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3.8.2 Texture Magnification


When indicates magnification, the value assigned to TEXTURE_MAG_FILTER determines how the texture value is obtained. There are two possible values for TEXTURE_MAG_FILTER: NEAREST and LINEAR. NEAREST behaves exactly as NEAREST for TEXTURE_MIN_FILTER (equation 3.13 and 3.14 are used); LINEAR behaves exactly as LINEAR for TEXTURE_MIN_FILTER (equation 3.15 is used). The level-of-detail 0 texture array is always used for magnification.

Finally, there is the choice of c, the minification vs. magnification switch-over point. If the magnification filter is given by LINEAR and the minification filter is given by NEAREST_MIPMAP_NEAREST or NEAREST_MIPMAP_LINEAR, then . This is done to ensure that a minified texture does not appear ``sharper'' than a magnified texture. Otherwise c = 0.

David Blythe
Sat Mar 29 02:23:21 PST 1997