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  1. FOP
  2. FOP-1650

[PATCH] Proposed correction for resolution handling

Details

    • Bug
    • Status: Closed
    • Resolution: Fixed
    • 2.5
    • None
    • fo/unqualified
    • Operating System: All
      Platform: All
    • 47027

    Description

      Hi Andreas,

      in your revision http://svn.apache.org/viewvc?rev=764317&view=rev you intended to fix the conversion from pixels to internal millipoints. I'm afraid you seem to have misunderstood the intention of the source and target resolution. When I introduced the two resolutions the intention was that the source resolution specifies the resolution at which pixel lengths are interpreted on the source side (pixel lengths in FO, pixel lengths for bitmaps that don't have resolution information etc.). The target resolution OTOH specifies the resolution at which the output device operates. For example, if you target a 300 dpi printer, you specify 300 dpis. For the screen you'd specify 96 dpi (most probably). This value controls the number of pixels generated for a bitmap that is generated from a vector graphic image that is rendered to a pixel-based output format (like PCL or PNG).

      FO src res layout engine. tgt res Output
      <px> -------> <mpt> -------> <px>

      The attached patch demonstrates how I would fix this. An example of the result: Specify a table column with 72px and you get 72000mpt as before at default settings (72dpi). At a higher resolution, the pixels get smaller as you have more pixels per inch. So at 144dpi, you have twice as many pixels in the same space per dimension. The pixel length is half the previous length. 72px are now 36000mpt.

      Attachments

        1. b47027.diff
          12 kB
          Andreas L. Delmelle
        2. b47027.diff
          9 kB
          Andreas L. Delmelle
        3. SourceResolutionPatch.diff
          6 kB
          Jeremias Maerki

        Activity

          Attachment SourceResolutionPatch.diff has been added with description: my proposed patch

          jeremias@apache.org Jeremias Maerki added a comment - Attachment SourceResolutionPatch.diff has been added with description: my proposed patch

          OK, indeed seems I misunderstood the intentions.

          Patch looks fine to me (as far as I understand... my using the 'magic number' 72.0f should definitely be abandoned)

          adelmelle@apache.org Andreas L. Delmelle added a comment - OK, indeed seems I misunderstood the intentions. Patch looks fine to me (as far as I understand... my using the 'magic number' 72.0f should definitely be abandoned)

          Just wanted to go ahead and commit the changes, then noticed I had made an additional change to FOTreeTester and ResultCollector a while back, which I'd like to post for review first.

          The one difference is that I made the distinction between a fatal error that arises during parsing, and a failed assertion in a test that was successfully parsed. If this makes sense, I'll commit the attached patch later this weekend (or early next week).

          adelmelle@apache.org Andreas L. Delmelle added a comment - Just wanted to go ahead and commit the changes, then noticed I had made an additional change to FOTreeTester and ResultCollector a while back, which I'd like to post for review first. The one difference is that I made the distinction between a fatal error that arises during parsing, and a failed assertion in a test that was successfully parsed. If this makes sense, I'll commit the attached patch later this weekend (or early next week).

          Attachment b47027.diff has been added with description: same patch, but including another change in FOTreeTester

          adelmelle@apache.org Andreas L. Delmelle added a comment - Attachment b47027.diff has been added with description: same patch, but including another change in FOTreeTester

          Forgot to include the affected AssertElement.java in the previous attachment

          adelmelle@apache.org Andreas L. Delmelle added a comment - Forgot to include the affected AssertElement.java in the previous attachment

          Attachment b47027.diff has been added with description: correction: added missing file

          adelmelle@apache.org Andreas L. Delmelle added a comment - Attachment b47027.diff has been added with description: correction: added missing file

          No feedback in the meantime, so I've committed the changes: see r766492

          Thanks for the feedback!

          adelmelle@apache.org Andreas L. Delmelle added a comment - No feedback in the meantime, so I've committed the changes: see r766492 Thanks for the feedback!
          gadams Glenn Adams added a comment -

          batch transition pre-FOP1.0 resolved+fixed bugs to closed+fixed

          gadams Glenn Adams added a comment - batch transition pre-FOP1.0 resolved+fixed bugs to closed+fixed

          People

            fop-dev@xmlgraphics.apache.org fop-dev
            jeremias@apache.org Jeremias Maerki
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            Dates

              Created:
              Updated:
              Resolved: