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diff --git a/src/line-geometry.cpp b/src/line-geometry.cpp
index 549defb2ed71f335c1832dfb85aa713e970d86e8..2e528f3afe5b555e64c459f02ef58e5d76a16836 100644 (file)
--- a/src/line-geometry.cpp
+++ b/src/line-geometry.cpp
#include "line-geometry.h"
#include "inkscape.h"
+#include "desktop.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 {
* 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) {
+Line::Line(Geom::Point const &start, Geom::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);
+ d0 = Geom::dot(normal, pt);
}
Line::Line(Line const &line) {
return *this;
}
-NR::Maybe<NR::Point> Line::intersect(Line const &line) {
- NR::Coord denom = NR::dot(v_dir, line.normal);
- NR::Maybe<NR::Point> no_point = NR::Nothing();
- g_return_val_if_fail(fabs(denom) > 1e-6, no_point );
+boost::optional<Geom::Point> Line::intersect(Line const &line) {
+ Geom::Coord denom = Geom::dot(v_dir, line.normal);
+ boost::optional<Geom::Point> no_point;
+ if (fabs(denom) < 1e-6)
+ return no_point;
- NR::Coord lambda = (line.d0 - NR::dot(pt, line.normal)) / denom;
+ Geom::Coord lambda = (line.d0 - Geom::dot(pt, line.normal)) / denom;
return pt + lambda * v_dir;
}
-void Line::set_direction(NR::Point const &dir)
+void Line::set_direction(Geom::Point const &dir)
{
v_dir = dir;
normal = v_dir.ccw();
- d0 = NR::dot(normal, pt);
+ d0 = Geom::dot(normal, pt);
}
-NR::Point Line::closest_to(NR::Point const &pt)
+Geom::Point Line::closest_to(Geom::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));
+ boost::optional<Geom::Point> result = this->intersect(Line(pt, (this->v_dir).ccw(), false));
+ g_return_val_if_fail (result, Geom::Point (0.0, 0.0));
return *result;
}
-double Line::lambda (NR::Point const pt)
+double Line::lambda (Geom::Point const pt)
{
- double sign = (NR::dot (pt - this->pt, this->v_dir) > 0) ? 1.0 : -1.0;
- double lambda = sign * NR::L2 (pt - this->pt);
+ double sign = (Geom::dot (pt - this->pt, this->v_dir) > 0) ? 1.0 : -1.0;
+ double lambda = sign * Geom::L2 (pt - this->pt);
// FIXME: It may speed things up (but how much?) if we assume that
// pt lies on the line and thus skip the following test
- NR::Point test = point_from_lambda (lambda);
+ Geom::Point test = point_from_lambda (lambda);
if (!pts_coincide (pt, test)) {
g_warning ("Point does not lie on line.\n");
return 0;
return lambda;
}
-inline static double determinant (NR::Point const &a, NR::Point const &b)
-{
- return (a[NR::X] * b[NR::Y] - a[NR::Y] * b[NR::X]);
-}
-
/* The coordinates of w with respect to the basis {v1, v2} */
-std::pair<double, double> coordinates (NR::Point const &v1, NR::Point const &v2, NR::Point const &w)
+std::pair<double, double> coordinates (Geom::Point const &v1, Geom::Point const &v2, Geom::Point const &w)
{
double det = determinant (v1, v2);;
if (fabs (det) < epsilon) {
@@ -110,25 +106,25 @@ std::pair<double, double> coordinates (NR::Point const &v1, NR::Point const &v2,
}
/* whether w lies inside the sector spanned by v1 and v2 */
-bool lies_in_sector (NR::Point const &v1, NR::Point const &v2, NR::Point const &w)
+bool lies_in_sector (Geom::Point const &v1, Geom::Point const &v2, Geom::Point const &w)
{
std::pair<double, double> coords = coordinates (v1, v2, w);
if (coords.first == HUGE_VAL) {
// catch the case that the vectors are not linearly independent
// FIXME: Can we assume that it's safe to return true if the vectors point in different directions?
- return (NR::dot (v1, v2) < 0);
+ return (Geom::dot (v1, v2) < 0);
}
return (coords.first >= 0 and coords.second >= 0);
}
-bool lies_in_quadrangle (NR::Point const &A, NR::Point const &B, NR::Point const &C, NR::Point const &D, NR::Point const &pt)
+bool lies_in_quadrangle (Geom::Point const &A, Geom::Point const &B, Geom::Point const &C, Geom::Point const &D, Geom::Point const &pt)
{
return (lies_in_sector (D - A, B - A, pt - A) && lies_in_sector (D - C, B - C, pt - C));
}
-static double pos_angle (NR::Point v, NR::Point w)
+static double pos_angle (Geom::Point v, Geom::Point w)
{
- return fabs (NR::atan2 (v) - NR::atan2 (w));
+ return fabs (Geom::atan2 (v) - Geom::atan2 (w));
}
/*
* starting at pt and going into direction dir.
* If none of the sides is hit, it returns a pair containing two identical points.
*/
-std::pair<NR::Point, NR::Point>
-side_of_intersection (NR::Point const &A, NR::Point const &B, NR::Point const &C, NR::Point const &D,
- NR::Point const &pt, NR::Point const &dir)
+std::pair<Geom::Point, Geom::Point>
+side_of_intersection (Geom::Point const &A, Geom::Point const &B, Geom::Point const &C, Geom::Point const &D,
+ Geom::Point const &pt, Geom::Point const &dir)
{
- NR::Point dir_A (A - pt);
- NR::Point dir_B (B - pt);
- NR::Point dir_C (C - pt);
- NR::Point dir_D (D - pt);
+ Geom::Point dir_A (A - pt);
+ Geom::Point dir_B (B - pt);
+ Geom::Point dir_C (C - pt);
+ Geom::Point dir_D (D - pt);
- std::pair<NR::Point, NR::Point> result;
+ std::pair<Geom::Point, Geom::Point> result;
double angle = -1;
double tmp_angle;
@@ -182,58 +178,24 @@ side_of_intersection (NR::Point const &A, NR::Point const &B, NR::Point const &C
}
}
-double cross_ratio (NR::Point const &A, NR::Point const &B, NR::Point const &C, NR::Point const &D)
-{
- Line line (A, D);
- double lambda_A = line.lambda (A);
- double lambda_B = line.lambda (B);
- double lambda_C = line.lambda (C);
- double lambda_D = line.lambda (D);
-
- if (fabs (lambda_D - lambda_A) < epsilon || fabs (lambda_C - lambda_B) < epsilon) {
- // FIXME: What should we return if the cross ratio can't be computed?
- return 0;
- //return NR_HUGE;
- }
- return (((lambda_C - lambda_A) / (lambda_D - lambda_A)) * ((lambda_D - lambda_B) / (lambda_C - lambda_B)));
-}
-
-double cross_ratio (VanishingPoint const &V, NR::Point const &B, NR::Point const &C, NR::Point const &D)
+boost::optional<Geom::Point> Line::intersection_with_viewbox (SPDesktop *desktop)
{
- if (V.is_finite()) {
- return cross_ratio (V.get_pos(), B, C, D);
- } else {
- Line line (B, D);
- double lambda_B = line.lambda (B);
- double lambda_C = line.lambda (C);
- double lambda_D = line.lambda (D);
-
- if (fabs (lambda_C - lambda_B) < epsilon) {
- // FIXME: What should we return if the cross ratio can't be computed?
- return 0;
- //return NR_HUGE;
- }
- return (lambda_D - lambda_B) / (lambda_C - lambda_B);
+ Geom::Rect vb = desktop->get_display_area();
+ /* remaining viewbox corners */
+ Geom::Point ul (vb.min()[Geom::X], vb.max()[Geom::Y]);
+ Geom::Point lr (vb.max()[Geom::X], vb.min()[Geom::Y]);
+
+ std::pair <Geom::Point, Geom::Point> e = side_of_intersection (vb.min(), lr, vb.max(), ul, this->pt, this->v_dir);
+ if (e.first == e.second) {
+ // perspective line lies outside the canvas
+ return boost::optional<Geom::Point>();
}
-}
-
-NR::Point fourth_pt_with_given_cross_ratio (NR::Point const &A, NR::Point const &C, NR::Point const &D, double gamma)
-{
- Line line (A, D);
- double lambda_A = line.lambda (A);
- double lambda_C = line.lambda (C);
- double lambda_D = line.lambda (D);
- double beta = (lambda_C - lambda_A) / (lambda_D - lambda_A);
- if (fabs (beta - gamma) < epsilon) {
- // FIXME: How to handle the case when the point can't be computed?
- // g_warning ("Cannot compute point with given cross ratio.\n");
- return NR::Point (0.0, 0.0);
- }
- return line.point_from_lambda ((beta * lambda_D - gamma * lambda_C) / (beta - gamma));
+ Line line (e.first, e.second);
+ return this->intersect (line);
}
-void create_canvas_point(NR::Point const &pos, double size, guint32 rgba)
+void create_canvas_point(Geom::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,
SP_CTRL(canvas_pt)->moveto(pos);
}
-void create_canvas_line(NR::Point const &p1, NR::Point const &p2, guint32 rgba)
+void create_canvas_line(Geom::Point const &p1, Geom::Point const &p2, guint32 rgba)
{
SPDesktop *desktop = inkscape_active_desktop();
SPCanvasItem *line = sp_canvas_item_new(sp_desktop_controls(desktop),
fill-column:99
End:
*/
-// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99 :
+// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :