Assets you need to sort out are:
Layer graphics
Layers contain static graphics, those that don't change or animate.
You can specify a flat colour for your background and overlay graphics on top of that using layers. Layers can be scrolled independently(in any direction and at any speed) and over laid on top of each other with altering the overall colouring or transparency. They can also be placed in front of all sprites on screen, so they appear in front of everything (like you might have on various HUD's).
Here is an example of a single layer graphic used on my Space Invaders high score screen as a static image and on the options screen as a scrolling image Invader back Image.
Each layer can be made up of several tiles (called a tile sheet) to form an image from a series common sized blocks (50x50 is the current default). You can for simplicity create a single large image and have this tiled onto a layer. A single graphic tiled for Space Invaders main game.
I hope to have a tiled graphics layer composer in the next version of the game engine to help with this task of placing tiles onto a layer.
Layers can be theoretically any size (the visible area is 800x600) , but the graphics cards cannot load any individual images larger than 2048x2048. They should be saved in PNG format only. You can then combine multiple images into one large background layer. Here are several large images (2000 pixels wide) which when joined back together make a layer 10,000 pixels wide! layerpart1, layerpart2, layerpart3,layerpart4, layerpart5
If you want any transparent areas on your layer graphics or sprites (you will definitely want this) you need to use a transparent background in your editing program.
Text sprites
Text sprites
There are several pre-defined fonts in the game engine, (fonts provided in game engine - you can create your own if you like place them on a separate tile sheet) these can be displayed in any colour and be made to appear transparent. But if you want to make some text (for game over, press start) that is multi coloured or highlights when selected you will need to use a graphics package to create these - make sure you pick a style and use it across all your text sprites (otherwise it will look naff). You should organise your text sprites onto a tile sheet(s). Example of Sprite Text from Space Invaders option screen. If you want to highlight text on menus one way is to do duplicates with a second highlighting colour (as shown in previous link).
Sprites
Sprites are any moving animating graphics. They are going to be the main and most time consuming graphics to produce. If you want to animate your sprites you will need to define separate graphics for each frame. Here is a simple sprite on a single tile sheet used for a title graphic.
These need to be organised onto a single graphic called a tile sheet. As mentioned above a tile sheet can be no larger than 2048x2048 pixels. If you need to create another tile sheet to fit your sprites on you can. Example tile sheet from Space Invaders. If as in this sheet you make your graphics white they can be dynamically coloured during the game. Please don't worry about making any sprites translucent as this can also be altered by the engine.
Make sure you define your graphic with a transparent background. Make sure if you don't have a graphics package at home such as Fireworks or Photoshop you should donwload GIMP
Sound effects
Sound effects are short noises, clicks, shooting sunds, clangs, explosions, words that are triggered throughout your game. You need to collect all of these over summer (or record them yourself).
You can download Audacity which is the program we use at College for editing audio.
Sound tracks
Be careful with long soundtracks that take up loads of space and take ages to load, try to edit any songs so they are no more than a minute or so long. Again use Audacity for this (you can do nice fade in and fade out effects).
