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name="Stage" width="480" height="360" costume="0" color="255,255,255,1" tempo="60" threadsafe="false" volume="100" pan="0" lines="flat" ternary="true" codify="false" inheritance="false" sublistIDs="false" scheduled="false" 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</pentrails><costumes><list struct="atomic" id="2"></list></costumes><sounds><list struct="atomic" id="3"></list></sounds><variables></variables><blocks></blocks><scripts></scripts><sprites><sprite name="Sprite" idx="1" x="15" y="0" heading="345" scale="1" volume="100" pan="0" rotation="1" draggable="true" costume="0" color="8,5,0,1" pen="tip" id="8"><costumes><list struct="atomic" id="9"></list></costumes><sounds><list struct="atomic" id="10"></list></sounds><blocks></blocks><variables></variables><scripts><script x="217" y="116"><custom-block s="draw checkerboard"></custom-block></script><script x="37" y="165"><block s="doDeclareVariables"><list><l>y value</l><l>row</l></list></block><block s="doSetVar"><l>y value</l><l>0</l></block><block s="doFor"><l>row</l><l>1</l><l>8</l><script><block s="gotoXY"><l>0</l><block var="y value"/></block></script></block></script><script x="17" y="313"><block s="gotoXY"><l>0</l><l>0</l></block></script><script x="94" y="368"><block s="gotoXY"><l>15</l><l>15</l></block></script><script x="254" y="308"><block s="gotoXY"><l>30</l><l>30</l></block></script><script x="220" y="243"><block s="gotoXY"><l>45</l><l>45</l></block></script><script x="365" y="383"><block s="gotoXY"><l>15</l><l>15</l></block></script><script x="369" y="240"><block s="gotoXY"><l>15</l><l>15</l></block></script></scripts></sprite></sprites></stage><hidden></hidden><headers></headers><code></code><blocks><block-definition s="set flag %&apos;which&apos; to %&apos;tf&apos;" type="command" category="sensing"><header></header><code></code><translations></translations><inputs><input type="%s" readonly="true"><options>Presentation mode&#xD;Retina display support&#xD;Long form input dialog&#xD;Plain prototype labels&#xD;Input sliders&#xD;Execute on slider change&#xD;Clicking sound&#xD;Turbo mode&#xD;Flat design&#xD;Keyboard editing&#xD;Table support&#xD;Table lines&#xD;Visible stepping&#xD;Thread safe scripts&#xD;Prefer smooth animations&#xD;Flat line ends&#xD;Codification support&#xD;Inheritance support</options></input><input type="%b"></input></inputs><script><block s="doRun"><block s="reportJSFunction"><list><l>which</l><l>tf</l></list><l>var   stage = this.parentThatIsA(StageMorph),&#xD;        ide = stage.parentThatIsA(IDE_Morph),&#xD;        world = stage.parentThatIsA(WorldMorph);&#xD;&#xD;if (tf != !!tf) return;&#xD;&#xD;try{&#xD;ide.savingPreferences = false;&#xD;&#xD;switch (which) {&#xD;    case &apos;Presentation mode&apos;:&#xD;        if (tf != ide.isAppMode) ide.toggleAppMode();&#xD;        break;&#xD;    case &apos;Retina display support&apos;:&#xD;        if (tf != isRetinaEnabled()) ide.toggleRetina();&#xD;        break;&#xD;    case &apos;Long form input dialog&apos;:&#xD;        if (tf != InputSlotDialogMorph.prototype.isLaunchingExpanded)&#xD;            ide.toggleLongFormInputDialog();&#xD;        break;&#xD;    case &apos;Plain prototype labels&apos;:&#xD;        if (tf != BlockLabelPlaceHolderMorph.prototype.plainLabel)&#xD;            ide.togglePlainPrototypeLabels();&#xD;        break;&#xD;    case &apos;Input sliders&apos;:&#xD;        MorphicPreferences.useSliderForInput = tf;&#xD;        break;&#xD;    case &apos;Execute on slider change&apos;:&#xD;        ArgMorph.prototype.executeOnSliderEdit = tf;&#xD;        break;&#xD;    case &apos;Clicking sound&apos;:&#xD;        if (tf != !!BlockMorph.prototype.snapSound)&#xD;            BlockMorph.prototype.toggleSnapSound();&#xD;        break;&#xD;    case &apos;Turbo mode&apos;:&#xD;        if (tf != stage.isFastTracked)&#xD;            ide.toggleFastTracking();&#xD;        break;&#xD;    case &apos;Flat design&apos;:&#xD;        if (tf == MorphicPreferences.isFlat) break;&#xD;        if (tf)&#xD;            ide.flatDesign();&#xD;        else&#xD;            ide.defaultDesign();&#xD;        break;&#xD;    case &apos;Keyboard editing&apos;:&#xD;            ScriptsMorph.prototype.enableKeyboard = tf;&#xD;        break;&#xD;    case &apos;Table support&apos;:&#xD;            List.prototype.enableTables = tf;&#xD;        break;&#xD;    case &apos;Table lines&apos;:&#xD;                TableMorph.prototype.highContrast = tf;&#xD;        break;&#xD;    case &apos;Visible stepping&apos;:&#xD;        if (tf != Process.prototype.enableSingleStepping)&#xD;            ide.toggleSingleStepping();&#xD;        break;&#xD;    case &apos;Thread safe scripts&apos;:&#xD;        stage.isThreadSafe = tf;&#xD;        break;&#xD;    case &apos;Prefer smooth animations&apos;:&#xD;        if (tf != (StageMorph.prototype.frameRate &gt; 0))&#xD;            ide.toggleVariableFrameRate();&#xD;        break;&#xD;    case &apos;Flat line ends&apos;:&#xD;        SpriteMorph.prototype.useFlatLineEnds = tf;&#xD;        break;&#xD;    case &apos;Codification support&apos;:&#xD;        if (tf != StageMorph.prototype.enableCodeMapping) {&#xD;            StageMorph.prototype.enableCodeMapping = tf;&#xD;            ide.currentSprite.blocksCache.variables = null;&#xD;            ide.currentSprite.paletteCache.variables = null;&#xD;            ide.refreshPalette();&#xD;        }&#xD;        break;&#xD;    case &apos;Inheritance support&apos;:&#xD;        if (tf != StageMorph.prototype.enableInheritance) {&#xD;            StageMorph.prototype.enableInheritance = tf;&#xD;            ide.currentSprite.blocksCache.variables = null;&#xD;            ide.currentSprite.paletteCache.variables = null;&#xD;            ide.refreshPalette();&#xD;        }&#xD;        break;&#xD;};&#xD;}&#xD;finally {&#xD;ide.savingPreferences = false;&#xD;};&#xD;</l></block><list><block var="which"/><block var="tf"/></list></block></script></block-definition><block-definition s="draw brick, length: %&apos;length&apos; width: %&apos;width&apos;" type="command" category="pen"><header></header><code></code><translations></translations><inputs><input type="%n"></input><input type="%n"></input></inputs><script><block 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