Raycasting - Java-Gaming.org

Hi. I decided to use the tutorials and source code from http://www.permadi.com/tutorial/raycast/index.html as a basis for a raycasting game/engine that I'd like to develop. It seems great so far, but there's something I'd like to change:

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  static final int ANGLE60 = PROJECTIONPLANEWIDTH;
  static final int ANGLE30 = (ANGLE60/2);
  static final int ANGLE15 = (ANGLE30/2);
  static final int ANGLE90 = (ANGLE30*3);
  static final int ANGLE180 = (ANGLE90*2);
  static final int ANGLE270 = (ANGLE90*3);
  static final int ANGLE360 = (ANGLE60*6);
  static final int ANGLE0 = 0;
  static final int ANGLE5 = (ANGLE30/6);
  static final int ANGLE10 = (ANGLE5*2);

  // trigonometric tables
  float fSinTable[];
  float fISinTable[];
  float fCosTable[];
  float fICosTable[];
  float fTanTable[];
  float fITanTable[];
  float fFishTable[];
  float fXStepTable[];
  float fYStepTable[];

and

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public void createTables()
  {
    int i;
    float radian;
    fSinTable = new float[ANGLE360+1];
    fISinTable = new float[ANGLE360+1];
    fCosTable = new float[ANGLE360+1];
    fICosTable = new float[ANGLE360+1];
    fTanTable = new float[ANGLE360+1];
    fITanTable = new float[ANGLE360+1];
    fFishTable = new float[ANGLE60+1];
    fXStepTable = new float[ANGLE360+1];
    fYStepTable = new float[ANGLE360+1];

    for (i=0; i<=ANGLE360;i++)
    {
      // get the radian value (the last addition is to avoid division by 0, try removing
          // that and you'll see a hole in the wall when a ray is at 0, 90, 180, or 270 degree)
      radian = arcToRad(i) + (float)(0.0001);
      fSinTable[i]=(float)Math.sin(radian);
      fISinTable[i]=(1.0F/(fSinTable[i]));
      fCosTable[i]=(float)Math.cos(radian);
      fICosTable[i]=(1.0F/(fCosTable[i]));
      fTanTable[i]=(float)Math.tan(radian);
      fITanTable[i]=(1.0F/fTanTable[i]);

        //  you can see that the distance between xi is the same
        //  if we know the angle
        //  _____|_/next xi______________
        //       |
        //  ____/|next xi_________   slope = tan = height / dist between xi's
        //     / |
        //  __/__|_________  dist between xi = height/tan where height=tile size
        // old xi|
        //                  distance between xi = x_step[view_angle];
        //
        //
        // facine left
      // facing left
      if (i>=ANGLE90 && i<ANGLE270)
      {
        fXStepTable[i] = (float)(TILE_SIZE/fTanTable[i]);
        if (fXStepTable[i]>0)
          fXStepTable[i]=-fXStepTable[i];
      }
      // facing right
      else
      {
        fXStepTable[i] = (float)(TILE_SIZE/fTanTable[i]);
        if (fXStepTable[i]<0)
          fXStepTable[i]=-fXStepTable[i];
      }

      // FACING DOWN
      if (i>=ANGLE0 && i<ANGLE180)
      {
        fYStepTable[i] = (float)(TILE_SIZE*fTanTable[i]);
        if (fYStepTable[i]<0)
          fYStepTable[i]=-fYStepTable[i];
      }
      // FACING UP
      else
      {
        fYStepTable[i] = (float)(TILE_SIZE*fTanTable[i]);
        if (fYStepTable[i]>0)
          fYStepTable[i]=-fYStepTable[i];
      }
    }

    for (i=-ANGLE30; i<=ANGLE30; i++)
    {
        radian = arcToRad(i);
        // we don't have negative angle, so make it start at 0
        // this will give range 0 to 320
        fFishTable[i+ANGLE30] = (float)(1.0F/Math.cos(radian));
    }

It seems that these tables generate trig function values that would only be of use to raycasting specifically with a specific width, height, and what not. I'd like to use something like this: http://code.google.com/p/libgdx/source/browse/trunk/gdx/src/com/badlogic/gdx/math/MathUtils.java because I feel it would unionize the trig functions more and not just serve the raycasting rendering process alone; I could use the trig functions for other things such as weapon bobbing movement.

Problem is, I'm completely lost and I don't have any idea how I can implement this and replace the old trig tables in the source code without it messing with the rendering process completely. Can anyone help me with this please?