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Thread: Lesson 9 : Bitmaps and Animation

  1. #1
    Intern Contributor
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    Jan 2002
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    Lesson 9 : Bitmaps and Animation

    This may be a little off topic...

    I have been following the NeHe tutorials for a couple days now, and have a problem with lesson 9.

    The program compiles and runs fine, but I can always see the full quad on screen, and not the bitmap image (it therefore looks nothing like a star). I have been using paintbrush to create the bitmaps, and I think this is the problem because when I used a bitmap from a game the problem disappeared.

    Is this a problem with the bitmaps I have created and if so, how can it be corrected?

    PS I also have photoshop, with no knowledge of how to use it - anyone know any good online tutorials for it?

  2. #2
    Junior Member Regular Contributor
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    Re: Lesson 9 : Bitmaps and Animation

    Perhaps you have drawn a 16 or 256 color bitmap. As I see it you need a 16 million color bitmap (24bit). You can load your own pic into photoshop and transform it to 24bits. I have only the german version, but its the third menu from left (Picture or so), the first enty (Mode?) and there the two enties 'RGB-Color' and '8 bit per channel' have to be checked. Then save the image and try again.

    Marc

  3. #3
    Intern Contributor
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    Re: Lesson 9 : Bitmaps and Animation

    sorry, I did as you suggested to no avail. I can still see the whole quad.

    BTW, the image is a simple black circle on a white background, 64 x 64, if its of any relevance

  4. #4
    Senior Member OpenGL Pro
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    Re: Lesson 9 : Bitmaps and Animation

    I believe Nehe's demo uses a blending mode, so that the black parts of the texture dont show up.

    If the edge of your texture is white, then it will show up just like it does. What you want to do, is make all of your image black apart from the parts you want to see.

    Or something like that.

  5. #5
    Intern Contributor
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    Re: Lesson 9 : Bitmaps and Animation

    That works, or it is roughly what I expected - innit pretty!!

    Many Thanks

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