Take the mid points of a regular hexagon. Draw three axes as shown in the image(note the directions).
Move the mid-point pairs along these axes. You can as well move the three pair of points with different values. Any polygon you'll draw with this method will be seamlessly tileable. If you move all three starting points up to the hexagonal center, you'll get the Mitsubishi logo made up of three congruent rhombi which are made up of two equilateral triangles.