CPSceneObject

org.cosplay.CPSceneObject

abstract class CPSceneObject(id: String, tags: Set[String]) extends CPGameObject, CPLifecycle

Root type for all CosPlay scene objects.

Scene objects can be visible or invisible, have rectangular shape, have XY-coordinates of its left-top corner and Z-index. On each game frame and for each scene object the engine calls update method and, if object is visible and in frame, calls render method followed by calling all of its shaders.

Scene is a container for for scene objects. Scene objects can be added or removed from the scene dynamically via CPSceneObjectContext instance passed to update and render methods. Note that all scenes should have at least one scene object. In CosPlay there is no hierarchy of scene objects in the scene - all scene objects form a simple flat structure inside of the scene. Just like with any other game objects, you can use tags to organize scenes and scene objects.

Generally, you would use one of many existing scene object subclasses like the various sprites provided out-of-the-box. You can, however, just as easily subclass this class directly and provide the necessary implementation. At the minimum you need to implement all abstract methods and at least one of either render or update methods.

Here's a basic minimal scene object implementation that prints "Hello CosPlay!" text at (0,0) coordinate in black color:

object HelloSprite extends CPSceneObject("id"):
   override def getX: Int = 0
   override def getY: Int = 0
   override def getZ: Int = 0
   override def getDim: CPDim = CPDim(15, 1)
   override def render(ctx: CPSceneObjectContext): Unit =
       ctx.getCanvas.drawString(0, 0, 0, "Hello CosPlay!", CPColor.C_BLACK)

If scene object is invisible than only update method will be called on each frame. If object is visible and in camera frame - method render will be called as well to render itself. Note that shaders are called always, regardless of whether the object visible, in camera frame or invisible.

Note that shader pass consists of two phases:

In the 1st phase shaders for all visible scene objects are processed
In the 2nd phase shaders for all invisible scene objects are processed. This allows to minimize the interference between object shaders and full-screen shaders that are typically attached to the off-screen sprite that is invisible.

Value parameters

id: Optional ID of this scene object. By default, the random 6-character ID will be used.
tags: Optional set of organizational or grouping tags. By default, the empty set is used.

Attributes

See also: CPDynamicSprite
Source: CPSceneObject.scala
Graph
Supertypes: trait CPLifecycle

class CPGameObject

class Object

trait Matchable

class Any
Known subtypes: class CPCanvasSprite

class CPDynamicSprite

class CPAnimationSprite

class CPImageSprite

class CPBubbleSprite

class CPCenteredImageSprite

class CPLabelSprite

class CPListBoxSprite

class CPSpacerSprite

class CPTextInputSprite

class CPTitlePanelSprite

class CPVideoSprite

class CPOffScreenSprite

class CPKeyboardSprite

class CPLayoutSprite

class CPSingletonSprite

class CPParticleSprite

class CPStaticImageSprite
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Members list

Value members

Abstract methods

Gets current dimension (width and height) of this object.

Attributes

See also: getWidth

getHeight

getRect
Source: CPSceneObject.scala

Gets current X-coordinate of this object within dimensions of its scene. Note that returned value is allowed to be outside scene's dimension (e.g. negative value). In such cases, the clipping of the scene rendering will result in showing only portion or none of the object.

Attributes

Source: CPSceneObject.scala

Gets current Y-coordinate of this object within dimensions of its scene. Note that returned value is allowed to be outside scene's dimension (e.g. negative value). In such cases, the clipping of the scene rendering will result in showing only portion or none of the object.

Attributes

Source: CPSceneObject.scala

Gets Z-index or order to use in rendering of this object. A pixel with higher Z-index visually overrides the overlapping pixel in the same XY-coordinate with equal or smaller Z-index.

Attributes

Source: CPSceneObject.scala

Concrete methods

Gets optional collision shape or hit box for this sprite.

Attributes

Returns: Optional collision shape, None if this sprite does not support collisions.
See also: CPSceneObjectContext.collisions
Source: CPSceneObject.scala

Gets current height of this object.

Attributes

See also: getWidth

getDim
Source: CPSceneObject.scala

Gets rectangular shape of this sprite. It is basically a combination of its top-left corner XY-coordinate and sprite's dimension.

Attributes

See also: getX

getY

getDim
Source: CPSceneObject.scala

Gets the optional list of shaders attached to this scene object. By default, returns an empty list. Note that shaders are called regardless of whether the object visible, in camera frame or invisible.

Attributes

Source: CPSceneObject.scala

Gets current width of this object.

Attributes

See also: getHeight

getDim
Source: CPSceneObject.scala

Gets last X-coordinate which is

getX + getWidth - 1

. Note the value when the width is zero.

Attributes

Returns: Last X-coordinate for this sprite.
Source: CPSceneObject.scala

Gets last Y-coordinate which is

getY + getHeight - 1

. Note the value when the height is zero.

Attributes

Returns: Last Y-coordinate for this sprite.
Source: CPSceneObject.scala

Shortcut method for hiding this object. Note that by default all scene objects are visible. Note also that this change happens immediately in the same frame. If you want this to happen in the next frame only you need to use CPSceneObjectContext.runNextFrame.

Attributes

See also: setVisible

CPSceneObjectContext.runNextFrame

CPSceneObjectContext.runLater
Source: CPSceneObject.scala

Checks the visibility flag.

If object is invisible than only update method will be called on each frame. If object is visible and in camera frame - method render will be called as well to render itself. Note that shaders are called regardless of whether the object visible, in camera frame or invisible.

Attributes

See also: show

hide

setVisible
Source: CPSceneObject.scala

Called after all scene objects have been updated but before any of them were rendered. It allows, for example, to rearrange UI sprites on the screen after all of them had a chance to update their dimensions but before they are actually rendered on the screen. Essentially, it provides for "post-update, pre-render" notification. The order in which scene objects are called is undefined.

Note that in most cases one should not override this callback. It is only meant for the use cases when one needs to be notified when all scene objects to be updated but before any of them are rendered. Default implementation is no-op. No rendering should be done in this callback.

Default implementation is no-op.

Value parameters

ctx: Frame context. This context provides bulk of functionality that a scene object can do in a game, e.g. interact with other scene objects, check collisions, read input events and manage input focus, add or remove scene objects, add new and switch between scenes, etc.

Attributes

See also: render

update
Source: CPSceneObject.scala

Called to render this scene object. Only visible and in camera frame objects will receive this callback. This callback is called on scene object after all scene objects received update and monitor callbacks. Note that unlike update and monitor callbacks and shaders that are called for all scene objects on each frame, this callback is only called for scene objects that are visible and, at least partially, in camera frame. The order in which scene objects are called is undefined.

Note that generally this callback should not modify scene object state (which should be done in either update or monitor callbacks.

Default implementation is no-op.

Value parameters

ctx: Frame context. This context provides bulk of functionality that a scene object can do in a game, e.g. interact with other scene objects, check collisions, read input events and manage input focus, add or remove scene objects, add new and switch between scenes, etc.

Attributes

See also: update

monitor

isVisible
Source: CPSceneObject.scala

Sets visibility flag. Note that by default all scene objects are visible. Note also that this change happens immediately in the same frame. If you want this to happen in the next frame only you need to use CPSceneObjectContext.runNextFrame.

Value parameters

vis: true to make this object visible, false otherwise.

Attributes

See also: show

hide

CPSceneObjectContext.runNextFrame

CPSceneObjectContext.runLater
Source: CPSceneObject.scala

Shortcut method for showing this object. Note that by default all scene objects are visible. Note also that this change happens immediately in the same frame. If you want this to happen in the next frame only you need to use CPSceneObjectContext.runNextFrame.

Attributes

See also: setVisible

CPSceneObjectContext.runNextFrame

CPSceneObjectContext.runLater
Source: CPSceneObject.scala

Called to update the internal state of this scene object. This callback is called each frame on every object in the scene and it is called before any render callback. Note that all scene object will receive this callback before first render callback. The order in which scene objects are called is undefined.

Default implementation is no-op. No rendering should be done in this callback.

Value parameters

ctx: Frame context. This context provides bulk of functionality that a scene object can do in a game, e.g. interact with other scene objects, check collisions, read input events and manage input focus, add or remove scene objects, add new and switch between scenes, etc.

Attributes

See also: render

monitor

isVisible
Source: CPSceneObject.scala

Inherited methods

Compares the receiver object (this) with the argument object (that) for equivalence.

Any implementation of this method should be an equivalence relation:

It is reflexive: for any instance x of type Any, x.equals(x) should return true.
It is symmetric: for any instances x and y of type Any, x.equals(y) should return true if and only if y.equals(x) returns true.
It is transitive: for any instances x, y, and z of type Any if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.

If you override this method, you should verify that your implementation remains an equivalence relation. Additionally, when overriding this method it is usually necessary to override hashCode to ensure that objects which are "equal" (o1.equals(o2) returns true) hash to the same scala.Int. (o1.hashCode.equals(o2.hashCode)).

Value parameters

that: the object to compare against this object for equality.

Attributes

Returns: true if the receiver object is equivalent to the argument; false otherwise.
Definition Classes: CPGameObject -> Any
Inherited from:: CPGameObject
Source: CPGameObject.scala

Gets unique ID of this game object.

Attributes

Inherited from:: CPGameObject
Source: CPGameObject.scala

Gets current lifecycle state.

Attributes

Inherited from:: CPLifecycle
Source: CPLifecycle.scala

Gets optional set of organizational tags. Note that by default the set of tags is empty.

Attributes

See also: CPSceneObjectContext.getObjectsForTags
Inherited from:: CPGameObject
Source: CPGameObject.scala

Callback on lifecycle object activation. Default implementation is no-op.

Attributes

See also: CPLifecycle.State.LF_ACTIVE
Inherited from:: CPLifecycle
Source: CPLifecycle.scala

Callback on lifecycle object deactivation. Default implementation is no-op.

Attributes

See also: CPLifecycle.State.LF_INACTIVE
Inherited from:: CPLifecycle
Source: CPLifecycle.scala

Callback on lifecycle object start. Default implementation is no-op.

Attributes

See also: CPLifecycle.State.LF_STARTED
Inherited from:: CPLifecycle
Source: CPLifecycle.scala

Callback on lifecycle object stop. Default implementation is no-op.

Attributes

See also: CPLifecycle.State.LF_STOPPED
Inherited from:: CPLifecycle
Source: CPLifecycle.scala

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