The LEARN
section of this website has a
number of sections that each deal with different aspects islamic
geometrical design.
INTRODUCTION:
What are the principles of islamic geometrical design?
GRIDS: The
hidden structure of Islamic geometric design, grids are made up of
polygons and allow for creativity and
innovation and make complex designs less complex.
Designs
based on the division of a circle into five equal parts has
characteristics that are different than all other kinds of geometrical
design. Find out why.
Learn
how to design one of the most common geometric designs in
Islamic art and architecture. All you need is a pencil, a
piece of
paper and a compass and a ruler.
LESSON 2:
Learn how to design another common geometric design
from
Islamic art and architecture.
POLYGONS:
The building blocks of geometric designs. Polygons
work together to make grids
MUQARNAS:
The
three- dimensional manifestation of two dimensional Islamic geometric
design. They are Islamic architecture's truly unique contribution to
world architecture.
Polygons
play a
fundamental role in Islamic geometrical design.
When combined with identical or other-shaped polygons they form grids.
These grids in turn form the structure behind geometrical
designs. Two examples of polygons are the snowflake on the
left
of this page and the tiles in the main picture. Both
of
these polygons are sixe sided and are called hexagons.
A six-sided
polygon is also known as a hexagon
A five-sided
polygon is known as a pentagon
A
seven-sided polygon is known as a heptagon
A
eight-sided polygon is known as a octagon
A
nine-sided polygon is known as a enneagon (or nonagon)
A
ten-sided polygon is known as a decagon
An eleven-sided
polygon is known as a hendecagon
A twelve-sided
polygon is known as a dodecagon
Traditional
craftsmen were able to draw polygons with just a compass and a ruler.
They did not need to calculate angles. Here are some examples
of how they did this:
How
to draw a square with just a compass and a ruler:
1.
Draw a horizontal line and place a circle on the line.
2.
Draw 2 arcs
of equal
size, the diameter is not important. Place the compasspoints
in
the intersections indicated with red circles.
3.
Draw a line that connects the intersecting arcs.
4.
Draw 4 circles of equal size. Place the compass points in
the
indicated intersections. The circles meet each other at the
intersection of the horizontal & vertical lines.
5. Draw
a square by connecting the 4 indicated intersections.
How
to draw a pentagon with just a compass and a ruler:
1. Draw
a circle and 2 lines as seen above in steps 1-3 of "how to draw
a square".
2. Draw
2 arcs of equal size, the diameter is not important.
Place the
compasspoints in the intersections indicated with red circles.
3. Draw
a line that connects the intersecting arcs.
4.
Place the compass- point in the indicated intersection &
draw an arc that intersects the vertical line & the circle
5.
Place the compass- point in the upper indicated
intersection & draw an arc that intersects the lower
indicated
intersection.
6. Draw
2 lines that connect the 3 indicatted intersections. These 2
lines from the 'roof' of the pentagon.
7. Place
the compass- point in the indicated intersections
& draw 2 arcs that intersect the top of the 'roof'.
8. Draw
3 lines that connect the four indicated intersections
9. The
pentagon is complete.
How
to draw a heptagon with just
a compass and a ruler
For many
centuries, mathematicians and
geometrists have
tried to find a method to divide a circle into seven equal parts. The
consensus
now is that it is impossible. However, we can see occurrences of
geometrical
designs in Islamic architecture that use 7-pointed stars, such as the
twinned
stars on the right in the minbar panel in the mosque of Qiqmas
al-Ishaqi in Cairo.
This means that there were very skilled Islamic craftsmen who were able
to
divide a circle into 7 parts with a compass and a
ruler. Mathematicians
cannot accept anything less than 100% accuracy but craftsmen can accept
a more
or less equal division of a circle into more or less equal
parts. The method shown here is devised by me and shows a
possible approach to
the
division of a circle into 7 equal parts. The margin of error is less
than 2%.
1. Draw
circle on a horizontal line and divide it into six
equal parts.
2. Draw
a pentagon as indicated.
3. Find
the halfway point on the circle between the indicated points of
the pentagon and hexagon.
4. Draw
a line that connects the point from the previous diagram with
the intersection of the circle with the horizontal line. Draw a circle
that touches this line as indicated.
5. Draw
a vertical line that touchces the circle as indicated.
6. Find
the halfway point on the circle between the two intersections
indicated by red circles.
7. Draw
two lines that connect the indicated intersections with the
halfway point from the previous diagram, these are the first two sides
of the heptagon.
8. Draw
3 arcs with the compasspoint on the indicated intersections.
The radius is the length of one of the sides of the heptagon.
9. Draw
the five remaining sides of the heptagon
10. A
heptagon drawn with a compass and a ruler.
The margin of error is less than 2%