SpriteSheetBuilder Class
The SpriteSheetBuilder allows you to generate SpriteSheet instances at run time from any display object. This can allow you to maintain your assets as vector graphics (for low file size), and render them at run time as SpriteSheets for better performance.
SpriteSheets can be built either synchronously, or asynchronously, so that large SpriteSheets can be generated without locking the UI.
Note that the "images" used in the generated SpriteSheet are actually canvas elements, and that they will be sized to the nearest power of 2 up to the value of maxWidth or maxHeight.
Constructor
SpriteSheetBuilder
-
[framerate=0]
Parameters:
-
[framerate=0]Number optionalThe framerate of SpriteSheet instances that are created.
Item Index
Methods
Properties
Methods
_dispatchEvent
-
eventObj -
eventPhase
_drawNext
()
protected
Returns:
Boolean Returns false if this is the last draw.
_endBuild
()
protected
_fillRow
-
frames -
y -
img -
dataFrames -
pad
Returns:
The width & height of the row.
_run
()
protected
_startBuild
()
protected
addAnimation
-
name -
frames -
[next] -
[speed]
Adds an animation that will be included in the created SpriteSheet.
Parameters:
-
nameStringThe name for the animation.
-
framesArrayAn array of frame indexes that comprise the animation. Ex. [3,6,5] would describe an animation that played frame indexes 3, 6, and 5 in that order.
-
[next]String optionalSpecifies the name of the animation to continue to after this animation ends. You can also pass false to have the animation stop when it ends. By default it will loop to the start of the same animation.
-
[speed]Number optionalSpecifies a frame advance speed for this animation. For example, a value of 0.5 would cause the animation to advance every second tick. Note that earlier versions used
frequencyinstead, which had the opposite effect.
addEventListener
-
type -
listener -
[useCapture]
Adds the specified event listener. Note that adding multiple listeners to the same function will result in multiple callbacks getting fired.
Example
displayObject.addEventListener("click", handleClick);
function handleClick(event) {
// Click happened.
}Parameters:
-
typeStringThe string type of the event.
-
listenerFunction | ObjectAn object with a handleEvent method, or a function that will be called when the event is dispatched.
-
[useCapture]Boolean optionalFor events that bubble, indicates whether to listen for the event in the capture or bubbling/target phase.
addFrame
-
source -
[sourceRect] -
[scale=1] -
[setupFunction] -
[setupData]
Adds a frame to the SpriteSheet. Note that the frame will not be drawn until you call build method. The optional setup params allow you to have a function run immediately before the draw occurs. For example, this allows you to add a single source multiple times, but manipulate it or its children to change it to generate different frames.
Note that the source's transformations (x, y, scale, rotate, alpha) will be ignored, except for regX/Y. To apply transforms to a source object and have them captured in the SpriteSheet, simply place it into a Container and pass in the Container as the source.
Parameters:
-
sourceDisplayObjectThe source DisplayObject to draw as the frame.
-
[sourceRect]Rectangle optionalA Rectangle defining the portion of the source to draw to the frame. If not specified, it will look for a
getBoundsmethod, bounds property, ornominalBoundsproperty on the source to use. If one is not found, the frame will be skipped. -
[scale=1]Number optionalOptional. The scale to draw this frame at. Default is 1.
-
[setupFunction]Function optionalA function to call immediately before drawing this frame. It will be called with two parameters: the source, and setupData.
-
[setupData]Object optionalArbitrary setup data to pass to setupFunction as the second parameter.
Returns:
The index of the frame that was just added, or null if a sourceRect could not be determined.
addMovieClip
-
source -
[sourceRect] -
[scale=1] -
[setupFunction] -
[setupData] -
[labelFunction]
This will take a MovieClip instance, and add its frames and labels to this builder. Labels will be added as an animation running from the label index to the next label. For example, if there is a label named "foo" at frame 0 and a label named "bar" at frame 10, in a MovieClip with 15 frames, it will add an animation named "foo" that runs from frame index 0 to 9, and an animation named "bar" that runs from frame index 10 to 14.
Note that this will iterate through the full MovieClip with actionsEnabled
set to false, ending on the last frame.
Parameters:
-
sourceMovieClipThe source MovieClip instance to add to the SpriteSheet.
-
[sourceRect]Rectangle optional -
[scale=1]Number optionalThe scale to draw the movie clip at.
-
[setupFunction]Function optionalA function to call immediately before drawing each frame. It will be called with three parameters: the source, setupData, and the frame index.
-
[setupData]Object optionalArbitrary setup data to pass to setupFunction as the second parameter.
-
[labelFunction]Function optionalThis method will be called for each MovieClip label that is added with four parameters: the label name, the source MovieClip instance, the starting frame index (in the movieclip timeline) and the end index. It must return a new name for the label/animation, or
falseto exclude the label.
build
()
SpriteSheet
Builds a SpriteSheet instance based on the current frames.
Returns:
The created SpriteSheet instance, or null if a build is already running or an error occurred.
buildAsync
-
[timeSlice]
Asynchronously builds a SpriteSheet instance based on the current frames. It will
run 20 times per second, using an amount of time defined by timeSlice. When it is complete it will call the
specified callback.
Parameters:
-
[timeSlice]Number optionalSets the timeSlice property on this instance.
clone
()
SpriteSheetBuilder instances cannot be cloned.
dispatchEvent
-
eventObj -
[bubbles] -
[cancelable]
Dispatches the specified event to all listeners.
Example
// Use a string event
this.dispatchEvent("complete");
// Use an Event instance
var event = new createjs.Event("progress");
this.dispatchEvent(event);Parameters:
-
eventObjObject | String | EventAn object with a "type" property, or a string type. While a generic object will work, it is recommended to use a CreateJS Event instance. If a string is used, dispatchEvent will construct an Event instance if necessary with the specified type. This latter approach can be used to avoid event object instantiation for non-bubbling events that may not have any listeners.
-
[bubbles]Boolean optionalSpecifies the
bubblesvalue when a string was passed to eventObj. -
[cancelable]Boolean optionalSpecifies the
cancelablevalue when a string was passed to eventObj.
Returns:
Returns false if preventDefault() was called on a cancelable event, true otherwise.
hasEventListener
-
type
Indicates whether there is at least one listener for the specified event type.
Parameters:
-
typeStringThe string type of the event.
Returns:
Returns true if there is at least one listener for the specified event.
off
-
type -
listener -
[useCapture]
A shortcut to the removeEventListener method, with the same parameters and return value. This is a companion to the .on method.
IMPORTANT: To remove a listener added with on, you must pass in the returned wrapper function as the listener. See
on for an example.
on
-
type -
listener -
[scope] -
[once=false] -
[data] -
[useCapture=false]
A shortcut method for using addEventListener that makes it easier to specify an execution scope, have a listener only run once, associate arbitrary data with the listener, and remove the listener.
This method works by creating an anonymous wrapper function and subscribing it with addEventListener.
The wrapper function is returned for use with removeEventListener (or off).
IMPORTANT: To remove a listener added with on, you must pass in the returned wrapper function as the listener, or use
remove. Likewise, each time you call on a NEW wrapper function is subscribed, so multiple calls
to on with the same params will create multiple listeners.
Example
var listener = myBtn.on("click", handleClick, null, false, {count:3});
function handleClick(evt, data) {
data.count -= 1;
console.log(this == myBtn); // true - scope defaults to the dispatcher
if (data.count == 0) {
alert("clicked 3 times!");
myBtn.off("click", listener);
// alternately: evt.remove();
}
}Parameters:
-
typeStringThe string type of the event.
-
listenerFunction | ObjectAn object with a handleEvent method, or a function that will be called when the event is dispatched.
-
[scope]Object optionalThe scope to execute the listener in. Defaults to the dispatcher/currentTarget for function listeners, and to the listener itself for object listeners (ie. using handleEvent).
-
[once=false]Boolean optionalIf true, the listener will remove itself after the first time it is triggered.
-
[data]optionalArbitrary data that will be included as the second parameter when the listener is called.
-
[useCapture=false]Boolean optionalFor events that bubble, indicates whether to listen for the event in the capture or bubbling/target phase.
Returns:
Returns the anonymous function that was created and assigned as the listener. This is needed to remove the listener later using .removeEventListener.
removeAllEventListeners
-
[type]
Removes all listeners for the specified type, or all listeners of all types.
Example
// Remove all listeners
displayObject.removeAllEventListeners();
// Remove all click listeners
displayObject.removeAllEventListeners("click");Parameters:
-
[type]String optionalThe string type of the event. If omitted, all listeners for all types will be removed.
removeEventListener
-
type -
listener -
[useCapture]
Removes the specified event listener.
Important Note: that you must pass the exact function reference used when the event was added. If a proxy function, or function closure is used as the callback, the proxy/closure reference must be used - a new proxy or closure will not work.
Example
displayObject.removeEventListener("click", handleClick);stopAsync
()
Stops the current asynchronous build.
toString
()
String
Returns a string representation of this object.
Returns:
a string representation of the instance.
willTrigger
-
type
Indicates whether there is at least one listener for the specified event type on this object or any of its ancestors (parent, parent's parent, etc). A return value of true indicates that if a bubbling event of the specified type is dispatched from this object, it will trigger at least one listener.
This is similar to hasEventListener, but it searches the entire event flow for a listener, not just this object.
Parameters:
-
typeStringThe string type of the event.
Returns:
Returns true if there is at least one listener for the specified event.
Properties
framerate
Number
A framerate value that will be passed to new SpriteSheet instances that are created. If no framerate is specified (or it is 0), then SpriteSheets will use the Ticker framerate.
Default: 0
maxHeight
Number
The maximum height for the images (not individual frames) in the generated SpriteSheet. It is recommended to use a power of 2 for this value (ex. 1024, 2048, 4096). If the frames cannot all fit within the max dimensions, then additional images will be created as needed.
Default: 2048
maxWidth
Number
The maximum width for the images (not individual frames) in the generated SpriteSheet. It is recommended to use a power of 2 for this value (ex. 1024, 2048, 4096). If the frames cannot all fit within the max dimensions, then additional images will be created as needed.
Default: 2048
padding
Number
The padding to use between frames. This is helpful to preserve antialiasing on drawn vector content.
Default: 1
progress
Number
readonly
A value between 0 and 1 that indicates the progress of a build, or -1 if a build has not been initiated.
Default: -1
scale
Number
The scale to apply when drawing all frames to the SpriteSheet. This is multiplied against any scale specified in the addFrame call. This can be used, for example, to generate a SpriteSheet at run time that is tailored to the a specific device resolution (ex. tablet vs mobile).
Default: 1
spriteSheet
SpriteSheet
The SpriteSheet that was generated. This will be null before a build is completed successfully.
timeSlice
Number
A number from 0.01 to 0.99 that indicates what percentage of time the builder can use. This can be thought of as the number of seconds per second the builder will use. For example, with a timeSlice value of 0.3, the builder will run 20 times per second, using approximately 15ms per build (30% of available time, or 0.3s per second). Defaults to 0.3.
Default: 0.3
Events
complete
Dispatched when a build completes.