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#include <2geom/d2.h>
#include <2geom/sbasis.h>
#include <2geom/sbasis-geometric.h>
#include <2geom/sbasis-2d.h>
#include <2geom/bezier-to-sbasis.h>
#include <2geom/transforms.h>
#include <2geom/sbasis-math.h>
#include <toys/path-cairo.h>
#include <toys/toy-framework-2.h>
#include <2geom/path.h>
#include <2geom/svg-path-parser.h>
#include <gsl/gsl_matrix.h>
#include <vector>
using std::vector;
using namespace Geom;
using namespace std;
class Box3d: public Toy {
double tmat[3][4];
PointHandle origin_handle;
PointSetHandle vanishing_points_handles;
PathVector paths_a;
void draw(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) override {
Geom::Point orig = origin_handle.pos;
cairo_set_source_rgba (cr, 0., 0.125, 0, 1);
/* create the transformation matrix for the map P^3 --> P^2 that has the following effect:
(1 : 0 : 0 : 0) --> vanishing point in x direction (= handle #0)
(0 : 1 : 0 : 0) --> vanishing point in y direction (= handle #1)
(0 : 0 : 1 : 0) --> vanishing point in z direction (= handle #2)
(0 : 0 : 0 : 1) --> origin (= handle #3)
*/
for (int j = 0; j < 4; ++j) {
tmat[0][j] = vanishing_points_handles.pts[j][0];
tmat[1][j] = vanishing_points_handles.pts[j][1];
tmat[2][j] = 1;
}
*notify << "Projection matrix:" << endl;
for (auto & i : tmat) {
for (double j : i) {
*notify << j << " ";
}
*notify << endl;
}
for(const auto & i : paths_a) {
Piecewise<D2<SBasis> > path_a_pw = i.toPwSb();
D2<Piecewise<SBasis> > B = make_cuts_independent(path_a_pw);
Piecewise<SBasis> preimage[4];
preimage[0] = (B[0] - orig[0]) / 100;
preimage[1] = -(B[1] - orig[1]) / 100;
Piecewise<SBasis> res[3];
for (int j = 0; j < 3; ++j) {
res[j] = preimage[0] * tmat[j][0]
+ preimage[1] * tmat[j][1]
+ tmat[j][3];
}
//if (fabs (res[2]) > 0.000001) {
D2<Piecewise<SBasis> > result(divide(res[0],res[2], 2),
divide(res[1],res[2], 2));
cairo_d2_pw_sb(cr, result);
cairo_set_source_rgba (cr, 0., 0.125, 0, 1);
cairo_stroke(cr);
}
Toy::draw(cr, notify, width, height, save,timer_stream);
}
void first_time(int argc, char** argv) override {
const char *path_a_name="ptitle.svgd";
if(argc > 1)
path_a_name = argv[1];
paths_a = read_svgd(path_a_name);
assert(paths_a.size() > 0);
// Finite images of the three vanishing points and the origin
handles.push_back(&origin_handle);
handles.push_back(&vanishing_points_handles);
vanishing_points_handles.push_back(550,350);
vanishing_points_handles.push_back(150,300);
vanishing_points_handles.push_back(380,40);
vanishing_points_handles.push_back(340,450);
// plane origin
origin_handle.pos = Point(180,65);
}
//int should_draw_bounds() {return 1;}
Geom::Point proj_image (cairo_t *cr, const double pt[4], const vector<Geom::Point> &/*handles*/)
{
double res[3];
for (int j = 0; j < 3; ++j) {
res[j] = 0;
for (int i = 0; i < 3; ++i)
res[j] += tmat[j][i] * pt[i];
}
if (fabs (res[2]) > 0.000001) {
Geom::Point result = Geom::Point (res[0]/res[2], res[1]/res[2]);
draw_handle(cr, result);
return result;
}
assert(0); // unclipped point
return Geom::Point(0,0);
}
};
int main(int argc, char **argv) {
init(argc, argv, new Box3d);
return 0;
}
/*
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:fileencoding=utf-8:textwidth=99 :
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