Ebiten: Workable on the Go playground

[hajimehoshi]

https://twitter.com/bradfitz/status/1128069715455123457

Now Go Playground supports third party libraries, but of course Ebiten does not work :-)

The reason is that in the playground GOOS=nacl and Ebiten doesn't have driver implementations for this. For such environment, how about implementing a dummy drivers so that at least it can be 'compiled'?

This is not urgent but set the milestone 1.10.0 since Go Playground tries to get the latest stable version.

[hajimehoshi]

Now the playground supports go.mod, this issue is not urgent :-)

https://play.golang.org/p/KLZR7NlVZNX

[hajimehoshi]

Wow, the playground can show an image!

https://play.golang.org/p/EUijJdjjVqn

[hajimehoshi]

Animation

https://play.golang.org/p/YdB6oa55n-t

[hajimehoshi]

Unfortunately, as the playground capability is very limited, it'd not be feasible to make Ebiten work on the playground.