var displayClass = {

    new: func(node, role) {

        var m = { parents: [ displayClass ] };

        m.display = canvas.new({

                "name"      : role,

                "size"      : [1024, 768],

                "view"      : [1024, 768],

                "mipmapping": 1

        });

        m.display.addPlacement({

                "node": "Screen",

                "parent": role

        });

        m.display.setColorBackground(0,0,0);

        m.role = role;

        m.screenElements = {};

        return m;

    },

    loadsvg : func () {

        me.screen = me.display.createGroup();

        me.screen.hide();

        canvas.parsesvg(me.screen, "Aircraft/Instruments-3d/zkv1000/Systems/screen.svg");

    },

    _showInitProgress : func (p,t) {

        p.setText(t);

        if (zkv.getNode(me.role ~ 'init').getValue() != 0) {

            if (size(t) >= 10) t = '';

            settimer(func { me._showInitProgress(p, t ~ '.'); }, 0.1);

        }

        else {

            me.progress.hide();

            me.screen.show();

            me.loadGroup({

                show : [

                    'SoftKeysTexts', 

                    'COMM', 

                    'NAV', 

                    'XPDR-TIME', 

                    'FlightInstruments',

                    'Horizon',

                    'bankPointer',

                    'VSI',

                ],

                text: [

                    'VSIText',

                    'Speed110',

                    'Alt11100'

                ],

                clip: [

                    'SpeedLint1',

                    'SpeedTape',

                    'LintAlt',

                    'AltLint00011'

                ],

            });

            var AltBigAltSmall = [ 'AltBigC', 'AltSmallC' ];

            for (var place = 1; place <= 6; place +=1) {

                append(AltBigAltSmall,

                    'AltBigU' ~ place,

                    'AltSmallU' ~ place,

                    'AltBigD' ~ place,

                    'AltSmallD' ~ place

                );

            }

            me.loadGroup({text: AltBigAltSmall});

            me.updateAI(getprop('/orientation/roll-deg'),getprop('orientation/pitch-deg'));

            me.updateVSI(getprop('/instrumentation/vertical-speed-indicator/indicated-speed-fpm'));

            me.updateIAS(getprop('/velocities/airspeed-kt'));

            me.updateALT(getprop('instrumentation/altimeter/indicated-altitude-ft'));

            me.progress.removeAllChildren();

            me.progress = nil;

            me.showInitProgress = nil;

            me._showInitProgress = nil;

            zkv.removeChild(me.role ~ 'init');

        }

    },

    showInitProgress : func (role) {

        me.progress = me.display.createGroup();

        me.progress.show();

        me.progress.createChild("text", role ~ " title")

            .setTranslation(512, 384)

            .setAlignment("center-center")

            .setFont("LiberationFonts/LiberationSans-Italic.ttf")

            .setFontSize(64, 1)

            .setColor(1,1,1)

            .setText("ZKV1000 " ~ role ~ " init");

        zkv.getNode(role ~ 'init',1).setIntValue(1);

        me._showInitProgress(me.progress.createChild("text", role ~ "progress")

            .setTranslation(512, 484)

            .setAlignment("center-center")

            .setFont("LiberationFonts/LiberationSans-Bold.ttf")

            .setFontSize(128, 1)

            .setColor(1,0,0), '.');

    },

    loadGroup : func (h) {

        if (typeof(h) != 'hash') {

            msg_dbg(sprintf("%s need a hash, but get a %s from %s",

                    caller(0)[0],

                    typeof(h),

                    caller(1)[0]));

            return;

        }

        var setMethod = func (e, t) {

            if (t == 'hide')

                me.screenElements[e].hide();

            elsif (t == 'show')

                me.screenElements[e].show();

            elsif (t == 'rot' or t == 'trans') {

                if (! contains(me.screenElements[e], t))

                    me.screenElements[e][t] = me.screenElements[e].createTransform();

            }

            elsif (t == 'clip') {

                if (contains(me.clips, e))

                    me.screenElements[e].set("clip", me.clips[e]);

                else

                    print('no defined clip for ' ~ e);

            }

            elsif (t == 'text') {

                if (contains(me.texts, e)) {

                    if (contains(me.texts[e], 'alignment'))

                        me.screenElements[e].setAlignment(me.texts[e].alignment);

                    if (contains(me.texts[e], 'default'))

                        me.screenElements[e].setText(me.texts[e].default);

                }

                else

                    print('no alignment for ' ~ e);

            }

            else

                print('unknown method ' ~ t);

        };

        foreach (var todo; keys(h)) {

            if (typeof(h[todo]) != 'vector') h[todo] = [ h[todo] ];

            foreach (var id; h[todo]) {

                if (! contains(me.screenElements, id)) {

                    me.screenElements[id] = me.screen.getElementById(id);

                    if (me.screenElements[id] != nil)

                        setMethod(id, todo);

                    else

                        print('SVG ID ' ~ id ~ ' not found');

                }

                else

                    setMethod(id, todo);

            }

        }

    },

    clips : {

        PitchScale : "rect(70,664,370,256)",

        SpeedLint1 : "rect(252,226,318,204)",

        SpeedTape : "rect(115,239,455,156)",

        LintAlt : "rect(115,808,455,704)",

        AltLint00011 : "rect(252,804,318,771)",

    },

    texts : {

        VSIText : {

            alignment: "right-bottom", default : num('0'),

        },

        Speed110 : {

            default: '', alignment : 'left-bottom'

        },

        Alt11100 : {

            default:'', alignment:'left-bottom'

        },

    },

    updateAI: func(roll,pitch){

        if (pitch > 80)

            pitch = 80;

        elsif(pitch < -80)

            pitch = -80;

        me.screenElements.Horizon

            .setRotation(-roll * D2R)

            .setTranslation(0, pitch * 6.8571428);

        me.screenElements.bankPointer

            .setRotation(-roll * D2R);

        settimer(func me.updateAI(getprop('/orientation/roll-deg'),getprop('orientation/pitch-deg')), 0.1);

    },

    updateVSI: func (vsi) {

        me.screenElements.VSIText

            .setText(num(math.round(vsi, 10)));

        if (vsi > 4500)

            vsi = 4500;

        elsif (vsi < -4500)

            vsi = -4500;

        me.screenElements.VSI

            .setTranslation(0, vsi * -0.03465);

        settimer(func me.updateVSI(getprop('/instrumentation/vertical-speed-indicator/indicated-speed-fpm')), 0.1);

    },

    updateIAS: func (ias) {

        if (ias >= 10)

            me.screenElements.Speed110

                .setText(sprintf("% 2u",num(math.floor(ias/10))));

        else

            me.screenElements.Speed110

                .setText('');

        me.screenElements.SpeedLint1

            .setTranslation(0,(math.mod(ias,10) + (ias >= 10)*10) * 36);

        me.screenElements.SpeedTape

            .setTranslation(0,ias * 5.711);

        settimer(func me.updateIAS(getprop('/velocities/airspeed-kt')), 0.1);

    },

    updateALT: func (alt) {

        if (alt < 0)

            me.screenElements.Alt11100

                .setText(sprintf("% 3i",math.ceil(alt/100)));

        elsif (alt < 100)

            me.screenElements.Alt11100

                .setText('');

        else

            me.screenElements.Alt11100

                .setText(sprintf("% 3i",math.floor(alt/100)));

        me.screenElements.AltLint00011

            .setTranslation(0,math.fmod(alt,100) * 1.24);

        # From Farmin/G1000 http://wiki.flightgear.org/Project_Farmin/FG1000

        if (alt> -1000 and alt< 1000000) {

            var Offset10 = 0;

            var Offset100 = 0;

            var Offset1000 = 0;

            if (alt< 0) {

                var Ne = 1;

                var alt= -alt;

            }

            else

                var Ne = 0;

            var Alt10       = math.mod(alt,100);

            var Alt100      = int(math.mod(alt/100,10));

            var Alt1000     = int(math.mod(alt/1000,10));

            var Alt10000    = int(math.mod(alt/10000,10));

            var Alt20       = math.mod(Alt10,20)/20;

            if (Alt10 >= 80)

                var Alt100 += Alt20;

            if (Alt10 >= 80 and Alt100 >= 9)

                var Alt1000 += Alt20;

            if (Alt10 >= 80 and Alt100 >= 9 and Alt1000 >= 9)

                var Alt10000 += Alt20;

            if (alt> 100)

                var Offset10 = 100;

            if (alt> 1000)

                var Offset100 = 10;

            if (alt> 10000)

                var Offset1000 = 10;

            if (!Ne) {

                me.screenElements.LintAlt.setTranslation(0,(math.mod(alt,100))*0.57375);

                var altCentral = (int(alt/100)*100);

            }

            elsif (Ne) {

                me.screenElements.LintAlt.setTranslation(0,(math.mod(alt,100))*-0.57375);

                var altCentral = -(int(alt/100)*100);

            }

            me.screenElements["AltBigC"].setText("");

            me.screenElements["AltSmallC"].setText("");

            for (var place = 1; place <= 6; place += 1) {

                var altUP = altCentral + (place*100);

                var offset = -30.078;

                if (altUP < 0) {

                    var altUP = -altUP;

                    var prefix = "-";

                    var offset += 15.039;

                }

                else

                    var prefix = "";

                if (altUP == 0) {

                    var AltBigUP    = "";

                    var AltSmallUP  = "0";

                }

                elsif (math.mod(altUP,500) == 0 and altUP != 0) {

                    var AltBigUP    = sprintf(prefix~"%1d", altUP);

                    var AltSmallUP  = "";

                }

                elsif (altUP < 1000 and (math.mod(altUP,500))) {

                    var AltBigUP    = "";

                    var AltSmallUP  = sprintf(prefix~"%1d", int(math.mod(altUP,1000)));

                    var offset = -30.078;

                }

                elsif ((altUP < 10000) and (altUP >= 1000) and (math.mod(altUP,500))) {

                    var AltBigUP    = sprintf(prefix~"%1d", int(altUP/1000));

                    var AltSmallUP  = sprintf("%1d", int(math.mod(altUP,1000)));

                    var offset += 15.039;

                }

                else {

                    var AltBigUP    = sprintf(prefix~"%1d", int(altUP/1000));

                    var mod = int(math.mod(altUP,1000));

                    var AltSmallUP  = sprintf("%1d", mod);

                    var offset += 30.078;

                }

                me.screenElements["AltBigU"~place].setText(AltBigUP);

                me.screenElements["AltSmallU"~place].setText(AltSmallUP);

                me.screenElements["AltSmallU"~place].setTranslation(offset,0);

                var altDOWN = altCentral - (place*100);

                var offset = -30.078;

                if (altDOWN < 0) {

                    var altDOWN = -altDOWN;

                    var prefix = "-";

                    var offset += 15.039;

                }

                else

                    var prefix = "";

                if (altDOWN == 0) {

                    var AltBigDOWN  = "";

                    var AltSmallDOWN    = "0";

                }

                elsif (math.mod(altDOWN,500) == 0 and altDOWN != 0) {

                    var AltBigDOWN  = sprintf(prefix~"%1d", altDOWN);

                    var AltSmallDOWN    = "";

                }

                elsif (altDOWN < 1000 and (math.mod(altDOWN,500))) {

                    var AltBigDOWN  = "";

                    var AltSmallDOWN    = sprintf(prefix~"%1d", int(math.mod(altDOWN,1000)));

                    var offset = -30.078;

                }

                elsif ((altDOWN < 10000) and (altDOWN >= 1000) and (math.mod(altDOWN,500))) {

                    var AltBigDOWN  = sprintf(prefix~"%1d", int(altDOWN/1000));

                    var AltSmallDOWN    = sprintf("%1d", int(math.mod(altDOWN,1000)));

                    var offset += 15.039;

                }

                else {

                    var AltBigDOWN  = sprintf(prefix~"%1d", int(altDOWN/1000));

                    var mod = int(math.mod(altDOWN,1000));

                    var AltSmallDOWN    = sprintf("%1d", mod);

                    var offset += 30.078;

                }

                me.screenElements["AltBigD"~place].setText(AltBigDOWN);

                me.screenElements["AltSmallD"~place].setText(AltSmallDOWN);

                me.screenElements["AltSmallD"~place].setTranslation(offset,0);

            }

        }

        settimer(func me.updateALT(getprop('instrumentation/altimeter/indicated-altitude-ft')), 0.2);

    },

};