#define noERASER_VERBOSE

#include "config.h"

#include <gtk/gtk.h>

#include <gdk/gdkkeysyms.h>

#include <glibmm/i18n.h>

#include <string>

#include <cstring>

#include <numeric>

#include "svg/svg.h"

#include "display/sp-canvas.h"

#include "display/canvas-bpath.h"

#include <2geom/bezier-utils.h>

#include <glib.h>

#include "macros.h"

#include "document.h"

#include "selection.h"

#include "desktop.h"

#include "desktop-events.h"

#include "desktop-style.h"

#include "message-context.h"

#include "preferences.h"

#include "pixmaps/cursor-eraser.xpm"

#include "xml/repr.h"

#include "context-fns.h"

#include "sp-item.h"

#include "color.h"

#include "rubberband.h"

#include "splivarot.h"

#include "sp-item-group.h"

#include "sp-shape.h"

#include "sp-path.h"

#include "sp-text.h"

#include "display/canvas-bpath.h"

#include "display/canvas-arena.h"

#include "livarot/Shape.h"

#include "document-undo.h"

#include "verbs.h"

#include <2geom/math-utils.h>

#include <2geom/pathvector.h>

#include "display/curve.h"

#include "ui/tools/eraser-tool.h"

using Inkscape::DocumentUndo;

#define ERC_RED_RGBA 0xff0000ff

#define TOLERANCE_ERASER 0.1

#define ERASER_EPSILON 0.5e-6

#define ERASER_EPSILON_START 0.5e-2

#define ERASER_VEL_START 1e-5

#define DRAG_MIN 0.0

#define DRAG_DEFAULT 1.0

#define DRAG_MAX 1.0

namespace Inkscape {

namespace UI {

namespace Tools {

const std::string& EraserTool::getPrefsPath() {

return EraserTool::prefsPath;

}

const std::string EraserTool::prefsPath = "/tools/eraser";

EraserTool::EraserTool()

: DynamicBase(cursor_eraser_xpm, 4, 4)

{

}

EraserTool::~EraserTool() {

}

void EraserTool::setup() {

DynamicBase::setup();

this->accumulated = new SPCurve();

this->currentcurve = new SPCurve();

this->cal1 = new SPCurve();

this->cal2 = new SPCurve();

this->currentshape = sp_canvas_item_new(desktop->getSketch(), SP_TYPE_CANVAS_BPATH, NULL);

sp_canvas_bpath_set_fill(SP_CANVAS_BPATH(this->currentshape), ERC_RED_RGBA, SP_WIND_RULE_EVENODD);

sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(this->currentshape), 0x00000000, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);

/* fixme: Cannot we cascade it to root more clearly? */

g_signal_connect(G_OBJECT(this->currentshape), "event", G_CALLBACK(sp_desktop_root_handler), desktop);

sp_event_context_read(this, "mass");

sp_event_context_read(this, "wiggle");

sp_event_context_read(this, "angle");

sp_event_context_read(this, "width");

sp_event_context_read(this, "thinning");

sp_event_context_read(this, "tremor");

sp_event_context_read(this, "flatness");

sp_event_context_read(this, "tracebackground");

sp_event_context_read(this, "usepressure");

sp_event_context_read(this, "usetilt");

sp_event_context_read(this, "abs_width");

sp_event_context_read(this, "cap_rounding");

this->is_drawing = false;

Inkscape::Preferences *prefs = Inkscape::Preferences::get();

if (prefs->getBool("/tools/eraser/selcue", 0) != 0) {

this->enableSelectionCue();

}

// TODO temp force:

this->enableSelectionCue();

}

static double

flerp(double f0, double f1, double p)

{

return f0 + ( f1 - f0 ) * p;

}

void EraserTool::reset(Geom::Point p) {

this->last = this->cur = getNormalizedPoint(p);

this->vel = Geom::Point(0,0);

this->vel_max = 0;

this->acc = Geom::Point(0,0);

this->ang = Geom::Point(0,0);

this->del = Geom::Point(0,0);

}

void EraserTool::extinput(GdkEvent *event) {

if (gdk_event_get_axis (event, GDK_AXIS_PRESSURE, &this->pressure))

this->pressure = CLAMP (this->pressure, ERC_MIN_PRESSURE, ERC_MAX_PRESSURE);

else

this->pressure = ERC_DEFAULT_PRESSURE;

if (gdk_event_get_axis (event, GDK_AXIS_XTILT, &this->xtilt))

this->xtilt = CLAMP (this->xtilt, ERC_MIN_TILT, ERC_MAX_TILT);

else

this->xtilt = ERC_DEFAULT_TILT;

if (gdk_event_get_axis (event, GDK_AXIS_YTILT, &this->ytilt))

this->ytilt = CLAMP (this->ytilt, ERC_MIN_TILT, ERC_MAX_TILT);

else

this->ytilt = ERC_DEFAULT_TILT;

}

bool EraserTool::apply(Geom::Point p) {

Geom::Point n = getNormalizedPoint(p);

/* Calculate mass and drag */

double const mass = flerp(1.0, 160.0, this->mass);

double const drag = flerp(0.0, 0.5, this->drag * this->drag);

/* Calculate force and acceleration */

Geom::Point force = n - this->cur;

// If force is below the absolute threshold ERASER_EPSILON,

// or we haven't yet reached ERASER_VEL_START (i.e. at the beginning of stroke)

// _and_ the force is below the (higher) ERASER_EPSILON_START threshold,

// discard this move.

// This prevents flips, blobs, and jerks caused by microscopic tremor of the tablet pen,

// especially bothersome at the start of the stroke where we don't yet have the inertia to

// smooth them out.

if ( Geom::L2(force) < ERASER_EPSILON || (this->vel_max < ERASER_VEL_START && Geom::L2(force) < ERASER_EPSILON_START)) {

return FALSE;

}

this->acc = force / mass;

/* Calculate new velocity */

this->vel += this->acc;

if (Geom::L2(this->vel) > this->vel_max)

this->vel_max = Geom::L2(this->vel);

/* Calculate angle of drawing tool */

double a1;

if (this->usetilt) {

// 1a. calculate nib angle from input device tilt:

gdouble length = std::sqrt(this->xtilt*this->xtilt + this->ytilt*this->ytilt);;

if (length > 0) {

Geom::Point ang1 = Geom::Point(this->ytilt/length, this->xtilt/length);

a1 = atan2(ang1);

}

else

a1 = 0.0;

}

else {

// 1b. fixed dc->angle (absolutely flat nib):

double const radians = ( (this->angle - 90) / 180.0 ) * M_PI;

Geom::Point ang1 = Geom::Point(-sin(radians), cos(radians));

a1 = atan2(ang1);

}

// 2. perpendicular to dc->vel (absolutely non-flat nib):

gdouble const mag_vel = Geom::L2(this->vel);

if ( mag_vel < ERASER_EPSILON ) {

return FALSE;

}

Geom::Point ang2 = Geom::rot90(this->vel) / mag_vel;

// 3. Average them using flatness parameter:

// calculate angles

double a2 = atan2(ang2);

// flip a2 to force it to be in the same half-circle as a1

bool flipped = false;

if (fabs (a2-a1) > 0.5*M_PI) {

a2 += M_PI;

flipped = true;

}

// normalize a2

if (a2 > M_PI)

a2 -= 2*M_PI;

if (a2 < -M_PI)

a2 += 2*M_PI;

// find the flatness-weighted bisector angle, unflip if a2 was flipped

// FIXME: when dc->vel is oscillating around the fixed angle, the new_ang flips back and forth. How to avoid this?

double new_ang = a1 + (1 - this->flatness) * (a2 - a1) - (flipped? M_PI : 0);

// Try to detect a sudden flip when the new angle differs too much from the previous for the

// current velocity; in that case discard this move

double angle_delta = Geom::L2(Geom::Point (cos (new_ang), sin (new_ang)) - this->ang);

if ( angle_delta / Geom::L2(this->vel) > 4000 ) {

return FALSE;

}

// convert to point

this->ang = Geom::Point (cos (new_ang), sin (new_ang));

/* Apply drag */

this->vel *= 1.0 - drag;

/* Update position */

this->last = this->cur;

this->cur += this->vel;

return TRUE;

}

void EraserTool::brush() {

g_assert( this->npoints >= 0 && this->npoints < SAMPLING_SIZE );

// How much velocity thins strokestyle

double vel_thin = flerp (0, 160, this->vel_thin);

// Influence of pressure on thickness

double pressure_thick = (this->usepressure ? this->pressure : 1.0);

// get the real brush point, not the same as pointer (affected by hatch tracking and/or mass

// drag)

Geom::Point brush = getViewPoint(this->cur);

//Geom::Point brush_w = SP_EVENT_CONTEXT(dc)->desktop->d2w(brush);

double trace_thick = 1;

double width = (pressure_thick * trace_thick - vel_thin * Geom::L2(this->vel)) * this->width;

double tremble_left = 0, tremble_right = 0;

if (this->tremor > 0) {

// obtain two normally distributed random variables, using polar Box-Muller transform

double x1, x2, w, y1, y2;

do {

x1 = 2.0 * g_random_double_range(0,1) - 1.0;

x2 = 2.0 * g_random_double_range(0,1) - 1.0;

w = x1 * x1 + x2 * x2;

} while ( w >= 1.0 );

w = sqrt( (-2.0 * log( w ) ) / w );

y1 = x1 * w;

y2 = x2 * w;

// deflect both left and right edges randomly and independently, so that:

// (1) dc->tremor=1 corresponds to sigma=1, decreasing dc->tremor narrows the bell curve;

// (2) deflection depends on width, but is upped for small widths for better visual uniformity across widths;

// (3) deflection somewhat depends on speed, to prevent fast strokes looking

// comparatively smooth and slow ones excessively jittery

tremble_left = (y1)*this->tremor * (0.15 + 0.8*width) * (0.35 + 14*Geom::L2(this->vel));

tremble_right = (y2)*this->tremor * (0.15 + 0.8*width) * (0.35 + 14*Geom::L2(this->vel));

}

if ( width < 0.02 * this->width ) {

width = 0.02 * this->width;

}

double dezoomify_factor = 0.05 * 1000;

if (!this->abs_width) {

dezoomify_factor /= SP_EVENT_CONTEXT(this)->desktop->current_zoom();

}

Geom::Point del_left = dezoomify_factor * (width + tremble_left) * this->ang;

Geom::Point del_right = dezoomify_factor * (width + tremble_right) * this->ang;

this->point1[this->npoints] = brush + del_left;

this->point2[this->npoints] = brush - del_right;

this->del = 0.5*(del_left + del_right);

this->npoints++;

}

static void

sp_erc_update_toolbox (SPDesktop *desktop, const gchar *id, double value)

{

desktop->setToolboxAdjustmentValue (id, value);

}

void EraserTool::cancel() {

SPDesktop *desktop = SP_EVENT_CONTEXT(this)->desktop;

this->dragging = FALSE;

this->is_drawing = false;

sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate), 0);

/* Remove all temporary line segments */

while (this->segments) {

sp_canvas_item_destroy(SP_CANVAS_ITEM(this->segments->data));

this->segments = g_slist_remove(this->segments, this->segments->data);

}

/* reset accumulated curve */

this->accumulated->reset();

this->clear_current();

if (this->repr) {

this->repr = NULL;

}

}

bool EraserTool::root_handler(GdkEvent* event) {

gint ret = FALSE;

switch (event->type) {

case GDK_BUTTON_PRESS:

if (event->button.button == 1 && !this->space_panning) {

if (Inkscape::have_viable_layer(desktop, this->message_context) == false) {

return TRUE;

}

Geom::Point const button_w(event->button.x, event->button.y);

Geom::Point const button_dt(desktop->w2d(button_w));

this->reset(button_dt);

this->extinput(event);

this->apply(button_dt);

this->accumulated->reset();

if (this->repr) {

this->repr = NULL;

}

Inkscape::Rubberband::get(desktop)->start(desktop, button_dt);

Inkscape::Rubberband::get(desktop)->setMode(RUBBERBAND_MODE_TOUCHPATH);

/* initialize first point */

this->npoints = 0;

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;

desktop->canvas->forceFullRedrawAfterInterruptions(3);

this->is_drawing = true;

}

break;

case GDK_MOTION_NOTIFY: {

Geom::Point const motion_w(event->motion.x, event->motion.y);

Geom::Point motion_dt(desktop->w2d(motion_w)

);

this->extinput(event);

this->message_context->clear();

if ( this->is_drawing && (event->motion.state & GDK_BUTTON1_MASK) && !this->space_panning) {

this->dragging = TRUE;

this->message_context->set(Inkscape::NORMAL_MESSAGE, _("<b>Drawing</b> an eraser stroke"));

if (!this->apply(motion_dt)) {

ret = TRUE;

break;

}

if ( this->cur != this->last ) {

this->brush();

g_assert( this->npoints > 0 );

this->fit_and_split(false);

}

ret = TRUE;

}

Inkscape::Rubberband::get(desktop)->move(motion_dt);

}

break;

case GDK_BUTTON_RELEASE: {

Geom::Point const motion_w(event->button.x, event->button.y);

Geom::Point const motion_dt(desktop->w2d(motion_w));

sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate), event->button.time);

desktop->canvas->endForcedFullRedraws();

this->is_drawing = false;

if (this->dragging && event->button.button == 1 && !this->space_panning) {

this->dragging = FALSE;

this->apply(motion_dt);

/* Remove all temporary line segments */

while (this->segments) {

sp_canvas_item_destroy(SP_CANVAS_ITEM(this->segments->data));

this->segments = g_slist_remove(this->segments, this->segments->data);

}

/* Create object */

this->fit_and_split(true);

this->accumulate();

this->set_to_accumulated(); // performs document_done

/* reset accumulated curve */

this->accumulated->reset();

this->clear_current();

if (this->repr) {

this->repr = NULL;

}

this->message_context->clear();

ret = TRUE;

}

if (Inkscape::Rubberband::get(desktop)->is_started()) {

Inkscape::Rubberband::get(desktop)->stop();

}

break;

}

case GDK_KEY_PRESS:

switch (get_group0_keyval (&event->key)) {

case GDK_KEY_Up:

case GDK_KEY_KP_Up:

if (!MOD__CTRL_ONLY(event)) {

this->angle += 5.0;

if (this->angle > 90.0) {

this->angle = 90.0;

}

sp_erc_update_toolbox (desktop, "eraser-angle", this->angle);

ret = TRUE;

}

break;

case GDK_KEY_Down:

case GDK_KEY_KP_Down:

if (!MOD__CTRL_ONLY(event)) {

this->angle -= 5.0;

if (this->angle < -90.0) {

this->angle = -90.0;

}

sp_erc_update_toolbox (desktop, "eraser-angle", this->angle);

ret = TRUE;

}

break;

case GDK_KEY_Right:

case GDK_KEY_KP_Right:

if (!MOD__CTRL_ONLY(event)) {

this->width += 0.01;

if (this->width > 1.0) {

this->width = 1.0;

}

sp_erc_update_toolbox (desktop, "altx-eraser", this->width * 100); // the same spinbutton is for alt+x

ret = TRUE;

}

break;

case GDK_KEY_Left:

case GDK_KEY_KP_Left:

if (!MOD__CTRL_ONLY(event)) {

this->width -= 0.01;

if (this->width < 0.01) {

this->width = 0.01;

}

sp_erc_update_toolbox (desktop, "altx-eraser", this->width * 100);

ret = TRUE;

}

break;

case GDK_KEY_Home:

case GDK_KEY_KP_Home:

this->width = 0.01;

sp_erc_update_toolbox (desktop, "altx-eraser", this->width * 100);

ret = TRUE;

break;

case GDK_KEY_End:

case GDK_KEY_KP_End:

this->width = 1.0;

sp_erc_update_toolbox (desktop, "altx-eraser", this->width * 100);

ret = TRUE;

break;

case GDK_KEY_x:

case GDK_KEY_X:

if (MOD__ALT_ONLY(event)) {

desktop->setToolboxFocusTo ("altx-eraser");

ret = TRUE;

}

break;

case GDK_KEY_Escape:

Inkscape::Rubberband::get(desktop)->stop();

if (this->is_drawing) {

// if drawing, cancel, otherwise pass it up for deselecting

this->cancel();

ret = TRUE;

}

break;

case GDK_KEY_z:

case GDK_KEY_Z:

if (MOD__CTRL_ONLY(event) && this->is_drawing) {

// if drawing, cancel, otherwise pass it up for undo

this->cancel();

ret = TRUE;

}

break;

default:

break;

}

break;

case GDK_KEY_RELEASE:

switch (get_group0_keyval(&event->key)) {

case GDK_KEY_Control_L:

case GDK_KEY_Control_R:

this->message_context->clear();

break;

default:

break;

}

break;

default:

break;

}

if (!ret) {

ret = DynamicBase::root_handler(event);

}

return ret;

}

void EraserTool::clear_current() {

// reset bpath

sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(this->currentshape), NULL);

// reset curve

this->currentcurve->reset();

this->cal1->reset();

this->cal2->reset();

// reset points

this->npoints = 0;

}

void EraserTool::set_to_accumulated() {

bool workDone = false;

if (!this->accumulated->is_empty()) {

if (!this->repr) {

/* Create object */

Inkscape::XML::Document *xml_doc = desktop->doc()->getReprDoc();

Inkscape::XML::Node *repr = xml_doc->createElement("svg:path");

/* Set style */

sp_desktop_apply_style_tool (desktop, repr, "/tools/eraser", false);

this->repr = repr;

SPItem *item=SP_ITEM(desktop->currentLayer()->appendChildRepr(this->repr));

Inkscape::GC::release(this->repr);

item->transform = SP_ITEM(desktop->currentLayer())->i2doc_affine().inverse();

item->updateRepr();

}

Geom::PathVector pathv = this->accumulated->get_pathvector() * desktop->dt2doc();

gchar *str = sp_svg_write_path(pathv);

g_assert( str != NULL );

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

g_free(str);

if ( this->repr ) {

bool wasSelection = false;

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

Inkscape::Preferences *prefs = Inkscape::Preferences::get();

gint eraserMode = prefs->getBool("/tools/eraser/mode") ? 1 : 0;

Inkscape::XML::Document *xml_doc = desktop->doc()->getReprDoc();

SPItem* acid = SP_ITEM(desktop->doc()->getObjectByRepr(this->repr));

Geom::OptRect eraserBbox = acid->visualBounds();

Geom::Rect bounds = (*eraserBbox) * desktop->doc2dt();

std::vector<SPItem*> remainingItems;

std::vector<SPItem*> toWorkOn;

if (selection->isEmpty()) {

if ( eraserMode ) {

toWorkOn = desktop->getDocument()->getItemsPartiallyInBox(desktop->dkey, bounds);

} else {

Inkscape::Rubberband *r = Inkscape::Rubberband::get(desktop);

toWorkOn = desktop->getDocument()->getItemsAtPoints(desktop->dkey, r->getPoints());

}

toWorkOn.erase(std::remove(toWorkOn.begin(), toWorkOn.end(), acid), toWorkOn.end());

} else {

toWorkOn= selection->itemList();

wasSelection = true;

}

if ( !toWorkOn.empty() ) {

if ( eraserMode ) {

for (std::vector<SPItem*>::const_iterator i = toWorkOn.begin(); i != toWorkOn.end(); i++){

SPItem *item = *i;

if ( eraserMode ) {

Geom::OptRect bbox = item->visualBounds();

if (bbox && bbox->intersects(*eraserBbox)) {

Inkscape::XML::Node* dup = this->repr->duplicate(xml_doc);

this->repr->parent()->appendChild(dup);

Inkscape::GC::release(dup); // parent takes over

selection->set(item);

selection->add(dup);

sp_selected_path_diff_skip_undo(selection, desktop);

workDone = true; // TODO set this only if something was cut.

if ( !selection->isEmpty() ) {

// If the item was not completely erased, track the new remainder.

std::vector<SPItem*> nowSel(selection->itemList());

for (std::vector<SPItem*>::const_iterator i2 = nowSel.begin();i2!=nowSel.end();i2++) {

remainingItems.push_back(*i2);

}

}

} else {

remainingItems.push_back(item);

}

}

}

} else {

for (std::vector<SPItem*> ::const_iterator i = toWorkOn.begin();i!=toWorkOn.end();i++) {

sp_object_ref( *i, 0 );

}

for (std::vector<SPItem*>::const_iterator i = toWorkOn.begin();i!=toWorkOn.end();i++) {

SPItem *item = *i;

item->deleteObject(true);

sp_object_unref(item);

workDone = true;

}

}

if ( !eraserMode ) {

//sp_selection_delete(desktop);

remainingItems.clear();

}

selection->clear();

if ( wasSelection ) {

if ( !remainingItems.empty() ) {

selection->add(remainingItems.begin(), remainingItems.end());

}

}

}

// Remove the eraser stroke itself:

sp_repr_unparent( this->repr );

this->repr = 0;

}

} else {

if (this->repr) {

sp_repr_unparent(this->repr);

this->repr = 0;

}

}

if ( workDone ) {

DocumentUndo::done(desktop->getDocument(), SP_VERB_CONTEXT_ERASER, _("Draw eraser stroke"));

} else {

DocumentUndo::cancel(desktop->getDocument());

}

}

static void

add_cap(SPCurve *curve,

Geom::Point const &pre, Geom::Point const &from,

Geom::Point const &to, Geom::Point const &post,

double rounding)

{

Geom::Point vel = rounding * Geom::rot90( to - from ) / sqrt(2.0);

double mag = Geom::L2(vel);

Geom::Point v_in = from - pre;

double mag_in = Geom::L2(v_in);

if ( mag_in > ERASER_EPSILON ) {

v_in = mag * v_in / mag_in;

} else {

v_in = Geom::Point(0, 0);

}

Geom::Point v_out = to - post;

double mag_out = Geom::L2(v_out);

if ( mag_out > ERASER_EPSILON ) {

v_out = mag * v_out / mag_out;

} else {

v_out = Geom::Point(0, 0);

}

if ( Geom::L2(v_in) > ERASER_EPSILON || Geom::L2(v_out) > ERASER_EPSILON ) {

curve->curveto(from + v_in, to + v_out, to);

}

}

void EraserTool::accumulate() {

if ( !this->cal1->is_empty() && !this->cal2->is_empty() ) {

this->accumulated->reset(); /* Is this required ?? */

SPCurve *rev_cal2 = this->cal2->create_reverse();

g_assert(this->cal1->get_segment_count() > 0);

g_assert(rev_cal2->get_segment_count() > 0);

g_assert( ! this->cal1->first_path()->closed() );

g_assert( ! rev_cal2->first_path()->closed() );

Geom::CubicBezier const * dc_cal1_firstseg = dynamic_cast<Geom::CubicBezier const *>( this->cal1->first_segment() );

Geom::CubicBezier const * rev_cal2_firstseg = dynamic_cast<Geom::CubicBezier const *>( rev_cal2->first_segment() );

Geom::CubicBezier const * dc_cal1_lastseg = dynamic_cast<Geom::CubicBezier const *>( this->cal1->last_segment() );

Geom::CubicBezier const * rev_cal2_lastseg = dynamic_cast<Geom::CubicBezier const *>( rev_cal2->last_segment() );

g_assert( dc_cal1_firstseg );

g_assert( rev_cal2_firstseg );

g_assert( dc_cal1_lastseg );

g_assert( rev_cal2_lastseg );

this->accumulated->append(this->cal1, FALSE);

add_cap(this->accumulated, (*dc_cal1_lastseg)[2], (*dc_cal1_lastseg)[3], (*rev_cal2_firstseg)[0], (*rev_cal2_firstseg)[1], this->cap_rounding);

this->accumulated->append(rev_cal2, TRUE);

add_cap(this->accumulated, (*rev_cal2_lastseg)[2], (*rev_cal2_lastseg)[3], (*dc_cal1_firstseg)[0], (*dc_cal1_firstseg)[1], this->cap_rounding);

this->accumulated->closepath();

rev_cal2->unref();

this->cal1->reset();

this->cal2->reset();

}

}

static double square(double const x)

{

return x * x;

}

void EraserTool::fit_and_split(bool release) {

double const tolerance_sq = square( desktop->w2d().descrim() * TOLERANCE_ERASER );

#ifdef ERASER_VERBOSE

g_print("[F&S:R=%c]", release?'T':'F');

#endif

if (!( this->npoints > 0 && this->npoints < SAMPLING_SIZE ))

return; // just clicked

if ( this->npoints == SAMPLING_SIZE - 1 || release ) {

#define BEZIER_SIZE 4

#define BEZIER_MAX_BEZIERS 8

#define BEZIER_MAX_LENGTH ( BEZIER_SIZE * BEZIER_MAX_BEZIERS )

#ifdef ERASER_VERBOSE

g_print("[F&S:#] this->npoints:%d, release:%s\n",

dc->npoints, release ? "TRUE" : "FALSE");

#endif

/* Current eraser */

if ( this->cal1->is_empty() || this->cal2->is_empty() ) {

/* dc->npoints > 0 */

/* g_print("erasers(1|2) reset\n"); */

this->cal1->reset();

this->cal2->reset();

this->cal1->moveto(this->point1[0]);

this->cal2->moveto(this->point2[0]);

}

Geom::Point b1[BEZIER_MAX_LENGTH];

gint const nb1 = Geom::bezier_fit_cubic_r(b1, this->point1, this->npoints, tolerance_sq, BEZIER_MAX_BEZIERS);

g_assert( nb1 * BEZIER_SIZE <= gint(G_N_ELEMENTS(b1)) );

Geom::Point b2[BEZIER_MAX_LENGTH];

gint const nb2 = Geom::bezier_fit_cubic_r(b2, this->point2, this->npoints, tolerance_sq, BEZIER_MAX_BEZIERS);

g_assert( nb2 * BEZIER_SIZE <= gint(G_N_ELEMENTS(b2)) );

if ( nb1 != -1 && nb2 != -1 ) {

/* Fit and draw and reset state */

#ifdef ERASER_VERBOSE

g_print("nb1:%d nb2:%d\n", nb1, nb2);

#endif

/* CanvasShape */

if (! release) {

this->currentcurve->reset();

this->currentcurve->moveto(b1[0]);

for (Geom::Point *bp1 = b1; bp1 < b1 + BEZIER_SIZE * nb1; bp1 += BEZIER_SIZE) {

this->currentcurve->curveto(bp1[1], bp1[2], bp1[3]);

}

this->currentcurve->lineto(b2[BEZIER_SIZE*(nb2-1) + 3]);

for (Geom::Point *bp2 = b2 + BEZIER_SIZE * ( nb2 - 1 ); bp2 >= b2; bp2 -= BEZIER_SIZE) {

this->currentcurve->curveto(bp2[2], bp2[1], bp2[0]);

}

// FIXME: this->segments is always NULL at this point??

if (!this->segments) { // first segment

add_cap(this->currentcurve, b2[1], b2[0], b1[0], b1[1], this->cap_rounding);

}

this->currentcurve->closepath();

sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(this->currentshape), this->currentcurve);

}

/* Current eraser */

for (Geom::Point *bp1 = b1; bp1 < b1 + BEZIER_SIZE * nb1; bp1 += BEZIER_SIZE) {

this->cal1->curveto(bp1[1], bp1[2], bp1[3]);

}

for (Geom::Point *bp2 = b2; bp2 < b2 + BEZIER_SIZE * nb2; bp2 += BEZIER_SIZE) {

this->cal2->curveto(bp2[1], bp2[2], bp2[3]);

}

} else {

/* fixme: ??? */

#ifdef ERASER_VERBOSE

g_print("[fit_and_split] failed to fit-cubic.\n");

#endif

this->draw_temporary_box();

for (gint i = 1; i < this->npoints; i++) {

this->cal1->lineto(this->point1[i]);

}

for (gint i = 1; i < this->npoints; i++) {

this->cal2->lineto(this->point2[i]);

}

}

/* Fit and draw and copy last point */

#ifdef ERASER_VERBOSE

g_print("[%d]Yup\n", this->npoints);

#endif

if (!release) {

Inkscape::Preferences *prefs = Inkscape::Preferences::get();

gint eraserMode = prefs->getBool("/tools/eraser/mode") ? 1 : 0;

g_assert(!this->currentcurve->is_empty());

SPCanvasItem *cbp = sp_canvas_item_new(desktop->getSketch(), SP_TYPE_CANVAS_BPATH, NULL);

SPCurve *curve = this->currentcurve->copy();

sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH (cbp), curve);

curve->unref();

guint32 fillColor = sp_desktop_get_color_tool (desktop, "/tools/eraser", true);

//guint32 strokeColor = sp_desktop_get_color_tool (desktop, "/tools/eraser", false);

double opacity = sp_desktop_get_master_opacity_tool (desktop, "/tools/eraser");

double fillOpacity = sp_desktop_get_opacity_tool (desktop, "/tools/eraser", true);

//double strokeOpacity = sp_desktop_get_opacity_tool (desktop, "/tools/eraser", false);

sp_canvas_bpath_set_fill(SP_CANVAS_BPATH(cbp), ((fillColor & 0xffffff00) | SP_COLOR_F_TO_U(opacity*fillOpacity)), SP_WIND_RULE_EVENODD);

//on second thougtht don't do stroke yet because we don't have stoke-width yet and because stoke appears between segments while drawing

//sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(cbp), ((strokeColor & 0xffffff00) | SP_COLOR_F_TO_U(opacity*strokeOpacity)), 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);

sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(cbp), 0x00000000, 1.0, SP_STROKE_LINEJOIN_MITER, SP_STROKE_LINECAP_BUTT);

/* fixme: Cannot we cascade it to root more clearly? */

g_signal_connect(G_OBJECT(cbp), "event", G_CALLBACK(sp_desktop_root_handler), desktop);

this->segments = g_slist_prepend(this->segments, cbp);

if ( !eraserMode ) {

sp_canvas_item_hide(cbp);

sp_canvas_item_hide(this->currentshape);

}

}

this->point1[0] = this->point1[this->npoints - 1];

this->point2[0] = this->point2[this->npoints - 1];

this->npoints = 1;

} else {

this->draw_temporary_box();

}

}

void EraserTool::draw_temporary_box() {

this->currentcurve->reset();

this->currentcurve->moveto(this->point1[this->npoints-1]);

for (gint i = this->npoints-2; i >= 0; i--) {

this->currentcurve->lineto(this->point1[i]);

}

for (gint i = 0; i < this->npoints; i++) {

this->currentcurve->lineto(this->point2[i]);

}

if (this->npoints >= 2) {

add_cap(this->currentcurve, this->point2[this->npoints-2], this->point2[this->npoints-1], this->point1[this->npoints-1], this->point1[this->npoints-2], this->cap_rounding);

}

this->currentcurve->closepath();

sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(this->currentshape), this->currentcurve);

}

}

}

}