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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;
unsigned total_pieces_sub;
unsigned total_pieces_inc;
void cairo_pw(cairo_t *cr, Piecewise<SBasis> p) {
for(unsigned i = 0; i < p.size(); i++) {
D2<SBasis> B;
B[0] = Linear(p.cuts[i], p.cuts[i+1]);
B[1] = p[i];
cairo_d2_sb(cr, B);
}
}
Geom::Point orig;
static void draw_box (cairo_t *cr, Geom::Point corners[8]);
static void draw_slider_lines (cairo_t *cr);
static Geom::Point proj_image (cairo_t *cr, const double pt[4], const vector<Geom::Point> &handles);
double tmat[3][4];
double c[8][4];
Geom::Point corners[8];
class Box3d: public Toy {
std::vector<Toggle> togs;
Path path_a;
Piecewise<D2<SBasis> > path_a_pw;
PointSetHandle hand;
void draw(cairo_t *cr, std::ostringstream *notify, int width, int height, bool save, std::ostringstream *timer_stream) override {
orig = hand.pts[7];
Geom::Point dir(1,-2);
cairo_set_source_rgba (cr, 0., 0.125, 0, 1);
// draw vertical lines for the VP sliders and keep the sliders at their horizontal positions
draw_slider_lines (cr);
hand.pts[4][0] = 30;
hand.pts[5][0] = 45;
hand.pts[6][0] = 60;
// draw the curve that is supposed to be projected on the box's front face
vector<Geom::Point>::iterator it = hand.pts.begin();
for (int j = 0; j < 7; ++j) ++it;
/* 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] = hand.pts[j][0];
tmat[1][j] = hand.pts[j][1];
tmat[2][j] = 1;
}
*notify << "Projection matrix:" << endl;
for (auto & i : tmat) {
for (double j : i) {
*notify << j << " ";
}
*notify << endl;
}
// draw the projective images of the box's corners
for (int i = 0; i < 8; ++i) {
corners[i] = proj_image (cr, c[i], hand.pts);
}
draw_box(cr, corners);
cairo_set_line_width (cr, 2);
cairo_stroke(cr);
{
D2<Piecewise<SBasis> > B = make_cuts_independent(path_a_pw);
Piecewise<SBasis> preimage[4];
if(togs[0].on) {
preimage[0] = sin((B[0] - orig[0]) / 100);
preimage[1] = -(B[1] - orig[1]) / 100;
preimage[2] = cos((B[0] - orig[0]) / 100);
} else { //if(togs[1].state) {
Piecewise<SBasis> sphi = sin((B[0] - orig[0]) / 200);
Piecewise<SBasis> cphi = cos((B[0] - orig[0]) / 200);
preimage[0] = -sphi*sin((B[1] - orig[1]) / 200);
preimage[1] = -sphi*cos((B[1] - orig[1]) / 200);
preimage[2] = -cphi;
}
Piecewise<SBasis> res[3];
for (int j = 0; j < 3; ++j) {
res[j] =
(preimage[0]) * tmat[j][0]
+ (preimage[1] - ((hand.pts[5][1]-300)/100)) * tmat[j][1]
+ (preimage[2] - ((hand.pts[6][1]-00)/100)) * tmat[j][2]
+( - (hand.pts[4][1]-300)/100) * tmat[j][0] + tmat[j][3];
}
//if (fabs (res[2]) > 0.000001) {
D2<Piecewise<SBasis> > result(divide(res[0],res[2], 4),
divide(res[1],res[2], 4));
cairo_d2_pw_sb(cr, result);
cairo_set_source_rgba (cr, 0., 0.125, 0, 1);
cairo_stroke(cr);
}
draw_toggles(cr, togs);
Toy::draw(cr, notify, width, height, save,timer_stream);
}
void first_time(int argc, char** argv) override {
const char *path_a_name="star.svgd";
if(argc > 1)
path_a_name = argv[1];
PathVector paths_a = read_svgd(path_a_name);
assert(!paths_a.empty());
path_a = paths_a[0];
path_a.close(true);
path_a_pw = path_a.toPwSb();
// Finite images of the three vanishing points and the origin
hand.pts.emplace_back(150,300);
hand.pts.emplace_back(380,40);
hand.pts.emplace_back(550,350);
hand.pts.emplace_back(340,450);
// Hand.Pts for moving in axes directions
hand.pts.emplace_back(30,300);
hand.pts.emplace_back(45,300);
hand.pts.emplace_back(60,300);
// Box corners
for (int i = 0; i < 8; ++i) {
c[i][0] = ((i & 1) ? 1 : 0);
c[i][1] = ((i & 2) ? 1 : 0);
c[i][2] = ((i & 4) ? 1 : 0);
c[i][3] = 1;
}
// Origin handle
hand.pts.emplace_back(180,70);
togs.emplace_back("S", true);
handles.push_back(&hand);
}
void key_hit(GdkEventKey *e) override {
if(e->keyval == 'c') togs[0].set(1); else
if(e->keyval == 's') togs[0].set(0);
redraw();
}
void mouse_pressed(GdkEventButton* e) override {
toggle_events(togs, e);
Toy::mouse_pressed(e);
}
};
int main(int argc, char **argv) {
init(argc, argv, new Box3d);
return 0;
}
void draw_box (cairo_t *cr, Geom::Point corners[8]) {
cairo_move_to(cr,corners[0]);
cairo_line_to(cr,corners[1]);
cairo_line_to(cr,corners[3]);
cairo_line_to(cr,corners[2]);
cairo_close_path(cr);
cairo_move_to(cr,corners[4]);
cairo_line_to(cr,corners[5]);
cairo_line_to(cr,corners[7]);
cairo_line_to(cr,corners[6]);
cairo_close_path(cr);
cairo_move_to(cr,corners[0]);
cairo_line_to(cr,corners[4]);
cairo_move_to(cr,corners[1]);
cairo_line_to(cr,corners[5]);
cairo_move_to(cr,corners[2]);
cairo_line_to(cr,corners[6]);
cairo_move_to(cr,corners[3]);
cairo_line_to(cr,corners[7]);
}
void draw_slider_lines (cairo_t *cr) {
cairo_move_to(cr, Geom::Point(20,300));
cairo_line_to(cr, Geom::Point(70,300));
cairo_move_to(cr, Geom::Point(30,00));
cairo_line_to(cr, Geom::Point(30,450));
cairo_move_to(cr, Geom::Point(45,00));
cairo_line_to(cr, Geom::Point(45,450));
cairo_move_to(cr, Geom::Point(60,00));
cairo_line_to(cr, Geom::Point(60,450));
cairo_set_line_width (cr, 1);
cairo_set_source_rgba (cr, 0.2, 0.2, 0.2, 1);
cairo_stroke(cr);
}
static 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] =
tmat[j][0] * (pt[0] - (handles[4][1]-300)/100)
+ tmat[j][1] * (pt[1] - (handles[5][1]-300)/100)
+ tmat[j][2] * (pt[2] - (handles[6][1]-300)/100)
+ tmat[j][3] * pt[3];
}
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);
}
/*
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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