The run-time engine
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Owning entry: Contents
The engine (also called the "interpreter") is what runs your game and is what the end player will use.
If you are using the default interface, then you use the right mouse button to cycle between the available 'modes', and the left button to use the current mode on the mouse position. You can also move the mouse to the top of the screen to bring up the icon bar where you can directly select a mode. To exit the engine, press Ctrl-Q. You can save your game position using F5 and restore with F7.
The controls described above work with the default setup; however, you can customize your game to use a different interface and shortcut keys.
The demo game
The first thing you'll probably want to do is to run the demo game. This game will try to show you some of what AGS can do.
To run the demo, choose the "Open the Demo Game" option from the AGS folder in your start menu. If you're looking for the files, they're located in the All Users Application Data folder (this is for compatibility with Windows Vista's new security filters).
NOTE: The demo game is currently under development. It has various unfinished or unimplemented areas.
Graphics driver selection
AGS has two different graphics drivers when run on Windows -- DirectDraw and Direct3D. DirectDraw is the 'classic' software graphics driver, that AGS has used ever since the initial Windows version was released. It's perfectly fine for simple games that don't use many large sprites, tinting or alpha blending. It's also quite fast at doing RawDrawing to the screen.
Direct3D is a new, hardware accelerated graphics driver. It uses the Direct3D 9.0 to render the game in a fully hardware-accelerated environment. This means that the game will run a lot faster if you use features such as alpha blending and tinting, which are quite slow to perform in software mode. However, with Direct3D doing RawDraw operations can be quite slow, and the driver won't work on all graphics cards.
No matter which you choose as your default graphics driver, the player can always run the Setup program and switch to using the other driver if they are having problems on their PC.
System Requirements
DirectDraw: any Windows-based PC with DirectX 5 or later installed
Direct3D: any Windows-based PC with DirectX 9.0 installed and a graphics card designed for DirectX 8.1 or later (most cards manufactured from 2003 onwards).
If you get the error message "Graphics card does not support Pixel Shader 1.4" on startup, this indicates that your graphics card is too old to run with the Direct3D driver. You should choose the DirectDraw driver instead.
See Also: System.HardwareAcceleration property
Run-time engine setup
The engine Setup program allows the player to customize certain game settings.
Firstly, they can change the game resolution. If they do so, all your game graphics will automatically be stretched or shrunk to fit, and the option is a handy way for the player to start the game if their system won't run at the default resolution for some reason.
They can also select to run the game in a window on the desktop rather than full-screen. This will take a performance hit though, so it's always preferable to run full-screen.
The "Use 85 Hz display" option sets the monitor refresh rate to 85 Hz to run the game, which eliminates flicker. However, this does not work on all monitors, and not at all on flat panel displays, which is why it is disabled by default.
The "Force alternate letterbox resolution" option is only available for 320x200 and 640x400 modes, and tells AGS to actually run at 320x240 or 640x480 instead, with black 'letterbox' borders at the top and bottom of the screen. This is useful because some computers no longer support the 320x200 or 640x400 resolutions, but do support the letterboxed versions.
"Smooth scaled sprites" will apply anti-aliasing to scaled characters, in order to give a smoother look to the resizing. This can slow down the game though, so it is off by default.
Finally, the "Downgrade 32-bit graphics to 16-bit" option is only available for 32-bit games. It allows people with slower PCs to choose to play the game at 16-bit instead, in order to boost performance. If they use this, the graphical quality will reduce, but it should at least allow them to play the game at a decent speed.
