da33d70c10ddaae6c3290cb900d7d0cc2b6ee01b
hiram
  Tue Mar 17 13:57:24 2026 -0700
allow calculation of GC percent on the fly with code help from claude refs #35958

diff --git src/hg/hgTracks/hgTracks.h src/hg/hgTracks/hgTracks.h
index 078220f16cf..f50387672d3 100644
--- src/hg/hgTracks/hgTracks.h
+++ src/hg/hgTracks/hgTracks.h
@@ -1202,30 +1202,35 @@
 /* Return linked features from range of table with the scores scaled appropriately */
 
 void ctWigLoadItems(struct track *tg);
 /*	load custom wiggle track data	*/
 void wigLoadItems(struct track *tg);
 /*	load wiggle track data from database	*/
 void wigMethods(struct track *track, struct trackDb *tdb,
                                 int wordCount, char *words[]);
 /* Set up wig pointers and do some other precalculations on a wig type track. */
 void bedGraphMethods(struct track *track, struct trackDb *tdb,
 	int wordCount, char *words[]);
 void bigWigMethods(struct track *track, struct trackDb *tdb,
 	int wordCount, char *words[]);
 /* Make track group for wig - wiggle tracks. */
 
+struct track *gc5BaseOnTheFlyTg(struct cart *cart);
+/* Create an on-the-fly GC percent track computed directly from
+ *     from genome sequence.
+ */
+
 void mathWigMethods(struct track *track, struct trackDb *tdb, 
 	int wordCount, char *words[]);
 /* mathWig load and draw methods. */
 
 void bigRmskMethods(struct track *track, struct trackDb *tdb,
                                 int wordCount, char *words[]);
 /* Set up bigRmsk methods. */
 
 void commonBigBedMethods(struct track *track, struct trackDb *tdb,
                                 int wordCount, char *words[]);
 /* Set up common bigBed methods used by several track types that depend on the bigBed format. */
 
 void bigBedMethods(struct track *track, struct trackDb *tdb,
                                 int wordCount, char *words[]);
 /* Set up bigBed methods for tracks that are type bigBed. */