Tempo ramps - add Canvas::FramedCurve and use it in the tempo marker bar.
authornick_m <mainsbridge@gmail.com>
Tue, 17 May 2016 17:26:18 +0000 (03:26 +1000)
committernick_m <mainsbridge@gmail.com>
Fri, 27 May 2016 13:38:16 +0000 (23:38 +1000)
gtk2_ardour/tempo_curve.cc
gtk2_ardour/tempo_curve.h
libs/canvas/canvas/framed_curve.h [new file with mode: 0644]
libs/canvas/framed_curve.cc [new file with mode: 0644]
libs/canvas/wscript

index 37feb9870dd32430957469d51302270890ff4cf6..8f19001357ff174b32a755bbea4552e6bd25f4a0 100644 (file)
@@ -24,7 +24,7 @@ static double curve_height = 13.0;
 
 void TempoCurve::setup_sizes(const double timebar_height)
 {
-       curve_height = floor (timebar_height) - 2;
+       curve_height = floor (timebar_height) - 2.5;
 }
 
 TempoCurve::TempoCurve (PublicEditor& ed, ArdourCanvas::Container& parent, guint32 rgba, ARDOUR::TempoSection& temp, framepos_t frame, bool handle_events)
@@ -38,36 +38,28 @@ TempoCurve::TempoCurve (PublicEditor& ed, ArdourCanvas::Container& parent, guint
        , _max_tempo (temp.beats_per_minute())
        , _tempo (temp)
 
-
 {
-
-       points = new ArdourCanvas::Points ();
-       points->push_back (ArdourCanvas::Duple (0.0, 0.0));
-       points->push_back (ArdourCanvas::Duple (1.0, 0.0));
-       points->push_back (ArdourCanvas::Duple (1.0, curve_height));
-       points->push_back (ArdourCanvas::Duple (0.0, curve_height));
-
        frame_position = frame;
        unit_position = editor.sample_to_pixel (frame);
 
-       group = new ArdourCanvas::Container (&parent, ArdourCanvas::Duple (unit_position, 0));
+       group = new ArdourCanvas::Container (&parent, ArdourCanvas::Duple (unit_position, 1));
 #ifdef CANVAS_DEBUG
        group->name = string_compose ("Marker::group for %1", _tempo.beats_per_minute());
 #endif
 
-       _background = new ArdourCanvas::Rectangle (group);
-#ifdef CANVAS_DEBUG
-       _background->name = string_compose ("TempoCurve::_background for %1", _tempo.beats_per_minute());
-#endif
-       _background->set_x0 (0.0);
-       _background->set_x1 (ArdourCanvas::COORD_MAX);
-       _background->set_outline_what (ArdourCanvas::Rectangle::What(0));
-       _curve = new ArdourCanvas::Curve (group);
+       _curve = new ArdourCanvas::FramedCurve (group);
 #ifdef CANVAS_DEBUG
        _curve->name = string_compose ("TempoCurve::_curve for %1", _tempo.beats_per_minute());
 #endif
-       _curve->set_fill_mode (ArdourCanvas::Curve::Inside);
-       _curve->set_points_per_segment (32);
+       _curve->set_fill_mode (ArdourCanvas::FramedCurve::Inside);
+       _curve->set_points_per_segment (31);
+
+       points = new ArdourCanvas::Points ();
+       points->push_back (ArdourCanvas::Duple (0.0, 0.0));
+       points->push_back (ArdourCanvas::Duple (1.0, 0.0));
+       points->push_back (ArdourCanvas::Duple (1.0, curve_height));
+       points->push_back (ArdourCanvas::Duple (0.0, curve_height));
+
        _curve->set (*points);
 
        set_color_rgba (rgba);
@@ -79,7 +71,6 @@ TempoCurve::TempoCurve (PublicEditor& ed, ArdourCanvas::Container& parent, guint
         */
 
        _curve->set_data ("tempo curve", this);
-       _background->set_data ("tempo curve", this);
 
        if (handle_events) {
                //group->Event.connect (sigc::bind (sigc::mem_fun (editor, &PublicEditor::canvas_marker_event), group, this));
@@ -87,7 +78,6 @@ TempoCurve::TempoCurve (PublicEditor& ed, ArdourCanvas::Container& parent, guint
 
        set_position (_tempo.frame(), UINT32_MAX);
        _curve->Event.connect (sigc::bind (sigc::mem_fun (editor, &PublicEditor::canvas_tempo_curve_event), _curve, this));
-       _background->Event.connect (sigc::bind (sigc::mem_fun (editor, &PublicEditor::canvas_tempo_curve_event), _background, this));
 
 }
 
@@ -120,7 +110,6 @@ TempoCurve::the_item() const
 void
 TempoCurve::set_position (framepos_t frame, framepos_t end_frame)
 {
-       points->clear();
        unit_position = editor.sample_to_pixel (frame);
        group->set_x_position (unit_position);
        frame_position = frame;
@@ -128,40 +117,40 @@ TempoCurve::set_position (framepos_t frame, framepos_t end_frame)
 
        const double tempo_delta = max (10.0, _max_tempo - _min_tempo);
        double max_y = 0.0;
+
+       points->clear();
+
        points = new ArdourCanvas::Points ();
+       points->push_back (ArdourCanvas::Duple (0.0, curve_height));
 
        if (end_frame == UINT32_MAX) {
-               _curve->set_fill_mode (ArdourCanvas::Curve::None);
                const double tempo_at = _tempo.tempo_at_frame (frame, editor.session()->frame_rate()) * _tempo.note_type();
-               const double y2_pos =  (curve_height + 2.0) - (((tempo_at - _min_tempo) / (tempo_delta)) * curve_height);
-               max_y = y2_pos;
-               points->push_back (ArdourCanvas::Duple (0.0, y2_pos));
-               points->push_back (ArdourCanvas::Duple (ArdourCanvas::COORD_MAX - 5.0, y2_pos));
+               const double y_pos =  (curve_height) - (((tempo_at - _min_tempo) / (tempo_delta)) * curve_height);
+
+               max_y = y_pos;
+
+               points->push_back (ArdourCanvas::Duple (0.0, y_pos));
+               points->push_back (ArdourCanvas::Duple (ArdourCanvas::COORD_MAX - 5.0, y_pos));
 
        } else {
-               _curve->set_fill_mode (ArdourCanvas::Curve::Inside);
-               const framepos_t frame_step = (end_frame - frame) / 32;
+               const framepos_t frame_step = (end_frame - frame) / 31;
                framepos_t current_frame = frame;
+
                while (current_frame < end_frame) {
                        const double tempo_at = _tempo.tempo_at_frame (current_frame, editor.session()->frame_rate()) * _tempo.note_type();
-                       const double y2_pos = (curve_height + 2.0) - (((tempo_at - _min_tempo) / (tempo_delta)) * curve_height);
+                       const double y_pos = (curve_height) - (((tempo_at - _min_tempo) / (tempo_delta)) * curve_height);
 
-                       points->push_back (ArdourCanvas::Duple (editor.sample_to_pixel (current_frame - frame), y2_pos));
-                       max_y = max (y2_pos, max_y);
+                       points->push_back (ArdourCanvas::Duple (editor.sample_to_pixel (current_frame - frame), y_pos));
+
+                       max_y = max (y_pos, max_y);
                        current_frame += frame_step;
                }
-       }
+               if (current_frame != end_frame) {
+                       const double tempo_at = _tempo.tempo_at_frame (end_frame, editor.session()->frame_rate()) * _tempo.note_type();
+                       const double y_pos = (curve_height) - (((tempo_at - _min_tempo) / (tempo_delta)) * curve_height);
 
-       /* the background fills the gap between the bottom of the curve and the time bar */
-       _background->set_x0 (0.0);
-       _background->set_x1 (editor.sample_to_pixel (end_frame - frame));
-       _background->set_y0 (max_y + 1.0);
-       _background->set_y1 (curve_height + 2.0);
-
-       if (max_y == curve_height + 2.0) {
-               _background->hide();
-       } else {
-               _background->show();
+                       points->push_back (ArdourCanvas::Duple (editor.sample_to_pixel (end_frame - frame), y_pos));
+               }
        }
 
        _curve->set (*points);
@@ -196,6 +185,4 @@ TempoCurve::set_color_rgba (uint32_t c)
        _curve->set_fill_color (UIConfiguration::instance().color_mod ("selection rect", "selection rect"));
        _curve->set_outline_color (_color);
 
-       _background->set_fill (true);
-       _background->set_fill_color (UIConfiguration::instance().color_mod ("selection rect", "selection rect"));
 }
index 91311a3be60e28dab380c94fd5a2a0cd2b9a71bf..dc678e4a6cb6d859d959aa4072ded4901398a2eb 100644 (file)
@@ -10,6 +10,7 @@
 #include "pbd/signals.h"
 
 #include "canvas/types.h"
+#include "canvas/framed_curve.h"
 
 namespace ARDOUR {
        class TempoSection;
@@ -50,8 +51,7 @@ protected:
        ArdourCanvas::Container* _parent;
        ArdourCanvas::Container *group;
        ArdourCanvas::Points *points;
-       ArdourCanvas::Rectangle* _background;
-       ArdourCanvas::Curve* _curve;
+       ArdourCanvas::FramedCurve* _curve;
 
        double        unit_position;
        framepos_t    frame_position;
diff --git a/libs/canvas/canvas/framed_curve.h b/libs/canvas/canvas/framed_curve.h
new file mode 100644 (file)
index 0000000..9e99c59
--- /dev/null
@@ -0,0 +1,66 @@
+/*
+    Copyright (C) 2013 Paul Davis
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#ifndef __CANVAS_FRAMED_CURVE_H__
+#define __CANVAS_FRAMED_CURVE_H__
+
+#include "canvas/visibility.h"
+
+#include "canvas/interpolated_curve.h"
+#include "canvas/poly_item.h"
+#include "canvas/fill.h"
+
+/* similar to a Curve, with the first point being a height definition rather than a point to
+   interpolate.
+*/
+
+namespace ArdourCanvas {
+
+class LIBCANVAS_API FramedCurve : public PolyItem, public InterpolatedCurve
+{
+  public:
+    FramedCurve (Canvas*);
+    FramedCurve (Item*);
+
+    enum CurveFill {
+           None,
+           Inside,
+           Outside,
+    };
+
+    void compute_bounding_box () const;
+    void render (Rect const & area, Cairo::RefPtr<Cairo::Context>) const;
+    void set (Points const &);
+
+    void set_points_per_segment (uint32_t n);
+
+    bool covers (Duple const &) const;
+    void set_fill_mode (CurveFill cf) { curve_fill = cf; }
+
+  private:
+    Points samples;
+    Points::size_type n_samples;
+    uint32_t points_per_segment;
+    CurveFill curve_fill;
+
+    void interpolate ();
+};
+
+}
+
+#endif
diff --git a/libs/canvas/framed_curve.cc b/libs/canvas/framed_curve.cc
new file mode 100644 (file)
index 0000000..e5dfb54
--- /dev/null
@@ -0,0 +1,268 @@
+/*
+    Copyright (C) 2013 Paul Davis
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#include <cmath>
+#include <exception>
+#include <algorithm>
+
+#include "canvas/framed_curve.h"
+
+using namespace ArdourCanvas;
+using std::min;
+using std::max;
+
+FramedCurve::FramedCurve (Canvas* c)
+       : PolyItem (c)
+       , n_samples (0)
+       , points_per_segment (16)
+       , curve_fill (None)
+{
+}
+
+FramedCurve::FramedCurve (Item* parent)
+       : PolyItem (parent)
+       , n_samples (0)
+       , points_per_segment (16)
+       , curve_fill (None)
+{
+}
+
+/** When rendering the curve, we will always draw a fixed number of straight
+ * line segments to span the x-axis extent of the curve. More segments:
+ * smoother visual rendering. Less rendering: closer to a visibily poly-line
+ * render.
+ */
+void
+FramedCurve::set_points_per_segment (uint32_t n)
+{
+       /* this only changes our appearance rather than the bounding box, so we
+          just need to schedule a redraw rather than notify the parent of any
+          changes
+       */
+       points_per_segment = n;
+       interpolate ();
+       redraw ();
+}
+
+void
+FramedCurve::compute_bounding_box () const
+{
+       PolyItem::compute_bounding_box ();
+
+       /* possibly add extents of any point indicators here if we ever do that */
+}
+
+void
+FramedCurve::set (Points const& p)
+{
+       PolyItem::set (p);
+       interpolate ();
+}
+
+void
+FramedCurve::interpolate ()
+{
+       Points curve_points = _points;
+
+       if (curve_points.size()) {
+               curve_points.erase (curve_points.begin());
+       }
+       samples.clear ();
+
+       InterpolatedCurve::interpolate (curve_points, points_per_segment, CatmullRomCentripetal, false, samples);
+       n_samples = samples.size();
+}
+
+void
+FramedCurve::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
+{
+       if (!_outline || _points.size() < 3 || !_bounding_box) {
+               return;
+       }
+
+       Rect self = item_to_window (_bounding_box.get());
+       boost::optional<Rect> d = self.intersection (area);
+       assert (d);
+       Rect draw = d.get ();
+
+       /* Our approach is to always draw n_segments across our total size.
+        *
+        * This is very inefficient if we are asked to only draw a small
+        * section of the curve. For now we rely on cairo clipping to help
+        * with this.
+        */
+
+
+       setup_outline_context (context);
+
+       if (_points.size() == 3) {
+
+               /* straight line */
+
+               Duple window_space;
+               Points::const_iterator it = _points.begin();
+               window_space = item_to_window (*it);
+               context->move_to (window_space.x, window_space.y);
+               ++it;
+               window_space = item_to_window (*it);
+               context->line_to (window_space.x, window_space.y);
+               window_space = item_to_window (_points.back());
+               context->line_to (window_space.x, window_space.y);
+
+               switch (curve_fill) {
+                       case None:
+                               context->stroke();
+                               break;
+                       case Inside:
+                               context->stroke_preserve ();
+                               window_space = item_to_window (Duple(_points.back().x, draw.height()));
+                               context->line_to (window_space.x, window_space.y);
+                               window_space = item_to_window (Duple(_points.back().x, draw.height()));
+                               context->line_to (window_space.x, window_space.y);
+                               context->close_path();
+                               setup_fill_context(context);
+                               context->fill ();
+                               break;
+                       case Outside:
+                               context->stroke_preserve ();
+                               window_space = item_to_window (Duple(_points.back().x, 0.0));
+                               context->line_to (window_space.x, window_space.y);
+                               window_space = item_to_window (Duple(_points.front().x, 0.0));
+                               context->line_to (window_space.x, window_space.y);
+                               context->close_path();
+                               setup_fill_context(context);
+                               context->fill ();
+                               break;
+               }
+
+       } else {
+
+               /* curve of at least 3 points */
+
+               /* x-axis limits of the curve, in window space coordinates */
+
+               Duple w1 = item_to_window (Duple (_points.front().x, 0.0));
+               Duple w2 = item_to_window (Duple (_points.back().x, 0.0));
+
+               /* clamp actual draw to area bound by points, rather than our bounding box which is slightly different */
+
+               context->save ();
+               context->rectangle (draw.x0, draw.y0, draw.width(), draw.height());
+               context->clip ();
+
+               /* expand drawing area by several pixels on each side to avoid cairo stroking effects at the boundary.
+                  they will still occur, but cairo's clipping will hide them.
+                */
+
+               draw = draw.expand (4.0);
+
+               /* now clip it to the actual points in the curve */
+
+               if (draw.x0 < w1.x) {
+                       draw.x0 = w1.x;
+               }
+
+               if (draw.x1 >= w2.x) {
+                       draw.x1 = w2.x;
+               }
+
+               /* find left and right-most sample */
+               Duple window_space;
+               Points::size_type left = 0;
+               Points::size_type right = n_samples;
+
+               for (Points::size_type idx = 0; idx < n_samples - 1; ++idx) {
+                       left = idx;
+                       window_space = item_to_window (Duple (samples[idx].x, 0.0));
+                       if (window_space.x >= draw.x0) break;
+               }
+               for (Points::size_type idx = n_samples; idx > left + 1; --idx) {
+                       window_space = item_to_window (Duple (samples[idx].x, 0.0));
+                       if (window_space.x <= draw.x1) break;
+                       right = idx;
+               }
+
+               /* draw line between samples */
+               window_space = item_to_window (Duple (samples[left].x, samples[left].y));
+               context->move_to (window_space.x, window_space.y);
+               for (uint32_t idx = left + 1; idx < right; ++idx) {
+                       window_space = item_to_window (Duple (samples[idx].x, samples[idx].y), false);
+                       context->line_to (window_space.x, window_space.y);
+               }
+
+               switch (curve_fill) {
+                       case None:
+                               context->stroke();
+                               break;
+                       case Inside:
+                               context->stroke_preserve ();
+                               window_space = item_to_window (Duple (samples[right-1].x, draw.height()));
+                               context->line_to (window_space.x, window_space.y);
+                               window_space = item_to_window (Duple (samples[left].x, draw.height()));
+                               context->line_to (window_space.x, window_space.y);
+                               context->close_path();
+                               setup_fill_context(context);
+                               context->fill ();
+                               break;
+                       case Outside:
+                               context->stroke_preserve ();
+                               window_space = item_to_window (Duple (samples[right-1].x, 0.0));
+                               context->line_to (window_space.x, window_space.y);
+                               window_space = item_to_window (Duple (samples[left].x, 0.0));
+                               context->line_to (window_space.x, window_space.y);
+                               context->close_path();
+                               setup_fill_context(context);
+                               context->fill ();
+                               break;
+               }
+               context->restore ();
+       }
+
+#if 0
+       /* add points */
+       setup_outline_context (context);
+       for (Points::const_iterator p = _points.begin(); p != _points.end(); ++p) {
+               Duple window_space (item_to_window (*p));
+               context->arc (window_space.x, window_space.y, 5.0, 0.0, 2 * M_PI);
+               context->stroke ();
+       }
+#endif
+}
+
+bool
+FramedCurve::covers (Duple const & pc) const
+{
+       Duple point = window_to_item (pc);
+
+       /* O(N) N = number of points, and not accurate */
+
+       for (Points::const_iterator p = _points.begin(); p != _points.end(); ++p) {
+
+               const Coord dx = point.x - (*p).x;
+               const Coord dy = point.y - (*p).y;
+               const Coord dx2 = dx * dx;
+               const Coord dy2 = dy * dy;
+
+               if ((dx2 < 2.0 && dy2 < 2.0) || (dx2 + dy2 < 4.0)) {
+                       return true;
+               }
+       }
+
+       return false;
+}
index 63bccec1660baef98e09b0b874267ef006c207fc..b40f72412dbee5cbcc6779215ce62cc32314594e 100644 (file)
@@ -40,6 +40,7 @@ canvas_sources = [
         'item.cc',
         'fill.cc',
         'flag.cc',
+        'framed_curve.cc',
         'image.cc',
         'line.cc',
         'line_set.cc',