SpriteBatch class

The SpriteBatch API allows for rendering multiple items at once.

This class allows for optimization when you want to draw many parts of an image onto the canvas. It is more efficient than using multiple calls to Canvas.drawImageRect and provides more functionality by allowing each BatchItem to have their own transform rotation and color.

By collecting all the necessary transforms on a single image and sending those transforms in a single batch to the GPU, we can render multiple parts of a single image at once.

Note: If you are experiencing problems with ghost lines, the less performant Canvas.drawImageRect can be used instead of Canvas.drawAtlas. To activate this mode, pass in useAtlas = false to the constructor or load method that you are using and each BatchItem will be rendered using the Canvas.drawImageRect method instead.

Constructors

SpriteBatch(Image atlas, {RSTransform? defaultTransform, bool useAtlas = true, Color? defaultColor, BlendMode? defaultBlendMode, Images? imageCache, String? imageKey})

Properties

atlas ↔ Image: The atlas used by the SpriteBatch.
getter/setter pair
colors → UnmodifiableListView<Color>: The colors list shouldn't be modified directly, that is why an UnmodifiableListView is used. If you want to add colors use the add or addTransform method.
no setter
defaultBlendMode → BlendMode?: The default blend mode, used for blending a batch item.
final
defaultColor → Color?: The default color, used as a background color for a BatchItem.
final
defaultTransform → RSTransform?: The default transform, used when a transform was not supplied for a BatchItem.
final
hashCode → int: The hash code for this object.
no setterinherited
height → int: The height of the atlas.
no setter
imageCache → Images: When the _imageCache isn't specified, the global Flame.images is used.
no setter
imageKey → String: When the _imageKey isn't specified imageKey will return either the key for the atlas stored in imageCache or a key generated from the identityHashCode.
no setter
isEmpty → bool: Does this batch contain any operations?
no setter
length → int: no setter
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
size → Vector2: The size of the atlas.
no setter
sources → UnmodifiableListView<Rect>: The sources list shouldn't be modified directly, that is why an UnmodifiableListView is used. If you want to add sources use the add or addTransform method.
no setter
transforms → UnmodifiableListView<RSTransform>: The transforms list shouldn't be modified directly, that is why an UnmodifiableListView is used. If you want to add transforms use the add or addTransform method.
no setter
useAtlas → bool: Whether to use Canvas.drawAtlas or not.
final
width → int: The width of the atlas.
no setter

Methods

add({required Rect source, double scale = 1.0, Vector2? anchor, double rotation = 0, Vector2? offset, bool flip = false, Color? color}) → void: Add a new batch item.
addTransform({required Rect source, RSTransform? transform, bool flip = false, Color? color}) → void: Add a new batch item using a RSTransform.
clear() → void: Clear the SpriteBatch so it can be reused.
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
render(Canvas canvas, {BlendMode? blendMode, Rect? cullRect, Paint? paint}) → void
replace(int index, {Rect? source, Color? color, RSTransform? transform}) → void: Replace provided values of a batch item at the index, when a parameter is not provided, the original value of the batch item will be used.
toString() → String: A string representation of this object.
inherited

Operators

operator ==(Object other) → bool: The equality operator.
inherited

Static Methods

load(String path, {RSTransform? defaultTransform, Images? images, Color? defaultColor, BlendMode? defaultBlendMode, bool useAtlas = true}) → Future<SpriteBatch>: Takes a path of an image, and optional arguments for the SpriteBatch.