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Thread: Rotation along the Y-axis

  1. #1
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    Post Rotation along the Y-axis

    Overview of program, to understand Question
    I'm loading an image in type QImage
    Then I paint the image in label,
    & allow user to make markings on image (draw point/ellipse/...)
    After the user finish editing the image
    All the points the user created via mouse clicks is stored in an array.

    Later in the program I'm rotating image along the y-axis then repainting the image.
    but when I paint all the points that were stored in array its not being rotated accordingly(naturally)

    The rotation of image along the y-axis.... Works
    How do I rotate the points along the same axis so its inline with image


    ie(creating a perspective look on output)

    code to transform image
    Qt Code:
    1. //before paint function
    2. QTransform pptv;
    3. pptv.rotate(-60, Qt::YAxis);
    4. image1 = image1.transformed(pptv);
    5. imageDrawFlag1 = true;
    To copy to clipboard, switch view to plain text mode 
    & i paint the transformed image
    but when it comes to repainting the points
    Qt Code:
    1. //In paint function
    2. foreach(tempPoint, markers)
    3. {
    4. painter.drawEllipse(tempPoint, 5, 5);
    5. }
    6. //painter.rotate -> only allows an integer, Does not allow which axis
    To copy to clipboard, switch view to plain text mode 

    How would I go about solving this issue?

    Kind Regards

    Having some network issues today, my posts or responses might be delayed

  2. #2
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    Default Re: Rotation along the Y-axis

    can you save all of your paintings in another image, and rotate that image?

  3. #3
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    Default Re: Rotation along the Y-axis

    What happens if you call QPainter::setTransform() with the same transform?

  4. The following user says thank you to ChrisW67 for this useful post:

    2lights (16th August 2013)

  5. #4
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    Default Re: Rotation along the Y-axis

    QPainter::setTransform() with the same transform... Works

    Thanks

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