Page 4: Self-Check: Tree Variations

Unit 7, Lab 1, Page 4

On this page, you will determine what changes to the tree code would produce specific changes to the resulting image.

All of the images in the Self-Check Questions below are based on variations of this recursive tree procedure.
tree level: (level #) size: (size #){ if (level=1) { move (size) steps move(-1*size) steps} else{ move (size) steps turn counterclockwise (15) degrees tree level: (level-1) size: (size*0.75) turn clockwise(15) degrees turn clockwise(15) degrees tree level: (level-1) size: (size*0.75) turn counterclockwise (15) move(-1*size) steps } } output of 'tree level: (5) size: (100)' Upwards facing tree with trunk and four levels of branches

What was changed in the code?
The turn amount between branches
Correct!

The scaling factor (how much the length decreases each time)
Notice how the branches are now tilted differently from those in the original image.

Additional recursive calls to the function and additional turn blocks
There are still the same number of branches at each stage.

What was changed in the code?
The turn amount between branches
We did change angles here, but those are not the only changes we made. Where did those extra branches come from?

The scaling factor (how much the length decreases each time)
The branch lengths look pretty similar to the original.

Additional recursive calls to the function and additional turn blocks
Correct! There are now five recursive calls (branches).

What was changed in the code?
The turn amount between branches
The angles look pretty similar to the original.

The scaling factor (how much the length decreases each time)
Right! At each stage, the branches are getting longer.

Additional recursive calls to the function and additional turn blocks
There are the same number of branches, and the angles haven’t changed.

What was changed in the code?
The turn amount between branches
The angles look pretty similar to the original.

The scaling factor (how much the length decreases each time)
Right! At each stage, the branches are staying the same length, rather than shrinking.

Additional recursive calls to the function and additional turn blocks
There are the same number of branches, and the angles haven’t changed.

What was changed in the code?
The turn amount between branches
Correct! The turning angles are 90 degrees in this case.

The scaling factor (how much the length decreases each time)
It’s a bit hard to tell, but the scale factor is the same as the original.

Additional recursive calls to the function and additional turn blocks
There are the same number of branches in this tree.