Screen Functions

Statements and procedures that work with the graphics display.

Description
   These statements and procedures control the graphics capabilities of the 
   FreeBASIC graphics library. Screen modes can be set with varying 
   resolutions and color depths, window events can be handled, and specific 
   OpenGL procedures can be retrieved.

Working with screen modes
   Procedures for setting and retrieving information about screen modes.
Working with pages
   Procedures that manipulate screen pages.
Working video memory
   Procedures that provide direct access to framebuffer memory.
Screen Metrics
   Procedures that control the way coordinates are interpreted.
Screen Data Types
   Data types and data definitions for screen functions.

Working with screen modes
   ScreenList
      Gets the available fullscreen resolutions.
   Screen and ScreenRes
      Sets a new graphics display mode.
   ScreenInfo
      Gets information about the system desktop or current display mode.
   ScreenControl
      Gets or sets internal graphics library settings.
   ScreenEvent
      Gets system events.
   ScreenGLProc
      Returns the address of an OpenGL procedure.
   WindowTitle
      Sets the running program's window caption.

Working with pages
   Cls
      Clears the entire screen or viewport.
   ScreenSet
      Sets the current work and visible pages.
   ScreenCopy and PCopy and Flip
      Copies pixel data from one page to another.
   ScreenSync
      Waits for the vertical refresh of the monitor.
Working video memory
   ScreenPtr
      Gets the address of the working page's framebuffer.
   ScreenLock
      Locks the current working page's framebuffer for direct access.
   ScreenUnlock
      Reverts a previous ScreenLock command.

Screen Metrics
   View (Graphics)
      Sets a clipping region for all drawing and blitting procedures.
   Window
      Sets a new coordinate mapping for the current viewport.
   PMap
      Converts coordinates between physical and view mappings.
   PointCoord
      Queries Draw's pen position.

Screen Data Types
   Event
      Data type for ScreenEvent function.

