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-rw-r--r--src/object/sp-star.cpp569
1 files changed, 569 insertions, 0 deletions
diff --git a/src/object/sp-star.cpp b/src/object/sp-star.cpp
new file mode 100644
index 0000000..1e098a6
--- /dev/null
+++ b/src/object/sp-star.cpp
@@ -0,0 +1,569 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * <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 v2+, read the file 'COPYING' for more information.
+ */
+
+#include <cstring>
+#include <string>
+#include <glib.h>
+#include "live_effects/effect.h"
+
+#include "svg/svg.h"
+#include "attributes.h"
+#include "display/curve.h"
+#include "xml/repr.h"
+#include "document.h"
+
+#include "sp-star.h"
+#include <glibmm/i18n.h>
+
+SPStar::SPStar() : SPShape() ,
+ sides(5),
+ center(0, 0),
+ flatsided(false),
+ rounded(0.0),
+ randomized(0.0)
+{
+ this->r[0] = 1.0;
+ this->r[1] = 0.001;
+ this->arg[0] = this->arg[1] = 0.0;
+}
+
+SPStar::~SPStar() = default;
+
+void SPStar::build(SPDocument * document, Inkscape::XML::Node * repr) {
+ // CPPIFY: see header file
+ SPShape::build(document, repr);
+
+ this->readAttr(SPAttr::SODIPODI_CX);
+ this->readAttr(SPAttr::SODIPODI_CY);
+ this->readAttr(SPAttr::INKSCAPE_FLATSIDED);
+ this->readAttr(SPAttr::SODIPODI_SIDES);
+ this->readAttr(SPAttr::SODIPODI_R1);
+ this->readAttr(SPAttr::SODIPODI_R2);
+ this->readAttr(SPAttr::SODIPODI_ARG1);
+ this->readAttr(SPAttr::SODIPODI_ARG2);
+ this->readAttr(SPAttr::INKSCAPE_ROUNDED);
+ this->readAttr(SPAttr::INKSCAPE_RANDOMIZED);
+}
+
+Inkscape::XML::Node* SPStar::write(Inkscape::XML::Document *xml_doc, Inkscape::XML::Node *repr, guint flags) {
+ if ((flags & SP_OBJECT_WRITE_BUILD) && !repr) {
+ repr = xml_doc->createElement("svg:path");
+ }
+
+ if (flags & SP_OBJECT_WRITE_EXT) {
+ repr->setAttribute("sodipodi:type", "star");
+ repr->setAttributeBoolean("inkscape:flatsided", this->flatsided);
+ repr->setAttributeInt("sodipodi:sides", this->sides);
+ repr->setAttributeSvgDouble("sodipodi:cx", this->center[Geom::X]);
+ repr->setAttributeSvgDouble("sodipodi:cy", this->center[Geom::Y]);
+ repr->setAttributeSvgDouble("sodipodi:r1", this->r[0]);
+ repr->setAttributeSvgDouble("sodipodi:r2", this->r[1]);
+ repr->setAttributeSvgDouble("sodipodi:arg1", this->arg[0]);
+ repr->setAttributeSvgDouble("sodipodi:arg2", this->arg[1]);
+ repr->setAttributeSvgDouble("inkscape:rounded", this->rounded);
+ repr->setAttributeSvgDouble("inkscape:randomized", this->randomized);
+ }
+
+ this->set_shape();
+ if (this->_curve) {
+ repr->setAttribute("d", sp_svg_write_path(this->_curve->get_pathvector()));
+ } else {
+ repr->removeAttribute("d");
+ }
+ // CPPIFY: see header file
+ SPShape::write(xml_doc, repr, flags);
+
+ return repr;
+}
+
+void SPStar::set(SPAttr key, const gchar* value) {
+ SVGLength::Unit unit;
+
+ /* fixme: we should really collect updates */
+ switch (key) {
+ case SPAttr::SODIPODI_SIDES:
+ if (value) {
+ this->sides = atoi (value);
+ this->sides = CLAMP(this->sides, this->flatsided ? 3 : 2, 1024);
+ } else {
+ this->sides = 5;
+ }
+
+ this->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+ break;
+
+ case SPAttr::SODIPODI_CX:
+ if (!sp_svg_length_read_ldd (value, &unit, nullptr, &this->center[Geom::X]) ||
+ (unit == SVGLength::EM) ||
+ (unit == SVGLength::EX) ||
+ (unit == SVGLength::PERCENT)) {
+ this->center[Geom::X] = 0.0;
+ }
+
+ this->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+ break;
+
+ case SPAttr::SODIPODI_CY:
+ if (!sp_svg_length_read_ldd (value, &unit, nullptr, &this->center[Geom::Y]) ||
+ (unit == SVGLength::EM) ||
+ (unit == SVGLength::EX) ||
+ (unit == SVGLength::PERCENT)) {
+ this->center[Geom::Y] = 0.0;
+ }
+
+ this->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+ break;
+
+ case SPAttr::SODIPODI_R1:
+ if (!sp_svg_length_read_ldd (value, &unit, nullptr, &this->r[0]) ||
+ (unit == SVGLength::EM) ||
+ (unit == SVGLength::EX) ||
+ (unit == SVGLength::PERCENT)) {
+ this->r[0] = 1.0;
+ }
+
+ /* fixme: Need CLAMP (Lauris) */
+ this->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+ break;
+
+ case SPAttr::SODIPODI_R2:
+ if (!sp_svg_length_read_ldd (value, &unit, nullptr, &this->r[1]) ||
+ (unit == SVGLength::EM) ||
+ (unit == SVGLength::EX) ||
+ (unit == SVGLength::PERCENT)) {
+ this->r[1] = 0.0;
+ }
+
+ this->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+ return;
+
+ case SPAttr::SODIPODI_ARG1:
+ if (value) {
+ this->arg[0] = g_ascii_strtod (value, nullptr);
+ } else {
+ this->arg[0] = 0.0;
+ }
+
+ this->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+ break;
+
+ case SPAttr::SODIPODI_ARG2:
+ if (value) {
+ this->arg[1] = g_ascii_strtod (value, nullptr);
+ } else {
+ this->arg[1] = 0.0;
+ }
+
+ this->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+ break;
+
+ case SPAttr::INKSCAPE_FLATSIDED:
+ if (value && !strcmp(value, "true")) {
+ this->flatsided = true;
+ this->sides = MAX(this->sides, 3);
+ } else {
+ this->flatsided = false;
+ }
+
+ this->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+ break;
+
+ case SPAttr::INKSCAPE_ROUNDED:
+ if (value) {
+ this->rounded = g_ascii_strtod (value, nullptr);
+ } else {
+ this->rounded = 0.0;
+ }
+
+ this->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+ break;
+
+ case SPAttr::INKSCAPE_RANDOMIZED:
+ if (value) {
+ this->randomized = g_ascii_strtod (value, nullptr);
+ } else {
+ this->randomized = 0.0;
+ }
+
+ this->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+ break;
+
+ default:
+ // CPPIFY: see header file
+ SPShape::set(key, value);
+ break;
+ }
+}
+
+void SPStar::update(SPCtx *ctx, guint flags) {
+ if (flags & (SP_OBJECT_MODIFIED_FLAG |
+ SP_OBJECT_STYLE_MODIFIED_FLAG |
+ SP_OBJECT_VIEWPORT_MODIFIED_FLAG)) {
+
+ this->set_shape();
+ }
+
+ // CPPIFY: see header file
+ SPShape::update(ctx, flags);
+}
+
+const char* SPStar::typeName() const {
+ if (this->flatsided == false)
+ return "star";
+ return "polygon";
+}
+
+const char* SPStar::displayName() const {
+ if (this->flatsided == false)
+ return _("Star");
+ return _("Polygon");
+}
+
+gchar* SPStar::description() const {
+ // while there will never be less than 2 or 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.
+ return g_strdup_printf (ngettext(_("with %d vertex"), _("with %d vertices"),
+ this->sides), this->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
+
+void SPStar::set_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 (checkBrokenPathEffect()) {
+ return;
+ }
+
+ auto c = std::make_unique<SPCurve>();
+
+ bool not_rounded = (fabs (this->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 (this, SP_STAR_POINT_KNOT1, 0, true));
+
+ if (this->flatsided == false) {
+ if (not_rounded) {
+ c->lineto(sp_star_get_xy (this, SP_STAR_POINT_KNOT2, 0, true));
+ } else {
+ c->curveto(sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, 0, NEXT),
+ sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT2, 0, PREV),
+ sp_star_get_xy (this, 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 (this, SP_STAR_POINT_KNOT1, i, true));
+ } else {
+ if (this->flatsided == false) {
+ c->curveto(sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT2, i - 1, NEXT),
+ sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, i, PREV),
+ sp_star_get_xy (this, SP_STAR_POINT_KNOT1, i, true));
+ } else {
+ c->curveto(sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, i - 1, NEXT),
+ sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, i, PREV),
+ sp_star_get_xy (this, SP_STAR_POINT_KNOT1, i, true));
+ }
+ }
+
+ if (this->flatsided == false) {
+ if (not_rounded) {
+ c->lineto(sp_star_get_xy (this, SP_STAR_POINT_KNOT2, i, true));
+ } else {
+ c->curveto(sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, i, NEXT),
+ sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT2, i, PREV),
+ sp_star_get_xy (this, SP_STAR_POINT_KNOT2, i, true));
+ }
+ }
+ }
+
+ // draw last segment
+ if (!not_rounded) {
+ if (this->flatsided == false) {
+ c->curveto(sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT2, sides - 1, NEXT),
+ sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, 0, PREV),
+ sp_star_get_xy (this, SP_STAR_POINT_KNOT1, 0, true));
+ } else {
+ c->curveto(sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, sides - 1, NEXT),
+ sp_star_get_curvepoint (this, SP_STAR_POINT_KNOT1, 0, PREV),
+ sp_star_get_xy (this, SP_STAR_POINT_KNOT1, 0, true));
+ }
+ }
+
+ c->closepath();
+
+ if (prepareShapeForLPE(c.get())) {
+ return;
+ }
+
+ // This happends on undo, fix bug:#1791784
+ setCurveInsync(std::move(c));
+}
+
+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 != nullptr);
+ g_return_if_fail (SP_IS_STAR (star));
+
+ star->flatsided = isflat;
+ star->center = center;
+ star->r[0] = MAX (r1, 0.001);
+
+ if (isflat == false) {
+ star->sides = CLAMP(sides, 2, 1024);
+ star->r[1] = CLAMP(r2, 0.0, star->r[0]);
+ } else {
+ star->sides = CLAMP(sides, 3, 1024);
+ star->r[1] = CLAMP( r1*cos(M_PI/sides) ,0.0, star->r[0] );
+ }
+
+ star->arg[0] = arg1;
+ star->arg[1] = arg2;
+ star->rounded = rounded;
+ star->randomized = randomized;
+ star->requestDisplayUpdate(SP_OBJECT_MODIFIED_FLAG);
+}
+
+void SPStar::snappoints(std::vector<Inkscape::SnapCandidatePoint> &p, Inkscape::SnapPreferences const *snapprefs) const {
+ // 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);
+
+ // CPPIFY: see header file
+ SPShape::snappoints(p, &local_snapprefs);
+
+ if (snapprefs->isTargetSnappable(Inkscape::SNAPTARGET_OBJECT_MIDPOINT)) {
+ Geom::Affine const i2dt (this->i2dt_affine ());
+ p.emplace_back(this->center * i2dt,Inkscape::SNAPSOURCE_OBJECT_MIDPOINT, Inkscape::SNAPTARGET_OBJECT_MIDPOINT);
+ }
+}
+
+Geom::Affine SPStar::set_transform(Geom::Affine const &xform)
+{
+ bool opt_trans = (randomized == 0);
+ if (pathEffectsEnabled() && !optimizeTransforms()) {
+ return xform;
+ }
+ // Only set transform with proportional scaling
+ if (!xform.withoutTranslation().isUniformScale()) {
+ return xform;
+ }
+
+ /* Calculate star start in parent coords. */
+ Geom::Point pos( this->center * xform );
+
+ /* This function takes care of translation and scaling, we return whatever parts we can't
+ handle. */
+ Geom::Affine ret(opt_trans ? xform.withoutTranslation() : xform);
+ gdouble const s = hypot(ret[0], ret[1]);
+ if (s > 1e-9) {
+ ret[0] /= s;
+ ret[1] /= s;
+ ret[2] /= s;
+ ret[3] /= s;
+ } else {
+ ret[0] = 1.0;
+ ret[1] = 0.0;
+ ret[2] = 0.0;
+ ret[3] = 1.0;
+ }
+
+ this->r[0] *= s;
+ this->r[1] *= s;
+
+ /* Find start in item coords */
+ pos = pos * ret.inverse();
+ this->center = pos;
+
+ this->set_shape();
+
+ // Adjust stroke width
+ this->adjust_stroke(s);
+
+ // Adjust pattern fill
+ this->adjust_pattern(xform * ret.inverse());
+
+ // Adjust gradient fill
+ this->adjust_gradient(xform * ret.inverse());
+
+ return ret;
+}
+
+void SPStar::update_patheffect(bool write) {
+ SPShape::update_patheffect(write);
+}
+
+/**
+ * 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 const *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 :