Draw beat lines.

Region.C

@@ -36,6 +36,8 @@ using namespace std;
 
 extern Timeline timeline;
 
+Fl_Boxtype Region::_box = FL_PLASTIC_UP_BOX;
+
 void
 Region::init ( void )
 {
@@ -296,6 +298,7 @@ Region::resize ( void )
 //        Fl_Widget::resize( X, y(), W, h() );
 }
 
+int measure = 40;
 
 /* X is the timeline offset, W is the width of the track */
 void
@@ -304,6 +307,8 @@ Region::draw ( int X, int Y, int W, int H )
     if ( ! ( W > 0 && H > 0 ) )
         return;
 
+
+
     if ( _offset > timeline.xoffset + timeline.x_to_ts( _track->w() ) ||
          (  _offset < timeline.xoffset &&
             _offset + (_end - _start) < timeline.xoffset ) )
@@ -331,12 +336,15 @@ Region::draw ( int X, int Y, int W, int H )
     fl_push_clip( rx, Y, rw, H );
 
     /* dirty hack to keep the box from flipping to vertical at small sizes */
-    fl_draw_box( FL_PLASTIC_UP_BOX, rx - 10, Y, rw + 50, H, _box_color );
+    fl_draw_box( box(), rx - 10, Y, rw + 50, H, _box_color );
+
 
 //    fl_push_clip( x() + Fl::box_dx( box() ), y(), w() - Fl::box_dw( box() ), h() );
 
     draw_waveform( rx, Y, rw, H, _clip, _start + offset, min( (_end - _start) - offset, _end), _scale, _color );
 
+    timeline.draw_measure_lines( rx, Y, rw, H, _box_color );
+
     fl_color( FL_BLACK );
     fl_line( rx, Y, rx, Y + H );
     fl_line( rx + rw - 1, Y, rx + rw - 1, Y + H );
@@ -346,10 +354,10 @@ Region::draw ( int X, int Y, int W, int H )
     fl_font( FL_HELVETICA, 14 );
     fl_color( FL_BLACK );
 
-    int bx = Fl::box_dx( FL_PLASTIC_UP_BOX );
+    int bx = Fl::box_dx( box() );
-    int by = Fl::box_dy( FL_PLASTIC_UP_BOX );
+    int by = Fl::box_dy( box() );
-    int bw = Fl::box_dw( FL_PLASTIC_UP_BOX );
+    int bw = Fl::box_dw( box() );
-    int bh = Fl::box_dh( FL_PLASTIC_UP_BOX );
+    int bh = Fl::box_dh( box() );
 
     int dx = min( 32767, timeline.ts_to_x( offset ) );
 
@@ -363,8 +371,8 @@ Region::draw ( int X, int Y, int W, int H )
 //(Fl_Align)FL_ALIGN_LEFT | FL_ALIGN_BOTTOM );
 
 
-    fl_color( FL_RED );
+/*     fl_color( FL_RED ); */
-    fl_line( x(), y(), x(), y() + h() );
+/*     fl_line( x(), y(), x(), y() + h() ); */
 
 
 }

Region.H

@@ -87,9 +87,11 @@ class Region : public TrackWidget
 
     float _scale;                                               /* amplitude adjustment */
 
+    static Fl_Boxtype _box;
     static Fl_Color _selection_color;
     static Fl_Color selection_color ( void ) { return _selection_color; }
     static void selection_color ( Fl_Color v ) { _selection_color = v; }
+    static Fl_Boxtype box ( void ) { return _box; }
 
     enum trim_e { NO, LEFT, RIGHT };
     void trim ( enum trim_e t, int X );

Timeline.H

@@ -28,6 +28,8 @@
 
 #include <assert.h>
 
+#include <FL/fl_draw.H>
+
 struct Timeline {
     Fl_Scroll *scroll;
     Fl_Pack *tracks;
@@ -40,6 +42,9 @@ struct Timeline {
 
     nframes_t xoffset;
 
+    int _beats_per_bar;
+    float _beats_per_minute;
+
     int
     ts_to_x( nframes_t ts )
         {
@@ -52,6 +57,31 @@ struct Timeline {
         {
             return x * fpp;
         }
+
+
+    float
+    beats_per_minute ( void ) const
+        {
+            // TODO: this should check a tempo map.
+            return _beats_per_minute;
+        }
+
+    /* draw appropriate measure lines inside the given bounding box */
+    void
+    draw_measure_lines ( int X, int Y, int W, int H, Fl_Color color )
+        {
+            fl_line_style( FL_DASH, 2 );
+            fl_color( fl_color_average( FL_BLACK, color, 0.65f ) );
+
+            int measure = ts_to_x( sample_rate * 60 / beats_per_minute() );
+
+            for ( int x = X; x < X + W; ++x )
+
+                if ( 0 == (ts_to_x( xoffset ) + x) % measure )
+                    fl_line( x, Y, x, Y + H );
+
+            fl_line_style( FL_SOLID, 0 );
+        }
 };
 
 extern Timeline timeline;

Track.C

@@ -29,6 +29,8 @@ Track::draw ( void )
 {
     Fl_Group::draw();
 
+    timeline.draw_measure_lines( x(), y(), w(), h(), color() );
+
     fl_push_clip( x(), y(), w(), h() );
 
     for ( list <Region *>::iterator r = _regions.begin();  r != _regions.end(); r++ )

main.C

@@ -113,7 +113,7 @@ main ( int argc, char **argv )
     timeline.scroll = new Fl_Scroll( 0, 24, 800, 600 - (24 * 2) );
     timeline.scroll->type( Fl_Scroll::VERTICAL );
     timeline.fpp = 256;
-
+    timeline._beats_per_minute = 120;
 
     timeline.sample_rate = 44100;