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Tracing Ray Differentials. Homan Igehy Speaker: Haoji. Ray tracing ray differentials derivatives of the ray with respect to image space coordinates, by applying the derivatives of the functions. Initial value. Transfer. Reflection.
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Tracing Ray Differentials Homan Igehy Speaker: Haoji
Ray tracing • ray differentials • derivatives of the ray with respect to image space coordinates, by applying the derivatives of the functions.
If we know the formula for how a ray is affected by a phenomenon, then we can differentiate it to get a formula for how a ray differential is affected without any understanding of the phenomenon
Texture Filtering • If we can approximate the difference between the texture coordinates corresponding to a ray and its neighboring rays, then we can find the size and shape of a filtering kernel in texture space. pixel’s footprint in texture space based on the pixel-to-pixel spacing:
Given this parallelogram, one of several texture filtering methods can be used • mip mapping • level-of-dital =>