Merge branch 'master' into cairocanvas

[ardour.git] / libs / canvas / wave_view.cc

diff --git a/libs/canvas/wave_view.cc b/libs/canvas/wave_view.cc
index b6d3a1c1dd10fe86cd53a74411fd9aebdd8604c1..3467672b88accf5d04700b432cf4c47dd8ccfcd8 100644 (file)
--- a/libs/canvas/wave_view.cc
+++ b/libs/canvas/wave_view.cc
@@ -44,6 +44,7 @@ using namespace ArdourCanvas;
 double WaveView::_global_gradient_depth = 0.6;
 bool WaveView::_global_logscaled = false;
 WaveView::Shape WaveView::_global_shape = WaveView::Normal;
+bool WaveView::_global_show_waveform_clipping = true;
 
 PBD::Signal0<void> WaveView::VisualPropertiesChanged;
 
@@ -177,7 +178,18 @@ WaveView::draw_image (PeakData* _peaks, int n_peaks) const
        Cairo::RefPtr<Cairo::Context> context = Cairo::Context::create (_image);
 
        boost::scoped_array<LineTips> tips (new LineTips[n_peaks]);
-       const double clip_level = 1.0;
+
+       /* Clip level nominally set to -0.9dBFS to account for inter-sample
+          interpolation possibly clipping (value may be too low).
+
+          We adjust by the region's own gain (but note: not by any gain
+          automation or its gain envelope) so that clip indicators are closer
+          to providing data about on-disk data. This multiplication is
+          needed because the data we get from AudioRegion::read_peaks()
+          has been scaled by scale_amplitude() already.
+       */
+
+       const double clip_level = 0.98853 * _region->scale_amplitude();
 
        if (_shape == WaveView::Rectified) {
 
@@ -328,35 +340,43 @@ WaveView::draw_image (PeakData* _peaks, int n_peaks) const
         * modelled on pyramix, except that we add clipping indicators.
         */
 
-       context->set_source_rgba (0, 0, 0, 1.0);
-
-       for (int i = 0; i < n_peaks; ++i) {
-               context->move_to (i, tips[i].top);
-
-               bool show_top_clip = (_shape == WaveView::Rectified && (tips[i].clip_max || tips[i].clip_min)) ||
-                       tips[i].clip_max;
-
-               if (show_top_clip) {
-                       context->set_source_rgba (1.0, 0, 0, 1.0);
-                       context->rel_line_to (0, 2.0);
-                       context->stroke ();
-                       context->set_source_rgba (0.0, 0, 0, 1.0);
-               } else {
-                       context->rel_line_to (0, 1.0);
-                       context->stroke ();
-               }
-
-               if (_shape != WaveView::Rectified) {
-                       context->move_to (i, tips[i].bot);
-                       if (tips[i].clip_min) {
+       if (_global_show_waveform_clipping) {
+               
+               context->set_source_rgba (0, 0, 0, 1.0);
+               
+               /* the height of the clip-indicator should be at most 7 pixels,
+                  or 5% of the height of the waveview item.
+               */
+               const double clip_height = min (7.0, ceil (_height * 0.05));
+               
+               for (int i = 0; i < n_peaks; ++i) {
+                       context->move_to (i, tips[i].top);
+                       
+                       bool show_top_clip = (_shape == WaveView::Rectified && (tips[i].clip_max || tips[i].clip_min)) ||
+                               tips[i].clip_max;
+                       
+                       if (show_top_clip) {
                                context->set_source_rgba (1.0, 0, 0, 1.0);
-                               context->rel_line_to (0, -2.0);
+                               context->rel_line_to (0, clip_height);
                                context->stroke ();
                                context->set_source_rgba (0.0, 0, 0, 1.0);
                        } else {
-                               context->rel_line_to (0, -1.0);
+                               context->rel_line_to (0, 1.0);
                                context->stroke ();
                        }
+
+                       if (_shape != WaveView::Rectified) {
+                               context->move_to (i, tips[i].bot);
+                               if (tips[i].clip_min) {
+                                       context->set_source_rgba (1.0, 0, 0, 1.0);
+                                       context->rel_line_to (0, -clip_height);
+                                       context->stroke ();
+                                       context->set_source_rgba (0.0, 0, 0, 1.0);
+                               } else {
+                                       context->rel_line_to (0, -1.0);
+                                       context->stroke ();
+                               }
+                       }
                }
        }
 
@@ -657,3 +677,13 @@ WaveView::set_global_gradient_depth (double depth)
                VisualPropertiesChanged (); /* EMIT SIGNAL */
        }
 }
+
+void
+WaveView::set_global_show_waveform_clipping (bool yn)
+{
+       if (_global_show_waveform_clipping != yn) {
+               _global_show_waveform_clipping = yn;
+               VisualPropertiesChanged (); /* EMIT SIGNAL */
+       }
+}
+