spiral-context.cpp

#define __SP_SPIRAL_CONTEXT_C__

/*
 * Spiral drawing context
 *
 * Authors:
 *   Mitsuru Oka
 *   Lauris Kaplinski <lauris@kaplinski.com>
 *   bulia byak <buliabyak@users.sf.net>
 *
 * Copyright (C) 1999-2001 Lauris Kaplinski
 * Copyright (C) 2001-2002 Mitsuru Oka
 *
 * Released under GNU GPL
 */

#include "config.h"

#include <gdk/gdkkeysyms.h>
#include <cstring>
#include <string>

#include "macros.h"
#include "display/sp-canvas.h"
#include "sp-spiral.h"
#include "document.h"
#include "sp-namedview.h"
#include "selection.h"
#include "desktop-handles.h"
#include "desktop-affine.h"
#include "snap.h"
#include "desktop.h"
#include "desktop-style.h"
#include "message-context.h"
#include "pixmaps/cursor-spiral.xpm"
#include "spiral-context.h"
#include "sp-metrics.h"
#include <glibmm/i18n.h>
#include "object-edit.h"
#include "xml/repr.h"
#include "xml/node-event-vector.h"
#include "prefs-utils.h"
#include "context-fns.h"

static void sp_spiral_context_class_init(SPSpiralContextClass * klass);
static void sp_spiral_context_init(SPSpiralContext *spiral_context);
static void sp_spiral_context_dispose(GObject *object);
static void sp_spiral_context_setup(SPEventContext *ec);
static void sp_spiral_context_set(SPEventContext *ec, gchar const *key, gchar const *val);

static gint sp_spiral_context_root_handler(SPEventContext *event_context, GdkEvent *event);

static void sp_spiral_drag(SPSpiralContext *sc, NR::Point p, guint state);
static void sp_spiral_finish(SPSpiralContext *sc);

static SPEventContextClass *parent_class;

GtkType
sp_spiral_context_get_type()
{
    static GType type = 0;
    if (!type) {
        GTypeInfo info = {
            sizeof(SPSpiralContextClass),
            NULL, NULL,
            (GClassInitFunc) sp_spiral_context_class_init,
            NULL, NULL,
            sizeof(SPSpiralContext),
            4,
            (GInstanceInitFunc) sp_spiral_context_init,
            NULL,    /* value_table */
        };
        type = g_type_register_static(SP_TYPE_EVENT_CONTEXT, "SPSpiralContext", &info, (GTypeFlags)0);
    }
    return type;
}

static void
sp_spiral_context_class_init(SPSpiralContextClass *klass)
{
    GObjectClass *object_class = (GObjectClass *) klass;
    SPEventContextClass *event_context_class = (SPEventContextClass *) klass;

    parent_class = (SPEventContextClass*)g_type_class_peek_parent(klass);

    object_class->dispose = sp_spiral_context_dispose;

    event_context_class->setup = sp_spiral_context_setup;
    event_context_class->set = sp_spiral_context_set;
    event_context_class->root_handler = sp_spiral_context_root_handler;
}

static void
sp_spiral_context_init(SPSpiralContext *spiral_context)
{
    SPEventContext *event_context = SP_EVENT_CONTEXT(spiral_context);

    event_context->cursor_shape = cursor_spiral_xpm;
    event_context->hot_x = 4;
    event_context->hot_y = 4;
    event_context->xp = 0;
    event_context->yp = 0;
    event_context->tolerance = 0;
    event_context->within_tolerance = false;
    event_context->item_to_select = NULL;

    event_context->shape_repr = NULL;
    event_context->shape_knot_holder = NULL;

    spiral_context->item = NULL;

    spiral_context->revo = 3.0;
    spiral_context->exp = 1.0;
    spiral_context->t0 = 0.0;

    new (&spiral_context->sel_changed_connection) sigc::connection();
}

static void
sp_spiral_context_dispose(GObject *object)
{
    SPSpiralContext *sc = SP_SPIRAL_CONTEXT(object);
    SPEventContext *ec = SP_EVENT_CONTEXT(object);

    ec->enableGrDrag(false);

    sc->sel_changed_connection.disconnect();
    sc->sel_changed_connection.~connection();

    /* fixme: This is necessary because we do not grab */
    if (sc->item) sp_spiral_finish(sc);

    if (ec->shape_knot_holder) {
        sp_knot_holder_destroy(ec->shape_knot_holder);
        ec->shape_knot_holder = NULL;
    }

    if (ec->shape_repr) { // remove old listener
        sp_repr_remove_listener_by_data(ec->shape_repr, ec);
        Inkscape::GC::release(ec->shape_repr);
        ec->shape_repr = 0;
    }

    if (sc->_message_context) {
        delete sc->_message_context;
    }

    G_OBJECT_CLASS(parent_class)->dispose(object);
}

static Inkscape::XML::NodeEventVector ec_shape_repr_events = {
    NULL, /* child_added */
    NULL, /* child_removed */
    ec_shape_event_attr_changed,
    NULL, /* content_changed */
    NULL  /* order_changed */
};

/**
\brief  Callback that processes the "changed" signal on the selection;
destroys old and creates new knotholder
*/
void
sp_spiral_context_selection_changed(Inkscape::Selection *selection, gpointer data)
{
    SPSpiralContext *sc = SP_SPIRAL_CONTEXT(data);
    SPEventContext *ec = SP_EVENT_CONTEXT(sc);

    if (ec->shape_knot_holder) { // desktroy knotholder
        sp_knot_holder_destroy(ec->shape_knot_holder);
        ec->shape_knot_holder = NULL;
    }

    if (ec->shape_repr) { // remove old listener
        sp_repr_remove_listener_by_data(ec->shape_repr, ec);
        Inkscape::GC::release(ec->shape_repr);
        ec->shape_repr = 0;
    }

    SPItem *item = selection->singleItem();
    if (item) {
        ec->shape_knot_holder = sp_item_knot_holder(item, ec->desktop);
        Inkscape::XML::Node *shape_repr = SP_OBJECT_REPR(item);
        if (shape_repr) {
            ec->shape_repr = shape_repr;
            Inkscape::GC::anchor(shape_repr);
            sp_repr_add_listener(shape_repr, &ec_shape_repr_events, ec);
        }
    }
}

static void
sp_spiral_context_setup(SPEventContext *ec)
{
    SPSpiralContext *sc = SP_SPIRAL_CONTEXT(ec);

    if (((SPEventContextClass *) parent_class)->setup)
        ((SPEventContextClass *) parent_class)->setup(ec);

    sp_event_context_read(ec, "expansion");
    sp_event_context_read(ec, "revolution");
    sp_event_context_read(ec, "t0");

    Inkscape::Selection *selection = sp_desktop_selection(ec->desktop);

    SPItem *item = selection->singleItem();
    if (item) {
        ec->shape_knot_holder = sp_item_knot_holder(item, ec->desktop);
        Inkscape::XML::Node *shape_repr = SP_OBJECT_REPR(item);
        if (shape_repr) {
            ec->shape_repr = shape_repr;
            Inkscape::GC::anchor(shape_repr);
            sp_repr_add_listener(shape_repr, &ec_shape_repr_events, ec);
        }
    }

    sc->sel_changed_connection.disconnect();
    sc->sel_changed_connection = selection->connectChanged(sigc::bind(sigc::ptr_fun(&sp_spiral_context_selection_changed), (gpointer)sc));

    if (prefs_get_int_attribute("tools.shapes", "selcue", 0) != 0) {
        ec->enableSelectionCue();
    }

    if (prefs_get_int_attribute("tools.shapes", "gradientdrag", 0) != 0) {
        ec->enableGrDrag();
    }

    sc->_message_context = new Inkscape::MessageContext((ec->desktop)->messageStack());
}

static void
sp_spiral_context_set(SPEventContext *ec, gchar const *key, gchar const *val)
{
    SPSpiralContext *sc = SP_SPIRAL_CONTEXT(ec);

    if (!strcmp(key, "expansion")) {
        sc->exp = (val) ? g_ascii_strtod(val, NULL) : 1.0;
        sc->exp = CLAMP(sc->exp, 0.0, 1000.0);
    } else if (!strcmp(key, "revolution")) {
        sc->revo = (val) ? g_ascii_strtod(val, NULL) : 3.0;
        sc->revo = CLAMP(sc->revo, 0.05, 40.0);
    } else if (!strcmp(key, "t0")) {
        sc->t0 = (val) ? g_ascii_strtod(val, NULL) : 0.0;
        sc->t0 = CLAMP(sc->t0, 0.0, 0.999);
    }
}

static gint
sp_spiral_context_root_handler(SPEventContext *event_context, GdkEvent *event)
{
    static gboolean dragging;

    SPDesktop *desktop = event_context->desktop;
    Inkscape::Selection *selection = sp_desktop_selection (desktop);
    SPSpiralContext *sc = SP_SPIRAL_CONTEXT(event_context);

    event_context->tolerance = prefs_get_int_attribute_limited("options.dragtolerance", "value", 0, 0, 100);

    gint ret = FALSE;

    switch (event->type) {
        case GDK_BUTTON_PRESS:
            if (event->button.button == 1 && !event_context->space_panning) {

                dragging = TRUE;
                sc->center = Inkscape::setup_for_drag_start(desktop, event_context, event);

                SnapManager const &m = desktop->namedview->snap_manager;
                sc->center = m.freeSnap(Inkscape::Snapper::SNAPPOINT_NODE, sc->center, sc->item).getPoint();

                sp_canvas_item_grab(SP_CANVAS_ITEM(desktop->acetate),
                                    ( GDK_KEY_PRESS_MASK |
                                      GDK_BUTTON_RELEASE_MASK |
                                      GDK_POINTER_MOTION_MASK |
                                      GDK_BUTTON_PRESS_MASK    ),
                                    NULL, event->button.time);
                ret = TRUE;
            }
            break;
        case GDK_MOTION_NOTIFY:
            if (dragging && (event->motion.state & GDK_BUTTON1_MASK) && !event_context->space_panning) {

                if ( event_context->within_tolerance
                     && ( abs( (gint) event->motion.x - event_context->xp ) < event_context->tolerance )
                     && ( abs( (gint) event->motion.y - event_context->yp ) < event_context->tolerance ) ) {
                    break; // do not drag if we're within tolerance from origin
                }
                // Once the user has moved farther than tolerance from the original location
                // (indicating they intend to draw, not click), then always process the
                // motion notify coordinates as given (no snapping back to origin)
                event_context->within_tolerance = false;

                NR::Point const motion_w(event->motion.x, event->motion.y);
                NR::Point motion_dt(event_context->desktop->w2d(motion_w));
                
                SnapManager const &m = desktop->namedview->snap_manager;
                motion_dt = m.freeSnap(Inkscape::Snapper::SNAPPOINT_NODE, motion_dt, sc->item).getPoint();
                sp_spiral_drag(sc, motion_dt, event->motion.state);

                gobble_motion_events(GDK_BUTTON1_MASK);

                ret = TRUE;
            }
            break;
        case GDK_BUTTON_RELEASE:
            event_context->xp = event_context->yp = 0;
            if (event->button.button == 1 && !event_context->space_panning) {
                dragging = FALSE;
                if (!event_context->within_tolerance) {
                    // we've been dragging, finish the spiral
                    sp_spiral_finish(sc);
                } else if (event_context->item_to_select) {
                    // no dragging, select clicked item if any
                    if (event->button.state & GDK_SHIFT_MASK) {
                        selection->toggle(event_context->item_to_select);
                    } else {
                        selection->set(event_context->item_to_select);
                    }
                } else {
                    // click in an empty space
                    selection->clear();
                }

                event_context->item_to_select = NULL;
                ret = TRUE;
                sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate), event->button.time);
            }
            break;
        case GDK_KEY_PRESS:
            switch (get_group0_keyval(&event->key)) {
                case GDK_Alt_R:
                case GDK_Control_L:
                case GDK_Control_R:
                case GDK_Shift_L:
                case GDK_Shift_R:
                case GDK_Meta_L:  // Meta is when you press Shift+Alt (at least on my machine)
                case GDK_Meta_R:
                    sp_event_show_modifier_tip(event_context->defaultMessageContext(), event,
                                               _("<b>Ctrl</b>: snap angle"),
                                               NULL,
                                               _("<b>Alt</b>: lock spiral radius"));
                    break;
                case GDK_Up:
                case GDK_Down:
                case GDK_KP_Up:
                case GDK_KP_Down:
                    // prevent the zoom field from activation
                    if (!MOD__CTRL_ONLY)
                        ret = TRUE;
                    break;
                case GDK_x:
                case GDK_X:
                    if (MOD__ALT_ONLY) {
                        desktop->setToolboxFocusTo ("altx-spiral");
                        ret = TRUE;
                    }
                    break;
                case GDK_Escape:
                    sp_desktop_selection(desktop)->clear();
                    //TODO: make dragging escapable by Esc
                    break;

                case GDK_space:
                    if (dragging) {
                        sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate),
                                              event->button.time);
                        dragging = false;
                        if (!event_context->within_tolerance) {
                            // we've been dragging, finish the rect
                            sp_spiral_finish(sc);
                        }
                        // do not return true, so that space would work switching to selector
                    }
                    break;

                default:
                    break;
            }
            break;
        case GDK_KEY_RELEASE:
            switch (get_group0_keyval(&event->key)) {
                case GDK_Alt_L:
                case GDK_Alt_R:
                case GDK_Control_L:
                case GDK_Control_R:
                case GDK_Shift_L:
                case GDK_Shift_R:
                case GDK_Meta_L:  // Meta is when you press Shift+Alt
                case GDK_Meta_R:
                    event_context->defaultMessageContext()->clear();
                    break;
                default:
                    break;
            }
            break;
        default:
            break;
    }

    if (!ret) {
        if (((SPEventContextClass *) parent_class)->root_handler)
            ret = ((SPEventContextClass *) parent_class)->root_handler(event_context, event);
    }

    return ret;
}

static void
sp_spiral_drag(SPSpiralContext *sc, NR::Point p, guint state)
{
    SPDesktop *desktop = SP_EVENT_CONTEXT(sc)->desktop;

    int const snaps = prefs_get_int_attribute("options.rotationsnapsperpi", "value", 12);

    if (!sc->item) {

        if (Inkscape::have_viable_layer(desktop, sc->_message_context) == false) {
            return;
        }

        /* Create object */
        Inkscape::XML::Document *xml_doc = sp_document_repr_doc(SP_EVENT_CONTEXT_DOCUMENT(sc));
        Inkscape::XML::Node *repr = xml_doc->createElement("svg:path");
        repr->setAttribute("sodipodi:type", "spiral");

        /* Set style */
        sp_desktop_apply_style_tool(desktop, repr, "tools.shapes.spiral", false);

        sc->item = (SPItem *) desktop->currentLayer()->appendChildRepr(repr);
        Inkscape::GC::release(repr);
        sc->item->transform = SP_ITEM(desktop->currentRoot())->getRelativeTransform(desktop->currentLayer());
        sc->item->updateRepr();

        sp_canvas_force_full_redraw_after_interruptions(desktop->canvas, 5);
    }

    NR::Point const p0 = sp_desktop_dt2root_xy_point(desktop, sc->center);
    NR::Point p1 = sp_desktop_dt2root_xy_point(desktop, p);
    SnapManager const &m = desktop->namedview->snap_manager;
    p1 = m.freeSnap(Inkscape::Snapper::SNAPPOINT_NODE, p1, sc->item).getPoint();

    SPSpiral *spiral = SP_SPIRAL(sc->item);

    NR::Point const delta = p1 - p0;
    gdouble const rad = NR::L2(delta);

    gdouble arg = NR::atan2(delta) - 2.0*M_PI*spiral->revo;

    if (state & GDK_CONTROL_MASK) {
        arg = sp_round(arg, M_PI/snaps);
    }

    /* Fixme: these parameters should be got from dialog box */
    sp_spiral_position_set(spiral, p0[NR::X], p0[NR::Y],
                           /*expansion*/ sc->exp,
                           /*revolution*/ sc->revo,
                           rad, arg,
                           /*t0*/ sc->t0);

    /* status text */
    GString *rads = SP_PX_TO_METRIC_STRING(rad, desktop->namedview->getDefaultMetric());
    sc->_message_context->setF(Inkscape::IMMEDIATE_MESSAGE,
                               _("<b>Spiral</b>: radius %s, angle %5g&#176;; with <b>Ctrl</b> to snap angle"),
                               rads->str, sp_round((arg + 2.0*M_PI*spiral->revo)*180/M_PI, 0.0001));
    g_string_free(rads, FALSE);
}

static void
sp_spiral_finish(SPSpiralContext *sc)
{
    sc->_message_context->clear();

    if (sc->item != NULL) {
        SPDesktop *desktop = SP_EVENT_CONTEXT(sc)->desktop;
        SPSpiral  *spiral = SP_SPIRAL(sc->item);

        sp_shape_set_shape(SP_SHAPE(spiral));
        SP_OBJECT(spiral)->updateRepr(SP_OBJECT_WRITE_EXT);

        sp_canvas_end_forced_full_redraws(desktop->canvas);

        sp_desktop_selection(desktop)->set(sc->item);
        sp_document_done(sp_desktop_document(desktop), SP_VERB_CONTEXT_SPIRAL, 
                         _("Create spiral"));

        sc->item = NULL;
    }
}


/*
  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:encoding=utf-8:textwidth=99 :