Libgdx Scene2d Actor System Overview Diagram

01-libgdx-sprite.md

• most basic way to display(draw) an image onscreen
• can be done with either Stateless(Texture, TextureRegion) or Stateful(Sprite)
• with the Stateless(Texture, TextureRegion) approach -> you need to specify the x,y coordinates on each draw call
• with the Stateful(Sprite) approach -> the needed x,y coordinates are saved into the Sprite object itself

01-libgdx-sprite.svg

02-libgdx-actor.md

• Actor extends Sprite and allows for additional functionality like mouse hover/click
• the (optional) Skin can be used to modify the viewing part the Actor actor depending on the actors state. Example: Button class changes the image if it is hovered, clicked, disabled, etc and the ButtonStyle allows to define a different image for each state
• allows the usage of Actions -> to manipulate/animate(move,flip,etc..) Actors on the Stage

02-libgdx-actor.svg

03-libgdx-layout.md

• allows to put together different Widgets(Buttons,Labels,etc) into WidgetGroups(Table,VerticalGroup,Stack,etc) to define an UI

03-libgdx-layout.svg

04-libgdx-00-files.md

• the graphiz dot files
• can be easely edited for example with the atom editor and graphviz-preview-plus plugin

04-libgdx-01-sprite.dot

digraph "libgdx-sprite" {

FileSystem -> Image
FileSystem -> Json
Image -> Texture [label="load/convert to opengl image"]
Image -> TextureAtlas
Json -> TextureAtlas [label="how the image is divided"]
Texture -> TextureAtlas [label="packed version"]
Texture -> TextureRegion [label="(may) consists of"]
TextureAtlas -> AtlasRegion [label="consists of"]

TextureRegion -> AtlasRegion [label="with entpacking info"]

Texture -> Sprite
TextureRegion -> Sprite
AtlasRegion -> AtlasSprite
Sprite -> AtlasSprite [label="extended"]

Functionality -> Stateless, Stateful
Stateless -> TextureRegion [label="Draw"]
Stateless -> Texture [label="Draw"]
Stateless -> Stateful [label="Draw"]
Stateful -> Sprite [label="Position,Scale,Rotate"]

{ rank=same Image Json}
{ rank=same Functionality Texture TextureAtlas}
{ rank=same TextureRegion AtlasRegion Stateless}
{ rank=same Sprite AtlasSprite Stateful}
}

04-libgdx-02-actor.dot

digraph "libgdx-actor" {

FileSystem -> Image
FileSystem -> Json
FileSystem -> Font
Json, Font,TextureAtlas -> Skin
Image -> Texture [label="load/convert to opengl image"]
Image -> TextureAtlas [label="load"]
Json -> TextureAtlas [label="how the image\n is divided"]

Texture -> TextureAtlas [label="packed version"]
Texture -> TextureRegion [label="consists of"]
TextureAtlas -> AtlasRegion [label="consists of"]
TextureRegion -> AtlasRegion [label="with entpacking info"]

Texture -> Sprite
TextureRegion -> Sprite
AtlasRegion -> AtlasSprite
Sprite -> AtlasSprite [label="extended"]

Sprite -> SpriteDrawable
AtlasSprite -> SpriteDrawable
TextureRegion, AtlasRegion -> TextureRegionDrawable, NinePatchDrawable

TextureRegionDrawable -> Drawable
SpriteDrawable -> Drawable
NinePatchDrawable -> Drawable

Skin -> SkinStyle [label="consists of"]
Drawable -> SkinStyle -> Actor
Game -> Stage
Camera -> Viewpoint -> Stage
Group -> Stage
Stage -> Actor

Functionality -> Stateless, Stateful
Stateless -> TextureRegion [label="Draw"]
Stateless -> Texture [label="Draw"]
Stateful -> Sprite [label="Position,Scale,Rotate"]
Stateful -> Actor [label="mouseOver, onClick"]

{ rank=same Image Json Font}
{ rank=same Texture TextureAtlas Skin}
{ rank=same TextureRegion AtlasRegion }
{ rank=same Sprite AtlasSprite }
{ rank=same TextureRegionDrawable SpriteDrawable NinePatchDrawable }
}

04-libgdx-03-layout.dot

digraph "libgdx-layout" {

FileSystem -> Image
FileSystem -> Json
FileSystem -> Font
Json, Font,TextureAtlas -> Skin

Image -> Texture [label="load/convert to opengl image"]
Image -> TextureAtlas [label="load"]
Json -> TextureAtlas [label="how the image\n is divided"]

Texture -> TextureAtlas [label="packed version"]
Texture -> TextureRegion [label="consists of"]
TextureAtlas -> AtlasRegion [label="consists of"]
TextureRegion -> AtlasRegion [label="with entpacking info"]

Texture -> Sprite
TextureRegion -> Sprite
AtlasRegion -> AtlasSprite
Sprite -> AtlasSprite [label="extended"]

Sprite -> SpriteDrawable
AtlasSprite -> SpriteDrawable
TextureRegion, AtlasRegion -> TextureRegionDrawable, NinePatchDrawable

TextureRegionDrawable -> Drawable
SpriteDrawable -> Drawable
NinePatchDrawable -> Drawable# [label="better resizing"]

Skin -> SkinStyle [label="consists of"]
Drawable -> SkinStyle -> Actor
Actor -> Button,Label,TextField
Game -> Stage
Camera -> Viewpoint -> Stage
Group -> Stage
Group -> WidgetGroup

Functionality -> Stateless, Stateful
Stateless -> TextureRegion [label="Draw"]
Stateless -> Texture [label="Draw"]
Stateless -> Stateful [label="Draw"]
Stateful -> Sprite [label="Position,Scale,Rotate"]
Stateful -> Actor [label="mouseOver, onClick"]
Stateful -> WidgetGroup [label="layout"]

Stage -> WidgetGroup
Actor -> WidgetGroup [label="extended"]
WidgetGroup -> Table,VerticalGroup,Stack

Button,Label,TextField -> UI
Table,VerticalGroup,Stack -> UI

{ rank=same Image Json Font}
{ rank=same Texture TextureAtlas Skin}
{ rank=same TextureRegion AtlasRegion }
{ rank=same Sprite AtlasSprite }
{ rank=same TextureRegionDrawable SpriteDrawable NinePatchDrawable }
#{ rank=same WidgetGroup Actor}
{ rank=same Table,VerticalGroup,Stack Button,Label,TextField}
}