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Thanks and a question/suggestion

From: Georg Rehfeld (
Date: Sun 10 Nov 2002 - 06:58:05 GMT

  • Next message: Tony Cook: "Re: Thanks and a question/suggestion"

    Hi Imager developers,

    I'm new to this list, so please let me introduce myself:

    - occasional perl user/developer since ~ 10 years
    - OO using Java (and perl) since 4 years and in the future

    Thanks to all Imager developers for giving it to me and the world!
    Nice work and MUCH better than GD. It's near to replace photoshop/
    gimp when it comes to batch/programmed jobs. Hey, I really like it!

    Note, that I'm just a USER of Imager, don't expect me to have the
    neccessary knowledge to enhance it, I can only ask for/suggest
    features (currently).

    My actual fun-project using Imager is sort of a plot and, though
    I have several other ways to proceed, I'm missing one feature in
    Imager, that photoshop and gimp have (and GD incorrectly claims to
    have): drawing with a brush.

    You all know, what photoshop/gimp can do with brushes: draw
    points, lines, polylines using a little image, typically more
    opaque in the center and transparent in the outer regions. The brush
    is grayscale with transparency. The essential point is: along a
    line the brush image is not stupidly used pixel for pixel to
    overdraw, what is in the image already, as with GD. Instead the
    outer regions along the line have the brush transparency preserved
    so that a nice antialiased line is drawn over the image.

    The stupid GD approach (draw the first pixel of the line with the
    brush, then draw the next pixel over what GD just had drawn ...)
    ends up in a nearly opaque line, regardless of the transparency
    of brush pixels.

    Remember, I'm NOT an expert at all, but I believe, one way to go

    - have a temporary grayscale buffer for the line to draw,
      initialized to all transparent
    - draw the brush pixels only there, where the buffer is more
      transparent or more light
    - copy the buffer onto the image with transparency (rubthrough)
      and in the requested foreground color

    Do you have a plan to add brush drawing? If not, is there any taker
    (sorry, I WOULD be a taker, but I CAN'T)? A new 'brush=>$brush_img'
    parameter would be neccessary in several places.


     ___ ___
    | + | |__ Georg Rehfeld Woltmanstr. 12 20097 Hamburg
    |_|_\ |___ 06124@xyz.molar.is +49 (40) 23 53 27 10

    PS: The fun project (a fancy year calendar with HTML map support
        in pre-alpha state) to be contributed to the Imager project,
        when it's some day beta or better.