#include <IGameObject.h>

Inheritance diagram for JadeEngine::IGameObject:

Public Member Functions
	IGameObject ()

virtual void	Update ()

virtual void	Clean ()

virtual LoadState	Load (SDL_Renderer *renderer)

virtual void	Render (SDL_Renderer *renderer)

LoadState	GetLoadState () const

void	SetLoadState (const LoadState newState)

bool	IsShown () const

virtual void	Show (const bool show)

int32_t	GetZ () const

void	Destroy ()

bool	DestructionWanted () const

Public Attributes
const std::shared_ptr< Transform >	transform

Protected Attributes
LoadState	_loadState

bool	_shown

int32_t	_z

Detailed Description

Interface for game objects.

The most basic building block of Jade Engine, game objects are objects that live inside a scene and can be updated and rendered every frame.

Additionally game objects can be used to compose simple game objects into more advanced ones. For example a Button game object will have collection of Sprite game objects for various pressed states and a Text game objects.

When creating new game objects based on IGameObject it is necessary to create a constructor that accepts only one argument: constant reference to creation structure which will contain at the very least ObjectLayer layer; member. See following example:

#include "IGameObject.h"
#include "ObjectLayer.h"
 
using namespace JadeEngine;
 
namespace JadeEngine
{
  class Sprite;
}
 
struct SomeObjectParams
{
  ObjectLayer layer; // Required
  // Other parameters necessary to initialize the _childSprite and other child objects
};
 
class SomeObject : public IGameObject
{
public:
  SomeObject(const SomeObjectParams& cardParams); // Create _childSprite and other child objects in here
  void Update() override; // Perform frame logic here
private:
  Sprite* _childSprite;
};

See also: IScene, Game::Create

Constructor & Destructor Documentation

◆ IGameObject()

JadeEngine::IGameObject::IGameObject ( )

inline

Default constructor for game object.

Member Function Documentation

◆ Clean()

virtual void JadeEngine::IGameObject::Clean ( )

inlinevirtual

Triggered when the game object is about to be destroyed or reset.

All resources belonging solely to the game object, such as textures, should be released at this point. The game object instance itself may or may not be destroyed after this callback.

Reimplemented in JadeEngine::Sprite, JadeEngine::Text, and JadeEngine::TextBox.

◆ Destroy()

void JadeEngine::IGameObject::Destroy ( )

inline

Mark the object to be destroyed.

At the begging of the next frame its Clean function will be called and the game object will removed from list of game objects.

◆ DestructionWanted()

bool JadeEngine::IGameObject::DestructionWanted ( ) const

inline

Returns whether the object is marked for destruction.

◆ GetLoadState()

LoadState JadeEngine::IGameObject::GetLoadState ( ) const

inline

Return the current load state of the game object.

See also: LoadState

◆ GetZ()

int32_t JadeEngine::IGameObject::GetZ ( ) const

inline

Returns Z coordinate. The game objects with higher Z coordinate will be drawn over the ones with lower one.

◆ IsShown()

bool JadeEngine::IGameObject::IsShown ( ) const

inline

Returns whether game object is currently shown.

Only shown objects are rendered and have their Render function triggered.

See also: IGameObject::Show, IGameObject::Render

Returns: true if the object is shown, false otherwise.

◆ Load()

virtual LoadState JadeEngine::IGameObject::Load ( SDL_Renderer * renderer )

inlinevirtual

Triggered every frame when GetLoadState function returns kLoadState_Wanted to allow resources, such as textures, to be loaded.

The trigger order is the following: IScene::PreUpdate -> IGameObject::Load -> IGameObject::Update -> IScene::Update -> IGameObject::Load -> IGameObject::Render.

Parameters

renderer The engine's SDL2 renderer that can be used to create resources.

Returns: The function must return the load state that reflects the result of the load operation. It will be used in SetLoadState function by the Game class.

See also: GetLoadState

Reimplemented in JadeEngine::TextSprite, JadeEngine::TextBox, and JadeEngine::Text.

◆ Render()

virtual void JadeEngine::IGameObject::Render ( SDL_Renderer * renderer )

inlinevirtual

Triggered every frame while the scene that owns this game object is active, the game object was successfully loaded and the game object is shown.

The trigger order is the following: IScene::PreUpdate -> IGameObject::Load -> IGameObject::Update -> IScene::Update -> IGameObject::Load -> IGameObject::Render.

Parameters

renderer The engine's SDL2 renderer that should be used to render the game object.

See also: IGameObject::Update, LoadState, IGameObject::IsShown

Reimplemented in JadeEngine::Sprite, JadeEngine::LineStrip, JadeEngine::TextSprite, JadeEngine::TextBox, JadeEngine::Text, and JadeEngine::BoxSprite.

◆ SetLoadState()

void JadeEngine::IGameObject::SetLoadState ( const LoadState newState )

inline

Set the load state to a new value.

See also: LoadState

◆ Show()

virtual void JadeEngine::IGameObject::Show ( const bool show )

inlinevirtual

Show or hide game object.

Warning: This does not affect any owned child game objects as this interface has no knowledge of them. It only handles tracking the visibility state. It is recommended to override this function for game object that own other game objects. Inside the overridden function one should call this - base - function and handle hiding/showing of children game objects there.
void SomeGameObject::Show(const bool shown) //override

{

IGameObject::Show(shown);

// Show or hide any child objects or perform any other necessary operations

_childObject->Show(IsShown());

}