ardour/gtk2_ardour/tempo_lines.cc

187 lines
5.3 KiB
C++

/*
Copyright (C) 2002-2007 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 "pbd/compose.h"
#include "canvas/canvas.h"
#include "canvas/debug.h"
#include "tempo_lines.h"
#include "public_editor.h"
#include "rgb_macros.h"
#include "ui_config.h"
using namespace std;
TempoLines::TempoLines (ArdourCanvas::Container* group, double, ARDOUR::BeatsSamplesConverter* bfc)
: lines (group, ArdourCanvas::LineSet::Vertical)
, _bfc (bfc)
{
lines.set_extent (ArdourCanvas::COORD_MAX);
}
TempoLines::~TempoLines ()
{
delete _bfc;
_bfc = 0;
}
void
TempoLines::tempo_map_changed (samplepos_t new_origin)
{
lines.clear ();
_bfc->set_origin_b (new_origin);
}
void
TempoLines::show ()
{
lines.show ();
}
void
TempoLines::hide ()
{
lines.hide ();
}
void
TempoLines::draw_ticks (std::vector<ARDOUR::TempoMap::BBTPoint>& grid,
unsigned divisions,
samplecnt_t leftmost_sample,
samplecnt_t sample_rate)
{
const uint32_t base = UIConfiguration::instance().color_mod("measure line beat", "measure line beat");
for (unsigned l = 1; l < divisions; ++l) {
/* find the coarsest division level this tick falls on */
unsigned level = divisions;
for (unsigned d = divisions; d >= 4; d /= 2) {
if (l % (divisions / d) == 0) {
level = d;
}
}
/* draw line with alpha corresponding to coarsest level */
const uint8_t a = max(8, (int)rint(UINT_RGBA_A(base) / (0.8 * log2(level))));
const uint32_t c = UINT_RGBA_CHANGE_A(base, a);
const samplepos_t f = _bfc->to (Temporal::Beats (grid.begin()->qn + (l / (double) divisions))) + _bfc->origin_b();
if (f > leftmost_sample) {
lines.add (PublicEditor::instance().sample_to_pixel_unrounded (f), 1.0, c);
}
}
}
void
TempoLines::draw (std::vector<ARDOUR::TempoMap::BBTPoint>& grid,
unsigned divisions,
samplecnt_t leftmost_sample,
samplecnt_t sample_rate)
{
std::vector<ARDOUR::TempoMap::BBTPoint>::const_iterator i;
double beat_density;
uint32_t beats = 0;
uint32_t bars = 0;
const uint32_t bar_color = UIConfiguration::instance().color ("measure line bar");
const uint32_t beat_color = UIConfiguration::instance().color_mod ("measure line beat", "measure line beat");
uint32_t color;
bool all_bars = false;
/* get the first bar spacing */
i = grid.end();
i--;
bars = (*i).bar - (*grid.begin()).bar;
int32_t bar_mod = 4;
if (bars < distance (grid.begin(), grid.end()) - 1) {
/* grid contains beats and bars */
beats = distance (grid.begin(), grid.end()) - bars;
} else {
/* grid contains only bars */
beats = distance (grid.begin(), grid.end());
if (i != grid.begin()) {
const int32_t last_bar = (*i).bar;
i--;
bar_mod = (last_bar - (*i).bar) * 4;
}
all_bars = true;
}
double canvas_width_used = 1.0;
if (leftmost_sample < grid.front().sample) {
const samplecnt_t sample_distance = max ((samplecnt_t) 1, grid.back().sample - grid.front().sample);
canvas_width_used = 1.0 - ((grid.front().sample - leftmost_sample) / (double) (sample_distance + grid.front().sample));
}
beat_density = (beats * 10.0f) / (lines.canvas()->width() * canvas_width_used);
if (beat_density > 2.0f) {
/* if the lines are too close together, they become useless */
lines.clear ();
return;
}
/* constrain divisions to a log2 factor to cap line density */
while (divisions > 3 && beat_density * divisions > 0.4) {
divisions /= 2;
}
lines.clear ();
if (beat_density <= 0.12 && grid.begin() != grid.end() && grid.begin()->sample > 0 && !all_bars) {
/* draw subdivisions of the beat before the first visible beat line XX this shouldn't happen now */
std::vector<ARDOUR::TempoMap::BBTPoint> vec;
vec.push_back (*i);
draw_ticks (vec, divisions, leftmost_sample, sample_rate);
}
for (i = grid.begin(); i != grid.end(); ++i) {
if ((*i).is_bar()) {
/* keep all_bar beat density down */
if (all_bars && beat_density > 0.3 && ((*i).bar % bar_mod) != 1) {
continue;
}
color = bar_color;
} else {
if (beat_density > 0.3) {
continue; /* only draw beat lines if the gaps between beats are large. */
}
color = beat_color;
}
ArdourCanvas::Coord xpos = PublicEditor::instance().sample_to_pixel_unrounded ((*i).sample);
lines.add (xpos, 1.0, color);
if (beat_density <= 0.12 && !all_bars) {
/* draw subdivisions of this beat */
std::vector<ARDOUR::TempoMap::BBTPoint> vec;
vec.push_back (*i);
draw_ticks (vec, divisions, leftmost_sample, sample_rate);
}
}
}