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

allocatedCount → int: The total number of allocated handles.
no setter
atlas ↔ Image: The atlas used by the SpriteBatch.
getter/setter pair
colors → UnmodifiableListView<Color>: 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 on web.
final
defaultTransform → RSTransform?: The default transform, used when a transform was not supplied for a BatchItem.
final
freeCount → int: The number of free handles.
no setter
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
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>: no setter
transforms → UnmodifiableListView<RSTransform>: no setter
useAtlas → bool: Whether to use Canvas.drawAtlas or not.
final
usedCount → int: The number of used handles.
no setter
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}) → int: Add a new batch item.
addTransform({required Rect source, RSTransform? transform, bool flip = false, Color? color}) → int: Add a new batch item using a RSTransform.
clear() → void: Clear the SpriteBatch so it can be reused.
getBatchItem(int index) → BatchItem: Gets the BatchItem at the given index.
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
removeAt(int index) → void: Removes the batch item at the given index.
render(Canvas canvas, {BlendMode? blendMode, Rect? cullRect, Paint? paint}) → void
replace(int index, {Rect? source, Color? color, RSTransform? transform}) → void: Replaces the parameters of the batch item at the given index. At least one of the parameters must be different from null.
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.