/// @ref gtx_intersect | |
/// @file glm/gtx/intersect.inl | |
namespace glm | |
{ | |
template <typename genType> | |
GLM_FUNC_QUALIFIER bool intersectRayPlane | |
( | |
genType const & orig, genType const & dir, | |
genType const & planeOrig, genType const & planeNormal, | |
typename genType::value_type & intersectionDistance | |
) | |
{ | |
typename genType::value_type d = glm::dot(dir, planeNormal); | |
typename genType::value_type Epsilon = std::numeric_limits<typename genType::value_type>::epsilon(); | |
if(d < -Epsilon) | |
{ | |
intersectionDistance = glm::dot(planeOrig - orig, planeNormal) / d; | |
return true; | |
} | |
return false; | |
} | |
template <typename genType> | |
GLM_FUNC_QUALIFIER bool intersectRayTriangle | |
( | |
genType const & orig, genType const & dir, | |
genType const & v0, genType const & v1, genType const & v2, | |
genType & baryPosition | |
) | |
{ | |
genType e1 = v1 - v0; | |
genType e2 = v2 - v0; | |
genType p = glm::cross(dir, e2); | |
typename genType::value_type a = glm::dot(e1, p); | |
typename genType::value_type Epsilon = std::numeric_limits<typename genType::value_type>::epsilon(); | |
if(a < Epsilon && a > -Epsilon) | |
return false; | |
typename genType::value_type f = typename genType::value_type(1.0f) / a; | |
genType s = orig - v0; | |
baryPosition.x = f * glm::dot(s, p); | |
if(baryPosition.x < typename genType::value_type(0.0f)) | |
return false; | |
if(baryPosition.x > typename genType::value_type(1.0f)) | |
return false; | |
genType q = glm::cross(s, e1); | |
baryPosition.y = f * glm::dot(dir, q); | |
if(baryPosition.y < typename genType::value_type(0.0f)) | |
return false; | |
if(baryPosition.y + baryPosition.x > typename genType::value_type(1.0f)) | |
return false; | |
baryPosition.z = f * glm::dot(e2, q); | |
return baryPosition.z >= typename genType::value_type(0.0f); | |
} | |
template <typename genType> | |
GLM_FUNC_QUALIFIER bool intersectLineTriangle | |
( | |
genType const & orig, genType const & dir, | |
genType const & vert0, genType const & vert1, genType const & vert2, | |
genType & position | |
) | |
{ | |
typename genType::value_type Epsilon = std::numeric_limits<typename genType::value_type>::epsilon(); | |
genType edge1 = vert1 - vert0; | |
genType edge2 = vert2 - vert0; | |
genType pvec = cross(dir, edge2); | |
float det = dot(edge1, pvec); | |
if (det > -Epsilon && det < Epsilon) | |
return false; | |
float inv_det = typename genType::value_type(1) / det; | |
genType tvec = orig - vert0; | |
position.y = dot(tvec, pvec) * inv_det; | |
if (position.y < typename genType::value_type(0) || position.y > typename genType::value_type(1)) | |
return false; | |
genType qvec = cross(tvec, edge1); | |
position.z = dot(dir, qvec) * inv_det; | |
if (position.z < typename genType::value_type(0) || position.y + position.z > typename genType::value_type(1)) | |
return false; | |
position.x = dot(edge2, qvec) * inv_det; | |
return true; | |
} | |
template <typename genType> | |
GLM_FUNC_QUALIFIER bool intersectRaySphere | |
( | |
genType const & rayStarting, genType const & rayNormalizedDirection, | |
genType const & sphereCenter, const typename genType::value_type sphereRadiusSquered, | |
typename genType::value_type & intersectionDistance | |
) | |
{ | |
typename genType::value_type Epsilon = std::numeric_limits<typename genType::value_type>::epsilon(); | |
genType diff = sphereCenter - rayStarting; | |
typename genType::value_type t0 = dot(diff, rayNormalizedDirection); | |
typename genType::value_type dSquared = dot(diff, diff) - t0 * t0; | |
if( dSquared > sphereRadiusSquered ) | |
{ | |
return false; | |
} | |
typename genType::value_type t1 = sqrt( sphereRadiusSquered - dSquared ); | |
intersectionDistance = t0 > t1 + Epsilon ? t0 - t1 : t0 + t1; | |
return intersectionDistance > Epsilon; | |
} | |
template <typename genType> | |
GLM_FUNC_QUALIFIER bool intersectRaySphere | |
( | |
genType const & rayStarting, genType const & rayNormalizedDirection, | |
genType const & sphereCenter, const typename genType::value_type sphereRadius, | |
genType & intersectionPosition, genType & intersectionNormal | |
) | |
{ | |
typename genType::value_type distance; | |
if( intersectRaySphere( rayStarting, rayNormalizedDirection, sphereCenter, sphereRadius * sphereRadius, distance ) ) | |
{ | |
intersectionPosition = rayStarting + rayNormalizedDirection * distance; | |
intersectionNormal = (intersectionPosition - sphereCenter) / sphereRadius; | |
return true; | |
} | |
return false; | |
} | |
template <typename genType> | |
GLM_FUNC_QUALIFIER bool intersectLineSphere | |
( | |
genType const & point0, genType const & point1, | |
genType const & sphereCenter, typename genType::value_type sphereRadius, | |
genType & intersectionPoint1, genType & intersectionNormal1, | |
genType & intersectionPoint2, genType & intersectionNormal2 | |
) | |
{ | |
typename genType::value_type Epsilon = std::numeric_limits<typename genType::value_type>::epsilon(); | |
genType dir = normalize(point1 - point0); | |
genType diff = sphereCenter - point0; | |
typename genType::value_type t0 = dot(diff, dir); | |
typename genType::value_type dSquared = dot(diff, diff) - t0 * t0; | |
if( dSquared > sphereRadius * sphereRadius ) | |
{ | |
return false; | |
} | |
typename genType::value_type t1 = sqrt( sphereRadius * sphereRadius - dSquared ); | |
if( t0 < t1 + Epsilon ) | |
t1 = -t1; | |
intersectionPoint1 = point0 + dir * (t0 - t1); | |
intersectionNormal1 = (intersectionPoint1 - sphereCenter) / sphereRadius; | |
intersectionPoint2 = point0 + dir * (t0 + t1); | |
intersectionNormal2 = (intersectionPoint2 - sphereCenter) / sphereRadius; | |
return true; | |
} | |
}//namespace glm |