spacebox/lib/glm/gtx/gradient_paint.inl

37 lines
904 B
C++

/// @ref gtx_gradient_paint
namespace glm
{
template<typename T, qualifier Q>
GLM_FUNC_QUALIFIER T radialGradient
(
vec<2, T, Q> const& Center,
T const& Radius,
vec<2, T, Q> const& Focal,
vec<2, T, Q> const& Position
)
{
vec<2, T, Q> F = Focal - Center;
vec<2, T, Q> D = Position - Focal;
T Radius2 = pow2(Radius);
T Fx2 = pow2(F.x);
T Fy2 = pow2(F.y);
T 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));
T Denominator = Radius2 - (Fx2 + Fy2);
return Numerator / Denominator;
}
template<typename T, qualifier Q>
GLM_FUNC_QUALIFIER T linearGradient
(
vec<2, T, Q> const& Point0,
vec<2, T, Q> const& Point1,
vec<2, T, Q> const& Position
)
{
vec<2, T, Q> Dist = Point1 - Point0;
return (Dist.x * (Position.x - Point0.x) + Dist.y * (Position.y - Point0.y)) / glm::dot(Dist, Dist);
}
}//namespace glm