XG - stage 1 interactivity

I stretched the work time about 30 minutes extra this evening (to 3 hours) because I was in the middle of the last functionality I'd hoped to get done this evening, plus I figure it kind of balances losing 15 minutes to a stupid bug that resulted from mis-typing a ',' as a '.' :/

 Pretty pleased with progress so far: the little avatar circle can wander around (moves towards a touch or drag on the course area), has a reach, can place the ball, and can place, move, and recover charges. Plus, the timer on the ball control/display at the bottom of the screen starts burning when the ball is placed, giving a nice sense of urgency.

The plan for the next stage (which will be Thursday, as I'm busy tomorrow night) is implementing the UI for setting a timer on charges when they're placed. If that goes well I might get to implement the detonator as well.

I'm contemplating how to handle movement obstacles once I get to implementing them. Looking at making all world object either circles of polygons (i.e. sets of line segments). Then an avatar movement step can be modeled as a starting circle, an ending circle, and a (rotated) rectangle covering the traversed area. Checking intersections between those shapes and the world obstacles should then be pretty straightforward. Could do partial steps to approach the collision point once it's detected, but at least initially I'll simply stop movement if the next step has a collision (maneuvering the avatar is part of the game play, so I'm not worrying about any kind of clever pathing for it).

Time remaining: 10.5 hours
Forecast: somewhat intimidated, but looking forward to eating some of the pumpkin-cider bread that Amy (my wife) made this evening while I was coding