SimpleHexagonGrid.pde

// see https://www.redblobgames.com/grids/hexagons/

float size = 1000/24;
float w = size*2;
float h = sqrt(3)*size;
float xStep = w*(3/4f);
float yStep = h;
int xCount;
int yCount;

void setup() {
  size(1000, 1000);
  xCount = floor(width/xStep+2);
  yCount = floor(height/yStep+2);
}

void draw() {
  background(0);
  noFill();
  stroke(255);
  strokeWeight(4);
  drawHexagonGrid();
}


void drawHexagonGrid() {
  for (float xi = -xCount/2; xi <= xCount/2; xi++) {
    for (float yi = -yCount/2; yi <= yCount/2; yi ++) {
      float x = width/2 + xi*xStep;
      float y = height/2 + yi*yStep-yStep/2f;
      if (xi % 2 ==0) {
        y += yStep/2f;
      }
      pushMatrix();
      translate(x, y);
      drawHexagon();
      popMatrix();
    }
  }
}


void drawHexagon() {
  beginShape();
  for (int i = 0; i < 6; i++) {
    float theta = map(i, 0, 6, 0, TAU);
    vertex(size*cos(theta), size*sin(theta));
  }
  endShape(CLOSE);
}