grafx - Extensible Java Graphics Package Code

Quickie fix for NaN handling in line clipping strategy. This fix isn't
satisfactory without more comprehensive tests for points, lines, and polygons.
Committing this and will then immediately back out, I may resume on proper NaN
handling at some later point in time.

Upping the millisFailBlkMvTime to 2/3 of regular move time; was at 1/2. This
would mean that the movement reaches an apex of 2/(3*2) which is 1/3. Before
it reached an apex of 0.25.

Trying to use sqrt() and sin() to make the inversion curve better. I may have
discovered a rendering bug, it causes some sort of exception. Saving demo as
'data/drawing-bug.blo' which exposes the drawing bug.

Starting to improve the inversion animation. Still missing the trig funcs.
BTW SimpleGameLogic wasn't broken after all. My prev comment in SVN log was
incorrect.

We have a very rudimentary block inversion animation. The translation
component is being computed incorrectly in SimpleGameLogic.

In LocalBlockoutBoard, I think this logic will handle the animation end state
for inversion; any sort of smooth animation is still lacking. This should now
theoretically work in game, but I still have not tested this feature.

Flipping order of a 'if/else' in LocalBlockoutBoard which makes the logic flow
more easily.

Laying the groundwork for block inversion support, with nice animations of
that. To do this, m_currRot had to be tweaked to declare it as
AttemptedBlockMovementEvent instead of the prior AttemptedBlockRotationEvent,
which is a more general case, and so inversions can be stuffed into that
parameter as well. We're sort of going to treat inversions as rotations.

Defining m_currRotSpiegelUnits.

Introducing m_blockRotationPreAnim which paves the way for inversion animation.
Also introduced isEvtType() which makes the bitwise '&' operations clearer.