Input system

Handling inputs from keyboard and mouse are ready. At this point I could use my little engine for some 2d game. And I will use it ;), but right now I have exams at my university so I can't spend much time on programming.

Animation of sprites

Today I have implemented sprites animation. I can read an animation sequence from file and display it on screen. I also have implemented mouse input and tomorrow I will work on keyboard. When this is done I will have a basic 2d engine ready (it's based on opengl so adding 3d in the future will not be a problem) and I will be able to start working on my next game :) .

Sprites

I have implemented displaying sprites on screen, sprite can be any size. The sprite on the test image has nothing do to with the game I'm inventing, it's just for testing purposes. Next step will be animated sprite with frame sequences.

As you can see on this screen, my next game will be called "Plastus".

Loading of textures

Not much to write today. Because of wedding in my family, I have only managed to add support for texture loading, my next step will be adding functionality of displaying sprites on screen.

State Manager

Today I have added support for game states such as gameState, menuState etc. Actually there are two classes:

• StateManager which is singleton and has such functions as pushState, popState, changeState
• State which is abstract class with abstract functions : onEnter, onExit, onUpdate, onDraw, onInput

StateManager is holding stack of states and is calling states from bottom to top, this way I can have gameState to draw it's state and then pauseState or inGameMenuState to draw its content.

Initialization of game window

I've done part responsible for initialization of game window and game loop. I have to admit that this time I have borrowed some ideas from JMonkey engine.

I wanted to paste here UML diagram but blogger don't want to upload my images and I don't know why* :(

Anyway I have AbstractGame class, which has abstract functions such as start, render, update, initialize, and VariableTimestepGame which implements this functions.



Before the window is created, application shows dialog with options regarding screen res, depth buffer, screen frequency and fullscreen/windowed mode.


*it's working now so I will upload some images

Parts of Engine

A Game engine is a bunch of code what works from behind the scene and responds to commands from the game code. For example game tells engine to create a game window, to draw an image on the screen, to play some sounds. The game engine is some kind of helper library for the game.

When creating such engine first problem is how to organize it's internals into logical subsystems. We need rendering subsystem, input subsystem, sound subsystem, sometimes physics subsystem and something responsible for the game loop. When I will create my engine I will probably start with subsystem responsible for creating game window and game loop, then I will concentrate on rendering and inputs. Last stage will be creating functionality to play sounds.