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Our method forms identical tangent directions at the interpolated data points of the piecewise cubic spline by replacing each cubic piece with a pair of quadratic pieces. The resulting representation can lead to substantial performance improvements for rendering geometrically complex spline models like hair and fiber-level cloth. Such models are typically represented using cubic splines that are C1-continuous, a property that is preserved with our degree reduction. Therefore, our method can also be considered a new quadratic curve construction approach for high-performance rendering. We prove that it is possible to construct a pair of quadratic curves with C1 continuity that passes through any desired point on the input cubic curve. Moreover, we prove that when the pair of quadratic pieces corresponding to a cubic piece have equal parametric lengths, they join exactly at the parametric center of the cubic piece, and the deviation in positions due to degree reduction is minimized.<\/jats:p>","DOI":"10.1145\/3406178","type":"journal-article","created":{"date-parts":[[2021,3,23]],"date-time":"2021-03-23T17:45:26Z","timestamp":1616521526000},"page":"1-17","update-policy":"https:\/\/doi.org\/10.1145\/crossmark-policy","source":"Crossref","is-referenced-by-count":6,"title":["Quadratic Approximation of Cubic Curves"],"prefix":"10.1145","volume":"3","author":[{"given":"Nghia","family":"Truong","sequence":"first","affiliation":[{"name":"University of Utah"}]},{"given":"Cem","family":"Yuksel","sequence":"additional","affiliation":[{"name":"University of Utah"}]},{"given":"Larry","family":"Seiler","sequence":"additional","affiliation":[{"name":"Facebook Reality Labs"}]}],"member":"320","published-online":{"date-parts":[[2020,8,26]]},"reference":[{"key":"e_1_2_2_1_1","unstructured":"Jens Alfke. 1994. 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