simplify zooming, remove Editor::clamp_samples_per_pixel(), fix getting "stuck" at max and min zoom levels

gtk2_ardour/editor.cc

@@ -3335,7 +3335,7 @@ Editor::cycle_edit_mode ()
 			Config->set_edit_mode (Ripple);
 		}
 		break;
-//	case Splice:
+	case Splice:
 	case Ripple:
 		Config->set_edit_mode (Lock);
 		break;
@@ -4056,8 +4056,6 @@ Editor::reset_y_origin (double y)
 void
 Editor::reset_zoom (framecnt_t spp)
 {
-	clamp_samples_per_pixel (spp);
-
 	if (spp == samples_per_pixel) {
 		return;
 	}
@@ -4169,12 +4167,26 @@ Editor::use_visual_state (VisualState& vs)
 
 /** This is the core function that controls the zoom level of the canvas. It is called
  *  whenever one or more calls are made to reset_zoom().  It executes in an idle handler.
- *  @param fpu New frames per unit; should already have been clamped so that it is sensible.
+ *  @param spp new number of samples per pixel
  */
 void
 Editor::set_samples_per_pixel (framecnt_t spp)
 {
-	clamp_samples_per_pixel (spp);
+	if (spp < 1) {
+		return;
+	}
+
+	const framecnt_t three_days = 3 * 24 * 60 * 60 * (_session ? _session->frame_rate() : 48000);
+	const framecnt_t lots_of_pixels = 4000;
+
+	/* if the zoom level is greater than what you'd get trying to display 3
+	 * days of audio on a really big screen, then it's too big.
+	 */
+
+	if (spp * lots_of_pixels > three_days) {
+		return;
+	}
+
 	samples_per_pixel = spp;
 
 	if (tempo_lines) {

gtk2_ardour/editor.h

@@ -520,7 +520,6 @@ class Editor : public PublicEditor, public PBD::ScopedConnectionList, public ARD
 	Editing::ZoomFocus zoom_focus;
 
 	void set_samples_per_pixel (framecnt_t);
-        bool clamp_samples_per_pixel (framecnt_t &) const;
 
 	Editing::MouseMode mouse_mode;
 	Editing::MouseMode pre_internal_mouse_mode;

gtk2_ardour/editor_ops.cc

@@ -1448,38 +1448,6 @@ Editor::tav_zoom_smooth (bool coarser, bool force_all)
 	}
 }
 
-bool
-Editor::clamp_samples_per_pixel (framecnt_t& fpp) const
-{
-	bool clamped = false;
-	
-	if (fpp < 1) {
-		fpp = 1;
-		clamped = true;
-	}
-
-	framecnt_t sr;
-
-	if (_session) {
-		sr = _session->frame_rate ();
-	} else {
-		sr = 48000;
-	}
-
-	const framecnt_t three_days = 3 * 24 * 60 * 60 * sr;
-	const framecnt_t lots_of_pixels = 4000;
-
-	/* if the zoom level is greater than what you'd get trying to display 3
-	 * days of audio on a really big screen, scale it down.
-	 */
-
-	if (fpp * lots_of_pixels > three_days) {
-		fpp = three_days / _track_canvas->width();
-		clamped = true;
-	}
-
-	return clamped;
-}
 
 void
 Editor::temporal_zoom_step (bool coarser)
@@ -1516,7 +1484,6 @@ Editor::temporal_zoom (framecnt_t fpp)
 	framecnt_t nfpp;
 	double l;
 
-	clamp_samples_per_pixel (fpp);
 	if (fpp == samples_per_pixel) {
 		return;
 	}
@@ -1806,8 +1773,7 @@ Editor::temporal_zoom_to_frame (bool coarser, framepos_t frame)
 			new_spp = samples_per_pixel - (samples_per_pixel/2);
 		} else {
 			/* could bail out here since we cannot zoom any finer,
-			   but leave that to the clamp_samples_per_pixel() and
+			   but leave that to the equality test below
-			   equality test below
 			*/
 			new_spp = samples_per_pixel;
 		}
@@ -1815,8 +1781,6 @@ Editor::temporal_zoom_to_frame (bool coarser, framepos_t frame)
 		range_before -= range_before/2;
 	}
 
-	clamp_samples_per_pixel (new_spp);
-
 	if (new_spp == samples_per_pixel)  {
 		return;
 	}