void hexagon(float sideLength, float xPos, float yPos){
  float c = sideLength;
  float a = cos(radians(30)) * c;
  float b = sin(radians(30)) * c;

  float[] A = {
    a+xPos, yPos  };
  float[] B = {
    2 * a+xPos, b+yPos  };
  float[] C = {
    2 * a+xPos, b + c +yPos };
  float[] D = {
    a+xPos, 2 * c +yPos  };
  float[] E = {
    a / c+xPos, b + c +yPos };
  float[] F = {
    a / c +xPos, b + yPos  };
  beginShape();
  vertex(A[0], A[1]);
  vertex(B[0], B[1]);
  vertex(C[0], C[1]);
  vertex(D[0], D[1]);
  vertex(E[0], E[1]);
  vertex(F[0], F[1]);
  vertex(A[0], A[1]);
  endShape();
}

void drawHexagon(float sideLength, int hNum, int vNum, int Color, int[][] Category){
  for(int i = 0; i < hNum; i++){
    for (int j = 0; j< vNum; j++){
      float alphaCate = map(Category[i][j],0,MaxTrans(Category),40,255);
      fill(colorIdx[Color][0],colorIdx[Color][1],colorIdx[Color][2],alphaCate);
      if(j%2==0){
        noStroke(); 
        hexagon(sideLength, i*sideLength*sqrt(3), int(j)/2*3*sideLength);
      }else{
        pushMatrix();
        translate(sideLength*sqrt(3)/2, 3*sideLength/2);
        hexagon(sideLength, i*sideLength*sqrt(3), int(j/2)*3*sideLength);
        popMatrix();
      }
    }
  }
}

void drawGrid(float sideLength, int hNum, int vNum){
  for(int i = 0; i < hNum; i++){
    for (int j = 0; j< vNum; j++){
      stroke(100);
      noFill();
      hexagon(sideLength, i*sideLength*sqrt(3), j*3*sideLength);
      pushMatrix();
      translate(sideLength*sqrt(3)/2, 3*sideLength/2);
      stroke(100);
      noFill();
      hexagon(sideLength, i*sideLength*sqrt(3), j*3*sideLength);
      popMatrix();
    }
  }
}

void drawGridSingle(float sideLength, int hNum, int vNum){
  for(int i = 0; i < hNum; i++){
    for (int j = 0; j< vNum; j++){
      //stroke(100);
      noFill();
      hexagon(sideLength, i*sideLength*sqrt(3), j*3*sideLength);
      pushMatrix();
      translate(sideLength*sqrt(3)/2, 3*sideLength/2);
      //stroke(100);
      noFill();
      hexagon(sideLength, i*sideLength*sqrt(3), j*3*sideLength);
      popMatrix();
    }
  }
}


int MaxTrans(int[][] Category){
  int MaxTrans=0;
  for(int i = 0; i < 10; i++){
    for(int j = 0; j < 30; j++){
      if(Category[i][j]>MaxTrans){
        MaxTrans = Category[i][j];
      }
    }
  }
  return(MaxTrans);
}