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Add documentation for SequenceEffect

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This commit is contained in:
Lukas Klingsbo
2020-05-25 20:14:05 +02:00
parent 932e974028
commit ba5ab70cf0
3 changed files with 36 additions and 15 deletions
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18
doc/effects.md
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@ -66,6 +66,24 @@ square.addEffect(RotateEffect(
));
```
## SequenceEffect
This effect is a combination of other effects. You provide it with a list of your predefined effects, that are not added to a component.
Note that no effects added to the sequence can have their `isInfinite` property set to `true`, because then naturally the sequence will get stuck once it gets to that effect.
You can make the sequence go in a loop by setting both `isInfinite: true` and `isAlternating: true`.
Usage example:
```dart
final sequence = SequenceEffect(
effects: [move1, scale, move2, rotate],
isInfinite: true,
isAlternating: true);
myComponent.addEffect(sequence);
```
An example of how to use the SequenceEffect can be found [here](/doc/examples/effects/sequence_effect).
# Examples
Full examples can be found [here](/doc/examples/effects/simple) and [here](/doc/examples/effects/infinite_effects).

3
doc/examples/effects/sequence_effect/lib/main.dart
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@ -67,7 +67,8 @@ class MyGame extends BaseGame with TapDetector {
final sequence = SequenceEffect(
effects: [move1, scale, move2, rotate],
isInfinite: true, isAlternating: true);
isInfinite: true,
isAlternating: true);
greenSquare.addEffect(sequence);
}
}

30
lib/effects/sequence_effect.dart
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@ -10,7 +10,7 @@ import '../position.dart';
class SequenceEffect extends PositionComponentEffect {
final List<PositionComponentEffect> effects;
int _currentIndex = 0;
PositionComponentEffect _currentEffect;
PositionComponentEffect currentEffect;
bool _currentWasAlternating;
double _driftModifier = 0.0;
@ -38,12 +38,14 @@ class SequenceEffect extends PositionComponentEffect {
currentSize = Position.fromSize(effect.size);
}
});
travelTime = effects.fold(0, (time, effect) => time + effect.travelTime *
(effect.isAlternating ? 2 : 1));
travelTime = effects.fold(
0,
(time, effect) =>
time + effect.travelTime * (effect.isAlternating ? 2 : 1));
component.setBySize(originalSize);
component.setByPosition(originalPosition);
_currentEffect = effects.first;
_currentWasAlternating = _currentEffect.isAlternating;
currentEffect = effects.first;
_currentWasAlternating = currentEffect.isAlternating;
}
@override
@ -53,11 +55,11 @@ class SequenceEffect extends PositionComponentEffect {
}
super.update(dt);
_currentEffect.update(dt + _driftModifier);
currentEffect.update(dt + _driftModifier);
_driftModifier = 0.0;
if (_currentEffect.hasFinished()) {
_driftModifier = _currentEffect.driftTime;
_currentEffect.isAlternating = _currentWasAlternating;
if (currentEffect.hasFinished()) {
_driftModifier = currentEffect.driftTime;
currentEffect.isAlternating = _currentWasAlternating;
_currentIndex++;
final iterationSize = isAlternating ? effects.length * 2 : effects.length;
if (_currentIndex != 0 && _currentIndex % iterationSize == 0) {
@ -66,14 +68,14 @@ class SequenceEffect extends PositionComponentEffect {
}
final orderedEffects =
curveDirection.isNegative ? effects.reversed.toList() : effects;
_currentEffect = orderedEffects[_currentIndex % effects.length];
_currentWasAlternating = _currentEffect.isAlternating;
currentEffect = orderedEffects[_currentIndex % effects.length];
_currentWasAlternating = currentEffect.isAlternating;
if (isAlternating &&
!_currentEffect.isAlternating &&
!currentEffect.isAlternating &&
curveDirection.isNegative) {
// Make the effect go in reverse
_currentEffect.isAlternating = true;
_currentEffect.percentage = 1.0;
currentEffect.isAlternating = true;
currentEffect.percentage = 1.0;
}
}
}