Generate Hexagon Points

Horizontal.js

var horizontalHexagonPoints = function (canvas, radius) {

      var size = {
        width: radius * 2,
        height: (radius / 2 * Math.sqrt(3)) * 2
      };

      var rows = Math.ceil(canvas.height / size.height) + 1;
      var columns = Math.ceil(canvas.width / (radius / 2 * 3)) + 1;

      var offset = {
        // (width - ((diameter * columns) - (((columns - 1) * radius) / 2))) / 2
        x: (canvas.width - ((size.width * columns) - (((columns - 1) * radius) / 2))) / 2,
        // (height - (innerDiameter * radius)) / 2
        y: (canvas.height - (size.height * rows)) / 2
      };

      var points = [];

      var y;

      for (var row = 0; row < rows; row++) {
        for (var col = 0; col < columns; col++) {
          y = col % 2 == 0 ? 0 : size.height / 2;
          points.push({
            x: offset.x + ((size.width - (radius / 2)) * col) + (size.width / 2),
            y: (offset.y + y) + (size.height * row) + (size.height / 2)
          })
        }
      }

      return points;
    };

Vertical.js

var verticalHexagonPoints = function (canvas, radius) {
      var size = {
        width: (radius / 2 * Math.sqrt(3)) * 2,
        height: radius * 2
      };

      var rows = Math.ceil(canvas.height / (radius / 2 * 3)) + 1;
      var columns = Math.ceil(canvas.width / size.width) + 1;

      var offset = {
        x: (canvas.width - (size.width * columns)) / 2,
        y: (canvas.height - ((size.height * rows) - (((rows - 1) * radius) / 2))) / 2
      };

      var points = [];  // these are the centroid points for the hexagon.

      var x;

      for (var row = 0; row < rows; row++) {
        for (var col = 0; col < columns; col++) {
          x = row % 2 == 0 ? 0 : size.width / 2;
          points.push({
            // (width - (innerDiameter * columns)) / 2
            x: (offset.x + x) + (size.width * col) + (size.width / 2),
            // (height - ((diameter * rows) - (((rows - 1) * radius) / 2))) / 2
            y: offset.y + ((size.height - (radius / 2)) * row) + (size.height / 2)
          })
        }
      }

      return points;
    };