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#define __LINE_GEOMETRY_C__
/*
* Routines for dealing with lines (intersections, etc.)
*
* Authors:
* Maximilian Albert <Anhalter42@gmx.de>
*
* Copyright (C) 2007 authors
*
* Released under GNU GPL, read the file 'COPYING' for more information
*/
#include "line-geometry.h"
#include "inkscape.h"
#include "desktop-style.h"
#include "desktop-handles.h"
#include "display/sp-canvas.h"
#include "display/sodipodi-ctrl.h"
//#include "display/curve.cpp"
namespace Box3D {
/**
* Draw a line beginning at 'start'. If is_endpoint is true, use 'vec' as the endpoint
* of the segment. Otherwise interpret it as the direction of the line.
* FIXME: Think of a better way to distinguish between the two constructors of lines.
*/
Line::Line(NR::Point const &start, NR::Point const &vec, bool is_endpoint) {
pt = start;
if (is_endpoint)
v_dir = vec - start;
else
v_dir = vec;
normal = v_dir.ccw();
d0 = NR::dot(normal, pt);
}
Line::Line(Line const &line) {
pt = line.pt;
v_dir = line.v_dir;
normal = line.normal;
d0 = line.d0;
}
Line &Line::operator=(Line const &line) {
pt = line.pt;
v_dir = line.v_dir;
normal = line.normal;
d0 = line.d0;
return *this;
}
NR::Maybe<NR::Point> Line::intersect(Line const &line) {
NR::Coord denom = NR::dot(v_dir, line.normal);
g_return_val_if_fail(fabs(denom) > 1e-6, NR::Nothing());
NR::Coord lambda = (line.d0 - NR::dot(pt, line.normal)) / denom;
return pt + lambda * v_dir;
}
void Line::set_direction(NR::Point const &dir)
{
v_dir = dir;
normal = v_dir.ccw();
d0 = NR::dot(normal, pt);
}
NR::Point Line::closest_to(NR::Point const &pt)
{
/* return the intersection of this line with a perpendicular line passing through pt */
NR::Maybe<NR::Point> result = this->intersect(Line(pt, (this->v_dir).ccw(), false));
g_return_val_if_fail (result, NR::Point (0.0, 0.0));
return *result;
}
void create_canvas_point(NR::Point const &pos, double size, guint32 rgba)
{
SPDesktop *desktop = inkscape_active_desktop();
SPCanvasItem * canvas_pt = sp_canvas_item_new(sp_desktop_controls(desktop), SP_TYPE_CTRL,
"size", size,
"filled", 1,
"fill_color", rgba,
"stroked", 1,
"stroke_color", 0x000000ff,
NULL);
SP_CTRL(canvas_pt)->moveto(pos);
}
void create_canvas_line(NR::Point const &p1, NR::Point const &p2, guint32 rgba)
{
SPDesktop *desktop = inkscape_active_desktop();
SPCanvasItem *line = sp_canvas_item_new(sp_desktop_controls(desktop),
SP_TYPE_CTRLLINE, NULL);
sp_ctrlline_set_coords(SP_CTRLLINE(line), p1, p2);
sp_ctrlline_set_rgba32 (SP_CTRLLINE(line), rgba);
sp_canvas_item_show (line);
}
} // namespace Box3D
/*
Local Variables:
mode:c++
c-file-style:"stroustrup"
c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
indent-tabs-mode:nil
fill-column:99
End:
*/
// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :
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