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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="-190" y="-190" heading="90" 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="12" y="17.19999999999999"><block s="clear"></block><block s="gotoXY"><l>-190</l><l>130</l></block><block s="doRepeat"><l>4</l><script><block s="doRepeat"><l>4</l><script><custom-block s="draw red square size %n"><l>40</l></custom-block><custom-block s="draw black square size %n"><l>40</l></custom-block></script></block><block s="changeYPosition"><l>-40</l></block><block s="turnLeft"><l>180</l></block><block s="doRepeat"><l>4</l><script><custom-block s="draw red square size %n"><l>40</l></custom-block><custom-block s="draw black square size %n"><l>40</l></custom-block></script></block><block s="changeYPosition"><l>-40</l></block><block s="turnLeft"><l>180</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;            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 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="set flat line ends to %&apos;flag&apos;" type="command" category="pen"><header></header><code></code><translations></translations><inputs><input type="%b"></input></inputs><script><custom-block s="set flag %s to %b"><l>Flat line ends</l><block var="flag"/></custom-block></script></block-definition><block-definition s="draw black square size %&apos;size&apos;" type="command" category="pen"><header></header><code></code><translations></translations><inputs><input type="%n"></input></inputs><script><block s="setColor"><color>8,5,0,1</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 red square size %&apos;size&apos;" type="command" category="pen"><header></header><code></code><translations></translations><inputs><input 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 checkerboard" 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>