Shape command not handled: e-4

Processing Coding Questions
1

Hey all,

Today I had a sketch like this:

PShape s;

void setup() {
  size(400, 300);
  s = loadShape("shape.svg");
}

void draw() {
  background(255);
 shape(s);
}

And the Processing IDE tells me

shape command not handled: e-4

I figured out what this means! It means that there is something in the XML of the SVG that Processing doesn’t like.

And what is that? It is e-4. It occurred in a string like this

-0.35022 -2.1e-4,-0.71185 0.14827

This may look like some SVG command or a problem with commas or white space, but is much simpler than that. It is a case of Scientific_notation. And Processing doesn’t like it.

This -2.1e-4 should be this -0.00021. Do that and the error is gone.

How to convert scientific notation in Processing-friendly notation? Python and regex to the rescue!

import re

def scientific_to_float(match):
    return str(float(match.group()))
pattern = r'\b\d+(\.\d+)?e-4\b'
with open('input.svg', 'r') as file:
    content = file.read()
updated_content = re.sub(pattern, scientific_to_float, content)
with open('output.svg', 'w') as file:
    file.write(updated_content)

Hope this helps!

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