Unit 'agraphics' Package
[Overview][Constants][Types][Procedures and functions][Variables][Index] [#os4units]

ScrollVPort

Reinterpret RasInfo information in ViewPort to reflect the current Offset values.

Declaration

Source position: agraphics.pas line 2391

procedure ScrollVPort(

  Vp: PViewPort

);

Arguments

Vp

  

A pointer to a ViewPort structure that is currently be displayed.

Description

After the programmer has adjusted the Offset values in the RasInfo structures of ViewPort, change the the copper lists to reflect the the Scroll positions. Changing the BitMap ptr in RasInfo and not changing the the Offsets will effect a double buffering affect.

Errors

Amiga video drivers can perform a validation of offsets, and may refuse to scroll the screen too far (if they somehow can't provide the requested offset). In this case offset values in the ViewPort will be updated in order to reflect the real result of the operation.


Documentation generated on: 2021-07-30