<snapdata remixID="8923835"><project name="U2L4-checkerboard_SV" app="Snap! 5.1, http://snap.berkeley.edu" version="1"><notes></notes><thumbnail>data:image/png;base64,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</thumbnail><stage 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" id="1"><pentrails>data:image/png;base64,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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="-200" y="170" heading="90" 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="121.999998" y="107.99999900000017"><block s="clear"></block><block s="gotoXY"><l>-200</l><l>-150</l></block><block s="setHeading"><l>90</l></block><block s="doRepeat"><l>4</l><script><block s="doRepeat"><l>4</l><script><custom-block s="draw black square size %n"><l>40</l></custom-block><custom-block s="draw red square size %n"><l>40</l></custom-block></script></block><block s="setHeading"><l>0</l></block><block s="forward"><l>40</l></block><block s="turnLeft"><l>90</l></block><block s="doRepeat"><l>4</l><script><custom-block s="draw black square size %n"><l>40</l></custom-block><custom-block s="draw red square size %n"><l>40</l></custom-block></script></block><block s="setHeading"><l>0</l></block><block s="forward"><l>40</l></block><block s="turn"><l>90</l></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;      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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 s="setColor"><color>145,26,68,1</color></block><custom-block s="set flat line 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