a laser
 			// pointing from the edges of source passing though the corners of
 			// pass
+			winding_t  *old = target;
 			target = ClipToSeparators (thread, &stack, source, prevstack->pass,
 									   target, 0);
 			if (!target) {
+				thread->stats.targetclipped++;
 				FreeWinding (source);
 				continue;
 			}
+			if (target != old)
+				thread->stats.targettrimmed++;
 		}
 
 		if (options.level > 1) {
@@ -375,32 +380,45 @@ RecursiveClusterFlow (int clusternum, threaddata_t *thread, pstack_t *prevstack)
 			// source shining past pass. eg, if source and pass are equilateral
 			// triangles rotated 60 (or 180) degrees relative to each other,
 			// parallel and in line, target will wind up being a hexagon.
+			winding_t  *old = target;
 			target = ClipToSeparators (thread, &stack, prevstack->pass, source,
 									   target, 1);
 			if (!target) {
+				thread->stats.targetclipped++;
 				FreeWinding (source);
 				continue;
 			}
+			if (target != old)
+				thread->stats.targettrimmed++;
 		}
 
+		thread->stats.sourcetested++;
 		// now do the same as for levels 1 and 2, but trimming source using
 		// the trimmed target
 		if (options.level > 2) {
+			winding_t  *old = source;
 			source = ClipToSeparators (thread, &stack, target, prevstack->pass,
 									   source, 2);
 			if (!source) {
+				thread->stats.sourceclipped++;
 				FreeWinding (target);
 				continue;
 			}
+			if (source != old)
+				thread->stats.sourcetrimmed++;
 		}
 
 		if (options.level > 3) {
+			winding_t  *old = source;
 			source = ClipToSeparators (thread, &stack, prevstack->pass, target,
 									   source, 3);
 			if (!source) {
+				thread->stats.sourceclipped++;
 				FreeWinding (target);
 				continue;
 			}
+			if (source != old)
+				thread->stats.sourcetrimmed++;
 		}
 
 		stack.source = source;

tools/qfvis/source/qfvis.c

@@ -306,6 +306,12 @@ PortalCompleted (threaddata_t *thread, portal_t *completed)
 	stats.portaltest += thread->stats.portaltest;
 	stats.portalpass += thread->stats.portalpass;
 	stats.portalcheck += thread->stats.portalcheck;
+	stats.targettested += thread->stats.targettested;
+	stats.targettrimmed += thread->stats.targettrimmed;
+	stats.targetclipped += thread->stats.targetclipped;
+	stats.sourcetested += thread->stats.sourcetested;
+	stats.sourcetrimmed += thread->stats.sourcetrimmed;
+	stats.sourceclipped += thread->stats.sourceclipped;
 	stats.chains += thread->stats.chains;
 	stats.mighttest += thread->stats.mighttest;
 	stats.vistest += thread->stats.vistest;
@@ -562,7 +568,12 @@ CalcPortalVis (void)
 	if (options.verbosity > 0) {
 		printf ("portalcheck: %i  portaltest: %i  portalpass: %i\n",
 				stats.portalcheck, stats.portaltest, stats.portalpass);
-		printf ("vistest: %i  mighttest: %i mightseeupdate: %i\n", stats.vistest, stats.mighttest, stats.mightseeupdate);
+		printf ("target trimmed: %d clipped: %d tested: %d\n",
+				stats.targettrimmed, stats.targetclipped, stats.targettested);
+		printf ("source trimmed: %d clipped: %d tested: %d\n",
+				stats.sourcetrimmed, stats.sourceclipped, stats.sourcetested);
+		printf ("vistest: %i  mighttest: %i mightseeupdate: %i\n",
+				stats.vistest, stats.mighttest, stats.mightseeupdate);
 	}
 }