The following are guidelines that you should consider when programming games:
- Games should be playable with joystick alone. All menus and such should be possible to select using joystick alone. This allows the game to be played on GX4000 for example and to play it without needing to press a key. It could be also selectable with number keys or arrows.
- 'P' key should be used for pause in joystick control mode. This makes it compatible with the GX4000. It's pause button is mapped to the 'P' key.
- Both digital joysticks should be selectable to use. The Amstrad plus has both connectors, the CPC can have a second joystick using a joystick splitter or using one of the official Amstrad Joysticks.
- Analogue joystick on Plus should be selectable if Plus machine is used. You can detect if a Plus machine exists programatically. Analogue joystick can be used as an alternative to a digital joystick (this avoids "Keyboard Clash" when used in 2 player games in conjunction with keyboard or another digital joystick) or to their full analogue ability where it makes sense in the game.
- It should be possible to select "No Sound", "Music", "Sound Effects" or "Music and Sound Effects" (where possible).
- If you are using overscan, consider that the position of the screen may not be the same on all monitors, so a method to centralise it before the game starts, or in the options of the game.
- It should be possible to redefine the keys to the choice the user wants, or to be able to choose from a preset list.
Good presets:
Directions = Up, Down, Left, Right
Directions: Cursors Fire: Space OR copy
Directions: Q, A, O, P Fire: Space
- Games should support the FIRE 2 button for gamepads/joysticks. Maybe the player character needs to be able to jump, and then UP is used for this. And that is ok. Just don't forget to include the FIRE 2 button for jumping as well.
- Consider supporting AMX Mouse (or compatibles such as Bryce's USB mouse hardware) and Symbiface 2 Mouse where it makes sense in the game. Movement could also be used for moving to the wanted menu item and clicking the mouse button to select.
- The user should be able to choose the type of monitor. This will enable the game to adjust its colors to either a color monitor or a green / monochrome monitor.
- A game should provide a high score list (if it makes sense) and save it to disc.
- The availability of memory expansions should be investigated. And if additional memory is found the game shall use it in some way. Examples are to add additional features or to load all levels at one at the beginning.