Unify clamping of frames-per-unit values during zoom; should help with #3514.

git-svn-id: svn://localhost/ardour2/branches/3.0@12796 d708f5d6-7413-0410-9779-e7cbd77b26cf

1 files changed, 25 insertions, 8 deletions

diff --git a/gtk2_ardour/editor_ops.cc b/gtk2_ardour/editor_ops.cc
index eacf0c51bd..46a69ce6af 100644
--- a/gtk2_ardour/editor_ops.cc
+++ b/gtk2_ardour/editor_ops.cc
@@ -1327,14 +1327,30 @@ Editor::tav_zoom_smooth (bool coarser, bool force_all)
 	_routes->resume_redisplay ();
 }
 
+bool
+Editor::clamp_frames_per_unit (double& fpu) const
+{
+	bool clamped = false;
+	
+	if (fpu < 2.0) {
+		fpu = 2.0;
+		clamped = true;
+	}
+
+	if (max_framepos / fpu < 800) {
+		fpu = max_framepos / 800.0;
+		clamped = true;
+	}
+
+	return clamped;
+}
+
 void
 Editor::temporal_zoom_step (bool coarser)
 {
 	ENSURE_GUI_THREAD (*this, &Editor::temporal_zoom_step, coarser)
 
-	double nfpu;
-
-	nfpu = frames_per_unit;
+	double nfpu = frames_per_unit;
 
 	if (coarser) {
 		nfpu = min (9e6, nfpu * 1.61803399);
@@ -1346,9 +1362,11 @@ Editor::temporal_zoom_step (bool coarser)
 }
 
 void
-Editor::temporal_zoom (gdouble fpu)
+Editor::temporal_zoom (double fpu)
 {
-	if (!_session) return;
+	if (!_session) {
+		return;
+	}
 
 	framepos_t current_page = current_page_frames();
 	framepos_t current_leftmost = leftmost_frame;
@@ -1362,9 +1380,8 @@ Editor::temporal_zoom (gdouble fpu)
 	double nfpu;
 	double l;
 
-	/* XXX this limit is also in ::set_frames_per_unit() */
-
-	if (frames_per_unit <= 1.0 && fpu <= frames_per_unit) {
+	clamp_frames_per_unit (fpu);
+	if (fpu == frames_per_unit) {
 		return;
 	}