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My-Little-Forum / mylittleforum

A simple PHP and MySQL based internet forum that displays the messages in classical threaded view (tree structure)
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Fix failing imagerotate with 180° rotation (rare corner case) #668

Closed auge8472 closed 1 year ago

auge8472 commented 1 year ago

As reported in the project forum and documented in issue #658 it is possible, that the function imagerotate does not work with the rotation angle of exactly 180° in very rare cases. Leaving aside the fact that the concept of captchas is absolutely out of date and thinking about the current solution in modules/captcha/captcha.php it is …

  1. … IMHO not ideal to rely on a chance of 0 or 1 to try to rotate the image or not and …
  2. … to rotate the background exclusively with an angle of 180° or not (0°)

Thatswhy I replaced the rotation (with imagerotate) with a mirroring with the function imageflip, which provides three modes (horizontal, vertical and both at once) to generate the resulting image. The new solution decides if to rotate or not with a random number in the range from 0 to 5 and the criterion of the number being even or odd. The mode of the mirroring is set with a further random number in the range from 0 to 2, that selects the mode to use from an array. See therefor 972e6da9dbf4a3e3cb49fc2844bd311909a9f0ba.

Furthermore I reformatted the files modules/captcha/captcha.php and modules/captcha/captcha_image.php. See therefor de7923c31cbd5774567516573b6feb3cb9d336d3 and 1e9d98c5d6c54e8c4752178b010216c8bca1160f

auge8472 commented 1 year ago

@loesler

vihuna stated this to be successfully tested in a comment in issue #658 but with protecting the base branch of the repository here in Github, a review is mandatory.

loesler commented 1 year ago

... with protecting the base branch of the repository here in Github, a review is mandatory.

Just a general remark: I can understand this option but I already have little time to help so I do not want to use these small time frames for reviewing code.

auge8472 commented 1 year ago

I can understand this option but I already have little time to help so I do not want to use these small time frames for reviewing code.

I can fully understand you. I will check, if I can change the configuration in a apprpriate manner.