hi, im writing a software rasterizer, and it works fine in wireframe mode and with filled polygons. but i have problems with perspective correct interpolation of the z-value and texture coordinates. i transform vertices with modelview and porjection matrix, and then divide all values of the resulting vector by W. but now in the scanline-renderer i must interpolate the z-values, texture-coordinates etc over the polygon. i cant figure out how EXACTLY this works. i found some ressources on this topic, but i dont know what the variables in those formulas mean.(z0,z1,f,z,w... yes...) basically i have 3 points given with its screen-coordinates and texture coords and z-value. then for each scanline i must compute the perspective correct interpolated values... how? thanks for answers.

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