Metafile Restrictions

The following restrictions apply to the generation of all metafiles, and also to the generation of a PM_Q_STD print file to a device:

• If GpiWCBitBlt or GpiBitBlt is used to copy a bit map to a device context in an application, the application should not delete that bit map handle with GpiDeleteBitmap before the device context is closed (metafile is closed).

• GpiSetPS must not be used.

• GpiSetPageViewport is ignored.

The following section lists some general rules that must be followed when creating a metafile that is to be acceptable to SAA-conforming implementations, or replayed into a presentation space that is in draw-and-retain or retain mode (see "GpiSetDrawingMode" in Graphics Programming Interface Programming Reference).

• These items must be established or defaulted before any drawing occurs to the graphics presentation space, and not changed subsequently:

  • The graphics field (GpiSetGraphicsField). For an SAA-conforming metafile, the graphics field must be defaulted or set to no clipping. -
    The code page for the default character set (GpiSetCp).
    -
    The color table or palette (GpiCreateLogColorTable or GpiCreatePalette). The size of the color table must not exceed 31KB (KB equals 1024 bytes).
    -
    The default viewing transform (GpiSetDefaultViewMatrix).
    -
    The setting of the draw controls (GpiSetDrawControl). DCTL_DISPLAY must be defaulted or set ON.
    -
    The default values of attributes (see "GpiSetDefAttrs" in the Graphics Programming Interface Programming Reference), viewing limits (see "GpiSetDefViewingLimits" in the Graphics Programming Interface Programming Reference), primitive tag (see "GpiSetDefTag" in the Graphics Programming Interface Programming Reference) and arc parameters (see "GpiSetDefArcParams" in the Graphics Programming Interface Programming Reference).
    
    These calls should not be used:

    • GpiBitBlt -
      GpiDeleteSetId (note that this means that local identifiers cannot be used again within the picture)
      -
      GpiErase
      -
      GpiExcludeClipRectangle
      -
      GpiIntersectClipRectangle
      -
      GpiOffsetClipRegion
      -
      GpiPaintRegion
      -
      GpiResetPS
      -
      GpiSetClipRegion
      -
      GpiSetPel
      -
      GpiSetPS
      -
      DevEscape (for an escape which is metafiled).
      
      GpiCreateLogFont must not redefine a local identifier that has previously been used within the picture.
      
      The metafile context must not be reassociated.
      
      If a bit map is used as the source of a GpiWCBitBlt operation, or as an area-fill pattern, it must not be modified or deleted (GpiDeleteBitmap) before the metafile is closed.
      
      Only these foreground mixes must be used (see "GpiSetMix" in the Graphics Programming Interface Programming Reference):

      • FM_DEFAULT -
        FM_OR
        -
        FM_OVERPAINT
        -
        FM_LEAVEALONE
        
        Only these background mixes must be used (see "GpiSetBackMix" in the Graphics Programming Interface Programming Reference):

        • BM_DEFAULT -
          BM_OVERPAINT
          -
          BM_LEAVEALONE
          
          If palettes are used (see "GpiCreatePalette" in the Graphics Programming Interface Programming Reference): the palette that is metafiled is the one in force when the metafile device context is dissociated from the (final) presentation space. If the palette is changed during the course of the picture (using GpiSetPaletteEntries), it must therefore only be with incremental additions.

          Note: There is no restriction concerning the use of primitives outside segments. These are metafiled in segment(s) with zero identifier.

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