44 lines
1.5 KiB
C++
44 lines
1.5 KiB
C++
///////////////////////////////////////////////////////////////////////////////////////////////////
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// OpenGL Mathematics Copyright (c) 2005 - 2012 G-Truc Creation (www.g-truc.net)
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///////////////////////////////////////////////////////////////////////////////////////////////////
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// Created : 2009-03-06
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// Updated : 2009-03-09
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// Licence : This source is under MIT License
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// File : glm/gtx/gradient_paint.inl
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///////////////////////////////////////////////////////////////////////////////////////////////////
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namespace glm
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{
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template <typename valType>
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valType radialGradient
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(
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detail::tvec2<valType> const & Center,
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valType const & Radius,
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detail::tvec2<valType> const & Focal,
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detail::tvec2<valType> const & Position
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)
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{
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detail::tvec2<valType> F = Focal - Center;
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detail::tvec2<valType> D = Position - Focal;
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valType Radius2 = pow2(Radius);
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valType Fx2 = pow2(F.x);
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valType Fy2 = pow2(F.y);
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valType Numerator = (D.x * F.x + D.y * F.y) + sqrt(Radius2 * (pow2(D.x) + pow2(D.y)) - pow2(D.x * F.y - D.y * F.x));
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valType Denominator = Radius2 - (Fx2 + Fy2);
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return Numerator / Denominator;
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}
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template <typename valType>
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valType linearGradient
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(
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detail::tvec2<valType> const & Point0,
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detail::tvec2<valType> const & Point1,
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detail::tvec2<valType> const & Position
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)
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{
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detail::tvec2<valType> Dist = Point1 - Point0;
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return (Dist.x * (Position.x - Point0.x) + Dist.y * (Position.y - Point0.y)) / glm::dot(Dist, Dist);
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}
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}//namespace glm
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