mirror of
https://github.com/flame-engine/flame.git
synced 2025-11-16 12:48:19 +08:00
0c3d8f1bf1
* Removing Util.dart and moving its remaining parts to better places * Fixing lint * Doc fixes * Doc fixes * PR suggestions
151 lines
4.4 KiB
Markdown
151 lines
4.4 KiB
Markdown
# Util
|
|
|
|
On this page you can find documentation for some utility classes and methods.
|
|
|
|
## Device Class
|
|
|
|
This class, accessible via `Flame.device`, has some functions that can be used to control the state of the device, like changing the screen orientation for example.
|
|
|
|
### `Flame.device.fullScreen()`
|
|
|
|
When called, this disables all `SystemUiOverlay` making the app full screen.
|
|
When called in the main method, makes your app full screen (no top nor bottom bars)
|
|
|
|
**Note:** Has no effect when called on the web.
|
|
|
|
### `Flame.device.setLandscape()`
|
|
|
|
This method sets the orientation of the whole application (effectively, also the game) to landscape and depending on operating system and device setting, should allow both left and right landscape orientations. To set the app orientation to landscape on a specific direction, use either `Flame.device.setLandscapeLeftOnly` or `Flame.device.setLandscapeRightOnly`.
|
|
|
|
**Note:** Has no effect when called on the web.
|
|
|
|
### `Flame.device.setPortrait()`
|
|
|
|
This method sets the orientation of the whole application (effectively, also the game) to portrait and depending on operating system and device setting, should allow both up and down landscape orientations. To set the app orientation to portrait on a specific direction, use either `Flame.device.setPortraitUpOnly` or `Flame.device.setPortraitDownOnly`.
|
|
|
|
**Note:** Has no effect when called on the web.
|
|
|
|
### `Flame.device.setOrientation()` and `Flame.device.setOrientations()`
|
|
|
|
If a finer control of the allowed orientations is required (without having to deal with `SystemChrome` directly), `setOrientation` (accepts a single `DeviceOrientation` as a parameter) and `setOrientations` (accepts a `List<DeviceOrientation>` for possible orientations) can be used.
|
|
|
|
**Note:** Has no effect when called on the web.
|
|
|
|
## Timer
|
|
|
|
Flame provides a simple utility class to help you handle countdowns and event like events.
|
|
|
|
__Countdown example:__
|
|
|
|
```dart
|
|
import 'dart:ui';
|
|
|
|
import 'package:flame/game.dart';
|
|
import 'package:flame/text_config.dart';
|
|
import 'package:flame/timer.dart';
|
|
import 'package:flame/vector2.dart';
|
|
|
|
class MyGame extends Game {
|
|
final TextConfig textConfig = TextConfig(color: const Color(0xFFFFFFFF));
|
|
final countdown = Timer(2);
|
|
|
|
MyGame() {
|
|
countdown.start();
|
|
}
|
|
|
|
@override
|
|
void update(double dt) {
|
|
countdown.update(dt);
|
|
if (countdown.finished) {
|
|
// Prefer the timer callback, but this is better in some cases
|
|
}
|
|
}
|
|
|
|
@override
|
|
void render(Canvas canvas) {
|
|
textConfig.render(
|
|
canvas,
|
|
"Countdown: ${countdown.current.toString()}",
|
|
Vector2(10, 100),
|
|
);
|
|
}
|
|
}
|
|
|
|
```
|
|
|
|
__Interval example:__
|
|
|
|
```dart
|
|
import 'dart:ui';
|
|
|
|
import 'package:flame/game.dart';
|
|
import 'package:flame/text_config.dart';
|
|
import 'package:flame/timer.dart';
|
|
import 'package:flame/vector2.dart';
|
|
|
|
class MyGame extends Game {
|
|
final TextConfig textConfig = TextConfig(color: const Color(0xFFFFFFFF));
|
|
Timer interval;
|
|
|
|
int elapsedSecs = 0;
|
|
|
|
MyGame() {
|
|
interval = Timer(
|
|
1,
|
|
callback: () => elapsedSecs += 1,
|
|
repeat: true,
|
|
);
|
|
interval.start();
|
|
}
|
|
|
|
@override
|
|
void update(double dt) {
|
|
interval.update(dt);
|
|
}
|
|
|
|
@override
|
|
void render(Canvas canvas) {
|
|
textConfig.render(canvas, "Elapsed time: $elapsedSecs", Vector2(10, 150));
|
|
}
|
|
}
|
|
|
|
```
|
|
|
|
Timer instances can also be used inside a `BaseGame` game by using the `TimerComponent` class.
|
|
|
|
__Timer Component__
|
|
|
|
```dart
|
|
import 'package:flame/timer.dart';
|
|
import 'package:flame/components/timer_component.dart';
|
|
import 'package:flame/game.dart';
|
|
|
|
class MyBaseGame extends BaseGame {
|
|
MyBaseGame() {
|
|
add(
|
|
TimerComponent(
|
|
Timer(
|
|
10,
|
|
callback: () => print("10 seconds elapsed"),
|
|
repeat: true,
|
|
)
|
|
..start()
|
|
)
|
|
);
|
|
}
|
|
}
|
|
```
|
|
|
|
## Extensions
|
|
|
|
Flame bundles a collection of utility extensions, these extensions are meant to help the developer with shortcuts and converion methods, here you can find the summary of those extensions
|
|
|
|
They can all be imported on `package:flame/extensions/...`
|
|
|
|
### Canvas
|
|
|
|
Methods:
|
|
- `scaleVector`: Just like `canvas scale` method, but takes a `Vector2` as an argument.
|
|
- `translateVector`: Just like `canvas translate` method, but takes a `Vector2` as an argument.
|
|
- `renderAt` and `renderRotated`: if you are directly rendering to the `Canvas`, you can use these functions to easily manipulate coordinates to render things on the correct places. They change the `Canvas` transformation matrix but reset afterwards.
|