SpaceViewModel.of constructor

SpaceViewModel.of(DateTime time, SpaceConfig config, Size size)

Create a VM out of a time/config/screen size

Implementation

factory SpaceViewModel.of(DateTime time, SpaceConfig config, Size size) {
  /// Center of the Screen
  final centerOffset = Offset(size.width / 2, size.height / 2);

  /// Background size (at least hyp to fill screen as rotating)
  final backgroundSize =
      sqrt(size.width * size.width + size.height * size.height);

  /// The moon orbit (0-360 every 60 sec)
  final moonOrbit = (time.second * 1000 + time.millisecond) / 60000 * 2 * pi;

  /// The earth orbit (0-360 every 60 minutes)
  final earthOrbit =
      (time.minute * 60 * 1000 + time.second * 1000 + time.millisecond) /
          3600000 *
          2 *
          pi;

  /// The suns rotation (0-360 every 12 hours)
  final sunOrbit = (time.hour / 12.0) * 2 * pi + (1 / 12.0 * earthOrbit);

  /// The "Rotation" of the sun
  /// Is the base speed of the rotational perlin noise for the sun
  final sunRotation = sunOrbit * config.sunSpeed;

  /// The sun's diameter
  final sunSize = size.width * config.sunSize;

  /// The sun's base disc radius
  final sunBaseRadius = sunSize / 2 * config.sunBaseSize;

  /// The X and Y Offsets for the sun
  final sunOffsetX = cos(sunOrbit - config.angleOffset) *
      size.width *
      config.sunOrbitMultiplierX;
  final sunOffsetY = sin(sunOrbit - config.angleOffset) *
      size.height *
      config.sunOrbitMultiplierY;

  /// The X and Y offsets of the earth
  final earthOffsetX = cos(earthOrbit - config.angleOffset) *
      size.width *
      config.earthOrbitMultiplierX;
  final earthOffsetY = sin(earthOrbit - config.angleOffset) *
      size.height *
      config.earthOrbitMultiplierY;

  /// We use this in the Y offset of the Moon and the Scale
  final moonSin = sin(moonOrbit - config.angleOffset);

  //Moon orbits 1/4 a screen distance away from the earth as well
  final moonOffsetX = cos(moonOrbit - config.angleOffset) *
      size.width *
      config.moonOrbitMultiplierX;
  final moonOffsetY = moonSin * size.height * config.moonOrbitMultiplierY;

  /// The scale of the moon, adjusts with SIN of the rotation
  /// (bigger at bottom, smaller at top)
  final moonScale = moonSin * config.moonSizeVariation;
  final moonSize = size.width * (config.moonSize + moonScale);

  /// The rotating of the background image
  final backgroundRotation =
      earthOrbit * config.backgroundRotationSpeedMultiplier;

  /// The rotation of the moon
  final moonRotation = earthOrbit * config.moonRotationSpeed;

  /// The size of the earth
  final earthSize = size.width * config.earthSize;

  /// The Screen Offsets of the Sun, Earth and Moon
  /// Screen offset of the moon
  final moonOffset = Offset(size.width / 2 + earthOffsetX + moonOffsetX,
      size.height / 2 + earthOffsetY + moonOffsetY);

  final earthOffset =
      Offset(size.width / 2 + earthOffsetX, size.height / 2 + earthOffsetY);

  final sunOffset =
      Offset(size.width / 2 + sunOffsetX, size.height / 2 + sunOffsetY);

  /// Create the view model we draw with
  return SpaceViewModel(
      backgroundRotation: backgroundRotation,
      earthOffset: earthOffset,
      earthSize: earthSize,
      earthRotation: earthOrbit * config.earthRotationSpeed,
      moonSize: moonSize,
      sunBaseRadius: sunBaseRadius,
      sunSize: sunSize,
      sunRotation: sunRotation,
      sunOffset: sunOffset,
      moonOffset: moonOffset,
      moonRotation: moonRotation,
      centerOffset: centerOffset,
      backgroundSize: backgroundSize);
}