Vector anti-aliasing issue

[tslocum]

Ebitengine Version

v2.8.0

Operating System

• Windows
• macOS
• Linux
• FreeBSD
• OpenBSD
• Android
• iOS
• Nintendo Switch
• PlayStation 5
• Xbox
• Web Browsers

Go Version (go version)

1.23.1

What steps will reproduce the problem?

Run Boxcars using the vector branch, which adds this commit using Ebitengine's vector package instead of draw2d. For comparison, the previous commit is this one. The only change between the two is which package is used to draw the vector graphics.

What is the expected result?

Anti-aliased triangles. This is the result when using draw2d with anti-aliasing enabled:

What happens instead?

Rough triangles. This is the result when using Ebitengine's vector package with anti-aliasing enabled:

Anything else you feel useful to add?

I tried different fill rules, but that did not seem to have any effect.

[hajimehoshi]

We might need a special shader to resolve this issue. As utilities, we might introduce some functions. See #3150

[hajimehoshi]

https://www.microsoft.com/en-us/research/wp-content/uploads/2005/01/p1000-loop.pdf (https://developer.nvidia.com/gpugems/gpugems3/part-iv-image-effects/chapter-25-rendering-vector-art-gpu) might be promising, but is this patented?: https://patents.google.com/patent/US20070097123

Example: https://www.shadertoy.com/view/flG3Rt