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POUnderstanding Array Access (Processing)
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  1. POUnderstanding Array Access (Processing)
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    copied!<p>Hi could anybody help me understand this particular piece of code from this Langton's Ant sketch.</p> <pre><code>antLoc = new int[]{rows/2,columns/2}; </code></pre> <p>I don't exactly understand what is actually happening here, here is the rest of the code for context. (originally from here <a href="http://www.openprocessing.org/visuals/?visualID=13653" rel="nofollow">http://www.openprocessing.org/visuals/?visualID=13653</a>) </p> <pre><code>boolean[][] state; int[] antLoc; int antDirection; int squareSize = 5; int columns, rows; color bgCol = color(0,128,128); color antCol = color (255,0,0); color sqCol = color(128,128,128); void setup(){ size(800,600); background(bgCol); columns = width/squareSize; rows = height/squareSize; state = new boolean[rows][columns]; for(int j = 0; j &lt; rows; j++){ for(int i = 0; i &lt; columns; i++){ state[j][i] = false; } } antLoc = new int[]{rows/2,columns/2}; antDirection = 1; } void drawScene(){ fill(sqCol); for(int j = 0; j &lt; rows; j++){ for(int i = 0; i &lt; columns; i++){ if(state[j][i]){ rect(i*squareSize,j*squareSize,squareSize,squareSize); } } } fill(antCol); rect(antLoc[1]*squareSize,antLoc[0]*squareSize,squareSize,squareSize); } void turnLeft(){ if (antDirection &gt; 1){ antDirection--; } else{ antDirection = 4; } } void turnRight(){ if (antDirection &lt; 4){ antDirection++; } else { antDirection = 1; } } void moveForward(){ if (antDirection == 1){ antLoc[0]--; } if (antDirection == 2){ antLoc[1]++; } if (antDirection == 3){ antLoc[0]++; } if (antDirection == 4){ antLoc[1]--; } } void updateScene(){ moveForward(); if (state[antLoc[0]][antLoc[1]] == false){ state[antLoc[0]][antLoc[1]] = true; turnRight(); } else { state[antLoc[0]][antLoc[1]] = false; turnLeft(); } } void draw(){ background(bgCol); drawScene(); for(int i = 0; i &lt; 10; i++){ updateScene(); } } </code></pre>
 

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