Navigation part of the RawTurtle. Implements methods for turtle movement.
| 1509 | onkeyrelease = onkey |
| 1510 | |
| 1511 | class TNavigator(object): |
| 1512 | """Navigation part of the RawTurtle. |
| 1513 | Implements methods for turtle movement. |
| 1514 | """ |
| 1515 | START_ORIENTATION = { |
| 1516 | "standard": Vec2D(1.0, 0.0), |
| 1517 | "world" : Vec2D(1.0, 0.0), |
| 1518 | "logo" : Vec2D(0.0, 1.0) } |
| 1519 | DEFAULT_MODE = "standard" |
| 1520 | DEFAULT_ANGLEOFFSET = 0 |
| 1521 | DEFAULT_ANGLEORIENT = 1 |
| 1522 | |
| 1523 | def __init__(self, mode=DEFAULT_MODE): |
| 1524 | self._angleOffset = self.DEFAULT_ANGLEOFFSET |
| 1525 | self._angleOrient = self.DEFAULT_ANGLEORIENT |
| 1526 | self._mode = mode |
| 1527 | self.undobuffer = None |
| 1528 | self.degrees() |
| 1529 | self._mode = None |
| 1530 | self._setmode(mode) |
| 1531 | TNavigator.reset(self) |
| 1532 | |
| 1533 | def reset(self): |
| 1534 | """reset turtle to its initial values |
| 1535 | |
| 1536 | Will be overwritten by parent class |
| 1537 | """ |
| 1538 | self._position = Vec2D(0.0, 0.0) |
| 1539 | self._orient = TNavigator.START_ORIENTATION[self._mode] |
| 1540 | |
| 1541 | def _setmode(self, mode=None): |
| 1542 | """Set turtle-mode to 'standard', 'world' or 'logo'. |
| 1543 | """ |
| 1544 | if mode is None: |
| 1545 | return self._mode |
| 1546 | if mode not in ["standard", "logo", "world"]: |
| 1547 | return |
| 1548 | self._mode = mode |
| 1549 | if mode in ["standard", "world"]: |
| 1550 | self._angleOffset = 0 |
| 1551 | self._angleOrient = 1 |
| 1552 | else: # mode == "logo": |
| 1553 | self._angleOffset = self._fullcircle/4. |
| 1554 | self._angleOrient = -1 |
| 1555 | |
| 1556 | def _setDegreesPerAU(self, fullcircle): |
| 1557 | """Helper function for degrees() and radians()""" |
| 1558 | self._fullcircle = fullcircle |
| 1559 | self._degreesPerAU = 360/fullcircle |
| 1560 | if self._mode == "standard": |
| 1561 | self._angleOffset = 0 |
| 1562 | else: |
| 1563 | self._angleOffset = fullcircle/4. |
| 1564 | |
| 1565 | def degrees(self, fullcircle=360.0): |
| 1566 | """ Set angle measurement units to degrees. |
| 1567 | |
| 1568 | Optional argument: |