13
0
livetrax/libs/canvas/rectangle.cc

241 lines
5.2 KiB
C++

/*
Copyright (C) 2011-2013 Paul Davis
Author: Carl Hetherington <cth@carlh.net>
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 <iostream>
#include <cairomm/context.h>
#include "pbd/stacktrace.h"
#include "pbd/compose.h"
#include "canvas/canvas.h"
#include "canvas/rectangle.h"
#include "canvas/debug.h"
#include "canvas/utils.h"
using namespace std;
using namespace ArdourCanvas;
Rectangle::Rectangle (Canvas* c)
: Item (c)
, _outline_what ((What) (LEFT | RIGHT | TOP | BOTTOM))
{
}
Rectangle::Rectangle (Canvas* c, Rect const & rect)
: Item (c)
, _rect (rect)
, _outline_what ((What) (LEFT | RIGHT | TOP | BOTTOM))
{
}
Rectangle::Rectangle (Item* parent)
: Item (parent)
, _outline_what ((What) (LEFT | RIGHT | TOP | BOTTOM))
{
}
Rectangle::Rectangle (Item* parent, Rect const & rect)
: Item (parent)
, _rect (rect)
, _outline_what ((What) (LEFT | RIGHT | TOP | BOTTOM))
{
}
void
Rectangle::render (Rect const & area, Cairo::RefPtr<Cairo::Context> context) const
{
/* In general, a Rectangle will have a _position of (0,0) within its
parent, and its extent is actually defined by _rect. But in the
unusual case that _position is set to something other than (0,0),
we should take that into account when rendering.
*/
Rect self = item_to_window (_rect.translate (_position));
boost::optional<Rect> r = self.intersection (area);
if (!r) {
return;
}
Rect draw = r.get ();
if (_fill && !_transparent) {
if (_stops.empty()) {
setup_fill_context (context);
} else {
setup_gradient_context (context, self, Duple (draw.x0, draw.y0));
}
context->rectangle (draw.x0, draw.y0, draw.width(), draw.height());
context->fill ();
}
if (_outline) {
setup_outline_context (context);
if (_outline_what == What (LEFT|RIGHT|BOTTOM|TOP)) {
context->rectangle (self.x0 + 0.5, self.y0 + 0.5, self.width() - 1.0, self.height() - 1.0);
} else {
/* the goal here is that if the border is 1 pixel
* thick, it will precisely align with the corner
* coordinates of the rectangle. So if the rectangle
* has a left edge at 0 and a right edge at 10, then
* the right edge must span -0.5..+0.5, the left edge
* must span 9.5..10.5 (i.e. the single full color
* pixel is precisely aligned with 0 and 10
* respectively).
*
* we have to shift left/up in all cases, which means
* subtraction along both axes.
*
* see the cairo FAQ on single pixel lines to see why we do
* the 0.5 pixel additions.
*/
if (_outline_what & LEFT) {
/* vertical line: move x-coordinate left by 0.5 pixels */
context->move_to (self.x0 - 0.5, self.y0);
context->line_to (self.x0 - 0.5, self.y1);
}
if (_outline_what & TOP) {
/* horizontal line: move y-coordinate up by 0.5 pixels */
context->move_to (self.x0, self.y0 - 0.5);
context->line_to (self.x1, self.y0 - 0.5);
}
if (_outline_what & BOTTOM) {
/* horizontal line: move y-coordinate up by 0.5 pixels */
context->move_to (self.x0, self.y1 - 0.5);
context->line_to (self.x1, self.y1 - 0.5);
}
if (_outline_what & RIGHT) {
/* vertical line: move x-coordinate left by 0.5 pixels */
context->move_to (self.x1 - 0.5, self.y0);
context->line_to (self.x1 - 0.5, self.y1);
}
}
context->stroke ();
}
}
void
Rectangle::compute_bounding_box () const
{
if (!_rect.empty()) {
Rect r = _rect.fix ();
/* take into acount the 0.5 addition to the bounding
box for the right and bottom edges, see ::render() above
*/
r.x1 += 1.0; // XXX this makes no sense but is necessary
r.y1 += 0.5;
_bounding_box = r;
}
_bounding_box_dirty = false;
}
void
Rectangle::set (Rect const & r)
{
/* We don't update the bounding box here; it's just
as cheap to do it when asked.
*/
if (r != _rect) {
begin_change ();
_rect = r;
_bounding_box_dirty = true;
end_change ();
}
}
void
Rectangle::set_x0 (Coord x0)
{
if (x0 != _rect.x0) {
begin_change ();
_rect.x0 = x0;
_bounding_box_dirty = true;
end_change ();
}
}
void
Rectangle::set_y0 (Coord y0)
{
if (y0 != _rect.y0) {
begin_change ();
_rect.y0 = y0;
_bounding_box_dirty = true;
end_change();
}
}
void
Rectangle::set_x1 (Coord x1)
{
if (x1 != _rect.x1) {
begin_change ();
_rect.x1 = x1;
_bounding_box_dirty = true;
end_change ();
}
}
void
Rectangle::set_y1 (Coord y1)
{
if (y1 != _rect.y1) {
begin_change ();
_rect.y1 = y1;
_bounding_box_dirty = true;
end_change ();
}
}
void
Rectangle::set_outline_what (What what)
{
if (what != _outline_what) {
begin_visual_change ();
_outline_what = what;
end_visual_change ();
}
}