DOCUMENT:Q28344  06-NOV-1999  [win16sdk]
TITLE   :PRB: PlayMetaFile() Not as Fast as More Complex Technique
PRODUCT :Microsoft Windows Software Development Kit
PROD/VER:WINDOWS:3.0,3.1
OPER/SYS:
KEYWORDS:kb16bitonly

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The information in this article applies to:

 - Microsoft Windows Software Development Kit (SDK) versions 3.0, 3.1 
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SYMPTOMS
========

The PlayMetaFile() function is slower than using a loop that contains the
EnumMetaFile() and PlayMetaFileRecord() commands.

CAUSE
=====

PlayMetaFile() takes longer because it plays the metafile records, and it also
performs several additional steps:

1. Verifies that its handle parameter points to a valid metafile.

2. Locks the metafile.

3. Saves all objects in the device context (pens, brushes, regions, etc.).

4. Plays the metafile records.

5. Restores all objects in the display context. PlayMetaFile() will restore
   default objects if other restoration fails.

6. Unlocks the metafiles.

7. Deletes all objects created while playing the metafile.

To achieve this speed advantage, the callback function specified in
EnumMetaFile() would call only PlayMetaFileRecord(). The actual speed of
execution is determined by the amount of processing done in the EnumMetaFile()
callback function.

Additional query words: 3.00 3.10 no32bit

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Keywords          : kb16bitonly 
Technology        : kbAudDeveloper kbWin3xSearch kbSDKSearch kbWinSDKSearch kbWinSDK300 kbWinSDK310
Version           : WINDOWS:3.0,3.1

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