Added missing eraser files

diff --git a/src/eraser-context.cpp b/src/eraser-context.cpp
new file mode 100644 (file)
index 0000000..f874855
--- /dev/null
+++ b/src/eraser-context.cpp
@@ -0,0 +1,1101 @@
+/*
+ * Eraser drawing mode
+ *
+ * Authors:
+ *   Mitsuru Oka <oka326@parkcity.ne.jp>
+ *   Lauris Kaplinski <lauris@kaplinski.com>
+ *   bulia byak <buliabyak@users.sf.net>
+ *   MenTaLguY <mental@rydia.net>
+ *   Jon A. Cruz <jon@joncruz.org>
+ *
+ * The original dynadraw code:
+ *   Paul Haeberli <paul@sgi.com>
+ *
+ * Copyright (C) 1998 The Free Software Foundation
+ * Copyright (C) 1999-2005 authors
+ * Copyright (C) 2001-2002 Ximian, Inc.
+ * Copyright (C) 2005-2007 bulia byak
+ * Copyright (C) 2006 MenTaLguY
+ * Copyright (C) 2008 Jon A. Cruz
+ *
+ * Released under GNU GPL, read the file 'COPYING' for more information
+ */
+
+#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/canvas-bpath.h"
+#include "display/bezier-utils.h"
+
+#include <glib/gmem.h>
+#include "macros.h"
+#include "document.h"
+#include "selection.h"
+#include "desktop.h"
+#include "desktop-events.h"
+#include "desktop-handles.h"
+#include "desktop-affine.h"
+#include "desktop-style.h"
+#include "message-context.h"
+#include "prefs-utils.h"
+#include "pixmaps/cursor-eraser.xpm"
+#include "libnr/n-art-bpath.h"
+#include "libnr/nr-path.h"
+#include "libnr/nr-matrix-ops.h"
+#include "libnr/nr-scale-translate-ops.h"
+#include "xml/repr.h"
+#include "context-fns.h"
+#include "sp-item.h"
+#include "inkscape.h"
+#include "color.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 "isnan.h"
+
+#include "eraser-context.h"
+
+#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
+
+
+static void sp_eraser_context_class_init(SPEraserContextClass *klass);
+static void sp_eraser_context_init(SPEraserContext *erc);
+static void sp_eraser_context_dispose(GObject *object);
+
+static void sp_eraser_context_setup(SPEventContext *ec);
+static void sp_eraser_context_set(SPEventContext *ec, gchar const *key, gchar const *val);
+static gint sp_eraser_context_root_handler(SPEventContext *ec, GdkEvent *event);
+
+static void clear_current(SPEraserContext *dc);
+static void set_to_accumulated(SPEraserContext *dc);
+static void add_cap(SPCurve *curve, NR::Point const &pre, NR::Point const &from, NR::Point const &to, NR::Point const &post, double rounding);
+static void accumulate_eraser(SPEraserContext *dc);
+
+static void fit_and_split(SPEraserContext *erc, gboolean release);
+
+static void sp_eraser_reset(SPEraserContext *erc, NR::Point p);
+static NR::Point sp_eraser_get_npoint(SPEraserContext const *erc, NR::Point v);
+static NR::Point sp_eraser_get_vpoint(SPEraserContext const *erc, NR::Point n);
+static void draw_temporary_box(SPEraserContext *dc);
+
+
+static SPEventContextClass *parent_class;
+
+GtkType
+sp_eraser_context_get_type(void)
+{
+    static GType type = 0;
+    if (!type) {
+        GTypeInfo info = {
+            sizeof(SPEraserContextClass),
+            NULL, NULL,
+            (GClassInitFunc) sp_eraser_context_class_init,
+            NULL, NULL,
+            sizeof(SPEraserContext),
+            4,
+            (GInstanceInitFunc) sp_eraser_context_init,
+            NULL,   /* value_table */
+        };
+        type = g_type_register_static(SP_TYPE_EVENT_CONTEXT, "SPEraserContext", &info, (GTypeFlags)0);
+    }
+    return type;
+}
+
+static void
+sp_eraser_context_class_init(SPEraserContextClass *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_eraser_context_dispose;
+
+    event_context_class->setup = sp_eraser_context_setup;
+    event_context_class->set = sp_eraser_context_set;
+    event_context_class->root_handler = sp_eraser_context_root_handler;
+}
+
+static void
+sp_eraser_context_init(SPEraserContext *erc)
+{
+    SPEventContext *event_context = SP_EVENT_CONTEXT(erc);
+
+    event_context->cursor_shape = cursor_eraser_xpm;
+    event_context->hot_x = 4;
+    event_context->hot_y = 4;
+
+    erc->accumulated = NULL;
+    erc->segments = NULL;
+    erc->currentcurve = NULL;
+    erc->currentshape = NULL;
+    erc->npoints = 0;
+    erc->cal1 = NULL;
+    erc->cal2 = NULL;
+    erc->repr = NULL;
+
+    /* Eraser values */
+    erc->cur = NR::Point(0,0);
+    erc->last = NR::Point(0,0);
+    erc->vel = NR::Point(0,0);
+    erc->vel_max = 0;
+    erc->acc = NR::Point(0,0);
+    erc->ang = NR::Point(0,0);
+    erc->del = NR::Point(0,0);
+
+    /* attributes */
+    erc->dragging = FALSE;
+
+    erc->mass = 0.3;
+    erc->drag = DRAG_DEFAULT;
+    erc->angle = 30.0;
+    erc->width = 0.2;
+    erc->pressure = ERC_DEFAULT_PRESSURE;
+
+    erc->vel_thin = 0.1;
+    erc->flatness = 0.9;
+    erc->cap_rounding = 0.0;
+
+    erc->abs_width = false;
+}
+
+static void
+sp_eraser_context_dispose(GObject *object)
+{
+    SPEraserContext *erc = SP_ERASER_CONTEXT(object);
+
+    if (erc->accumulated) {
+        erc->accumulated = sp_curve_unref(erc->accumulated);
+    }
+
+    while (erc->segments) {
+        gtk_object_destroy(GTK_OBJECT(erc->segments->data));
+        erc->segments = g_slist_remove(erc->segments, erc->segments->data);
+    }
+
+    if (erc->currentcurve) erc->currentcurve = sp_curve_unref(erc->currentcurve);
+    if (erc->cal1) erc->cal1 = sp_curve_unref(erc->cal1);
+    if (erc->cal2) erc->cal2 = sp_curve_unref(erc->cal2);
+
+    if (erc->currentshape) {
+        gtk_object_destroy(GTK_OBJECT(erc->currentshape));
+        erc->currentshape = NULL;
+    }
+
+    if (erc->_message_context) {
+        delete erc->_message_context;
+    }
+
+    G_OBJECT_CLASS(parent_class)->dispose(object);
+}
+
+static void
+sp_eraser_context_setup(SPEventContext *ec)
+{
+    SPEraserContext *erc = SP_ERASER_CONTEXT(ec);
+
+    if (((SPEventContextClass *) parent_class)->setup)
+        ((SPEventContextClass *) parent_class)->setup(ec);
+
+    erc->accumulated = sp_curve_new_sized(32);
+    erc->currentcurve = sp_curve_new_sized(4);
+
+    erc->cal1 = sp_curve_new_sized(32);
+    erc->cal2 = sp_curve_new_sized(32);
+
+    erc->currentshape = sp_canvas_item_new(sp_desktop_sketch(ec->desktop), SP_TYPE_CANVAS_BPATH, NULL);
+    sp_canvas_bpath_set_fill(SP_CANVAS_BPATH(erc->currentshape), ERC_RED_RGBA, SP_WIND_RULE_EVENODD);
+    sp_canvas_bpath_set_stroke(SP_CANVAS_BPATH(erc->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(erc->currentshape), "event", G_CALLBACK(sp_desktop_root_handler), ec->desktop);
+
+/*
+static ProfileFloatElement f_profile[PROFILE_FLOAT_SIZE] = {
+    {"mass",0.02, 0.0, 1.0},
+    {"wiggle",0.0, 0.0, 1.0},
+    {"angle",30.0, -90.0, 90.0},
+    {"thinning",0.1, -1.0, 1.0},
+    {"tremor",0.0, 0.0, 1.0},
+    {"flatness",0.9, 0.0, 1.0},
+    {"cap_rounding",0.0, 0.0, 5.0}
+};
+*/
+
+    sp_event_context_read(ec, "mass");
+    sp_event_context_read(ec, "wiggle");
+    sp_event_context_read(ec, "angle");
+    sp_event_context_read(ec, "width");
+    sp_event_context_read(ec, "thinning");
+    sp_event_context_read(ec, "tremor");
+    sp_event_context_read(ec, "flatness");
+    sp_event_context_read(ec, "tracebackground");
+    sp_event_context_read(ec, "usepressure");
+    sp_event_context_read(ec, "usetilt");
+    sp_event_context_read(ec, "abs_width");
+    sp_event_context_read(ec, "cap_rounding");
+
+    erc->is_drawing = false;
+
+    erc->_message_context = new Inkscape::MessageContext((ec->desktop)->messageStack());
+
+    if (prefs_get_int_attribute("tools.eraser", "selcue", 0) != 0) {
+        ec->enableSelectionCue();
+    }
+// TODO temp force:
+    ec->enableSelectionCue();
+
+}
+
+static void
+sp_eraser_context_set(SPEventContext *ec, gchar const *key, gchar const *val)
+{
+    SPEraserContext *erc = SP_ERASER_CONTEXT(ec);
+
+    if (!strcmp(key, "mass")) {
+        double const dval = ( val ? g_ascii_strtod (val, NULL) : 0.2 );
+        erc->mass = CLAMP(dval, -1000.0, 1000.0);
+    } else if (!strcmp(key, "wiggle")) {
+        double const dval = ( val ? g_ascii_strtod (val, NULL) : (1 - DRAG_DEFAULT));
+        erc->drag = CLAMP((1 - dval), DRAG_MIN, DRAG_MAX); // drag is inverse to wiggle
+    } else if (!strcmp(key, "angle")) {
+        double const dval = ( val ? g_ascii_strtod (val, NULL) : 0.0);
+        erc->angle = CLAMP (dval, -90, 90);
+    } else if (!strcmp(key, "width")) {
+        double const dval = ( val ? g_ascii_strtod (val, NULL) : 0.1 );
+        erc->width = CLAMP(dval, -1000.0, 1000.0);
+    } else if (!strcmp(key, "thinning")) {
+        double const dval = ( val ? g_ascii_strtod (val, NULL) : 0.1 );
+        erc->vel_thin = CLAMP(dval, -1.0, 1.0);
+    } else if (!strcmp(key, "tremor")) {
+        double const dval = ( val ? g_ascii_strtod (val, NULL) : 0.0 );
+        erc->tremor = CLAMP(dval, 0.0, 1.0);
+    } else if (!strcmp(key, "flatness")) {
+        double const dval = ( val ? g_ascii_strtod (val, NULL) : 1.0 );
+        erc->flatness = CLAMP(dval, 0, 1.0);
+    } else if (!strcmp(key, "usepressure")) {
+        erc->usepressure = (val && strcmp(val, "0"));
+    } else if (!strcmp(key, "usetilt")) {
+        erc->usetilt = (val && strcmp(val, "0"));
+    } else if (!strcmp(key, "abs_width")) {
+        erc->abs_width = (val && strcmp(val, "0"));
+    } else if (!strcmp(key, "cap_rounding")) {
+        erc->cap_rounding = ( val ? g_ascii_strtod (val, NULL) : 0.0 );
+    }
+
+    //g_print("ERC: %g %g %g %g\n", erc->mass, erc->drag, erc->angle, erc->width);
+}
+
+static double
+flerp(double f0, double f1, double p)
+{
+    return f0 + ( f1 - f0 ) * p;
+}
+
+/* Get normalized point */
+static NR::Point
+sp_eraser_get_npoint(SPEraserContext const *dc, NR::Point v)
+{
+    NR::Rect drect = SP_EVENT_CONTEXT(dc)->desktop->get_display_area();
+    double const max = MAX ( drect.dimensions()[NR::X], drect.dimensions()[NR::Y] );
+    return NR::Point(( v[NR::X] - drect.min()[NR::X] ) / max,  ( v[NR::Y] - drect.min()[NR::Y] ) / max);
+}
+
+/* Get view point */
+static NR::Point
+sp_eraser_get_vpoint(SPEraserContext const *dc, NR::Point n)
+{
+    NR::Rect drect = SP_EVENT_CONTEXT(dc)->desktop->get_display_area();
+    double const max = MAX ( drect.dimensions()[NR::X], drect.dimensions()[NR::Y] );
+    return NR::Point(n[NR::X] * max + drect.min()[NR::X], n[NR::Y] * max + drect.min()[NR::Y]);
+}
+
+static void
+sp_eraser_reset(SPEraserContext *dc, NR::Point p)
+{
+    dc->last = dc->cur = sp_eraser_get_npoint(dc, p);
+    dc->vel = NR::Point(0,0);
+    dc->vel_max = 0;
+    dc->acc = NR::Point(0,0);
+    dc->ang = NR::Point(0,0);
+    dc->del = NR::Point(0,0);
+}
+
+static void
+sp_eraser_extinput(SPEraserContext *dc, GdkEvent *event)
+{
+    if (gdk_event_get_axis (event, GDK_AXIS_PRESSURE, &dc->pressure))
+        dc->pressure = CLAMP (dc->pressure, ERC_MIN_PRESSURE, ERC_MAX_PRESSURE);
+    else
+        dc->pressure = ERC_DEFAULT_PRESSURE;
+
+    if (gdk_event_get_axis (event, GDK_AXIS_XTILT, &dc->xtilt))
+        dc->xtilt = CLAMP (dc->xtilt, ERC_MIN_TILT, ERC_MAX_TILT);
+    else
+        dc->xtilt = ERC_DEFAULT_TILT;
+
+    if (gdk_event_get_axis (event, GDK_AXIS_YTILT, &dc->ytilt))
+        dc->ytilt = CLAMP (dc->ytilt, ERC_MIN_TILT, ERC_MAX_TILT);
+    else
+        dc->ytilt = ERC_DEFAULT_TILT;
+}
+
+
+static gboolean
+sp_eraser_apply(SPEraserContext *dc, NR::Point p)
+{
+    NR::Point n = sp_eraser_get_npoint(dc, p);
+
+    /* Calculate mass and drag */
+    double const mass = flerp(1.0, 160.0, dc->mass);
+    double const drag = flerp(0.0, 0.5, dc->drag * dc->drag);
+
+    /* Calculate force and acceleration */
+    NR::Point force = n - dc->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 ( NR::L2(force) < ERASER_EPSILON || (dc->vel_max < ERASER_VEL_START && NR::L2(force) < ERASER_EPSILON_START)) {
+        return FALSE;
+    }
+
+    dc->acc = force / mass;
+
+    /* Calculate new velocity */
+    dc->vel += dc->acc;
+
+    if (NR::L2(dc->vel) > dc->vel_max)
+        dc->vel_max = NR::L2(dc->vel);
+
+    /* Calculate angle of drawing tool */
+
+    double a1;
+    if (dc->usetilt) {
+        // 1a. calculate nib angle from input device tilt:
+        gdouble length = std::sqrt(dc->xtilt*dc->xtilt + dc->ytilt*dc->ytilt);;
+
+        if (length > 0) {
+            NR::Point ang1 = NR::Point(dc->ytilt/length, dc->xtilt/length);
+            a1 = atan2(ang1);
+        }
+        else
+            a1 = 0.0;
+    }
+    else {
+        // 1b. fixed dc->angle (absolutely flat nib):
+        double const radians = ( (dc->angle - 90) / 180.0 ) * M_PI;
+        NR::Point ang1 = NR::Point(-sin(radians),  cos(radians));
+        a1 = atan2(ang1);
+    }
+
+    // 2. perpendicular to dc->vel (absolutely non-flat nib):
+    gdouble const mag_vel = NR::L2(dc->vel);
+    if ( mag_vel < ERASER_EPSILON ) {
+        return FALSE;
+    }
+    NR::Point ang2 = NR::rot90(dc->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 - dc->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 = NR::L2(NR::Point (cos (new_ang), sin (new_ang)) - dc->ang);
+    if ( angle_delta / NR::L2(dc->vel) > 4000 ) {
+        return FALSE;
+    }
+
+    // convert to point
+    dc->ang = NR::Point (cos (new_ang), sin (new_ang));
+
+//    g_print ("force %g  acc %g  vel_max %g  vel %g  a1 %g  a2 %g  new_ang %g\n", NR::L2(force), NR::L2(dc->acc), dc->vel_max, NR::L2(dc->vel), a1, a2, new_ang);
+
+    /* Apply drag */
+    dc->vel *= 1.0 - drag;
+
+    /* Update position */
+    dc->last = dc->cur;
+    dc->cur += dc->vel;
+
+    return TRUE;
+}
+
+static void
+sp_eraser_brush(SPEraserContext *dc)
+{
+    g_assert( dc->npoints >= 0 && dc->npoints < SAMPLING_SIZE );
+
+    // How much velocity thins strokestyle
+    double vel_thin = flerp (0, 160, dc->vel_thin);
+
+    // Influence of pressure on thickness
+    double pressure_thick = (dc->usepressure ? dc->pressure : 1.0);
+
+    // get the real brush point, not the same as pointer (affected by hatch tracking and/or mass
+    // drag)
+    NR::Point brush = sp_eraser_get_vpoint(dc, dc->cur);
+    NR::Point brush_w = SP_EVENT_CONTEXT(dc)->desktop->d2w(brush); 
+
+    double trace_thick = 1;
+
+    double width = (pressure_thick * trace_thick - vel_thin * NR::L2(dc->vel)) * dc->width;
+
+    double tremble_left = 0, tremble_right = 0;
+    if (dc->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)*dc->tremor * (0.15 + 0.8*width) * (0.35 + 14*NR::L2(dc->vel));
+        tremble_right = (y2)*dc->tremor * (0.15 + 0.8*width) * (0.35 + 14*NR::L2(dc->vel));
+    }
+
+    if ( width < 0.02 * dc->width ) {
+        width = 0.02 * dc->width;
+    }
+
+    double dezoomify_factor = 0.05 * 1000;
+    if (!dc->abs_width) {
+        dezoomify_factor /= SP_EVENT_CONTEXT(dc)->desktop->current_zoom();
+    }
+
+    NR::Point del_left = dezoomify_factor * (width + tremble_left) * dc->ang;
+    NR::Point del_right = dezoomify_factor * (width + tremble_right) * dc->ang;
+
+    dc->point1[dc->npoints] = brush + del_left;
+    dc->point2[dc->npoints] = brush - del_right;
+
+    dc->del = 0.5*(del_left + del_right);
+
+    dc->npoints++;
+}
+
+void
+sp_erc_update_toolbox (SPDesktop *desktop, const gchar *id, double value)
+{
+    desktop->setToolboxAdjustmentValue (id, value);
+}
+
+static void
+eraser_cancel(SPEraserContext *dc)
+{
+    SPDesktop *desktop = SP_EVENT_CONTEXT(dc)->desktop;
+    dc->dragging = FALSE;
+    dc->is_drawing = false;
+    sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate), 0);
+            /* Remove all temporary line segments */
+            while (dc->segments) {
+                gtk_object_destroy(GTK_OBJECT(dc->segments->data));
+                dc->segments = g_slist_remove(dc->segments, dc->segments->data);
+            }
+            /* reset accumulated curve */
+            sp_curve_reset(dc->accumulated);
+            clear_current(dc);
+            if (dc->repr) {
+                dc->repr = NULL;
+            }
+}
+
+
+gint
+sp_eraser_context_root_handler(SPEventContext *event_context,
+                                  GdkEvent *event)
+{
+    SPEraserContext *dc = SP_ERASER_CONTEXT(event_context);
+    SPDesktop *desktop = event_context->desktop;
+
+    gint ret = FALSE;
+
+    switch (event->type) {
+        case GDK_BUTTON_PRESS:
+            if (event->button.button == 1 && !event_context->space_panning) {
+
+                SPDesktop *desktop = SP_EVENT_CONTEXT_DESKTOP(dc);
+
+                if (Inkscape::have_viable_layer(desktop, dc->_message_context) == false) {
+                    return TRUE;
+                }
+
+                NR::Point const button_w(event->button.x,
+                                         event->button.y);
+                NR::Point const button_dt(desktop->w2d(button_w));
+                sp_eraser_reset(dc, button_dt);
+                sp_eraser_extinput(dc, event);
+                sp_eraser_apply(dc, button_dt);
+                sp_curve_reset(dc->accumulated);
+                if (dc->repr) {
+                    dc->repr = NULL;
+                }
+
+                /* initialize first point */
+                dc->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;
+
+                sp_canvas_force_full_redraw_after_interruptions(desktop->canvas, 3);
+                dc->is_drawing = true;
+            }
+            break;
+        case GDK_MOTION_NOTIFY:
+        {
+            NR::Point const motion_w(event->motion.x,
+                                     event->motion.y);
+            NR::Point motion_dt(desktop->w2d(motion_w));
+            sp_eraser_extinput(dc, event);
+
+            dc->_message_context->clear();
+
+            if ( dc->is_drawing && (event->motion.state & GDK_BUTTON1_MASK) && !event_context->space_panning) {
+                dc->dragging = TRUE;
+
+                dc->_message_context->set(Inkscape::NORMAL_MESSAGE, _("<b>Drawing</b> a eraser stroke"));
+
+                if (!sp_eraser_apply(dc, motion_dt)) {
+                    ret = TRUE;
+                    break;
+                }
+
+                if ( dc->cur != dc->last ) {
+                    sp_eraser_brush(dc);
+                    g_assert( dc->npoints > 0 );
+                    fit_and_split(dc, FALSE);
+                }
+                ret = TRUE;
+            }
+        }
+        break;
+
+
+    case GDK_BUTTON_RELEASE:
+    {
+        NR::Point const motion_w(event->button.x, event->button.y);
+        NR::Point const motion_dt(desktop->w2d(motion_w));
+
+        sp_canvas_item_ungrab(SP_CANVAS_ITEM(desktop->acetate), event->button.time);
+        sp_canvas_end_forced_full_redraws(desktop->canvas);
+        dc->is_drawing = false;
+
+        if (dc->dragging && event->button.button == 1 && !event_context->space_panning) {
+            dc->dragging = FALSE;
+
+            sp_eraser_apply(dc, motion_dt);
+
+            /* Remove all temporary line segments */
+            while (dc->segments) {
+                gtk_object_destroy(GTK_OBJECT(dc->segments->data));
+                dc->segments = g_slist_remove(dc->segments, dc->segments->data);
+            }
+
+            /* Create object */
+            fit_and_split(dc, TRUE);
+            accumulate_eraser(dc);
+            set_to_accumulated(dc); // performs document_done
+
+            /* reset accumulated curve */
+            sp_curve_reset(dc->accumulated);
+
+            clear_current(dc);
+            if (dc->repr) {
+                dc->repr = NULL;
+            }
+
+            dc->_message_context->clear();
+            ret = TRUE;
+        }
+        break;
+    }
+
+    case GDK_KEY_PRESS:
+        switch (get_group0_keyval (&event->key)) {
+        case GDK_Up:
+        case GDK_KP_Up:
+            if (!MOD__CTRL_ONLY) {
+                dc->angle += 5.0;
+                if (dc->angle > 90.0)
+                    dc->angle = 90.0;
+                sp_erc_update_toolbox (desktop, "eraser-angle", dc->angle);
+                ret = TRUE;
+            }
+            break;
+        case GDK_Down:
+        case GDK_KP_Down:
+            if (!MOD__CTRL_ONLY) {
+                dc->angle -= 5.0;
+                if (dc->angle < -90.0)
+                    dc->angle = -90.0;
+                sp_erc_update_toolbox (desktop, "eraser-angle", dc->angle);
+                ret = TRUE;
+            }
+            break;
+        case GDK_Right:
+        case GDK_KP_Right:
+            if (!MOD__CTRL_ONLY) {
+                dc->width += 0.01;
+                if (dc->width > 1.0)
+                    dc->width = 1.0;
+                sp_erc_update_toolbox (desktop, "altx-eraser", dc->width * 100); // the same spinbutton is for alt+x
+                ret = TRUE;
+            }
+            break;
+        case GDK_Left:
+        case GDK_KP_Left:
+            if (!MOD__CTRL_ONLY) {
+                dc->width -= 0.01;
+                if (dc->width < 0.01)
+                    dc->width = 0.01;
+                sp_erc_update_toolbox (desktop, "altx-eraser", dc->width * 100);
+                ret = TRUE;
+            }
+            break;
+        case GDK_Home:
+        case GDK_KP_Home:
+            dc->width = 0.01;
+            sp_erc_update_toolbox (desktop, "altx-eraser", dc->width * 100);
+            ret = TRUE;
+            break;
+        case GDK_End:
+        case GDK_KP_End:
+            dc->width = 1.0;
+            sp_erc_update_toolbox (desktop, "altx-eraser", dc->width * 100);
+            ret = TRUE;
+            break;
+        case GDK_x:
+        case GDK_X:
+            if (MOD__ALT_ONLY) {
+                desktop->setToolboxFocusTo ("altx-eraser");
+                ret = TRUE;
+            }
+            break;
+        case GDK_Escape:
+            if (dc->is_drawing) {
+                // if drawing, cancel, otherwise pass it up for deselecting
+                eraser_cancel (dc);
+                ret = TRUE;
+            }
+            break;
+        case GDK_z:
+        case GDK_Z:
+            if (MOD__CTRL_ONLY && dc->is_drawing) {
+                // if drawing, cancel, otherwise pass it up for undo
+                eraser_cancel (dc);
+                ret = TRUE;
+            }
+            break;
+        default:
+            break;
+        }
+        break;
+
+    case GDK_KEY_RELEASE:
+        switch (get_group0_keyval(&event->key)) {
+            case GDK_Control_L:
+            case GDK_Control_R:
+                dc->_message_context->clear();
+                break;
+            default:
+                break;
+        }
+
+    default:
+        break;
+    }
+
+    if (!ret) {
+        if (((SPEventContextClass *) parent_class)->root_handler) {
+            ret = ((SPEventContextClass *) parent_class)->root_handler(event_context, event);
+        }
+    }
+
+    return ret;
+}
+
+
+static void
+clear_current(SPEraserContext *dc)
+{
+    /* reset bpath */
+    sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->currentshape), NULL);
+    /* reset curve */
+    sp_curve_reset(dc->currentcurve);
+    sp_curve_reset(dc->cal1);
+    sp_curve_reset(dc->cal2);
+    /* reset points */
+    dc->npoints = 0;
+}
+
+static void
+set_to_accumulated(SPEraserContext *dc)
+{
+    SPDesktop *desktop = SP_EVENT_CONTEXT(dc)->desktop;
+
+    if (!sp_curve_empty(dc->accumulated)) {
+        NArtBpath *abp;
+        gchar *str;
+
+        if (!dc->repr) {
+            /* Create object */
+            Inkscape::XML::Document *xml_doc = sp_document_repr_doc(desktop->doc());
+            Inkscape::XML::Node *repr = xml_doc->createElement("svg:path");
+
+            /* Set style */
+            sp_desktop_apply_style_tool (desktop, repr, "tools.eraser", false);
+
+            dc->repr = repr;
+
+            SPItem *item=SP_ITEM(desktop->currentLayer()->appendChildRepr(dc->repr));
+            Inkscape::GC::release(dc->repr);
+            item->transform = SP_ITEM(desktop->currentRoot())->getRelativeTransform(desktop->currentLayer());
+            item->updateRepr();
+        }
+        abp = nr_artpath_affine(sp_curve_first_bpath(dc->accumulated), sp_desktop_dt2root_affine(desktop));
+        str = sp_svg_write_path(abp);
+        g_assert( str != NULL );
+        g_free(abp);
+        dc->repr->setAttribute("d", str);
+        g_free(str);
+
+        if ( dc->repr ) {
+            Inkscape::Selection *selection = sp_desktop_selection(desktop);
+            gint eraserMode = (prefs_get_int_attribute("tools.eraser", "mode", 0) != 0) ? 1 : 0;
+            Inkscape::XML::Document *xml_doc = sp_document_repr_doc(desktop->doc());
+            if (!selection->isEmpty()) {
+                // Do selection-limited
+                if ( eraserMode == 0 ) {
+                    // Nuke
+                } else {
+                    // Cut-out
+                    std::vector<SPItem*> putBacks;
+                    GSList const *selected = g_slist_copy(const_cast<GSList *>(selection->itemList()));
+                    for (GSList const *i = selected ; i ; i = i->next ) {
+                        SPItem *item = SP_ITEM(i->data);
+                        Inkscape::XML::Node* dup = dc->repr->duplicate(xml_doc);
+                        dc->repr->parent()->appendChild(dup);
+                        Inkscape::GC::release(dup);
+
+                        selection->set(item);
+                        selection->add(dup);
+                        sp_selected_path_diff();
+                        if ( !selection->isEmpty() ) {
+                            // If the item was not completely erased, add it back to the selection.
+                            GSList const *selected2 = g_slist_copy(const_cast<GSList *>(selection->itemList()));
+                            for (GSList const *i2 = selected2 ; i2 ; i2 = i2->next ) {
+                                putBacks.push_back(SP_ITEM(i2->data));
+                            }
+                        }
+                    }
+                    g_slist_free ((GSList *) selected);
+
+                    selection->clear();
+                    selection->add(putBacks.begin(), putBacks.end());
+                }
+            } else {
+                // TODO finish
+            }
+
+
+            // Remove the eraser stroke itself:
+            sp_repr_unparent( dc->repr );
+            dc->repr = 0;
+        }
+//         SP_OBJECT(item)->deleteObject(propagate, propagate_descendants);
+//         sp_object_unref((SPObject *)item, NULL);
+    } else {
+        if (dc->repr) {
+            sp_repr_unparent(dc->repr);
+            dc->repr = 0;
+        }
+    }
+
+    sp_document_done(sp_desktop_document(desktop), SP_VERB_CONTEXT_ERASER, 
+                     _("Draw eraser stroke"));
+}
+
+static void
+add_cap(SPCurve *curve,
+        NR::Point const &pre, NR::Point const &from,
+        NR::Point const &to, NR::Point const &post,
+        double rounding)
+{
+    NR::Point vel = rounding * NR::rot90( to - from ) / sqrt(2.0);
+    double mag = NR::L2(vel);
+
+    NR::Point v_in = from - pre;
+    double mag_in = NR::L2(v_in);
+    if ( mag_in > ERASER_EPSILON ) {
+        v_in = mag * v_in / mag_in;
+    } else {
+        v_in = NR::Point(0, 0);
+    }
+
+    NR::Point v_out = to - post;
+    double mag_out = NR::L2(v_out);
+    if ( mag_out > ERASER_EPSILON ) {
+        v_out = mag * v_out / mag_out;
+    } else {
+        v_out = NR::Point(0, 0);
+    }
+
+    if ( NR::L2(v_in) > ERASER_EPSILON || NR::L2(v_out) > ERASER_EPSILON ) {
+        sp_curve_curveto(curve, from + v_in, to + v_out, to);
+    }
+}
+
+static void
+accumulate_eraser(SPEraserContext *dc)
+{
+    if ( !sp_curve_empty(dc->cal1) && !sp_curve_empty(dc->cal2) ) {
+        sp_curve_reset(dc->accumulated); /*  Is this required ?? */
+        SPCurve *rev_cal2 = sp_curve_reverse(dc->cal2);
+
+        g_assert(dc->cal1->end > 1);
+        g_assert(rev_cal2->end > 1);
+        g_assert(SP_CURVE_SEGMENT(dc->cal1, 0)->code == NR_MOVETO_OPEN);
+        g_assert(SP_CURVE_SEGMENT(rev_cal2, 0)->code == NR_MOVETO_OPEN);
+        g_assert(SP_CURVE_SEGMENT(dc->cal1, 1)->code == NR_CURVETO);
+        g_assert(SP_CURVE_SEGMENT(rev_cal2, 1)->code == NR_CURVETO);
+        g_assert(SP_CURVE_SEGMENT(dc->cal1, dc->cal1->end-1)->code == NR_CURVETO);
+        g_assert(SP_CURVE_SEGMENT(rev_cal2, rev_cal2->end-1)->code == NR_CURVETO);
+
+        sp_curve_append(dc->accumulated, dc->cal1, FALSE);
+
+        add_cap(dc->accumulated, SP_CURVE_SEGMENT(dc->cal1, dc->cal1->end-1)->c(2), SP_CURVE_SEGMENT(dc->cal1, dc->cal1->end-1)->c(3), SP_CURVE_SEGMENT(rev_cal2, 0)->c(3), SP_CURVE_SEGMENT(rev_cal2, 1)->c(1), dc->cap_rounding);
+
+        sp_curve_append(dc->accumulated, rev_cal2, TRUE);
+
+        add_cap(dc->accumulated, SP_CURVE_SEGMENT(rev_cal2, rev_cal2->end-1)->c(2), SP_CURVE_SEGMENT(rev_cal2, rev_cal2->end-1)->c(3), SP_CURVE_SEGMENT(dc->cal1, 0)->c(3), SP_CURVE_SEGMENT(dc->cal1, 1)->c(1), dc->cap_rounding);
+
+        sp_curve_closepath(dc->accumulated);
+
+        sp_curve_unref(rev_cal2);
+
+        sp_curve_reset(dc->cal1);
+        sp_curve_reset(dc->cal2);
+    }
+}
+
+static double square(double const x)
+{
+    return x * x;
+}
+
+static void
+fit_and_split(SPEraserContext *dc, gboolean release)
+{
+    double const tolerance_sq = square( NR::expansion(SP_EVENT_CONTEXT(dc)->desktop->w2d()) * TOLERANCE_ERASER );
+
+#ifdef ERASER_VERBOSE
+    g_print("[F&S:R=%c]", release?'T':'F');
+#endif
+
+    if (!( dc->npoints > 0 && dc->npoints < SAMPLING_SIZE ))
+        return; // just clicked
+
+    if ( dc->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:#] dc->npoints:%d, release:%s\n",
+                dc->npoints, release ? "TRUE" : "FALSE");
+#endif
+
+        /* Current eraser */
+        if ( dc->cal1->end == 0 || dc->cal2->end == 0 ) {
+            /* dc->npoints > 0 */
+            /* g_print("erasers(1|2) reset\n"); */
+            sp_curve_reset(dc->cal1);
+            sp_curve_reset(dc->cal2);
+
+            sp_curve_moveto(dc->cal1, dc->point1[0]);
+            sp_curve_moveto(dc->cal2, dc->point2[0]);
+        }
+
+        NR::Point b1[BEZIER_MAX_LENGTH];
+        gint const nb1 = sp_bezier_fit_cubic_r(b1, dc->point1, dc->npoints,
+                                               tolerance_sq, BEZIER_MAX_BEZIERS);
+        g_assert( nb1 * BEZIER_SIZE <= gint(G_N_ELEMENTS(b1)) );
+
+        NR::Point b2[BEZIER_MAX_LENGTH];
+        gint const nb2 = sp_bezier_fit_cubic_r(b2, dc->point2, dc->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) {
+                sp_curve_reset(dc->currentcurve);
+                sp_curve_moveto(dc->currentcurve, b1[0]);
+                for (NR::Point *bp1 = b1; bp1 < b1 + BEZIER_SIZE * nb1; bp1 += BEZIER_SIZE) {
+                    sp_curve_curveto(dc->currentcurve, bp1[1],
+                                     bp1[2], bp1[3]);
+                }
+                sp_curve_lineto(dc->currentcurve,
+                                b2[BEZIER_SIZE*(nb2-1) + 3]);
+                for (NR::Point *bp2 = b2 + BEZIER_SIZE * ( nb2 - 1 ); bp2 >= b2; bp2 -= BEZIER_SIZE) {
+                    sp_curve_curveto(dc->currentcurve, bp2[2], bp2[1], bp2[0]);
+                }
+                // FIXME: dc->segments is always NULL at this point??
+                if (!dc->segments) { // first segment
+                    add_cap(dc->currentcurve, b2[1], b2[0], b1[0], b1[1], dc->cap_rounding);
+                }
+                sp_curve_closepath(dc->currentcurve);
+                sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->currentshape), dc->currentcurve);
+            }
+
+            /* Current eraser */
+            for (NR::Point *bp1 = b1; bp1 < b1 + BEZIER_SIZE * nb1; bp1 += BEZIER_SIZE) {
+                sp_curve_curveto(dc->cal1, bp1[1], bp1[2], bp1[3]);
+            }
+            for (NR::Point *bp2 = b2; bp2 < b2 + BEZIER_SIZE * nb2; bp2 += BEZIER_SIZE) {
+                sp_curve_curveto(dc->cal2, bp2[1], bp2[2], bp2[3]);
+            }
+        } else {
+            /* fixme: ??? */
+#ifdef ERASER_VERBOSE
+            g_print("[fit_and_split] failed to fit-cubic.\n");
+#endif
+            draw_temporary_box(dc);
+
+            for (gint i = 1; i < dc->npoints; i++) {
+                sp_curve_lineto(dc->cal1, dc->point1[i]);
+            }
+            for (gint i = 1; i < dc->npoints; i++) {
+                sp_curve_lineto(dc->cal2, dc->point2[i]);
+            }
+        }
+
+        /* Fit and draw and copy last point */
+#ifdef ERASER_VERBOSE
+        g_print("[%d]Yup\n", dc->npoints);
+#endif
+        if (!release) {
+            g_assert(!sp_curve_empty(dc->currentcurve));
+
+            SPCanvasItem *cbp = sp_canvas_item_new(sp_desktop_sketch(SP_EVENT_CONTEXT(dc)->desktop),
+                                                   SP_TYPE_CANVAS_BPATH,
+                                                   NULL);
+            SPCurve *curve = sp_curve_copy(dc->currentcurve);
+            sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH (cbp), curve);
+            sp_curve_unref(curve);
+
+            guint32 fillColor = sp_desktop_get_color_tool (SP_ACTIVE_DESKTOP, "tools.eraser", true);
+            //guint32 strokeColor = sp_desktop_get_color_tool (SP_ACTIVE_DESKTOP, "tools.eraser", false);
+            double opacity = sp_desktop_get_master_opacity_tool (SP_ACTIVE_DESKTOP, "tools.eraser");
+            double fillOpacity = sp_desktop_get_opacity_tool (SP_ACTIVE_DESKTOP, "tools.eraser", true);
+            //double strokeOpacity = sp_desktop_get_opacity_tool (SP_ACTIVE_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), SP_EVENT_CONTEXT(dc)->desktop);
+
+            dc->segments = g_slist_prepend(dc->segments, cbp);
+        }
+
+        dc->point1[0] = dc->point1[dc->npoints - 1];
+        dc->point2[0] = dc->point2[dc->npoints - 1];
+        dc->npoints = 1;
+    } else {
+        draw_temporary_box(dc);
+    }
+}
+
+static void
+draw_temporary_box(SPEraserContext *dc)
+{
+    sp_curve_reset(dc->currentcurve);
+
+    sp_curve_moveto(dc->currentcurve, dc->point1[dc->npoints-1]);
+    for (gint i = dc->npoints-2; i >= 0; i--) {
+        sp_curve_lineto(dc->currentcurve, dc->point1[i]);
+    }
+    for (gint i = 0; i < dc->npoints; i++) {
+        sp_curve_lineto(dc->currentcurve, dc->point2[i]);
+    }
+    if (dc->npoints >= 2) {
+        add_cap(dc->currentcurve, dc->point2[dc->npoints-2], dc->point2[dc->npoints-1], dc->point1[dc->npoints-1], dc->point1[dc->npoints-2], dc->cap_rounding);
+    }
+
+    sp_curve_closepath(dc->currentcurve);
+    sp_canvas_bpath_set_bpath(SP_CANVAS_BPATH(dc->currentshape), dc->currentcurve);
+}
+
+/*
+  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 :

diff --git a/src/eraser-context.h b/src/eraser-context.h
new file mode 100644 (file)
index 0000000..bc86201
--- /dev/null
+++ b/src/eraser-context.h
@@ -0,0 +1,127 @@
+#ifndef SP_ERASER_CONTEXT_H_SEEN
+#define SP_ERASER_CONTEXT_H_SEEN
+
+/*
+ * Handwriting-like drawing mode
+ *
+ * Authors:
+ *   Mitsuru Oka <oka326@parkcity.ne.jp>
+ *   Lauris Kaplinski <lauris@kaplinski.com>
+ *
+ * The original dynadraw code:
+ *   Paul Haeberli <paul@sgi.com>
+ *
+ * Copyright (C) 1998 The Free Software Foundation
+ * Copyright (C) 1999-2002 authors
+ * Copyright (C) 2001-2002 Ximian, Inc.
+ * Copyright (C) 2008 Jon A. Cruz
+ *
+ * Released under GNU GPL, read the file 'COPYING' for more information
+ */
+
+#include "display/curve.h"
+#include "event-context.h"
+#include <display/display-forward.h>
+#include <libnr/nr-point.h>
+
+#define SP_TYPE_ERASER_CONTEXT (sp_eraser_context_get_type())
+#define SP_ERASER_CONTEXT(o) (GTK_CHECK_CAST((o), SP_TYPE_ERASER_CONTEXT, SPEraserContext))
+#define SP_ERASER_CONTEXT_CLASS(k) (GTK_CHECK_CLASS_CAST((k), SP_TYPE_ERASER_CONTEXT, SPEraserContextClass))
+#define SP_IS_ERASER_CONTEXT(o) (GTK_CHECK_TYPE((o), SP_TYPE_ERASER_CONTEXT))
+#define SP_IS_ERASER_CONTEXT_CLASS(k) (GTK_CHECK_CLASS_TYPE((k), SP_TYPE_ERASER_CONTEXT))
+
+class SPEraserContext;
+class SPEraserContextClass;
+
+#define SAMPLING_SIZE 8        /* fixme: ?? */
+
+#define ERC_MIN_PRESSURE      0.0
+#define ERC_MAX_PRESSURE      1.0
+#define ERC_DEFAULT_PRESSURE  1.0
+
+#define ERC_MIN_TILT         -1.0
+#define ERC_MAX_TILT          1.0
+#define ERC_DEFAULT_TILT      0.0
+
+struct SPEraserContext
+{
+    SPEventContext event_context;
+
+    /** accumulated shape which ultimately goes in svg:path */
+    SPCurve *accumulated;
+
+    /** canvas items for "comitted" segments */
+    GSList *segments;
+
+    /** canvas item for red "leading" segment */
+    SPCanvasItem *currentshape;
+    /** shape of red "leading" segment */
+    SPCurve *currentcurve;
+
+    /** left edge of the stroke; combined to get accumulated */
+    SPCurve *cal1;
+    /** right edge of the stroke; combined to get accumulated */
+    SPCurve *cal2;
+
+    /** left edge points for this segment */
+    NR::Point point1[SAMPLING_SIZE];
+    /** right edge points for this segment */
+    NR::Point point2[SAMPLING_SIZE];
+    /** number of edge points for this segment */
+    gint npoints;
+
+    /* repr */
+    Inkscape::XML::Node *repr;
+
+    /* Eraser */
+    NR::Point cur;
+    NR::Point vel;
+    double vel_max;
+    NR::Point acc;
+    NR::Point ang;
+    NR::Point last;
+    NR::Point del;
+    /* extended input data */
+    gdouble pressure;
+    gdouble xtilt;
+    gdouble ytilt;
+    /* attributes */
+    guint dragging : 1;           /* mouse state: mouse is dragging */
+    guint usepressure : 1;
+    guint usetilt : 1;
+    double mass, drag;
+    double angle;
+    double width;
+
+    double vel_thin;
+    double flatness;
+    double tremor;
+    double cap_rounding;
+
+    Inkscape::MessageContext *_message_context;
+
+    bool is_drawing;
+
+    /** uses absolute width independent of zoom */
+    bool abs_width;
+};
+
+struct SPEraserContextClass
+{
+    SPEventContextClass parent_class;
+};
+
+GtkType sp_eraser_context_get_type(void);
+
+#endif // SP_ERASER_CONTEXT_H_SEEN
+
+/*
+  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 :