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hoshi55
06-13-2001, 04:25 AM
i'm a bit confused by a positional light source... i tarnsform my whole modelview matrix with the inverse camera transformations, then draw lots off objects/stuff, which works fine.
in addition to the directioanl source that lights the scene, ive also included a positional with fixed coords. however, the light source never seems to be at the right place, although its positin is transformed by the matrix stack. i know that the x,y,z coords of a directional source are always multiplied by -1, but for a positional??
one more problem, light attenuation does not seem to work correctly. looking at the attenuation formula, i suppose that a factor of about 2.0 for linear attenuation should be ok to create a light that fades quite soon if distance increases, but the intensity always stays the same no no matter how tall my attenuation factor is.