/* multiply a projective matrix by an affine matrix */
TransfMat3x4
TransfMat3x4::operator*(Geom::Matrix const &A) const {
TransfMat3x4 ret;
// Is it safe to always use the currently active document?
double h = sp_document_height(inkscape_active_document());
/*
* Note: The strange multiplication involving the document height is due to the buggy
* intertwining of SVG and document coordinates. Essentially, what we do is first
* convert from "real-world" to SVG coordinates, then apply the transformation A
* (by multiplying with the Geom::Matrix) and then convert back from SVG to real-world
* coordinates. Maybe there is even a more Inkscape-ish way to achieve this?
* Once Inkscape has gotton rid of the two different coordiate systems, we can change
* this function to an ordinary matrix multiplication.
*/
for (int j = 0; j < 4; ++j) {
ret.tmat[0][j] = A[0]*tmat[0][j] + A[2]*(h*tmat[2][j] - tmat[1][j]) + A[4]*tmat[2][j];
ret.tmat[1][j] = A[1]*tmat[0][j] + A[3]*(h*tmat[2][j] - tmat[1][j]) + A[5]*tmat[2][j];
ret.tmat[2][j] = tmat[2][j];
ret.tmat[1][j] = h*ret.tmat[2][j] - ret.tmat[1][j]; // switch back from SVG to desktop coordinates
}
return ret;
}
static void sp_box3d_drag(Box3DContext &bc, guint /*state*/)
{
SPDesktop *desktop = SP_EVENT_CONTEXT(&bc)->desktop;
if (!bc.item) {
if (Inkscape::have_viable_layer(desktop, bc._message_context) == false) {
return;
}
/* Create object */
Inkscape::XML::Document *xml_doc = sp_document_repr_doc(SP_EVENT_CONTEXT_DOCUMENT(&bc));
Inkscape::XML::Node *repr = xml_doc->createElement("svg:g");
repr->setAttribute("sodipodi:type", "inkscape:box3d");
/* Set style */
sp_desktop_apply_style_tool (desktop, repr, "/tools/shapes/3dbox", false);
bc.item = (SPItem *) desktop->currentLayer()->appendChildRepr(repr);
Inkscape::GC::release(repr);
Inkscape::XML::Node *repr_side;
// TODO: Incorporate this in box3d-side.cpp!
for (int i = 0; i < 6; ++i) {
repr_side = xml_doc->createElement("svg:path");
repr_side->setAttribute("sodipodi:type", "inkscape:box3dside");
repr->addChild(repr_side, NULL);
Box3DSide *side = SP_BOX3D_SIDE(inkscape_active_document()->getObjectByRepr (repr_side));
guint desc = Box3D::int_to_face(i);
Box3D::Axis plane = (Box3D::Axis) (desc & 0x7);
plane = (Box3D::is_plane(plane) ? plane : Box3D::orth_plane_or_axis(plane));
side->dir1 = Box3D::extract_first_axis_direction(plane);
side->dir2 = Box3D::extract_second_axis_direction(plane);
side->front_or_rear = (Box3D::FrontOrRear) (desc & 0x8);
/* Set style */
box3d_side_apply_style(side);
SP_OBJECT(side)->updateRepr(); // calls box3d_side_write() and updates, e.g., the axes string description
}
box3d_set_z_orders(SP_BOX3D(bc.item));
bc.item->updateRepr();
// TODO: It would be nice to show the VPs during dragging, but since there is no selection
// at this point (only after finishing the box), we must do this "manually"
/* bc._vpdrag->updateDraggers(); */
desktop->canvas->force_full_redraw_after_interruptions(5);
}
g_assert(bc.item);
SPBox3D *box = SP_BOX3D(bc.item);
box->orig_corner0 = bc.drag_origin_proj;
box->orig_corner7 = bc.drag_ptC_proj;
box3d_check_for_swapped_coords(box);
/* we need to call this from here (instead of from box3d_position_set(), for example)
because z-order setting must not interfere with display updates during undo/redo */
box3d_set_z_orders (box);
box3d_position_set(box);
// status text
bc._message_context->setF(Inkscape::NORMAL_MESSAGE, "%s", _("<b>3D Box</b>; with <b>Shift</b> to extrude along the Z axis"));
}
