<snapdata remixID="8923795"><project name="U2L4-checkerboard_SV" app="Snap! 4.2, http://snap.berkeley.edu" 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name="Stage" width="480" height="360" costume="0" tempo="60" threadsafe="false" lines="flat" ternary="true" codify="false" inheritance="false" sublistIDs="false" scheduled="false" 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id="2"></list></costumes><sounds><list id="3"></list></sounds><variables></variables><blocks></blocks><scripts></scripts><sprites><sprite name="Sprite" idx="1" x="200" y="-95" heading="90" scale="1" rotation="1" draggable="true" costume="0" color="255,47,31" pen="tip" id="8"><costumes><list id="9"></list></costumes><sounds><list id="10"></list></sounds><blocks></blocks><variables></variables><scripts><script x="225" y="52"><block s="clear"></block></script><script x="10" y="531"><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><script x="247" y="535"><block s="doGlide"><l>1</l><l>-200</l><l>-90</l></block></script><script x="522.5498056875" y="177.000001"><block var="y value"/></script><script x="436.000001" y="416.000001"><block s="doRepeat"><l>10</l><script></script></block></script><script x="31" y="68"><block s="doGlide"><l>1</l><l>-200</l><l>-150</l></block><block s="doRepeat"><l>7</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="doGlide"><l>1</l><l>-200</l><l>-135</l></block><block s="doRepeat"><l>7</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="doGlide"><l>1</l><l>-200</l><l>-125</l></block><block s="doRepeat"><l>7</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="doGlide"><l>1</l><l>-200</l><l>-110</l></block><block s="doRepeat"><l>7</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="doGlide"><l>1</l><l>-200</l><l>-95</l></block><block s="doRepeat"><l>7</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></script><script x="330" y="29"><block s="receiveGo"></block><block s="doDeclareVariables"><list><l>y value</l></list></block><block s="doSetVar"><l>y value</l><l>-150</l></block><block s="doRepeat"><l>4</l><script><block s="doGlide"><l>1</l><l>-200</l><block var="y value"/></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="doChangeVar"><l>y value</l><l>40</l></block><block s="doGlide"><l>1</l><l>-200</l><block var="y value"/></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="doChangeVar"><l>y value</l><l>40</l></block></script></block></script></scripts></sprite><watcher var="y" style="normal" x="10" y="10" color="243,118,29" hidden="true"/></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
Retina display support
Long form input dialog
Plain prototype labels
Input sliders
Execute on slider change
Clicking sound
Turbo mode
Flat design
Keyboard editing
Table support
Table lines
Visible stepping
Thread safe scripts
Prefer smooth animations
Flat line ends
Codification support
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="create checkerboard" type="command" category="pen"><header></header><code></code><translations></translations><inputs></inputs></block-definition></blocks><variables><variable name="y"><l>0</l></variable></variables></project><media name="U2L4-checkerboard_SV" app="Snap! 4.2, http://snap.berkeley.edu" version="1"></media></snapdata>