Optimize drawing plan for a polargraph
Optimize the included drawing plan map.txt:
$ time ./process.py map.txt > map_optimized.txt
Total Glyphs: 8074
Initial penup distance: 4107485
Initial total distance: 4742961
Deduped penup distance: 3494625
Deduped total distance: 4040278
Sorted penup distance: 5319295
Sorted total distance: 5864948
Greedy penup (i=0) 124384
Greedy total (i=0) 670037
real 1m0.164s
user 1m0.088s
sys 0m0.024s
Now map_optimized.txt includes a reordered drawing plan with duplicate glyphs removed and with an improved ordering.
The optimization algorithm is basically this:
- Remove path sections which are exact duplicates of earlier sections
- Reorder paths:
- Pick the first path as the first path in the input file
- Find the path that starts nearest the previous one's endpoint, or the one which, if reversed, would start nearest the previous one's endpoint
- Repeat until we have processed all paths
For the drawing plan map.txt included, this results in a 7.1x improvement in total pen travel distance (see code for definition of distance). Actual results will vary due to a variety of factors. Please report real-life results so we can include them here!