<snapdata remixID="8923107"><project name="U2L4-checkerboard_SV" app="Snap! 5.1, http://snap.berkeley.edu" version="1"><notes></notes><thumbnail>data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAKAAAAB4CAYAAAB1ovlvAAAFMklEQVR4Xu2cy2oUQRSGazDOTPAhdO1CAoIL8VEUQRCfRkQhRCEKQV/DxIW40HhZZW2eIhCUkWSgu6anunP67+lTY8/nUqun7FPf+c+lqno0m81mgT9YIJMFRgCYyfJMe2kBAASErBbwB3DnlvTC2yenrZ87u32z9TPKPBeTeM2lzHPx/1Pe6+y8/+wMACuIKgsFgK39vHgAAAGwlh4UMDKNokxKuFLmQQFRwKQFALA0y4Jjja6F/XcH4e+f8/Ds6RMU0OI/ijIBYBrAh48ehw/vD4p/HE9vhOPvP8Pb/Tfh5Yvnxd8TggnBS76pOFWqCv785Wt4cP/e0u9vbV0Pd3buhsOjT2EymVi0odMYipANLUKuAvDj4VGYTqed4LI8DIAbCGAqBH87/hH2dl+F13u7hOCU55ADzq2ykhBMEWIR58UxALhCAI3mpwihCOmtCLEwCIAACIAWT2k1hsMIhbm80opUG8ayZoNUwO3xyPLuK/H8tV/gNT+tE379ltaqzUPubRgALJdHqWgVp5KrZwD0XywFCjnEoYD+J6JRQH+nQgHjapYcsNxpQAFRwGrCTAiOLEIO6B+uABAAk1W8AoZSMSrzUIS0abwsjqUNU7EdAKKAKGCDoCiqThVMFZzVqQAQAAGwRtXJAckB6wP+ENswgdMwxYIr+ZxrkcSnOUrn9FosZR41x1LmAkC95TN/EgVEASOG3HNAAPRXdblRTgj2XywlLBKC9bCIAlZsB4ClQQZ5JJ8Q7K/qhOBYZShCKEIoQupzFkIwIThJhwKG0jNT5qEIoQj5L/daFdgVpyIHJAfMquoACIAAWBOl3fuAXMuMknxuxXErruqYrjkWAAIgADZUsEM8D0gIJgTHyJMDVgSAEBwZBAX0VwsABMCsTWUABEAAbKgLlN0TdauQD1RGC6Eok7JYyjzyTgNtGNowtGFow5iOUijKhAJ2K+IIwYTgJedUnIocMDIjjehuqgSApoBZPwgAATDrTgiXkkrzK2qm5MJylc69YP/FUqBQcyxlLgDsGIJRQH+nQgFjaLmWWVgDBQz+jWgUEAWkCFmTvVYUEAXM2ugFQAAEwIZowMeJ4h2Uk9PW9bfSslBUiTZM66UpHnA/kk8RQhFCEUIRYpIsQjAheAkUJa2gEU0jOqk4Sr4JgCbxrh/EaZjSNgpMCrRqkcSB1Ihjr8VS5pFDHHdC/LfiUEAUMGsVDIAACIBN3X8hLBKC9cLAvRGNAqKAKCAKaJMsPk7krxZUwRGbAAiAVamiD2gT79pR5ID+TkUjOt7THY8khJXQqKiFMg9VsLSklw9RBVdsB4DkgEl3UsBAAbuF+0HuBXMgtYRi7R2ELyP4L5YChZrkK3MpkUDOUQEQAKv5CADqBc/8Sb6MUFgQBcxQBQOgv6oTgmPVRAFRwIgH9z4gCogCxnoEgJWcVsnLqIL1wgAAAbCWHu4FR6ZRlElpWSjzoIAoYNbtOwAEQAC8ggFF2QnBhOAlrJS0gj4gfcCkPkmq5Hlrb4h7wZyILllU1EyBVs1RB3kcCwABMGsjGgABEAAbKkYlLMpJvpDPEYL1ls/lkyggCogCooA2GeFiur9aEIIjNgEQAKtSRQ5oE+/aUeSA/k5FHzDeUuPLCIU1lHCPAqKAWbfVABAAAbAjA7RhaMPYEBpiFWx7c0ZtigX874RsimV5T5MFANBkJgb1ZQEA7Muy/K7JAgBoMhOD+rIAAPZlWX7XZAEANJmJQX1ZAAD7siy/a7IAAJrMxKC+LACAfVmW3zVZ4B8AWXMCJrdUvgAAAABJRU5ErkJggg==</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="165" y="150" 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="22" y="49"><block s="receiveGo"></block><block s="clear"></block><custom-block s="Draw Checkboard"></custom-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 Checkboard" type="command" category="pen"><header></header><code></code><translations></translations><inputs></inputs><script><block s="doDeclareVariables"><list><l>y value</l></list></block><block s="doSetVar"><l>y value</l><l>40</l></block><block s="gotoXY"><l>-155</l><l>-170</l></block><block s="doRepeat"><l>4</l><script><custom-block s="Change The Y Value of Rows by %n"><block var="y value"/></custom-block><custom-block s="Row A"></custom-block><custom-block s="Change The Y Value of Rows by %n"><block var="y value"/></custom-block><custom-block s="Row B"></custom-block></script></block></script></block-definition><block-definition s="Row A" type="command" category="pen"><header></header><code></code><translations></translations><inputs></inputs><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></script></block-definition><block-definition s="Row B" type="command" category="pen"><header></header><code></code><translations></translations><inputs></inputs><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></script></block-definition><block-definition s="Change The Y Value of Rows by %&apos;y value&apos;" type="command" category="motion"><header></header><code></code><translations></translations><inputs><input type="%n"></input></inputs><script><block s="setXPosition"><l>-155</l></block><block s="changeYPosition"><block var="y value"/></block></script></block-definition></blocks><variables></variables></project><media name="U2L4-checkerboard_SV" app="Snap! 5.1, http://snap.berkeley.edu" version="1"></media></snapdata>