horse: use straight front type in racecourse api

mdb/racecourse.go

@@ -139,9 +139,8 @@ func spansslopes(id horse.RacecourseID, evts []courseEvent, length float32) ([]h
 			}
 			// Start of the straight.
 			span = horse.RacecourseSpan{
-				Start:       evt.Distance,
-				Straight:    true,
-				FarStraight: evt.Values[1] == 2,
+				Start:    evt.Distance,
+				Straight: int8(evt.Values[1]),
 			}
 			// Continue out of the switch.
 		}
@@ -154,7 +153,7 @@ func spansslopes(id horse.RacecourseID, evts []courseEvent, length float32) ([]h
 			// Longchamp 1000 (which doesn't appear to actually be used but w/e)
 			// defines straights by their start positions only, so check for the
 			// previous event being a straight with no end.
-			if prev.Straight && prev.End == 0 {
+			if prev.Straight != 0 && prev.End == 0 {
 				spans[len(spans)-1].End = span.Start
 			} else {
 				// Otherwise, insert a new span which is neither straight nor corner.