<snapdata remixID="8923798"><project name="U2L4-checkerboard_SV" app="Snap! 5.1, http://snap.berkeley.edu" 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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="-189.76457135307555" y="-171.7645713530756" heading="180" scale="1" volume="100" pan="0" rotation="1" draggable="true" costume="0" color="255,47,31,1" 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="23" y="10"><block s="clear"></block></script><script x="135" y="381"><custom-block s="draw brick wall %s rows"><l></l></custom-block></script><script x="77" y="120.99999999999989"><block s="up"></block></script><script x="156" y="35.99999999999994"><block s="down"></block></script><script x="205.999999" y="76.99999899999989"><block s="doRepeat"><l>4</l><script><block s="forward"><l>1</l></block><custom-block s="draw black square size %n"><l>40</l></custom-block><block s="doWait"><l>1</l></block><block s="forward"><l>1</l></block><custom-block s="draw red square size %n"><l>40</l></custom-block></script></block></script><script x="218.999999" y="242.9999989999999"><block s="turnLeft"><l>90</l></block></script><script x="221.999999" y="298.9999989999999"><block s="doRepeat"><l>4</l><script><block s="forward"><l>1</l></block><custom-block s="draw black square size %n"><l>40</l></custom-block><block s="doWait"><l>1</l></block><block s="forward"><l>1</l></block><custom-block s="draw red square size %n"><l>40</l></custom-block></script></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 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type="%n"></input></inputs><script><block s="setColor"><color>255,47,31,1</color></block><custom-block s="set flat line ends to %b"><block s="reportBoolean"><l><bool>true</bool></l></block></custom-block><block s="setSize"><block var="size"/></block><block s="down"></block><block s="forward"><block var="size"/></block><block s="up"></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 s="setColor"><color>145,26,68,1</color></block><custom-block s="set flat line ends to %b"><block s="reportBoolean"><l><bool>true</bool></l></block></custom-block><block s="setSize"><block var="width"/></block><block s="down"></block><block s="forward"><block var="length"/></block><block s="up"></block></script></block-definition><block-definition s="row a" 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s="gotoXY"><l>0</l><block var="y value"/></block></script></scripts></block-definition><block-definition s="draw checker board" type="command" category="pen"><header></header><code></code><translations></translations><inputs></inputs></block-definition></blocks><variables></variables></project><media name="U2L4-checkerboard_SV" app="Snap! 5.1, http://snap.berkeley.edu" version="1"></media></snapdata>