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livetrax/libs/widgets/ardour_knob.cc

395 lines
12 KiB
C++

/*
* Copyright (C) 2010 Paul Davis <paul@linuxaudiosystems.com>
* Copyright (C) 2017-2021 Robin Gareus <robin@gareus.org>
*
* 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <algorithm>
#include <pangomm/layout.h>
#include "pbd/compose.h"
#include "gtkmm2ext/rgb_macros.h"
#include "gtkmm2ext/utils.h"
#include "widgets/ardour_knob.h"
#include "widgets/ui_config.h"
#include "pbd/i18n.h"
using namespace ArdourWidgets;
using namespace PBD;
ArdourKnob::Element ArdourKnob::default_elements = ArdourKnob::Element (ArdourKnob::Arc);
ArdourKnob::ArdourKnob (Element e, Flags flags)
: ArdourCtrlBase (flags)
, _elements (e)
, _extra_height (0)
{
}
void
ArdourKnob::gen_faceplate (Pango::FontDescription const& font,
std::string const& lbl_left,
std::string const& lbl_right,
std::string const& caption)
{
_bg.clear ();
if (lbl_left.empty () && lbl_right.empty () && caption.empty ()) {
_extra_height = 0;
queue_resize ();
return;
}
Gtk::Requisition req;
on_size_request (&req);
Glib::RefPtr<Pango::Layout> layout = Pango::Layout::create (get_pango_context ());
layout->set_font_description (font);
int extra_width = 0;
int extra_height = 0;
int lbl_pos = req.width * .2; // ~65 deg
int lbl_max = req.width * .4;
int lbl_left_x = req.width * .2;
int lbl_right_x = req.width * .8;
int lbl_lr_y = req.height * .9;
if (!lbl_left.empty ()) {
int w, h;
layout->set_text (lbl_left);
layout->get_pixel_size (w, h);
extra_height = std::max (extra_height, h - req.height / 4);
if (2 * w > lbl_max) {
/* label is too long to center */
extra_width = std::max (extra_width, w - lbl_max);
// TODO set lbl_left_x, right-align text
} else {
extra_width = std::max (extra_width, w / 2 - lbl_pos);
}
}
if (!lbl_right.empty ()) {
int w, h;
layout->set_text (lbl_right);
layout->get_pixel_size (w, h);
extra_height = std::max (extra_height, h - 1);
if (2 * w > lbl_max) {
/* label is too long to center */
extra_width = std::max (extra_width, w - lbl_max);
//TODO set lbl_right_x, left-align text
} else {
extra_width = std::max (extra_width, w / 2 - lbl_pos);
}
}
if (!caption.empty ()) {
int w, h;
layout->set_text (caption);
layout->get_pixel_size (w, h);
extra_height += h;
extra_width = std::max (extra_width, w - req.width);
}
req.width += extra_width;
req.height += extra_height;
_bg = Cairo::ImageSurface::create (Cairo::FORMAT_ARGB32, req.width, req.height);
Cairo::RefPtr<Cairo::Context> cr = Cairo::Context::create (_bg);
Gtkmm2ext::Color txt_color = UIConfigurationBase::instance ().color ("gtk_foreground");
Gtkmm2ext::set_source_rgba (cr, txt_color);
if (!lbl_left.empty ()) {
int w, h;
layout->set_text (lbl_left);
layout->get_pixel_size (w, h);
cr->move_to (lbl_left_x - w * .5, lbl_lr_y);
layout->show_in_cairo_context (cr);
}
if (!lbl_right.empty ()) {
int w, h;
layout->set_text (lbl_right);
layout->get_pixel_size (w, h);
cr->move_to (lbl_right_x - w * .5, lbl_lr_y);
layout->show_in_cairo_context (cr);
}
if (!caption.empty ()) {
int w, h;
layout->set_text (caption);
layout->get_pixel_size (w, h);
cr->move_to ((req.width - w) * .5, req.height - h - 2);
layout->show_in_cairo_context (cr);
}
_extra_height = extra_height;
_bg->flush ();
queue_resize ();
}
void
ArdourKnob::render (Cairo::RefPtr<Cairo::Context> const& ctx, cairo_rectangle_t*)
{
cairo_t* cr = ctx->cobj ();
float width = get_width ();
float height = get_height ();
if (_bg) {
cairo_set_source_surface (cr, _bg->cobj (), 0, 0);
cairo_set_operator (cr, CAIRO_OPERATOR_OVER);
cairo_paint (cr);
height -= _extra_height;
}
const float scale = std::min (width, height);
const float pointer_thickness = 3.0 * (scale / 80); // if the knob is 80 pixels wide, we want a 3-pix line on it
const float start_angle = ((180 - 65) * G_PI) / 180;
const float end_angle = ((360 + 65) * G_PI) / 180;
float zero = 0;
if (_flags & ArcToZero) {
zero = _normal;
}
const float value_angle = start_angle + (_val * (end_angle - start_angle));
const float zero_angle = start_angle + (zero * (end_angle - start_angle));
float value_x = cos (value_angle);
float value_y = sin (value_angle);
float xc = 0.5 + width / 2.0;
float yc = 0.5 + height / 2.0;
cairo_translate (cr, xc, yc);
/* get the knob color from the theme */
Gtkmm2ext::Color knob_color = UIConfigurationBase::instance ().color (string_compose ("%1", get_name ()));
float center_radius = 0.48 * scale;
float border_width = 0.8;
bool arc = (_elements & Arc) == Arc;
bool bevel = (_elements & Bevel) == Bevel;
bool flat = flat_buttons ();
if (arc) {
center_radius = scale * 0.33;
float inner_progress_radius = scale * 0.38;
float outer_progress_radius = scale * 0.48;
float progress_width = (outer_progress_radius - inner_progress_radius);
float progress_radius = inner_progress_radius + progress_width / 2.0;
/* dark arc background */
cairo_set_source_rgb (cr, 0.3, 0.3, 0.3);
cairo_set_line_width (cr, progress_width);
cairo_arc (cr, 0, 0, progress_radius, start_angle, end_angle);
cairo_stroke (cr);
/* look up the arc colors from the config */
double red_start, green_start, blue_start, unused;
double red_end, green_end, blue_end;
Gtkmm2ext::Color arc_start_color = UIConfigurationBase::instance ().color (string_compose ("%1: arc start", get_name ()));
Gtkmm2ext::color_to_rgba (arc_start_color, red_start, green_start, blue_start, unused);
Gtkmm2ext::Color arc_end_color = UIConfigurationBase::instance ().color (string_compose ("%1: arc end", get_name ()));
Gtkmm2ext::color_to_rgba (arc_end_color, red_end, green_end, blue_end, unused);
/* vary the arc color over the travel of the knob */
float intensity = fabsf (_val - zero) / std::max (zero, (1.f - zero));
const float intensity_inv = 1.0 - intensity;
float r = intensity_inv * red_end + intensity * red_start;
float g = intensity_inv * green_end + intensity * green_start;
float b = intensity_inv * blue_end + intensity * blue_start;
/* draw the arc */
cairo_set_source_rgb (cr, r, g, b);
cairo_set_line_width (cr, progress_width);
if (zero_angle > value_angle) {
cairo_arc (cr, 0, 0, progress_radius, value_angle, zero_angle);
} else {
cairo_arc (cr, 0, 0, progress_radius, zero_angle, value_angle);
}
cairo_stroke (cr);
/* shade the arc */
if (!flat) {
cairo_pattern_t* shade_pattern;
shade_pattern = cairo_pattern_create_linear (0.0, -yc, 0.0, yc);
cairo_pattern_add_color_stop_rgba (shade_pattern, 0.0, 1, 1, 1, 0.15);
cairo_pattern_add_color_stop_rgba (shade_pattern, 0.5, 1, 1, 1, 0.0);
cairo_pattern_add_color_stop_rgba (shade_pattern, 1.0, 1, 1, 1, 0.0);
cairo_set_source (cr, shade_pattern);
cairo_arc (cr, 0, 0, outer_progress_radius - 1, 0, 2.0 * G_PI);
cairo_fill (cr);
cairo_pattern_destroy (shade_pattern);
}
#if 0 //black border
const float start_angle_x = cos (start_angle);
const float start_angle_y = sin (start_angle);
const float end_angle_x = cos (end_angle);
const float end_angle_y = sin (end_angle);
cairo_set_source_rgb (cr, 0, 0, 0 );
cairo_set_line_width (cr, border_width);
cairo_move_to (cr, (outer_progress_radius * start_angle_x), (outer_progress_radius * start_angle_y));
cairo_line_to (cr, (inner_progress_radius * start_angle_x), (inner_progress_radius * start_angle_y));
cairo_stroke (cr);
cairo_move_to (cr, (outer_progress_radius * end_angle_x), (outer_progress_radius * end_angle_y));
cairo_line_to (cr, (inner_progress_radius * end_angle_x), (inner_progress_radius * end_angle_y));
cairo_stroke (cr);
cairo_arc (cr, 0, 0, outer_progress_radius, start_angle, end_angle);
cairo_stroke (cr);
#endif
}
if (!flat) {
/* knob shadow */
cairo_save (cr);
cairo_translate (cr, pointer_thickness + 1, pointer_thickness + 1);
cairo_set_source_rgba (cr, 0, 0, 0, 0.1);
cairo_arc (cr, 0, 0, center_radius - 1, 0, 2.0 * G_PI);
cairo_fill (cr);
cairo_restore (cr);
/* inner circle */
Gtkmm2ext::set_source_rgba (cr, knob_color);
cairo_arc (cr, 0, 0, center_radius, 0, 2.0 * G_PI);
cairo_fill (cr);
if (bevel) {
/* knob gradient */
cairo_pattern_t* shade_pattern;
shade_pattern = cairo_pattern_create_linear (0.0, -yc, 0.0, yc);
cairo_pattern_add_color_stop_rgba (shade_pattern, 0.0, 1, 1, 1, 0.2);
cairo_pattern_add_color_stop_rgba (shade_pattern, 0.2, 1, 1, 1, 0.2);
cairo_pattern_add_color_stop_rgba (shade_pattern, 0.8, 0, 0, 0, 0.2);
cairo_pattern_add_color_stop_rgba (shade_pattern, 1.0, 0, 0, 0, 0.2);
cairo_set_source (cr, shade_pattern);
cairo_arc (cr, 0, 0, center_radius, 0, 2.0 * G_PI);
cairo_fill (cr);
cairo_pattern_destroy (shade_pattern);
/* flat top over beveled edge */
Gtkmm2ext::set_source_rgb_a (cr, knob_color, 0.5);
cairo_arc (cr, 0, 0, center_radius - pointer_thickness, 0, 2.0 * G_PI);
cairo_fill (cr);
} else {
/* radial gradient */
cairo_pattern_t* shade_pattern;
shade_pattern = cairo_pattern_create_radial (-center_radius, -center_radius, 1, -center_radius, -center_radius, center_radius * 2.5);
cairo_pattern_add_color_stop_rgba (shade_pattern, 0.0, 1, 1, 1, 0.2);
cairo_pattern_add_color_stop_rgba (shade_pattern, 1.0, 0, 0, 0, 0.3);
cairo_set_source (cr, shade_pattern);
cairo_arc (cr, 0, 0, center_radius, 0, 2.0 * G_PI);
cairo_fill (cr);
cairo_pattern_destroy (shade_pattern);
}
} else {
/* inner circle */
Gtkmm2ext::set_source_rgba (cr, knob_color);
cairo_arc (cr, 0, 0, center_radius, 0, 2.0 * G_PI);
cairo_fill (cr);
}
/* black knob border */
cairo_set_line_width (cr, border_width);
cairo_set_source_rgba (cr, 0, 0, 0, 1);
cairo_arc (cr, 0, 0, center_radius, 0, 2.0 * G_PI);
cairo_stroke (cr);
/* line shadow */
if (!flat) {
cairo_save (cr);
cairo_translate (cr, 1, 1);
cairo_set_source_rgba (cr, 0, 0, 0, 0.3);
cairo_set_line_cap (cr, CAIRO_LINE_CAP_ROUND);
cairo_set_line_width (cr, pointer_thickness);
cairo_move_to (cr, (center_radius * value_x), (center_radius * value_y));
cairo_line_to (cr, ((center_radius * 0.4) * value_x), ((center_radius * 0.4) * value_y));
cairo_stroke (cr);
cairo_restore (cr);
}
/* line */
cairo_set_source_rgba (cr, 1, 1, 1, 1);
cairo_set_line_cap (cr, CAIRO_LINE_CAP_ROUND);
cairo_set_line_width (cr, pointer_thickness);
cairo_move_to (cr, (center_radius * value_x), (center_radius * value_y));
cairo_line_to (cr, ((center_radius * 0.4) * value_x), ((center_radius * 0.4) * value_y));
cairo_stroke (cr);
/* a transparent overlay to indicate insensitivity */
if (!get_sensitive ()) {
cairo_arc (cr, 0, 0, center_radius, 0, 2.0 * G_PI);
uint32_t ins_color = UIConfigurationBase::instance ().color ("gtk_background");
Gtkmm2ext::set_source_rgb_a (cr, ins_color, 0.6);
cairo_fill (cr);
}
/* highlight if grabbed or if mouse is hovering over me */
if (_tooltip.dragging () || (_hovering && UIConfigurationBase::instance ().get_widget_prelight ())) {
cairo_set_source_rgba (cr, 1, 1, 1, 0.12);
cairo_arc (cr, 0, 0, center_radius, 0, 2.0 * G_PI);
cairo_fill (cr);
}
cairo_identity_matrix (cr);
}
void
ArdourKnob::on_size_request (Gtk::Requisition* req)
{
req->width = _req_width;
req->height = _req_height;
if (req->width < 1) {
req->width = 13;
}
if (req->height < 1) {
req->height = 13;
}
/* knob is square */
req->width = std::max (req->width, req->height);
req->height = std::max (req->width, req->height);
if (_bg) {
req->width = std::max (req->width, _bg->get_width ());
req->height = std::max (req->height, _bg->get_height ());
}
}
void
ArdourKnob::set_elements (Element e)
{
_elements = e;
}
void
ArdourKnob::add_elements (Element e)
{
_elements = (ArdourKnob::Element) (_elements | e);
}