code: function drawUpperTriangle(d, loc) {
        if (d == "r") {
          var first = {x: 50, y: 0};
          var second = {x: 50, y: 50};
        } else {
          var first = {x: 50, y: 0};
          var second = {x: 0, y: 50};
        }
        context.beginPath();
        context.moveTo(loc.x, loc.y);
        context.lineTo(loc.x + first.x, loc.y + first.y);
        context.lineTo(loc.x + second.x, loc.y + second.y);
        context.lineTo(loc.x, loc.y);
        context.lineWidth = 1;
        context.strokeStyle = 'black';
        context.stroke();
        context.fillStyle = fill;
        context.fill();
        context.closePath();
      }
docs: draw upper triangle going certain direction at location