diff options
Diffstat (limited to 'src/box3d.cpp')
| -rw-r--r-- | src/box3d.cpp | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/src/box3d.cpp b/src/box3d.cpp index 455a7889c..e4bda5d9c 100644 --- a/src/box3d.cpp +++ b/src/box3d.cpp @@ -103,6 +103,8 @@ sp_3dbox_build(SPObject *object, SPDocument *document, Inkscape::XML::Node *repr box->my_counter = counter++; + box->front_bits = 0x0; + if (repr->attribute ("inkscape:perspective") == NULL) { // we are creating a new box; link it to the current perspective Box3D::Perspective3D::current_perspective->add_box (box); @@ -296,6 +298,15 @@ void sp_3dbox_set_ratios (SP3DBox *box, Box3D::Axis axes) } void +sp_3dbox_switch_front_face (SP3DBox *box, Box3D::Axis axis) +{ + if (Box3D::get_persp_of_box (box)->get_vanishing_point (axis)->is_finite()) { + box->front_bits = box->front_bits ^ axis; + } +} + + +void sp_3dbox_position_set (SP3DBoxContext &bc) { SP3DBox *box3d = SP_3DBOX(bc.item); @@ -566,6 +577,83 @@ sp_3dbox_get_svg_descr_of_persp (Box3D::Perspective3D *persp) return g_strdup(os.str().c_str()); } +void sp_3dbox_update_perspective_lines() +{ + SPEventContext *ec = inkscape_active_event_context(); + if (!SP_IS_3DBOX_CONTEXT (ec)) + return; + + SP_3DBOX_CONTEXT (ec)->_vpdrag->updateLines(); +} + +/* + * Manipulates corner1 through corner4 to contain the indices of the corners + * from which the perspective lines in the direction of 'axis' emerge + */ +void sp_3dbox_corners_for_perspective_lines (const SP3DBox * box, Box3D::Axis axis, + NR::Point &corner1, NR::Point &corner2, NR::Point &corner3, NR::Point &corner4) +{ + // along which axis to switch when takint + Box3D::Axis switch_axis; + if (axis == Box3D::X || axis == Box3D::Y) { + switch_axis = (box->front_bits & axis) ? Box3D::Z : Box3D::NONE; + } else { + switch_axis = (box->front_bits & axis) ? Box3D::X : Box3D::NONE; + } + + switch (axis) { + case Box3D::X: + corner1 = sp_3dbox_get_corner_along_edge (box, 0 ^ switch_axis, axis, Box3D::REAR); + corner2 = sp_3dbox_get_corner_along_edge (box, 2 ^ switch_axis, axis, Box3D::REAR); + corner3 = sp_3dbox_get_corner_along_edge (box, 4 ^ switch_axis, axis, Box3D::REAR); + corner4 = sp_3dbox_get_corner_along_edge (box, 6 ^ switch_axis, axis, Box3D::REAR); + break; + case Box3D::Y: + corner1 = sp_3dbox_get_corner_along_edge (box, 0 ^ switch_axis, axis, Box3D::REAR); + corner2 = sp_3dbox_get_corner_along_edge (box, 1 ^ switch_axis, axis, Box3D::REAR); + corner3 = sp_3dbox_get_corner_along_edge (box, 4 ^ switch_axis, axis, Box3D::REAR); + corner4 = sp_3dbox_get_corner_along_edge (box, 5 ^ switch_axis, axis, Box3D::REAR); + break; + case Box3D::Z: + corner1 = sp_3dbox_get_corner_along_edge (box, 1 ^ switch_axis, axis, Box3D::REAR); + corner2 = sp_3dbox_get_corner_along_edge (box, 3 ^ switch_axis, axis, Box3D::REAR); + corner3 = sp_3dbox_get_corner_along_edge (box, 0 ^ switch_axis, axis, Box3D::REAR); + corner4 = sp_3dbox_get_corner_along_edge (box, 2 ^ switch_axis, axis, Box3D::REAR); + break; + } +} + +/** + * Returns the id of the corner on the edge along 'axis' and passing through 'corner' that + * lies on the front/rear face in this direction. + */ +guint +sp_3dbox_get_corner_id_along_edge (const SP3DBox *box, guint corner, Box3D::Axis axis, Box3D::FrontOrRear rel_pos) +{ + guint result; + guint other_corner = corner ^ axis; + Box3D::VanishingPoint *vp = Box3D::get_persp_of_box (box)->get_vanishing_point(axis); + if (vp->is_finite()) { + result = ( NR::L2 (vp->get_pos() - box->corners[corner]) + < NR::L2 (vp->get_pos() - box->corners[other_corner]) ? other_corner : corner); + } else { + // clear the axis bit and switch to the appropriate corner along axis, depending on the value of front_bits + result = ((corner & (0xF ^ axis)) ^ (box->front_bits & axis)); + } + + if (rel_pos == Box3D::FRONT) { + return result; + } else { + return result ^ axis; + } +} + +NR::Point +sp_3dbox_get_corner_along_edge (const SP3DBox *box, guint corner, Box3D::Axis axis, Box3D::FrontOrRear rel_pos) +{ + return box->corners[sp_3dbox_get_corner_id_along_edge (box, corner, axis, rel_pos)]; +} + // auxiliary functions static void sp_3dbox_update_corner_with_value_from_svg (SPObject *object, guint corner_id, const gchar *value) |