I wrote an animated guide to do proper asset scaling and multi-resolution in Cocos2d-x. I am hoping it to be very clear on how to approach the problem, and how to solve it. After the post, a Cocos2d-x user reminded me this is one of the most discussed topics on the forum. So I decided I should post it here.
We, as 6x13 Games, released 4 mobile titles using the described method, and I know many others use similar approach. So, do not hesitate to use it in production. Good luck!
What is difference between ResolutionPolicy::SHOW_ALL and condition: “condition ? ResolutionPolicy::FIXED_WIDTH : ResolutionPolicy::FIXED_HEIGHT”.
For me it seem it will be exactly the same.
The difference will present itself if you check out the implementation of GLView::updateDesignResolutionSize().
The FIXED_HEIGHT and FIXED_WIDTH policies each recalculate design resolution accordingly. SHOW_ALL does not. Therefore, you will see black border due to clipping with SHOW_ALL, while you will see beautiful art in above version.
You are absolutely right that scaling is exactly the same, though the outcome will still be different.