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Thread: why glLogicOp no use RGBA?

  1. #1
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    why glLogicOp no use RGBA?

    "Logical pixel operations are not applied to RGBA color buffers."

    Is mean only use color index?
    opengl driver applied to RGBA glLogicOp difficult?or will give rise to miss?

  2. #2
    Senior Member OpenGL Pro sqrt[-1]'s Avatar
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    Re: why glLogicOp no use RGBA?

    You must be looking at an old spec. By at least OpenGL 1.2 logic ops were allowed on RGBA frame buffers.

  3. #3
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    Re: why glLogicOp no use RGBA?

    Originally posted by sqrt[-1]:
    You must be looking at an old spec. By at least OpenGL 1.2 logic ops were allowed on RGBA frame buffers.
    I look at msdn and red book of opengl 1.2

    I know msdn is older.but red book...is my miss?

  4. #4
    Senior Member OpenGL Pro sqrt[-1]'s Avatar
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    Re: why glLogicOp no use RGBA?

    It is in the blue book 1.2 and the red book 1.2

    Look for GL_COLOR_LOGIC_OP on google and if you are using the red book 1.2 look on page 449.

    You just need to do glEnable(GL_COLOR_LOGIC_OP);

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