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Diffstat (limited to 'src/include/glm/gtx/intersect.inl')
| -rw-r--r-- | src/include/glm/gtx/intersect.inl | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/src/include/glm/gtx/intersect.inl b/src/include/glm/gtx/intersect.inl new file mode 100644 index 0000000..fc44f25 --- /dev/null +++ b/src/include/glm/gtx/intersect.inl @@ -0,0 +1,200 @@ +/// @ref gtx_intersect
+
+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(glm::abs(d) > Epsilon) // if dir and planeNormal are not perpendicular
+ {
+ typename genType::value_type const tmp_intersectionDistance = glm::dot(planeOrig - orig, planeNormal) / d;
+ if (tmp_intersectionDistance > static_cast<typename genType::value_type>(0)) { // allow only intersections
+ intersectionDistance = tmp_intersectionDistance;
+ return true;
+ }
+ }
+
+ return false;
+ }
+
+ template<typename T, qualifier Q>
+ GLM_FUNC_QUALIFIER bool intersectRayTriangle
+ (
+ vec<3, T, Q> const& orig, vec<3, T, Q> const& dir,
+ vec<3, T, Q> const& vert0, vec<3, T, Q> const& vert1, vec<3, T, Q> const& vert2,
+ vec<2, T, Q>& baryPosition, T& distance
+ )
+ {
+ // find vectors for two edges sharing vert0
+ vec<3, T, Q> const edge1 = vert1 - vert0;
+ vec<3, T, Q> const edge2 = vert2 - vert0;
+
+ // begin calculating determinant - also used to calculate U parameter
+ vec<3, T, Q> const p = glm::cross(dir, edge2);
+
+ // if determinant is near zero, ray lies in plane of triangle
+ T const det = glm::dot(edge1, p);
+
+ vec<3, T, Q> Perpendicular(0);
+
+ if(det > std::numeric_limits<T>::epsilon())
+ {
+ // calculate distance from vert0 to ray origin
+ vec<3, T, Q> const dist = orig - vert0;
+
+ // calculate U parameter and test bounds
+ baryPosition.x = glm::dot(dist, p);
+ if(baryPosition.x < static_cast<T>(0) || baryPosition.x > det)
+ return false;
+
+ // prepare to test V parameter
+ Perpendicular = glm::cross(dist, edge1);
+
+ // calculate V parameter and test bounds
+ baryPosition.y = glm::dot(dir, Perpendicular);
+ if((baryPosition.y < static_cast<T>(0)) || ((baryPosition.x + baryPosition.y) > det))
+ return false;
+ }
+ else if(det < -std::numeric_limits<T>::epsilon())
+ {
+ // calculate distance from vert0 to ray origin
+ vec<3, T, Q> const dist = orig - vert0;
+
+ // calculate U parameter and test bounds
+ baryPosition.x = glm::dot(dist, p);
+ if((baryPosition.x > static_cast<T>(0)) || (baryPosition.x < det))
+ return false;
+
+ // prepare to test V parameter
+ Perpendicular = glm::cross(dist, edge1);
+
+ // calculate V parameter and test bounds
+ baryPosition.y = glm::dot(dir, Perpendicular);
+ if((baryPosition.y > static_cast<T>(0)) || (baryPosition.x + baryPosition.y < det))
+ return false;
+ }
+ else
+ return false; // ray is parallel to the plane of the triangle
+
+ T inv_det = static_cast<T>(1) / det;
+
+ // calculate distance, ray intersects triangle
+ distance = glm::dot(edge2, Perpendicular) * inv_det;
+ baryPosition *= inv_det;
+
+ return true;
+ }
+
+ 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 Perpendicular = cross(dir, edge2);
+
+ float det = dot(edge1, Perpendicular);
+
+ if (det > -Epsilon && det < Epsilon)
+ return false;
+ typename genType::value_type inv_det = typename genType::value_type(1) / det;
+
+ genType Tengant = orig - vert0;
+
+ position.y = dot(Tengant, Perpendicular) * inv_det;
+ if (position.y < typename genType::value_type(0) || position.y > typename genType::value_type(1))
+ return false;
+
+ genType Cotengant = cross(Tengant, edge1);
+
+ position.z = dot(dir, Cotengant) * 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, Cotengant) * 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
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