sarabander / sicp-pdf

SICP PDF with Texinfo and LaTeX source
http://sicpebook.wordpress.com/
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The wave painter is inconsistent with the paper version, and exercise 2.49d is thus unsolvable. #34

Open ghost opened 4 years ago

ghost commented 4 years ago

In the exercise 2.49d, the student is asked to replicate the "wave" painter using a "draw-line" primitive.

Though it IS possible using the paper version of the book (because the wave painter is built up from straight segments), it is not possible in the pdf version, because the wave painter is unrelated.

xdavidliu commented 4 years ago

I don't understand the second paragraph; what difference in the pdf version makes it so that the wave painter is unrelated?

ghost commented 4 years ago

Andres' version:

image

The original version:

image

The original version can be build from straight lines. The new version needs curves.