- Altering the Screen Environment -

The screen setup routines in the libraries seem to contain a significant bug.
Setting the screen resolution with GsInitGraph does not always have the desired effect.

- Original information contributed by Alex Herbert to the SCEE 2D graphics newsgroup -

In order to have the screen display functioning correctly, you must alter the display environment variable... 

extern DISPENV GsDISPENV;   // To be declared globally
Whenever you want to setup or alter the graphics display environment in your functions, you should alter this variable such... 
GsInitGraph(320, 256, ...);
GsDISPENV.screen.w = 320;
GsDISPENV.screen.h = 256;  // Height can now be properly set to full PAL screen
It is worth noting that the screen width and height can be set to any sensible value - it is not necessary to conform to the standard screen sizes listed in the User Guide.
Furthermore, the screen position may be shifted by altering the environment variable... 
GsDISPENV.screen.x = ?;  // These values set the screen offset position
GsDISPENV.screen.y = ?;

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