glm/glm/gtc/glu_replacement.inl
2010-11-12 14:24:28 +00:00

123 lines
3.6 KiB
C++

///////////////////////////////////////////////////////////////////////////////////////////////////
// OpenGL Mathematics Copyright (c) 2005 - 2010 G-Truc Creation (www.g-truc.net)
///////////////////////////////////////////////////////////////////////////////////////////////////
// Created : 2010-11-12
// Updated : 2010-11-12
// Licence : This source is under MIT License
// File : glm/gtc/glu_replacement.inl
///////////////////////////////////////////////////////////////////////////////////////////////////
namespace glm{
namespace gtc{
namespace glu_replacement
{
template <typename valType>
inline detail::tmat4x4<valType> ortho(
valType const & left,
valType const & right,
valType const & bottom,
valType const & top)
{
detail::tmat4x4<valType> Result(1);
Result[0][0] = valType(2) / (right - left);
Result[1][1] = valType(2) / (top - bottom);
Result[2][2] = - valType(1);
Result[3][0] = - (right + left) / (right - left);
Result[3][1] = - (top + bottom) / (top - bottom);
return Result;
}
template <typename valType>
inline detail::tmat4x4<valType> perspective(
valType const & fovy,
valType const & aspect,
valType const & zNear,
valType const & zFar)
{
valType range = tan(radians(fovy / valType(2))) * zNear;
valType left = -range * aspect;
valType right = range * aspect;
valType bottom = -range;
valType top = range;
detail::tmat4x4<valType> Result(valType(0));
Result[0][0] = (valType(2) * zNear) / (right - left);
Result[1][1] = (valType(2) * zNear) / (top - bottom);
Result[2][2] = - (zFar + zNear) / (zFar - zNear);
Result[2][3] = - valType(1);
Result[3][2] = - (valType(2) * zFar * zNear) / (zFar - zNear);
return Result;
}
template <typename T, typename U>
inline detail::tvec3<T> project(
detail::tvec3<T> const & obj,
detail::tmat4x4<T> const & model,
detail::tmat4x4<T> const & proj,
detail::tvec4<U> const & viewport)
{
detail::tvec4<T> tmp = detail::tvec4<T>(obj, T(1));
tmp = model * tmp;
tmp = proj * tmp;
tmp /= tmp.w;
tmp = tmp * T(0.5) + T(0.5);
tmp[0] = tmp[0] * T(viewport[2]) + T(viewport[0]);
tmp[1] = tmp[1] * T(viewport[3]) + T(viewport[1]);
return detail::tvec3<T>(tmp);
}
template <typename T, typename U>
inline detail::tvec3<T> unProject(
detail::tvec3<T> const & win,
detail::tmat4x4<T> const & model,
detail::tmat4x4<T> const & proj,
detail::tvec4<U> const & viewport)
{
detail::tmat4x4<T> inverse = glm::inverse(proj * model);
detail::tvec4<T> tmp = detail::tvec4<T>(win, T(1));
tmp.x = (tmp.x - T(viewport[0])) / T(viewport[2]);
tmp.y = (tmp.y - T(viewport[1])) / T(viewport[3]);
tmp = tmp * T(2) - T(1);
detail::tvec4<T> obj = inverse * tmp;
obj /= obj.w;
return detail::tvec3<T>(obj);
}
template <typename T>
inline detail::tmat4x4<T> lookAt(
const detail::tvec3<T>& eye,
const detail::tvec3<T>& center,
const detail::tvec3<T>& up)
{
detail::tvec3<T> f = normalize(center - eye);
detail::tvec3<T> u = normalize(up);
detail::tvec3<T> s = normalize(cross(f, u));
u = cross(s, f);
detail::tmat4x4<T> Result(1);
Result[0][0] = s.x;
Result[1][0] = s.y;
Result[2][0] = s.z;
Result[0][1] = u.x;
Result[1][1] = u.y;
Result[2][1] = u.z;
Result[0][2] =-f.x;
Result[1][2] =-f.y;
Result[2][2] =-f.z;
/* Test this instead of translate3D
Result[3][0] =-dot(s, eye);
Result[3][1] =-dot(y, eye);
Result[3][2] = dot(f, eye);
*/
return gtc::matrix_transform::translate(Result, -eye);
}
}//namespace glu_replacement
}//namespace gtc
}//namespace glm