PupTent is not ready for public consumption. It's likely to change quite a bit. But I want to share it with some friends, so here it is.
PupTent - a 2D game engine built on Cinder and entityx
PupTent is meant for use in the development of small games with big hearts. It is especially supportive of mixing procedural and hand-drawn 2d art.
By providing basic systems, PupTent lets you get start coding your gameplay systems without a lot of set up. If you want to change how something works later, feel free to swap in your own System. The component architecture means that it's easy to replace one system with another. Systems only know about components, and components only know about themselves. Locus and RenderMesh are the only components used by multiple systems.
The basic idea of an entity-system game is to create all of your in-game entities as collections of components. PupTent provides some useful base components and systems for handling things like animation, entity lifetime, and rendering. For custom in-game behavior, you can attach a ScriptComponent to any entity, which calls a function and provides information about the entity and scene. If you want to use other information in your script (like keyboard input), just capture it in the lambda you pass to the ScriptComponent.
If you want to have some code that doesn't belong to any one entity, there is no need to shoehorn it into the entity system. If you were making a game of Go, for example, the player's control and computer AI code would likely live outside of the entity system. The entities would be things like the pieces on the board and the board itself. The control code would edit the appropriate entities' positions based on what the user selected. To define what could be selected, however, you might create a Selectable component and apply it to anything that the player will then be allowed to grab and move around. Making the controls a System in entityx just gives you easy access to the event and update mechanisms within the framework.
Features (Existing and Planned):
Simple 2d spatial transformations
- Attach a Locus component for access to
- Registration point
Quick batch renderer for 2d geometry
- Attach a RenderMesh component to store triangle_strip vertices
- RenderSystem batches all meshes into a single draw call
- Each entity's RenderMesh verticies are transformed by its Locus
- A single render pass makes the GPU driver happy
- Note that means all sprites should packed into one texture
- Cinder provides great support for any additional drawing you might want to do
Texture Packing (and atlasing)
- TextureAtlas loads and stores sprite information
- TexturePacker (in pockets) automates sprite sheet building and allows for offline and runtime asset packing
Sprite animation, loading from disk
- Add a SpriteAnimation component to update RenderMesh with animation frames
- Simple JSON description format for both sprites and animations
- ScriptComponent executes arbitrary c++ functions on Entities
- (TODO eventually) Lua scripting support
(Incomplete) Physics system
- PhysicsComponent updates the Locus based on Box2D physics simulation
- (TODO) callbacks on collision
- (TODO) sensors
- Background layer rendering with parallax (BackgroundSystem)
- Panning/zooming camera(s)
- Sound effect and music playback (SoundSystem, hopefully atop Cinder...)
- Locus & POV component, way of promoting one as "main" view
- (Longer term) Entity editor
- (Longer term) World editor
- Line and path expansion
- Line between e.g. two Locii
- LineComponent modifies Mesh to draw a line
typedef std::shared_ptr<T> TRef; typedef std::unique_ptr<T> TUniqueRef; typedef std::weak_ptr<T> TWeakRef;
PupTent has only been tested on Mac OSX 10.8. Support is planned for iOS 6.0+. Windows 7 will be next, assuming VS2012 has the C++11 support needed. Android is the final target, pending Cinder support (I’m looking at https://github.com/safetydank/Cinder/tree/android-dev/android)