Refactoring a javascript array rotate function

Question

I wrote a rotate function, but I'm not satisfied with it:

var pixels=['011','110','000'];
var result=new Array();
result=['000','000','000'];
var r = {x:1,y:1}; //rotating point
var clock = true; //clock or counter-clock rotation


for ( y=0; y<(pixels.length); y++ ){
  for ( x=0; x<(pixels.length); x++ ){
    var newx=0,newy=0;
    if ( clock ){
      if ( x< r.x && y< r.y ) {newx=x+2;newy=y  ;}//top left
      if ( x==r.x && y< r.y ) {newx=x+1;newy=y+1;}//top
      if ( x> r.x && y< r.y ) {newx=x  ;newy=y+2;}//top right
      if ( x< r.x && y==r.y ) {newx=x+1;newy=y-1;}//left
      if ( x==r.x && y==r.y ) {newx=x  ;newy=y  ;}//center
      if ( x> r.x && y==r.y ) {newx=x-1;newy=y+1;}//right
      if ( x< r.x && y> r.y ) {newx=x  ;newy=y-2;}//bottom left
      if ( x==r.x && y> r.y ) {newx=x-1;newy=y-1;}//bottom
      if ( x> r.x && y> r.y ) {newx=x-2;newy=y  ;}//bottom right
    } else {
      if ( x< r.x && y< r.y ) {newx=x  ;newy=y+2;}//top left
      if ( x==r.x && y< r.y ) {newx=x-1;newy=y+1;}//top
      if ( x> r.x && y< r.y ) {newx=x-2;newy=y  ;}//top right
      if ( x< r.x && y==r.y ) {newx=x+1;newy=y+1;}//left
      if ( x==r.x && y==r.y ) {newx=x  ;newy=y  ;}//center
      if ( x> r.x && y==r.y ) {newx=x-1;newy=y-1;}//right
      if ( x< r.x && y> r.y ) {newx=x+2;newy=y  ;}//bottom left
      if ( x==r.x && y> r.y ) {newx=x+1;newy=y-1;}//bottom
      if ( x> r.x && y> r.y ) {newx=x  ;newy=y-2;}//bottom right
    }
    //inject(result,newx,newy,pixels[y][x])
  }
}

does someone now how to write a cleaner code for this rotate (clock and counter-clock) function ?

Is the `r` variable the same thing as `result`? If not, it's undefined. — James Kolpack, Apr 04 '10 at 17:29
thank you for the comment, I forgot to mention r was the pivot point (it's now corrected) — ideotop, Apr 04 '10 at 17:39

score 1 · Answer 1 · edited May 23 '17 at 12:19

1

You could try the suggestions in How to Rotate a 2D Array of Integers but then you would probably have to use an array of arrays, instead of an array of strings (which might make more sense anyway).

edited May 23 '17 at 12:19

Community

1
1

answered Apr 04 '10 at 17:29

Tyler

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Refactoring a javascript array rotate function

1 Answers1