Add support for layer blend mode "bm" for NORMAL, SCREEN, OVERLAY, DARKEN, LIGHTEN, and ADD

[kudanai]

Adds support for "bm" (BlendMode) on layers. Possibly addresses #1055 Might need a little bit of a refactor. Relies on Paint.setBlendMode() available in android Q and up.

Sample before & after

[github-actions[bot]]

Snapshot Tests API 23: Report Diff API 31: Report Diff

[kudanai]

Thank you for the feedback.

I understand what you mean by the version check. I could suggest rolling back a little and only supporting the blend modes that have lower minsdk requirements, and continue working on it from there. Does that seem like a more prudent approach?

Also I wasn't entirely sure about the structure of that enum, it feels overly verbose to me. However since bm can also appear for shapes, figured it might be useful to leave the enum itself in place.

Done! Meanwhile, I will collect some sample lotties with specific blend modes and drop them in the directory.

[github-actions[bot]]

Snapshot Tests API 23: Report Diff API 31: Report Diff

[kudanai]

Pushing new changes:

• Separate out the backwards compatible blend modes and ones that are only Q+
  • They've been moved out into a separate (unused for now) method
  • we'll be enabling 6/18 blend modes: NORMAL, SCREEN, OVERLAY, DARKEN, LIGHTEN, and ADD
• Removed API version guard while actually applying the layer blend mode

[github-actions[bot]]

Snapshot Tests API 23: Report Diff API 31: Report Diff

[kudanai]

The supported modes look consistent to me on 23 and 31 now

[github-actions[bot]]

Snapshot Tests API 23: Report Diff API 31: Report Diff