Space Courier: Now We're Movin'

I should really get into the habit of writing these when I have easy access to the screenshots.

Small improvements to the game today:
http://bigdicegames.com/SpaceCourier/courier.html

• Planets - I put simple sprites (32px circles) in last night, including what may appear to a casual observer to be a small moon.
• Ship "animation" - when you hold the up arrow key, I increase a throttle variable. At certain points as that variable goes from 0 to 1, I switch from no rocket thrust to small thrust to full thrust. Likewise if you take your finger off the key.
• Ship movement - the ship was turning, and now it's moving. Well, the galaxy is moving. That is, I'm tracking "world" positions for the planets and the ship, and then I'm subtracting the ship position from the planet position to get the location of the various planets from where the ship is, and then I'm adding in some window coordinates to make everything centered in the viewport. Pretty straightforward stuff, and it'd be slightly less confusing if I had a better term for "world" coordinates when I also have "planet position", which may be in any coordinate frame.

To Do:

• Text rendering - gotta do this sooner or later, and almost all of the important gameplay features remaining require this. I kind of want to have labels on planets, but that might be distracting. Or maybe awesome. We'll see.
• Sounds - the optional OneGameAMonth theme is "sound". And I downloaded a few samples from freesound.org. In space, no one can hear you argue that rocket sound effects are out of place.
• Docking with planets
• Ship inventory
• Ship upgrades
• "Deck of Worlds" - right now, the planets have no identity - they have positions and sprites, but that's all. I'm thinking that I'll author a collection of defined planets (Aaalderoid is a peaceful, blue planet that produces 100 food, 10 fuel, and 10 ore a year). Initializing the galaxy map would consist of drawing cards from the deck, and then placing them somewhere in my navigation graph. This may lead to more custom planet art.
• Navigation graph - right now, the planets just cluster around the origin, more or less. I want to stretch them out so that no two planets are closer than roughly one screen height, and some are much further away. You know, for better exploring.