Generating Expected Images for Tests

[ashes999]

Hi @jgranick and @ibilon ,

I would like your input on how we generate expected/good PNGs from SVGs for our tests. Currently, I have two SVGs (both circular logos) that I generated by rendering them in GIMP (which is free). This produced quite a big pixel difference (7% and 12%), mostly due to aliasing artifacts.

We need a "canonical" or "gold standard" renderer which we can use to generate these images. What comes to mind:

• Use an online "SVG to PNG converter" (so others can easily generate PNGs)
• Use GIMP, or some other free tool
• Run the tests and use the rendered output of the svg library itself to generate the "actual" images. (That means someone has to add a bunch of SVGs, and just verify that they look "good enough.")

How would you like to proceed?

P.S. if you have a sizable body of SVGs on-hand which already render correctly, I would like to add those to the tests too.

[ashes999]

It turns out GIMP does a reasonable job of this, and most of the circle artifacts disappear when you render larger images (256x256 instead of 64x64).

I'm okay with using GIMP for this for now. If you have feedback, please comment on this issue.