Mantis - Croquet
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1684 Any minor always 08-16-05 02:38 08-20-05 03:27
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0001684: GLByte color components are in range 0-127, not 0-255
When drawing points (and presumably other GL primitives)
with glDrawArrays (and presumably other methods)
with color components of type GLByte,
the color space seems to be the range 0-127, not 0-255.

Values of 127 are full, values of 128 and above are transformed to zero.

So when you would expect grey from 127, 127, 127, you get white,
and when you would expect the same grey but with a tiny bit of yellow added from 128, 128, 127, you get solid blue.

See screenshot below and attached TPrimitive subclass which demonstrate. [^] [^] (1,650 bytes) 08-16-05 02:38

08-20-05 03:26   
The range of GLByte is -128 to 127. This is not a bug. Read the OpenGL Spec. You'll also find GLUnsignedByte there with a range of 0 to 255.