As with last week, the assignment is to bring together the lsystem and
turtle interpreter classes to make a scene that consists of fractal
shapes and trees. Your top-level program will import both the lsystem
and interpreter modules. Unlike last week, however, your scene.py may
not import the turtle module or make any calls to turtle commands
directly. If you want to draw something, you have to pass a string to
the interpreter drawString method. There will be no exceptions to that
rule. (Note that you may attach arbitrary meaning to any character not
used by an L-system grammar.)
We want to be able to change the color of elements in an Lsystem
without affecting the color of other elements. We would also like to
avoid setting colors, widths, or other turtle drawing
features by adding new parameters to drawString. Instead, modify
your drawString method so that it handles five additional
characters in the strings.
'<' - the left angle bracket should push the current turtle color
onto a color stack. You'll need to create a separate colorstack
variable similar to the one used for position and heading. You can
use the function turtle.color() to get the turtle's current color.
Note that this function returns a tuple of colors. You should append
just the first element of the tuple onto the color stack.
colorstack.append( turtle.color() )
'>' - the right angle bracket should pop the current turtle color
off the color stack and set the turtle's color to that value.
'g' - set the turtle's color to green (e.g. (0.15, 0.5, 0.2) ).
'y' - set the turtle's color to light yellow ( e.g. (0.8, 0.8, 0.3) ).
'r' - set the turtle's color to red ( e.g. (0.7, 0.2, 0.3) ).
Be sure to use the turtle.color() and turtle.width() methods
properly. They are turtle functions, and the new color or new
width needs to be an argument to the function.
Once you have made the modifications to drawString, try
running systemFL using the
classtest.py test function from the lab.
You can also use the test function single.py
to draw just a single tree.
Create a file arrangement.py. Have the file import lsystem and
turtle_interpreter (the new versions). Write a function that makes
an arrangement of trees or flowers. The scene should include some
multi-rule L-systems with leaves or other ornaments that make use
of the color store/restore. You can use the symbol L to
indicate a leaf, which could be drawn as a semicircle or a circle
or a line. The following are variations with leaves and flowers,
all defined by strings (no special characters
except L). Try to include L-system trees with different
numbers of iterations. (Note that at least two of the L-systems
you use must have at least 2 rules.)
Please indicate either in your write-up or in your code which
L-systems you use. If you happen to use command line arguments
to specify filenames and don't tell us which systems you used,
then we can't run your code to reproduce your image. So either
hard-code which L-systems you use or indicate which ones you
used to make the pictures in your report.
Make two new L-systems. They can be variations on one of the ones
provided, an variation on an L-system from the ABOP book, or one
you create on your own. The L-systems of interest are given in the
chapter 1, pages 10, 11, and 25.
If you use a variation, include both the original and your variant in
your writeup. (The difference does not have to be large.)
In the file growth.py, create a scene function that makes an
image using your L-systems after 2, 3, and 4 iterations. Note,
if using a different pattern of iterations is more interesting
(e.g. 4, 5, 6 or 2, 4, 6) you are free to use a different set of
three iteration values. Indicate what you used in your writeup.
This is required image 2.
Please indicate either in your write-up or in your code which
L-systems you used (and include the txt files for your new L-systems
with your code when you turn it in!).
Have each tree exhibit some variation by modifying aspects of how it
Add leaves, berries, or color to your trees by adding symbols to the
rules and cases to your turtle interpreter. For each new symbol, you will
need another elif case in your drawString method.
In the Lsystem class create a method def __str__(self) that
returns a nicely formatted string that might look like the following
rule X -> F-[[X]+X]+F[+FX]-X
rule F -> FF
The __str__ method gets called automatically when an object is
printed out. It's also called to implement casting an object to a
string using str(thing). Note that your __str__ method should
not print anything out. It should build a string from the
information in your L-system and return the string. Remember
that '\n' is how you create a newline character.
In the test main function the line:
should print out your nicely formatted string instead of the generic
class instance string when you run your lsystem.py file.
See if you can draw the base string and rule below the image of a
tree from that L-system.
Get fancy with required images 2 or 3. "Fancy" means using
programming structures (functions, loops, conditionals, lists, or
math) to make a more interesting scene. Describe what you did in
Make more L-systems.
Demonstrate that you can create other kinds of shapes (like squares,
triangles, etc) by passing strings to the turtle interpreter's drawString
Make a new wiki page for your assignment. Put the label cs151s18project8
on the page. Each of you needs to make your own writeup.
In addition to making the wiki page writeup, put the python files you
wrote on the Courses server in your private directory in a folder
In general, your writeup should follow the outline below.
Title includes your name and clearly describes the project.
Section headings are used to delineate distinct sections of the report.
Abstract identifies key lecture concepts (e.g. code structres, data types, and libraries) relevant to the project.
Abstract explains why key lecture concepts are important to achieving project goals.
Abstract identifies program output(s), giving context to the project tasks.
Solutions to tasks are described, focusing on how you used key lecture concepts to solve each task.
Required images/outputs are present and clearly labeled.
Reflection at the end of the report addresses how the lecture concepts mentioned in the abstract made this project possible. If you can think of a more elegant way to achieve the same results, please share!
Sources, imported libraries, and collaborators are cited, or a note is included indicating that none were referenced.
Double-check this week's label. Make sure it is there.