## Friday, October 7, 2011

### DDTe3 Hour 17 - Hex Spin Puzzle

This is a continuation of my series on the creation of Dozen Days of Tiles episode 3 games on the Blazing Games site. While the other episodes in the Dozen Days series were about the creation of a game in under 24 hours, this episode is a challenge to see how many simple games can be created in under 24 hours. While this article covers the creation of the hex spin game, it is heavily dependent on the material covered in previous posts.

The next game to create this “day” is the hex-based variation of the spin puzzle. Because of the nature of the hex grid, the spin is a fairly natural operation. The spin, when looked at from a hex map perspective as figure 1 shows, is a very simple operation. Of course, using the grid coordinates that we are storing the hex in would make doing this procedure very tricky to code but by using the hex coordinate system that was discussed in an earlier article this can be a very easy piece of code to write.

 figure 1 - Hex Spin

Converting between the two coordinate systems is easy enough to do and could be done right in the spinning code, I have a third hex game in mind so it might be better off to put the conversion and translation of hex coordinates into it’s own class, which I called HexPoint. This class has methods for converting between the two coordinate systems as well as for translating (moving) the hex point along the x, y and z axis. The z axis is tied to the other two so manipulating the z axis actually adjusts both the x and y axis as the following code snippet shows.

{
}

The HexSpinPuzzle game is essentially the SpinPuzzle game but with a hex grid so the only code that really needs to be written to create this game is a spin methods. Because I am “borrowing” code from SpinPuzzle which itself was borrowed from TwistPuzzle, the method to perform the spin action is called performTwist. While the logic behind the spin is the same as with the two grid games, the implementation is a bit more complex due to the need to work with two different coordinate systems. While at first glance the code may seem complex, it is remarkably simple and took very little time to write. Essentially, all we are doing is defining a pair of hex coordinates which represent the tiles that are to be manipulated. We start by finding the coordinates of the starting point. I am using the y-1 hex coordinate, though any hex that circles the hex tile that was clicked on could have been chosen for the starting point. As with the regular twist and spin puzzles, we need to save this to a temporary variable as this tile is going to be replaced. The coordinate is saved in a second HexPoint and the original point is translated to the position of the tile that will be shifted into the original point. Becuse of the point chosen to start at, the order of the translations are x+1, y+1, z+1, x-1, and y-1. The final z-1 translation would take us back to the start so instead of doing that translation we instead use the temp value. After each translation, the tile at that location is copied to the previous position.

PuzzleGallery.HexSpinPuzzleGame.prototype.performTwist = function(p)
{
var hp1 = new PuzzleGallery.HexPoint();
var hp2 = new PuzzleGallery.HexPoint();

hp1.setPointFromGrid(p.x, p.y);
hp1.translateY(-1);
hp2.moveTo(hp1.x, hp1.y);
var temp = this.puzzle.getPuzzlePiece(hp1.getGridX(), hp1.getGridY());
hp1.translateX(1);
this.puzzle.setPuzzlePiece(
hp2.getGridX(), hp2.getGridY(),
this.puzzle.getPuzzlePiece(hp1.getGridX(), hp1.getGridY()));
hp2.moveTo(hp1.x, hp1.y);

hp1.translateY(1);
this.puzzle.setPuzzlePiece(
hp2.getGridX(), hp2.getGridY(),
this.puzzle.getPuzzlePiece(hp1.getGridX(), hp1.getGridY()));
hp2.moveTo(hp1.x, hp1.y);

hp1.translateZ(1);
this.puzzle.setPuzzlePiece(
hp2.getGridX(), hp2.getGridY(),
this.puzzle.getPuzzlePiece(hp1.getGridX(), hp1.getGridY()));
hp2.moveTo(hp1.x, hp1.y);

hp1.translateX(-1);
this.puzzle.setPuzzlePiece(
hp2.getGridX(), hp2.getGridY(),
this.puzzle.getPuzzlePiece(hp1.getGridX(), hp1.getGridY()));
hp2.moveTo(hp1.x, hp1.y);

hp1.translateY(-1);
this.puzzle.setPuzzlePiece(
hp2.getGridX(), hp2.getGridY(),
this.puzzle.getPuzzlePiece(hp1.getGridX(), hp1.getGridY()));
hp2.moveTo(hp1.x, hp1.y);

//    hp1.translateZ(-1);
this.puzzle.setPuzzlePiece(hp2.getGridX(), hp2.getGridY(), temp);

this.view.update();
}

With this done the game is ready. The next hex game should be fairly simple to write and will probably leave me with enough time to create an eighth game.