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  1. JDK
  2. JDK-4106598

AWT clipping performance on Windows can be significantly improved

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    • Subcomponent:
    • Resolved In Build:
      1.1.6
    • CPU:
      x86
    • OS:
      windows_nt
    • Verification:
      Verified

      Description

      The ReleaseDC() method in AwtGraphics contains a redundant call to LogicalSelectClipRgn.

      This comment is extracted from an email message received from the actual submitter of this bug report, Armin Ebrahimi <###@###.###>:
      "It is not necessary to reset the clip region to NULL since each thread calls either GetDC or ValidateDC which in turn sets the clipping region. Removing
      this call provides for a substantial improvement when clipping is enabled."

      Armin has measured a performance improvement of up to 50% for clipped AWT calls (e.g., draw line, rectangle, and oval drawing, etc).

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            Assignee:
            cchongsunw Creighton Chong (Inactive)
            Reporter:
            cchongsunw Creighton Chong (Inactive)
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