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Move files to src and comply with the dart package layout convention (#621)

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* 👌 Use `Offset` type directly in `JoystickAction.update` calculations (#631)

* Move files to src and comply with the dart package layout convention

* Fixing widgets example

Co-authored-by: Serge Matveenko <lig@countzero.co>
Co-authored-by: Erick Zanardo <erickzanardoo@gmail.com>
This commit is contained in:
Renan
2021-01-20 09:05:43 -03:00
committed by GitHub
parent a8ef5cadea
commit ccee9a466b
146 changed files with 1232 additions and 1275 deletions
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106
lib/spritesheet.dart
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@ -1,105 +1 @@
import 'dart:ui';
import 'package:meta/meta.dart';
import 'extensions/vector2.dart';
import 'sprite.dart';
import 'sprite_animation.dart';
/// Utility class to help extract animations and sprites from a sprite sheet image.
///
/// A sprite sheet is a single image in which several regions can be defined as individual sprites.
/// For the purposes of this class, all of these regions must be identically sized rectangles.
/// You can use the [Sprite] class directly if you want to have varying shapes.
///
/// Each sprite in this sheet can be identified either by it's (row, col) pair or
/// by it's "id", which is basically it's sequenced index if the image is put in a
/// single line. The sprites can be used to compose an animation easily if they
/// all the frames happen to be sequentially on the same row.
/// Sprites are lazily generated but cached.
class SpriteSheet {
/// The src image from which each sprite will be generated.
final Image image;
/// The size of each rectangle within the image that define each sprite.
///
/// For example, if this sprite sheet is a tile map, this would be the tile size.
/// If it's an animation sheet, this would be the frame size.
final Vector2 srcSize;
final Map<int, Sprite> _spriteCache = {};
/// Creates a sprite sheet given the image and the tile size.
SpriteSheet({
@required this.image,
@required this.srcSize,
});
SpriteSheet.fromColumnsAndRows({
@required this.image,
@required int columns,
@required int rows,
}) : srcSize = Vector2(
image.width / columns,
image.height / rows,
);
/// Compute the number of columns the image has
/// by using the image width and tile size.
int get columns => image.width ~/ srcSize.x;
/// Compute the number of rows the image has
/// by using the image height and tile size.
int get rows => image.height ~/ srcSize.y;
/// Gets the sprite in the position (row, column) on the sprite sheet grid.
///
/// This is lazily computed and cached for your convenience.
Sprite getSprite(int row, int column) {
return getSpriteById(row * columns + column);
}
/// Gets teh sprite with id [spriteId] from the grid.
///
/// The ids are defined as starting at 0 on the top left and going
/// sequentially on each row.
/// This is lazily computed and cached for your convenience.
Sprite getSpriteById(int spriteId) {
return _spriteCache[spriteId] ??= _computeSprite(spriteId);
}
Sprite _computeSprite(int spriteId) {
final i = spriteId % columns;
final j = spriteId ~/ columns;
return Sprite(
image,
srcPosition: Vector2Extension.fromInts(i, j)..multiply(srcSize),
srcSize: srcSize,
);
}
/// Creates a [SpriteAnimation] from this SpriteSheet, using the sequence
/// of sprites on a given row.
///
/// [from] and [to] can be specified to create an animation
/// from a subset of the columns on the row
SpriteAnimation createAnimation({
@required int row,
@required double stepTime,
bool loop = true,
int from = 0,
int to,
}) {
to ??= columns;
final spriteList = List<int>.generate(to - from, (i) => from + i)
.map((e) => getSprite(row, e))
.toList();
return SpriteAnimation.spriteList(
spriteList,
stepTime: stepTime,
loop: loop,
);
}
}
export 'src/spritesheet.dart';