rawTherapee/rtgui/labgrid.cc

/** -*- C++ -*-
 *
 *  This file is part of RawTherapee.
 *
 *  Copyright (c) 2017 Alberto Griggio <alberto.griggio@gmail.com>
 *
 *  Copyright (c) 2021 Jacques Desmis <jdesmis@gmail.com> for CIE xy graph
 *
 *  RawTherapee is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  RawTherapee is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with RawTherapee.  If not, see <https://www.gnu.org/licenses/>.
 */

// adapted from the "color correction" module of Darktable. Original copyright follows
/*
    copyright (c) 2009--2010 johannes hanika.

    darktable is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    darktable is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with darktable.  If not, see <https://www.gnu.org/licenses/>.
*/

#include "labgrid.h"

#include "../rtengine/color.h"
#include "options.h"
#include "rtimage.h"
#include "rtscalable.h"

using rtengine::Color;


//-----------------------------------------------------------------------------
// LabGridArea
//-----------------------------------------------------------------------------

bool LabGridArea::notifyListener()
{
    if (listener) {
        const auto round =
            [](float v) -> float
            {
                return int(v * 1000) / 1000.f;
            };
        if (! ciexy_enabled){
            listener->panelChanged(evt, Glib::ustring::compose(evtMsg, round(high_a), round(high_b), round(low_a), round(low_b)));
        } else {
            float high_a1 = 0.55f * (high_a + 1.f) - 0.1f;
            float high_b1 = 0.55f * (high_b + 1.f) - 0.1f;
            float low_a1 = 0.55f * (low_a + 1.f) - 0.1f;
            float low_b1 = 0.55f * (low_b + 1.f) - 0.1f;
            float gre_x1 = 0.55f * (gre_x + 1.f) - 0.1f;
            float gre_y1 = 0.55f * (gre_y + 1.f) - 0.1f;
            listener->panelChanged(evt, Glib::ustring::compose(evtMsg, round(low_a1), round(low_b1), round(gre_x1), round(gre_y1), round(high_a1), round(high_b1)));
        }
    }
    return false;
}


LabGridArea::LabGridArea(rtengine::ProcEvent evt, const Glib::ustring &msg, bool enable_low, bool ciexy, bool mous):
    Gtk::DrawingArea(),
    evt(evt), evtMsg(msg),
    litPoint(NONE),
    low_a(0.f), high_a(0.f), low_b(0.f), high_b(0.f), gre_x(0.f), gre_y(0.f), whi_x(0.f), whi_y(0.f), me_x(0.f), me_y(0.f),//these variables are used as xy in Ciexy - no change labels
    defaultLow_a(0.f), defaultHigh_a(0.f), defaultLow_b(0.f), defaultHigh_b(0.f), defaultgre_x(0.f), defaultgre_y(0.f), defaultwhi_x(0.f), defaultwhi_y(0.f), defaultme_x(0.f), defaultme_y(0.f),
    listener(nullptr),
    edited(false),
    isDragged(false),
    low_enabled(enable_low),
    ciexy_enabled(ciexy),
    mous_enabled(mous)
    

{
    set_can_focus(false); // prevent moving the grid while you're moving a point
    add_events(Gdk::EXPOSURE_MASK | Gdk::BUTTON_PRESS_MASK | Gdk::BUTTON_RELEASE_MASK | Gdk::POINTER_MOTION_MASK);
    set_name("LabGrid");
    get_style_context()->add_class("drawingarea");
}

void LabGridArea::getParams(double &la, double &lb, double &ha, double &hb, double &gx, double &gy, double &wx, double &wy, double &mx, double &my) const
{
    la = low_a;
    ha = high_a;
    lb = low_b;
    hb = high_b;
    gx = gre_x;
    gy = gre_y;
    wx = whi_x;
    wy = whi_y;
    mx = me_x;
    my = me_y;
 //  printf("la=%f ha=%f lb=%f hb=%f gx=%f gy=%f\n", la, ha, lb, hb, gx, gy);
}


void LabGridArea::setParams(double la, double lb, double ha, double hb, double gx, double gy, double wx, double wy, double mx, double my, bool notify)
{
    const double lo = -1.0;
    const double hi = 1.0;
    low_a = rtengine::LIM(la, lo, hi);
    low_b = rtengine::LIM(lb, lo, hi);
    high_a = rtengine::LIM(ha, lo, hi);
    high_b = rtengine::LIM(hb, lo, hi);
    gre_x = rtengine::LIM(gx, lo, hi);
    gre_y = rtengine::LIM(gy, lo, hi);
    whi_x = rtengine::LIM(wx, lo, hi);
    whi_y = rtengine::LIM(wy, lo, hi);
    me_x = rtengine::LIM(mx, lo, hi);
    me_y = rtengine::LIM(my, lo, hi);

    queue_draw();
    if (notify) {
        notifyListener();
    }
}

void LabGridArea::setDefault (double la, double lb, double ha, double hb, double gx, double gy, double wx, double wy, double mx, double my)
{
    defaultLow_a = la;
    defaultLow_b = lb;
    defaultHigh_a = ha;
    defaultHigh_b = hb;
    defaultgre_x = gx;
    defaultgre_y = gy;
    defaultwhi_x = wx;
    defaultwhi_y = wy;
    defaultme_x = mx;
    defaultme_y = my;
}


void LabGridArea::reset(bool toInitial)
{
    if (toInitial) {
        setParams(defaultLow_a, defaultLow_b, defaultHigh_a, defaultHigh_b, defaultgre_x, defaultgre_y, defaultwhi_x, defaultwhi_y, defaultme_x, defaultme_y, true);
    } else {
   //     printf("RESET \n");
        setParams(0., 0., 0., 0., 0., 0., 0., 0., 0., 0., true);
    }
}


void LabGridArea::setEdited(bool yes)
{
    edited = yes;
}


bool LabGridArea::getEdited() const
{
    return edited;
}


void LabGridArea::setListener(ToolPanelListener *l)
{
    listener = l;
}


void LabGridArea::on_style_updated ()
{
    queue_draw ();
}


bool LabGridArea::on_draw(const ::Cairo::RefPtr<Cairo::Context> &cr)
{
    // Do not update drawing area if widget is not realized
    if (!get_realized()) {
        return true;
    }

    Glib::RefPtr<Gtk::StyleContext> style = get_style_context();
    Gtk::Border padding = getPadding(style);

    // Retrieve drawing area size
    Gtk::Allocation allocation = get_allocation();
    allocation.set_x(0);
    allocation.set_y(0);
    int width = allocation.get_width();
    int height = allocation.get_height();

    // Setup drawing
    cr->set_line_cap(Cairo::LINE_CAP_SQUARE);
    cr->set_operator (Cairo::OPERATOR_OVER);

    // Render background
    style->render_background(cr,
            static_cast<double>(inset + padding.get_left()) - 1.,
            static_cast<double>(inset + padding.get_top()) - 1.,
            static_cast<double>(width - 2 * inset - padding.get_right() - padding.get_left()) + 2.,
            static_cast<double>(height - 2 * inset - padding.get_top() - padding.get_bottom()) + 2.
            );

    // Drawing the cells
    cr->translate(static_cast<double>(inset + padding.get_left()),
        static_cast<double>(inset + padding.get_top()));
    cr->set_antialias(Cairo::ANTIALIAS_NONE);
    width -= 2 * inset + padding.get_right() + padding.get_left();
    height -= 2 * inset + padding.get_top() + padding.get_bottom();

    // flip y:
    cr->translate(0., static_cast<double>(height));
    cr->scale(1., -1.);

    if (! ciexy_enabled) {//draw cells for Labgrid
        const int cells = 8;
        const float step = 12000.f / static_cast<float>(cells/2);
        const double cellW = static_cast<double>(width) / static_cast<double>(cells);
        const double cellH = static_cast<double>(height) / static_cast<double>(cells);
        double cellYMin = 0.;
        double cellYMax = std::floor(cellH);
        for (int j = 0; j < cells; j++) {
            double cellXMin = 0.;
            double cellXMax = std::floor(cellW);
            for (int i = 0; i < cells; i++) {
                float R, G, B;
                float x, y, z;
                const int ii = i - cells/2;
                const int jj = j - cells/2;
                const float a = step * static_cast<float>(ii + 0.5f);
                const float b = step * static_cast<float>(jj + 0.5f);
                Color::Lab2XYZ(25000.f, a, b, x, y, z);
                Color::xyz2srgb(x, y, z, R, G, B);
                cr->set_source_rgb(R / 65535.f, G / 65535.f, B / 65535.f);
                cr->rectangle(
                        cellXMin,
                        cellYMin,
                        cellXMax - cellXMin - (i == cells-1 ? 0. : 1.),
                        cellYMax - cellYMin - (j == cells-1 ? 0. : 1.)
                        );
                cellXMin = cellXMax;
                cellXMax = std::floor(cellW * static_cast<double>(i+2) + 0.01);
                cr->fill();
            }
            cellYMin = cellYMax;
            cellYMax = std::floor(cellH * static_cast<double>(j+2) + 0.01);
        }
    } else {//cells for CIE xy
        const int cells = 600;
        const float step = 1.f / static_cast<float>(cells);
        const double cellW = static_cast<double>(width) / static_cast<double>(cells);
        const double cellH = static_cast<double>(height) / static_cast<double>(cells);
        double cellYMin = 0.;
        double cellYMax = std::floor(cellH);
        //various approximations to simulate Ciexy curves graph
        // this graph is not accurate...I replace curve by polygon or parabolic
        const float xa = 0.2653f / (0.7347f - 0.17f);
        const float xb = -0.17f * xa;
        //linear values
        const float axs = (0.2653f - 0.65f) / (0.7347f - 0.35f);
        const float bxs = 0.65f - axs * 0.35f;
        const float ay = 0.4f;
        const float by = 0.4f;
        for (int j = 0; j < cells; j++) {
            double cellXMin = 0.;
            double cellXMax = std::floor(cellW);
            for (int i = 0; i < cells; i++) {
                float R, G, B;
                float XX, YY, ZZ;
                const float x = 1.1f * step * static_cast<float>(i) - 0.1f;//Graph CIExy with -0.1 to 1 - must be enough
                const float y = 1.1f * step * static_cast<float>(j) - 0.1;//Graph CIExy with -0.1 to 1 - must be enough
                if(y > 0.5f) {
                    YY = 0.6f;
                } else {
                    YY = ay * y + by;
                }
                XX = (x * YY) / y;
                ZZ = ((1.f - x - y)* YY) / y;
                const float yr = xa * x + xb;
                const float y2 = axs * x + bxs;
                const float y6 = 22.52f * x * x - 7.652f * x + 0.65f;//parabolic passing in x=0.17 y=0 - x=0.1 y =0.11 - x=0 y= 0.65
                const float y3 = -1.266666f * x * x -0.170002f * x + 0.859686f;//other parabolic for green passing in x=0.35 y=0.65 - x=0.20 y=0.775 - x=0.1 y=0.83
                const float y4 = -60.71428f * x * x + 6.821428f * x + 0.65f;//other parabolic x=0 y=0.65 - x=0.03 y=0.8 - x=0.07 y=0.83
                //small difference  in the connection of the 2 last parabolic

                Color::xyz2srgb(XX, YY, ZZ, R, G, B);
                //replace color by gray
                if(y < yr && x > 0.17f) {
                    R = 0.7f; G = 0.7f; B = 0.7f;
                }
                if(y < y6 && y < 0.65f && x < 0.17f) {
                    R = 0.7f; G = 0.7f; B = 0.7f;
                }
                if(y > y2  && x > 0.35f) {//0.35
                    R = 0.7f; G = 0.7f; B = 0.7f;
                }
                if(y > y3  && x <= 0.35f && x > 0.06f) {//0.35
                    R = 0.7f; G = 0.7f; B = 0.7f;
                }
                if(y > y4  && x <= 0.06f) {
                    R = 0.7f; G = 0.7f; B = 0.7f;
                }

                cr->set_source_rgb(R , G , B);
                cr->rectangle(
                        cellXMin,
                        cellYMin,
                        cellXMax - cellXMin,
                        cellYMax - cellYMin);
                cellXMin = cellXMax;
                cellXMax = std::floor(cellW * static_cast<double>(i+2) + 0.001);
                cr->fill();
            }
            cellYMin = cellYMax;
            cellYMax = std::floor(cellH * static_cast<double>(j+2) + 0.001);
        }
    }

    // Drawing the connection line
    cr->set_antialias(Cairo::ANTIALIAS_DEFAULT);
   //     float loa, hia, lob, hib, grx, gry, whx, why, mex, mey;
    const double loa = .5 * (static_cast<double>(width) + static_cast<double>(width) * low_a);
    const double hia = .5 * (static_cast<double>(width) + static_cast<double>(width) * high_a);
    const double lob = .5 * (static_cast<double>(height) + static_cast<double>(height) * low_b);
    const double hib = .5 * (static_cast<double>(height) + static_cast<double>(height) * high_b);
    const double grx = .5 * (static_cast<double>(width) + static_cast<double>(width) * gre_x);
    const double gry = .5 * (static_cast<double>(height) + static_cast<double>(height) * gre_y);
    const double whx = .5 * (static_cast<double>(width) + static_cast<double>(width) * whi_x);
    const double why = .5 * (static_cast<double>(height) + static_cast<double>(height) * whi_y);
    double mex = .5 * (static_cast<double>(width) + static_cast<double>(width) * me_x);
    double mey = .5 * (static_cast<double>(height) + static_cast<double>(height) * me_y);
    cr->set_line_width(1.5);
        mex = .5 * (width + width * me_x);
        mey = .5 * (height + height * me_y);
    cr->set_source_rgb(0.6, 0.6, 0.6);
    cr->move_to(loa, lob);
    cr->line_to(hia, hib);
    if (ciexy_enabled) {
        cr->move_to(loa, lob);
        cr->line_to(grx, gry);
        cr->move_to(grx, gry);
        cr->line_to(hia, hib);
    }
    cr->stroke();

    if (ciexy_enabled) {
        cr->set_line_width(0.2);
        cr->set_source_rgb(0.1, 0.1, 0.1);
        //draw horiz and vertical lines
        for(int i = 0; i < 22; i++) {
            cr->move_to(0.04545 * static_cast<double>(i * width), 0.);
            cr->line_to(0.04545 * static_cast<double>(i * width), static_cast<double>(height));
        }
        for(int i = 0; i < 22; i++) {
            cr->move_to(0., 0.04545 * static_cast<double>(i * height));
            cr->line_to(static_cast<double>(width), 0.04545 * static_cast<double>(i * height));
        }

        cr->stroke();
        //draw abciss and ordonate
        cr->set_line_width(1.);
        cr->set_source_rgb(0.4, 0., 0.);
        cr->move_to(0.04545 * static_cast<double>(2 * width), 0.);
        cr->line_to(0.04545 * static_cast<double>(2 * width), static_cast<double>(height));
        cr->move_to(0., 0.04545 * static_cast<double>(2 * height));
        cr->line_to(static_cast<double>(width), 0.04545 * static_cast<double>(2 * height));
        cr->stroke();

        //draw 0 and 1 with circle and lines
        cr->set_line_width(1.2);
        cr->set_source_rgb(0.4, 0., 0.);
        cr->arc(0.06 * static_cast<double>(width),
            0.06 * static_cast<double>(height),
            0.016 * static_cast<double>(width),
            0.,
            2. * rtengine::RT_PI);
        cr->stroke();
        cr->set_line_width(1.5);
        cr->set_source_rgb(0.4, 0., 0.);
        cr->move_to(0.985 * static_cast<double>(width), 0.08 * static_cast<double>(height));
        cr->line_to(0.985 * static_cast<double>(width),  0.055 * static_cast<double>(height));

        cr->move_to(0.07 * static_cast<double>(width), 0.99 * static_cast<double>(height));
        cr->line_to(0.07 * static_cast<double>(width),  0.965 * static_cast<double>(height));

        cr->stroke();
    }

    // Drawing points
    if (low_enabled) {
        cr->set_source_rgb(0.1, 0.1, 0.1);//black for red in Ciexy
        if (litPoint == LOW) {
            cr->arc(loa, lob, 5., 0., 2. * rtengine::RT_PI);
        } else {
            cr->arc(loa, lob, 3., 0., 2. * rtengine::RT_PI);
        }
        cr->fill();
    }

    if (ciexy_enabled) {
        cr->set_source_rgb(0.5, 0.5, 0.5);//gray for green
        if (litPoint == GRE) {
            cr->arc(grx, gry, 5., 0., 2. * rtengine::RT_PI);
        } else {
            cr->arc(grx, gry, 3., 0., 2. * rtengine::RT_PI);
        }
        cr->fill();
    }

    if (ciexy_enabled) {//White Point
        cr->set_source_rgb(1., 1., 1.);//White
        cr->arc(whx, why, 3., 0., 2. * rtengine::RT_PI);
        cr->fill();
    }

        if (ciexy_enabled) {//Dominant
            cr->set_source_rgb(0.3, 0.4, 0.3);
            cr->arc(mex, mey, 3., 0, 2. * rtengine::RT_PI);
            cr->fill();
        }

    cr->set_source_rgb(0.9, 0.9, 0.9);//white for blue en Ciexy
    if (litPoint == HIGH) {
        cr->arc(hia, hib, 5., 0., 2. * rtengine::RT_PI);
    } else {
        cr->arc(hia, hib, 3., 0., 2. * rtengine::RT_PI);
    }
    cr->fill();

    return false;
}


bool LabGridArea::on_button_press_event(GdkEventButton *event)
{
    if (event->button == 1  && mous_enabled) {
      if (!ciexy_enabled) {
        if (event->type == GDK_2BUTTON_PRESS) {
            switch (litPoint) {
            case NONE:
                low_a = low_b = high_a = high_b = gre_x = gre_y = 0.f;
                break;
            case LOW:
                low_a = low_b = 0.f;
                break;
            case HIGH:
                high_a = high_b = 0.f;
                break;
            case GRE:
                gre_x = gre_y = 0.f;
                break;
            }
            edited = true;
            notifyListener();
            queue_draw();
        } else if (event->type == GDK_BUTTON_PRESS && litPoint != NONE) {
            isDragged = true;
        }
      } else {
        if(mous_enabled) {
            if (event->type == GDK_2BUTTON_PRESS) {
                edited = true;
                notifyListener();
                queue_draw();
            } else if (event->type == GDK_BUTTON_PRESS && litPoint != NONE) {
                isDragged = true;
            }
        }
      }
        return false;
    }
    return true;
}


bool LabGridArea::on_button_release_event(GdkEventButton *event)
{
    if (event->button == 1  && mous_enabled) {
        isDragged = false;
        return false;
    }
    return true;
}


bool LabGridArea::on_motion_notify_event(GdkEventMotion *event)
{
    if (isDragged && delayconn.connected()) {
        delayconn.disconnect();
    }

    Glib::RefPtr<Gtk::StyleContext> style = get_style_context();
    Gtk::Border padding = getPadding(style);  // already scaled

    State oldLitPoint = litPoint;

    const int width = get_allocated_width() - 2 * inset - padding.get_right() - padding.get_left();
    const int height = get_allocated_height() - 2 * inset - padding.get_top() - padding.get_bottom();
    const float mouse_x = std::min(double(std::max(event->x - inset - padding.get_right(), 0.)), double(width));
    const float mouse_y = std::min(double(std::max(get_allocated_height() - 1 - event->y - inset - padding.get_bottom(), 0.)), double(height));
    const float ma = (2.f * mouse_x - width) / width;
    const float mb = (2.f * mouse_y - height) / height;
    if (isDragged) {
        if (litPoint == LOW) {
            low_a = ma;
            low_b = mb;
        } else if (litPoint == HIGH) {
            high_a = ma;
            high_b = mb;
        } else if (litPoint == GRE) {
            gre_x = ma;
            gre_y = mb;
        }
        edited = true;
        grab_focus();
        if (options.adjusterMinDelay == 0) {
            notifyListener();
        } else {
            delayconn = Glib::signal_timeout().connect(sigc::mem_fun(*this, &LabGridArea::notifyListener), options.adjusterMinDelay);
        }
        queue_draw();
    } else {
        litPoint = NONE;
        const float la = low_a;
        const float lb = low_b;
        const float ha = high_a;
        const float hb = high_b;
        const float gx = gre_x;
        const float gy = gre_y;
        const float thrs = 0.05f;
        const float distlo = (la - ma) * (la - ma) + (lb - mb) * (lb - mb);
        const float disthi = (ha - ma) * (ha - ma) + (hb - mb) * (hb - mb);
        const float distgxy = (gx - ma) * (gx - ma) + (gy - mb) * (gy - mb);
        if (low_enabled && distlo < thrs * thrs && distlo < disthi) {
            litPoint = LOW;
        } else if (disthi < thrs * thrs && disthi <= distlo) {
            litPoint = HIGH;
        } else if (ciexy_enabled && distgxy < thrs * thrs && distgxy <= distlo) {
            litPoint = GRE;
        }
        if ((oldLitPoint == NONE && litPoint != NONE) || (oldLitPoint != NONE && litPoint == NONE)) {
            queue_draw();
        }
    }
    return true;
}


Gtk::SizeRequestMode LabGridArea::get_request_mode_vfunc() const
{
    return Gtk::SIZE_REQUEST_HEIGHT_FOR_WIDTH;
}


void LabGridArea::get_preferred_width_vfunc(int &minimum_width, int &natural_width) const
{
    Glib::RefPtr<Gtk::StyleContext> style = get_style_context();
    Gtk::Border padding = getPadding(style);  // already scaled
    const int s = RTScalable::scalePixelSize(1);
    const int p = padding.get_left() + padding.get_right();

    minimum_width = 50 * s + p;
    natural_width = 150 * s + p;  // same as GRAPH_SIZE from mycurve.h
}


void LabGridArea::get_preferred_height_for_width_vfunc(int width, int &minimum_height, int &natural_height) const
{
    Glib::RefPtr<Gtk::StyleContext> style = get_style_context();
    Gtk::Border padding = getPadding(style);  // already scaled

    minimum_height = natural_height = width - padding.get_left() - padding.get_right() + padding.get_top() + padding.get_bottom();
}


bool LabGridArea::lowEnabled() const
{
    return low_enabled;
}

bool LabGridArea::ciexyEnabled() const
{
    return ciexy_enabled;
}

void LabGridArea::setLowEnabled(bool yes)
{
    if (low_enabled != yes) {
        low_enabled = yes;
        queue_draw();
    }
}

void LabGridArea::setciexyEnabled(bool yes)
{
    if (ciexy_enabled != yes) {
        ciexy_enabled = yes;
        queue_draw();
    }
}

void LabGridArea::setmousEnabled(bool yes)
{
    if (mous_enabled != yes) {
        mous_enabled = yes;
        queue_draw();
    }
}


//-----------------------------------------------------------------------------
// LabGrid
//-----------------------------------------------------------------------------

LabGrid::LabGrid(rtengine::ProcEvent evt, const Glib::ustring &msg, bool enable_low, bool ciexy, bool mous):
    grid(evt, msg, enable_low, ciexy, mous)
{
    Gtk::Button *reset = Gtk::manage(new Gtk::Button());
    reset->set_tooltip_markup(M("ADJUSTER_RESET_TO_DEFAULT"));
    if(!ciexy) {//disabled for Cie xy
        reset->add(*Gtk::manage(new RTImage("undo-small", Gtk::ICON_SIZE_BUTTON)));
    }
    reset->signal_button_release_event().connect(sigc::mem_fun(*this, &LabGrid::resetPressed));

    setExpandAlignProperties(reset, false, false, Gtk::ALIGN_CENTER, Gtk::ALIGN_START);
    reset->set_relief(Gtk::RELIEF_NONE);
    reset->get_style_context()->add_class(GTK_STYLE_CLASS_FLAT);
    reset->set_can_focus(false);
    reset->set_size_request(-1, 20);

    pack_start(grid, true, true, true);
    pack_start(*reset, false, false);
    show_all_children();
}


bool LabGrid::resetPressed(GdkEventButton *event)
{
    grid.reset(event->state & GDK_CONTROL_MASK);
    return false;
}