http://www.smashingmagazine.com/2015/09/principles-of-html5-game-design/
And a bonus (linked from that article): an MDN article on 2d collision detection:
https://developer.mozilla.org/en-US/docs/Games/Techniques/2D_collision_detection
http://www.smashingmagazine.com/2015/09/principles-of-html5-game-design/
And a bonus (linked from that article): an MDN article on 2d collision detection:
https://developer.mozilla.org/en-US/docs/Games/Techniques/2D_collision_detection