PerspectiveLine::PerspectiveLine (Geom::Point const &pt, Proj::Axis const axis, Persp3D *persp) :
Line (pt, persp3d_get_VP(persp, axis).affine(), true)
{
g_assert (persp != NULL);
if (!persp3d_get_VP(persp, axis).is_finite()) {
Proj::Pt2 vp(persp3d_get_VP(persp, axis));
this->set_direction(Geom::Point(vp[Proj::X], vp[Proj::Y]));
}
this->vp_dir = axis;
this->persp = persp;
}
/**
* Depending on the value of all_lines, draw the front and/or rear perspective lines starting from the given corners.
*/
void
VPDrag::drawLinesForFace (const SPBox3D *box, Proj::Axis axis) //, guint corner1, guint corner2, guint corner3, guint corner4)
{
guint color;
switch (axis) {
// TODO: Make color selectable by user
case Proj::X: color = VP_LINE_COLOR_STROKE_X; break;
case Proj::Y: color = VP_LINE_COLOR_STROKE_Y; break;
case Proj::Z: color = VP_LINE_COLOR_STROKE_Z; break;
default: g_assert_not_reached();
}
Geom::Point corner1, corner2, corner3, corner4;
box3d_corners_for_PLs (box, axis, corner1, corner2, corner3, corner4);
g_return_if_fail (box3d_get_perspective(box));
Proj::Pt2 vp = persp3d_get_VP (box3d_get_perspective(box), axis);
if (vp.is_finite()) {
// draw perspective lines for finite VPs
Geom::Point pt = vp.affine();
if (this->front_or_rear_lines & 0x1) {
// draw 'front' perspective lines
this->addLine (corner1, pt, color);
this->addLine (corner2, pt, color);
}
if (this->front_or_rear_lines & 0x2) {
// draw 'rear' perspective lines
this->addLine (corner3, pt, color);
this->addLine (corner4, pt, color);
}
} else {
// draw perspective lines for infinite VPs
boost::optional<Geom::Point> pt1, pt2, pt3, pt4;
Persp3D *persp = box3d_get_perspective(box);
SPDesktop *desktop = inkscape_active_desktop (); // FIXME: Store the desktop in VPDrag
Box3D::PerspectiveLine pl (corner1, axis, persp);
pt1 = pl.intersection_with_viewbox(desktop);
pl = Box3D::PerspectiveLine (corner2, axis, persp);
pt2 = pl.intersection_with_viewbox(desktop);
pl = Box3D::PerspectiveLine (corner3, axis, persp);
pt3 = pl.intersection_with_viewbox(desktop);
pl = Box3D::PerspectiveLine (corner4, axis, persp);
pt4 = pl.intersection_with_viewbox(desktop);
if (!pt1 || !pt2 || !pt3 || !pt4) {
// some perspective lines s are outside the canvas; currently we don't draw any of them
return;
}
if (this->front_or_rear_lines & 0x1) {
// draw 'front' perspective lines
this->addLine (corner1, *pt1, color);
this->addLine (corner2, *pt2, color);
}
if (this->front_or_rear_lines & 0x2) {
// draw 'rear' perspective lines
this->addLine (corner3, *pt3, color);
this->addLine (corner4, *pt4, color);
}
}
}
