Don't auto-split SVG floats before a -.

[xavidotron]

This is necessary to support numbers like 1e-6 with a - in the middle,
which happens in SVG produced by Inkscape.

Description

When SVGLoader loads an SVG file with a number like 1e-6 in a path, it parses that path incorrectly resulting in broken behavior. Because standard SVG-editing tools like Inkscape produce SVGs that contain numbers of this form, it can be easy to inadvertently produce SVGs that have this issue.

The attached broken.svg.zip contains a file that is handled correctly after this change and not before it.

[Mugen87]

Please change the examples/js version and generate the jsm version via node utils/modularize.js.

[yomboprime]

Related (same topic): #17306

[xavidotron]

Please change the examples/js version and generate the jsm version via node utils/modularize.js.

Done, thanks for the pointer.

[Mugen87]

This PR breaks the Zero Radius test file in webgl_loader_svg. Definitions like the following can't be processed anymore: "7,7,0,0,1-7-7".

1-7-7 becomes now 1-7-7 instead of 1, -7, -7.

[yomboprime]

I've come to a regexp that passes all tests. Keep in mind that I'm no expert, I'd like it to be verified:
/[\s,]+|(?=\s?[(^e+)(^e\-)])/
This one divides on + or - only when there is not an e just before them (that is what the ^ does)

For comparison, here is the previous regexp used in the repo:
/[\s,]+|(?=\s?[+\-])/

[Mugen87]

Alternatively to a different regex, I've implement parseFloats() base on this project: https://github.com/ppvg/svg-numbers

Here is the commit: Mugen87@a2b9ed8

svg-numbers seems to implement the number parsing in a very robust way.

[Mugen87]

One thing that confuses me: The loader currently uses parseFloatWithUnits() in parseFloats().

It seems svg-numbers does not honor units. Is that a problem?

[yomboprime]

One thing that confuses me: The loader currently uses parseFloatWithUnits() in parseFloats().

It seems svg-numbers does not honor units. Is that a problem?

I think you should implement parseFloat, which is used in parseFloatsWithUnit.

It is difficult to integrate units as it is right now...

[Mugen87]

svg-numbers is not intended to replace the JavaScript built-in parseFloat() function. The lib retrieves a string like "7,7,0,0,1-7-7" and outputs the split up numbers in an array.

[yomboprime]

Yes, I see. But the unit is just a string at the end, I think it should be not much work to add a new state to the parser.

[Mugen87]

@ppvg Is it possible that a list of coordinates in SVG documents such as the points attribute of a <polyline> element can have a unit? If so, is this handled in some way by svg-numbers?

[ppvg]

@Mugen87: oof, I wrote that 7 years ago. I'll have to refresh my memory. 😅
I'll try to find some time later this week.

[Mugen87]

@yomboprime Do you mind sharing a SVG file in this thread which can be used to evaluate the units issue?

[Mugen87]

According to my today's research SVG transform as well as shape definitions (like path, polygon or polyline) do not support units. Hence, it should be safe to not use parseFloatWithUnits() in parseFloats().

However, it would be good if this could be double-checked 😅 .

[yomboprime]

@yomboprime Do you mind sharing a SVG file in this thread which can be used to evaluate the units issue?

The test "Units" loads the file models/svg/tests/units.svg. It has three rectangles, with the same width expressed in different units. So at least the width of a rectangle can have units.

[yomboprime]

According to my today's research SVG transform as well as shape definitions (like path, polygon or polyline) do not support units. Hence, it should be safe to not use parseFloatWithUnits() in parseFloats().

However, it would be good if this could be double-checked sweat_smile .

I've made some reading of 1.1 and 2.0 SVG specs and it seems to be true.

[Mugen87]

Okay, let's give this PR a try. In this way, the more time we have to validate the change on dev.

[yomboprime]

Just as a final note, the OP's SVG test file broken.svg still renders incorrectly due to the other issues related to holes windings. If I delete the hole in the shape in Inkscape, it shows correctly.