~centralelyon2010/inkscape/imagelinks2

/*

 * <sodipodi:star> implementation

 *

 * Authors:

 *   Mitsuru Oka <oka326@parkcity.ne.jp>

 *   Lauris Kaplinski <lauris@kaplinski.com>

 *   bulia byak <buliabyak@users.sf.net>

 *   Abhishek Sharma

 *

 * Copyright (C) 1999-2002 Lauris Kaplinski

 * Copyright (C) 2000-2001 Ximian, Inc.

 *

 * Released under GNU GPL, read the file 'COPYING' for more information

 */

#ifdef HAVE_CONFIG_H

# include "config.h"

#endif

#include <cstring>

#include <string>

#include <glib.h>

#include <glibmm/i18n.h>

#include "svg/svg.h"

#include "attributes.h"

#include "display/curve.h"

#include "xml/repr.h"

#include "document.h"

#include <2geom/pathvector.h>

#include "sp-star.h"

static void sp_star_class_init (SPStarClass *klass);

static void sp_star_init (SPStar *star);

static void sp_star_build (SPObject * object, SPDocument * document, Inkscape::XML::Node * repr);

static Inkscape::XML::Node *sp_star_write (SPObject *object, Inkscape::XML::Document *doc, Inkscape::XML::Node *repr, guint flags);

static void sp_star_set (SPObject *object, unsigned int key, const gchar *value);

static void sp_star_update (SPObject *object, SPCtx *ctx, guint flags);

static gchar * sp_star_description (SPItem * item);

static void sp_star_snappoints(SPItem const *item, std::vector<Inkscape::SnapCandidatePoint> &p, Inkscape::SnapPreferences const *snapprefs);

static void sp_star_set_shape (SPShape *shape);

static void sp_star_update_patheffect (SPLPEItem *lpeitem, bool write);

static SPShapeClass *parent_class;

GType

sp_star_get_type (void)

{

    static GType type = 0;

    if (!type) {

        GTypeInfo info = {

            sizeof (SPStarClass),

            NULL, NULL,

            (GClassInitFunc) sp_star_class_init,

            NULL, NULL,

            sizeof (SPStar),

            16,

            (GInstanceInitFunc) sp_star_init,

            NULL,    /* value_table */

        };

        type = g_type_register_static (SP_TYPE_SHAPE, "SPStar", &info, (GTypeFlags)0);

    }

    return type;

}

static void

sp_star_class_init (SPStarClass *klass)

{

    GObjectClass * gobject_class;

    SPObjectClass * sp_object_class;

    SPItemClass * item_class;

    SPLPEItemClass * lpe_item_class;

    SPShapeClass * shape_class;

    gobject_class = (GObjectClass *) klass;

    sp_object_class = (SPObjectClass *) klass;

    item_class = (SPItemClass *) klass;

    lpe_item_class = (SPLPEItemClass *) klass;

    shape_class = (SPShapeClass *) klass;

    parent_class = (SPShapeClass *)g_type_class_ref (SP_TYPE_SHAPE);

    sp_object_class->build = sp_star_build;

    sp_object_class->write = sp_star_write;

    sp_object_class->set = sp_star_set;

    sp_object_class->update = sp_star_update;

    item_class->description = sp_star_description;

    item_class->snappoints = sp_star_snappoints;

    lpe_item_class->update_patheffect = sp_star_update_patheffect;

    shape_class->set_shape = sp_star_set_shape;

}

static void

sp_star_init (SPStar * star)

{

    star->sides = 5;

    star->center = Geom::Point(0, 0);

    star->r[0] = 1.0;

    star->r[1] = 0.001;

    star->arg[0] = star->arg[1] = 0.0;

    star->flatsided = 0;

    star->rounded = 0.0;

    star->randomized = 0.0;

}

static void

sp_star_build (SPObject * object, SPDocument * document, Inkscape::XML::Node * repr)

{

    if (((SPObjectClass *) parent_class)->build)

        ((SPObjectClass *) parent_class)->build (object, document, repr);

    object->readAttr( "sodipodi:cx" );

    object->readAttr( "sodipodi:cy" );

    object->readAttr( "sodipodi:sides" );

    object->readAttr( "sodipodi:r1" );

    object->readAttr( "sodipodi:r2" );

    object->readAttr( "sodipodi:arg1" );

    object->readAttr( "sodipodi:arg2" );

    object->readAttr( "inkscape:flatsided" );

    object->readAttr( "inkscape:rounded" );

    object->readAttr( "inkscape:randomized" );

}

static Inkscape::XML::Node *

sp_star_write (SPObject *object, Inkscape::XML::Document *xml_doc, Inkscape::XML::Node *repr, guint flags)

{

    SPStar *star = SP_STAR (object);

    if ((flags & SP_OBJECT_WRITE_BUILD) && !repr) {

        repr = xml_doc->createElement("svg:path");

    }

    if (flags & SP_OBJECT_WRITE_EXT) {

        repr->setAttribute("sodipodi:type", "star");

        sp_repr_set_int (repr, "sodipodi:sides", star->sides);

        sp_repr_set_svg_double(repr, "sodipodi:cx", star->center[Geom::X]);

        sp_repr_set_svg_double(repr, "sodipodi:cy", star->center[Geom::Y]);

        sp_repr_set_svg_double(repr, "sodipodi:r1", star->r[0]);

        sp_repr_set_svg_double(repr, "sodipodi:r2", star->r[1]);

        sp_repr_set_svg_double(repr, "sodipodi:arg1", star->arg[0]);

        sp_repr_set_svg_double(repr, "sodipodi:arg2", star->arg[1]);

        sp_repr_set_boolean (repr, "inkscape:flatsided", star->flatsided);

        sp_repr_set_svg_double(repr, "inkscape:rounded", star->rounded);

        sp_repr_set_svg_double(repr, "inkscape:randomized", star->randomized);

    }

    sp_star_set_shape ((SPShape *) star);

    char *d = sp_svg_write_path (((SPShape *) star)->curve->get_pathvector());

    repr->setAttribute("d", d);

    g_free (d);

    if (((SPObjectClass *) (parent_class))->write)

        ((SPObjectClass *) (parent_class))->write (object, xml_doc, repr, flags);

    return repr;

}

static void

sp_star_set (SPObject *object, unsigned int key, const gchar *value)

{

    SVGLength::Unit unit;

    SPStar *star = SP_STAR (object);

    /* fixme: we should really collect updates */

    switch (key) {

    case SP_ATTR_SODIPODI_SIDES:

        if (value) {

            star->sides = atoi (value);

            star->sides = CLAMP(star->sides, 3, 1024);

        } else {

            star->sides = 5;

        }

        object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);

        break;

    case SP_ATTR_SODIPODI_CX:

        if (!sp_svg_length_read_ldd (value, &unit, NULL, &star->center[Geom::X]) ||

            (unit == SVGLength::EM) ||

            (unit == SVGLength::EX) ||

            (unit == SVGLength::PERCENT)) {

            star->center[Geom::X] = 0.0;

        }

        object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);

        break;

    case SP_ATTR_SODIPODI_CY:

        if (!sp_svg_length_read_ldd (value, &unit, NULL, &star->center[Geom::Y]) ||

            (unit == SVGLength::EM) ||

            (unit == SVGLength::EX) ||

            (unit == SVGLength::PERCENT)) {

            star->center[Geom::Y] = 0.0;

        }

        object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);

        break;

    case SP_ATTR_SODIPODI_R1:

        if (!sp_svg_length_read_ldd (value, &unit, NULL, &star->r[0]) ||

            (unit == SVGLength::EM) ||

            (unit == SVGLength::EX) ||

            (unit == SVGLength::PERCENT)) {

            star->r[0] = 1.0;

        }

        /* fixme: Need CLAMP (Lauris) */

        object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);

        break;

    case SP_ATTR_SODIPODI_R2:

        if (!sp_svg_length_read_ldd (value, &unit, NULL, &star->r[1]) ||

            (unit == SVGLength::EM) ||

            (unit == SVGLength::EX) ||

            (unit == SVGLength::PERCENT)) {

            star->r[1] = 0.0;

        }

        object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);

        return;

    case SP_ATTR_SODIPODI_ARG1:

        if (value) {

            star->arg[0] = g_ascii_strtod (value, NULL);

        } else {

            star->arg[0] = 0.0;

        }

        object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);

        break;

    case SP_ATTR_SODIPODI_ARG2:

        if (value) {

            star->arg[1] = g_ascii_strtod (value, NULL);

        } else {

            star->arg[1] = 0.0;

        }

        object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);

        break;

    case SP_ATTR_INKSCAPE_FLATSIDED:

        if (value && !strcmp (value, "true"))

            star->flatsided = true;

        else star->flatsided = false;

        object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);

        break;

    case SP_ATTR_INKSCAPE_ROUNDED:

        if (value) {

            star->rounded = g_ascii_strtod (value, NULL);

        } else {

            star->rounded = 0.0;

        }

        object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);

        break;

    case SP_ATTR_INKSCAPE_RANDOMIZED:

        if (value) {

            star->randomized = g_ascii_strtod (value, NULL);

        } else {

            star->randomized = 0.0;

        }

        object->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);

        break;

    default:

        if (((SPObjectClass *) parent_class)->set)

            ((SPObjectClass *) parent_class)->set (object, key, value);

        break;

    }

}

static void

sp_star_update (SPObject *object, SPCtx *ctx, guint flags)

{

    if (flags & (SP_OBJECT_MODIFIED_FLAG |

             SP_OBJECT_STYLE_MODIFIED_FLAG |

             SP_OBJECT_VIEWPORT_MODIFIED_FLAG)) {

        ((SPShape *) object)->setShape ();

    }

    if (((SPObjectClass *) parent_class)->update)

        ((SPObjectClass *) parent_class)->update (object, ctx, flags);

}

static void

sp_star_update_patheffect(SPLPEItem *lpeitem, bool write)

{

    SPShape *shape = (SPShape *) lpeitem;

    sp_star_set_shape(shape);

    if (write) {

        Inkscape::XML::Node *repr = shape->getRepr();

        if ( shape->curve != NULL ) {

            gchar *str = sp_svg_write_path(shape->curve->get_pathvector());

            repr->setAttribute("d", str);

            g_free(str);

        } else {

            repr->setAttribute("d", NULL);

        }

    }

    ((SPObject *)shape)->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);

}

static gchar *

sp_star_description (SPItem *item)

{

    SPStar *star = SP_STAR (item);

    // while there will never be less than 3 vertices, we still need to

    // make calls to ngettext because the pluralization may be different

    // for various numbers >=3.  The singular form is used as the index.

    if (star->flatsided == false )

    return g_strdup_printf (ngettext("<b>Star</b> with %d vertex",

                         "<b>Star</b> with %d vertices",

                     star->sides), star->sides);

    else

        return g_strdup_printf (ngettext("<b>Polygon</b> with %d vertex",

                         "<b>Polygon</b> with %d vertices",

                     star->sides), star->sides);

}

/**

Returns a unit-length vector at 90 degrees to the direction from o to n

 */

static Geom::Point

rot90_rel (Geom::Point o, Geom::Point n)

{

    return ((1/Geom::L2(n - o)) * Geom::Point ((n - o)[Geom::Y],  (o - n)[Geom::X]));

}

/**

Returns a unique 32 bit int for a given point.

Obvious (but acceptable for my purposes) limits to uniqueness:

- returned value for x,y repeats for x+n*1024,y+n*1024

- returned value is unchanged when the point is moved by less than 1/1024 of px

*/

static guint32

point_unique_int (Geom::Point o)

{

    return ((guint32)

    65536 *

        (((int) floor (o[Geom::X] * 64)) % 1024 + ((int) floor (o[Geom::X] * 1024)) % 64)

    +

             (((int) floor (o[Geom::Y] * 64)) % 1024 + ((int) floor (o[Geom::Y] * 1024)) % 64)

    );

}

/**

Returns the next pseudorandom value using the Linear Congruential Generator algorithm (LCG)

with the parameters (m = 2^32, a = 69069, b = 1). These parameters give a full-period generator,

i.e. it is guaranteed to go through all integers < 2^32 (see http://random.mat.sbg.ac.at/~charly/server/server.html)

*/

static inline guint32

lcg_next(guint32 const prev)

{

    return (guint32) ( 69069 * prev + 1 );

}

/**

Returns a random number in the range [-0.5, 0.5) from the given seed, stepping the given number of steps from the seed.

*/

static double

rnd (guint32 const seed, unsigned steps) {

    guint32 lcg = seed;

    for (; steps > 0; steps --)

        lcg = lcg_next (lcg);

    return ( lcg / 4294967296. ) - 0.5;

}

static Geom::Point

sp_star_get_curvepoint (SPStar *star, SPStarPoint point, gint index, bool previ)

{

    // the point whose neighboring curve handle we're calculating

    Geom::Point o = sp_star_get_xy (star, point, index);

    // indices of previous and next points

    gint pi = (index > 0)? (index - 1) : (star->sides - 1);

    gint ni = (index < star->sides - 1)? (index + 1) : 0;

    // the other point type

    SPStarPoint other = (point == SP_STAR_POINT_KNOT2? SP_STAR_POINT_KNOT1 : SP_STAR_POINT_KNOT2);

    // the neighbors of o; depending on flatsided, they're either the same type (polygon) or the other type (star)

    Geom::Point prev = (star->flatsided? sp_star_get_xy (star, point, pi) : sp_star_get_xy (star, other, point == SP_STAR_POINT_KNOT2? index : pi));

    Geom::Point next = (star->flatsided? sp_star_get_xy (star, point, ni) : sp_star_get_xy (star, other, point == SP_STAR_POINT_KNOT1? index : ni));

    // prev-next midpoint

    Geom::Point mid =  0.5 * (prev + next);

    // point to which we direct the bissector of the curve handles;

    // it's far enough outside the star on the perpendicular to prev-next through mid

    Geom::Point biss =  mid + 100000 * rot90_rel (mid, next);

    // lengths of vectors to prev and next

    gdouble prev_len = Geom::L2 (prev - o);

    gdouble next_len = Geom::L2 (next - o);

    // unit-length vector perpendicular to o-biss

    Geom::Point rot = rot90_rel (o, biss);

    // multiply rot by star->rounded coefficient and the distance to the star point; flip for next

    Geom::Point ret;

    if (previ) {

        ret = (star->rounded * prev_len) * rot;

    } else {

        ret = (star->rounded * next_len * -1) * rot;

    }

    if (star->randomized == 0) {

        // add the vector to o to get the final curvepoint

        return o + ret;

    } else {

        // the seed corresponding to the exact point

        guint32 seed = point_unique_int (o);

        // randomly rotate (by step 3 from the seed) and scale (by step 4) the vector

        ret = ret * Geom::Affine (Geom::Rotate (star->randomized * M_PI * rnd (seed, 3)));

        ret *= ( 1 + star->randomized * rnd (seed, 4));

        // the randomized corner point

        Geom::Point o_randomized = sp_star_get_xy (star, point, index, true);

        return o_randomized + ret;

    }

}

#define NEXT false

#define PREV true

static void

sp_star_set_shape (SPShape *shape)

{

    SPStar *star = SP_STAR (shape);

    // perhaps we should convert all our shapes into LPEs without source path

    // and with knotholders for parameters, then this situation will be handled automatically

    // by disabling the entire stack (including the shape LPE)

    if (sp_lpe_item_has_broken_path_effect(SP_LPE_ITEM(shape))) {

        g_warning ("The star shape has unknown LPE on it! Convert to path to make it editable preserving the appearance; editing it as star will remove the bad LPE");

        if (shape->getRepr()->attribute("d")) {

            // unconditionally read the curve from d, if any, to preserve appearance

            Geom::PathVector pv = sp_svg_read_pathv(shape->getRepr()->attribute("d"));

            SPCurve *cold = new SPCurve(pv);

            shape->setCurveInsync( cold, TRUE);

            shape->setCurveBeforeLPE(cold);

            cold->unref();

        }

        return;

    }

    SPCurve *c = new SPCurve ();

    gint sides = star->sides;

    bool not_rounded = (fabs (star->rounded) < 1e-4);

    // note that we pass randomized=true to sp_star_get_xy, because the curve must be randomized;

    // other places that call that function (e.g. the knotholder) need the exact point

    // draw 1st segment

    c->moveto(sp_star_get_xy (star, SP_STAR_POINT_KNOT1, 0, true));

    if (star->flatsided == false) {

        if (not_rounded) {

            c->lineto(sp_star_get_xy (star, SP_STAR_POINT_KNOT2, 0, true));

        } else {

            c->curveto(sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, 0, NEXT),

                sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT2, 0, PREV),

                sp_star_get_xy (star, SP_STAR_POINT_KNOT2, 0, true));

        }

    }

    // draw all middle segments

    for (gint i = 1; i < sides; i++) {

        if (not_rounded) {

            c->lineto(sp_star_get_xy (star, SP_STAR_POINT_KNOT1, i, true));

        } else {

            if (star->flatsided == false) {

                c->curveto(sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT2, i - 1, NEXT),

                        sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, i, PREV),

                        sp_star_get_xy (star, SP_STAR_POINT_KNOT1, i, true));

            } else {

                c->curveto(sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, i - 1, NEXT),

                        sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, i, PREV),

                        sp_star_get_xy (star, SP_STAR_POINT_KNOT1, i, true));

            }

        }

        if (star->flatsided == false) {

            if (not_rounded) {

                       c->lineto(sp_star_get_xy (star, SP_STAR_POINT_KNOT2, i, true));

            } else {

                c->curveto(sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, i, NEXT),

                    sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT2, i, PREV),

                    sp_star_get_xy (star, SP_STAR_POINT_KNOT2, i, true));

            }

        }

    }

    // draw last segment

        if (!not_rounded) {

            if (star->flatsided == false) {

            c->curveto(sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT2, sides - 1, NEXT),

                sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, 0, PREV),

                sp_star_get_xy (star, SP_STAR_POINT_KNOT1, 0, true));

            } else {

            c->curveto(sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, sides - 1, NEXT),

                sp_star_get_curvepoint (star, SP_STAR_POINT_KNOT1, 0, PREV),

                sp_star_get_xy (star, SP_STAR_POINT_KNOT1, 0, true));

            }

        }

    c->closepath();

    /* Reset the shape'scurve to the "original_curve"

     * This is very important for LPEs to work properly! (the bbox might be recalculated depending on the curve in shape)*/

    shape->setCurveInsync( c, TRUE);

    shape->setCurveBeforeLPE( c );

    if (sp_lpe_item_has_path_effect(SP_LPE_ITEM(shape)) && sp_lpe_item_path_effects_enabled(SP_LPE_ITEM(shape))) {

        SPCurve *c_lpe = c->copy();

        bool success = sp_lpe_item_perform_path_effect(SP_LPE_ITEM (shape), c_lpe);

        if (success) {

            shape->setCurveInsync( c_lpe, TRUE);

        } 

        c_lpe->unref();

    }

    c->unref();

}

void

sp_star_position_set (SPStar *star, gint sides, Geom::Point center, gdouble r1, gdouble r2, gdouble arg1, gdouble arg2, bool isflat, double rounded, double randomized)

{

    g_return_if_fail (star != NULL);

    g_return_if_fail (SP_IS_STAR (star));

    star->sides = CLAMP(sides, 3, 1024);

    star->center = center;

    star->r[0] = MAX (r1, 0.001);

    if (isflat == false) {

        star->r[1] = CLAMP(r2, 0.0, star->r[0]);

    } else {

        star->r[1] = CLAMP( r1*cos(M_PI/sides) ,0.0, star->r[0] );

    }

    star->arg[0] = arg1;

    star->arg[1] = arg2;

    star->flatsided = isflat;

    star->rounded = rounded;

    star->randomized = randomized;

    star->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);

}

static void sp_star_snappoints(SPItem const *item, std::vector<Inkscape::SnapCandidatePoint> &p, Inkscape::SnapPreferences const *snapprefs)

{

    // We will determine the star's midpoint ourselves, instead of trusting on the base class

    // Therefore snapping to object midpoints is temporarily disabled

    Inkscape::SnapPreferences local_snapprefs = *snapprefs;

    local_snapprefs.setTargetSnappable(Inkscape::SNAPTARGET_OBJECT_MIDPOINT, false);

    if (((SPItemClass *) parent_class)->snappoints) {

        ((SPItemClass *) parent_class)->snappoints (item, p, &local_snapprefs);

    }

    if (snapprefs->isTargetSnappable(Inkscape::SNAPTARGET_OBJECT_MIDPOINT)) {

        Geom::Affine const i2dt (item->i2dt_affine ());

        p.push_back(Inkscape::SnapCandidatePoint(SP_STAR(item)->center * i2dt,Inkscape::SNAPSOURCE_OBJECT_MIDPOINT, Inkscape::SNAPTARGET_OBJECT_MIDPOINT));

    }

}

/**

 * sp_star_get_xy: Get X-Y value as item coordinate system

 * @star: star item

 * @point: point type to obtain X-Y value

 * @index: index of vertex

 * @p: pointer to store X-Y value

 * @randomized: false (default) if you want to get exact, not randomized point

 *

 * Initial item coordinate system is same as document coordinate system.

 */

Geom::Point

sp_star_get_xy (SPStar *star, SPStarPoint point, gint index, bool randomized)

{

    gdouble darg = 2.0 * M_PI / (double) star->sides;

    double arg = star->arg[point];

    arg += index * darg;

    Geom::Point xy = star->r[point] * Geom::Point(cos(arg), sin(arg)) + star->center;

    if (!randomized || star->randomized == 0) {

        // return the exact point

        return xy;

    } else { // randomize the point

        // find out the seed, unique for this point so that randomization is the same so long as the original point is stationary

        guint32 seed = point_unique_int (xy);

        // the full range (corresponding to star->randomized == 1.0) is equal to the star's diameter

        double range = 2 * MAX (star->r[0], star->r[1]);

        // find out the random displacement; x is controlled by step 1 from the seed, y by the step 2

        Geom::Point shift (star->randomized * range * rnd (seed, 1), star->randomized * range * rnd (seed, 2));

        // add the shift to the exact point

        return xy + shift;

    }

}

/*

  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 :