Added method EntityFirstHitByRay, takes an Octree or a vector of sorted entities and outputs the frist entity hit by a ray.

include/Engine/Collision/Collision.h

@@ -20,6 +20,9 @@
 class World;
 struct ComponentWrapper;
 
+template<typename T>
+class Octree;
+
 namespace Collision
 {
 //Return true if the ray hits the box.
@@ -44,21 +47,24 @@ bool RayVsTriangle(const Ray& ray,
     float& outVCoord,
     bool trueOnNegativeDistance = false);
 //Return true if the ray hits any of the triangles in the model. Stops checking when a hit is detected.
-bool RayVsModel(const Ray& ray, 
+bool RayVsModel(const Ray& ray,
-    const std::vector<RawModel::Vertex>& modelVertices,
+    const RawModel::Vertex* modelVertices,
-    const std::vector<unsigned int>& modelIndices);
+    const std::vector<unsigned int>& modelIndices,
+    const glm::mat4& modelMatrix);
 //Return true if the ray hits any of the triangles in the model.
 //Also returns the position of the intersection point. Will loop through all the whole model indices.
 bool RayVsModel(const Ray& ray,
-    const std::vector<RawModel::Vertex>& modelVertices,
+    const RawModel::Vertex* modelVertices,
     const std::vector<unsigned int>& modelIndices,
+    const glm::mat4& modelMatrix,
     glm::vec3& outHitPosition);
 //Return true if the ray hits any of the triangles in the model.
 //Also returns the distance from the ray origin to the closest 
 //intersection point, and the barycentric u,v-coordinates. Will loop through all the whole model indices.
 bool RayVsModel(const Ray& ray,
-    const std::vector<RawModel::Vertex>& modelVertices,
+    const RawModel::Vertex* modelVertices,
     const std::vector<unsigned int>& modelIndices,
+    const glm::mat4& modelMatrix,
     float& outDistance,
     float& outUCoord,
     float& outVCoord);
@@ -81,6 +87,13 @@ bool AABBVsAABB(const AABB& a, const AABB& b, glm::vec3& minimumTranslation);
 // Calculates an absolute AABB from an entity AABB component
 boost::optional<EntityAABB> EntityAbsoluteAABB(EntityWrapper& entity, bool takeModelBox = false);
 boost::optional<EntityAABB> AbsoluteAABBExplosionEffect(EntityWrapper& entity);
+//Returns the first entity hit by the input ray. entitiesPotentiallyHitSorted needs to be sorted 
+//by their distance to the ray, e.g. result from Octree<EntityAABB>::ObjectsPossiblyHitByRay.
+//Returns boost::none if none was hit. outDistance will be the distance to the intersection point if the ray intersects.
+boost::optional<EntityAABB> EntityFirstHitByRay(const Ray& ray, std::vector<EntityAABB> entitiesPotentiallyHitSorted, float outDistance, glm::vec3& outIntersectPos);
+//Returns the first entity hit by the input ray that exists in the octree.
+//outDistance will be the distance to the intersection point if the ray intersects. 
+boost::optional<EntityAABB> EntityFirstHitByRay(const Ray& ray, Octree<EntityAABB>* octree, float outDistance, glm::vec3& outIntersectPos);
 
 }
 

include/Engine/Core/Octree.h

@@ -43,6 +43,8 @@ public:
     void ObjectsInSameRegion(const Box& box, std::vector<T>& outObjects);
     //Get the objects that are inside the frustum, the objects are put in outObjects.
     void ObjectsInFrustum(const Frustum& frustum, std::vector<T>& outObjects);
+    //Get objects, which AABB the input ray intersects, the objects are put in outObjects.
+    void ObjectsPossiblyHitByRay(const Ray& ray, std::vector<T>& outObjects);
     //Empty the tree of all objects, static and dynamic.
     void ClearObjects();
     //Empty the tree of all dynamic objects. Static objects remain in the tree.
@@ -102,6 +104,8 @@ struct Child
     void ObjectsInSameRegion(const Box& box, std::vector<T>& outObjects) const;
     template<typename T>
     void ObjectsInFrustum(const Frustum& frustum, std::vector<T>& outObjects, bool takeAllDontTest) const;
+    template<typename T>
+    void ObjectsPossiblyHitByRay(const Ray& ray, std::vector<T>& outObjects) const;
     void ClearObjects();
     void ClearDynamicObjects();
     bool RayCollides(const Ray& ray, Output& data) const;
@@ -121,6 +125,15 @@ struct Child
     std::vector<int> childIndicesContainingBox(const AABB& box) const;
 };
 
+//To be able to sort child nodes and contained objects based on distance to ray origin.
+struct RaySorterInfo
+{
+    int Index;
+    float Distance;
+};
+
+bool isFirstLower(const RaySorterInfo& first, const RaySorterInfo& second);
+
 }
 
 template<typename T>
@@ -166,6 +179,13 @@ void Octree<T>::ObjectsInFrustum(const Frustum& frustum, std::vector<T>& outObje
     m_Root->ObjectsInFrustum(frustum, outObjects, false);
 }
 
+template<typename T>
+void Octree<T>::ObjectsPossiblyHitByRay(const Ray& ray, std::vector<T>& outObjects)
+{
+    falsifyObjectChecks();
+    m_Root->ObjectsPossiblyHitByRay(ray, outObjects);
+}
+
 template<typename T>
 void Octree<T>::ClearObjects()
 {
@@ -284,4 +304,59 @@ void OctSpace::Child::ObjectsInFrustum(const Frustum& frustum, std::vector<T>& o
     }
 }
 
+template<typename T>
+void OctSpace::Child::ObjectsPossiblyHitByRay(const Ray& ray, std::vector<T>& outObjects) const
+{
+    //If the node AABB is missed, everything it contains is missed.
+    if (Collision::RayAABBIntr(ray, m_Box)) {
+        //If the ray shoots the tree, and it is a parent.
+        if (hasChildren()) {
+            //Sort children according to their distance from the ray origin.
+            std::vector<RaySorterInfo> childInfos;
+            childInfos.resize(8);
+            for (int i = 0; i < 8; ++i) {
+                childInfos[i] = { i, glm::distance(ray.Origin(), m_Children[i]->m_Box.Origin()) };
+            }
+            std::sort(childInfos.begin(), childInfos.end(), isFirstLower);
+            //Loop through the children, starting with the one closest to the ray origin. I.e the first to be hit.
+            for (const RaySorterInfo& info : childInfos) {
+                m_Children[info.Index]->ObjectsPossiblyHitByRay(ray, outObjects);
+            }
+        } else {
+            //Check against boxes in the node.
+            bool intersected = false;
+            float dist;
+            //Sort all contained objects according to the distance from the ray origin to 
+            //the intersection, if they are intersecting.
+            std::vector<RaySorterInfo> objectHitInfos;
+            objectHitInfos.reserve(m_StaticObjIndices.size() + m_DynamicObjIndices.size());
+            for (int i : m_StaticObjIndices) {
+                //If we haven't tested against this object before, and the ray hits.
+                if (!m_StaticObjectsRef[i].Checked &&
+                        Collision::RayVsAABB(ray, *m_StaticObjectsRef[i].Box, dist)) {
+                    objectHitInfos.push_back({ i, dist });
+                }
+                m_StaticObjectsRef[i].Checked = true;
+            }
+            for (int i : m_DynamicObjIndices) {
+                //If we haven't tested against this object before, and the ray hits.
+                if (!m_DynamicObjectsRef[i].Checked &&
+                        Collision::RayVsAABB(ray, *m_DynamicObjectsRef[i].Box, dist)) {
+                    objectHitInfos.push_back({ i + (int)m_StaticObjIndices.size(), dist });
+                }
+                m_DynamicObjectsRef[i].Checked = true;
+            }
+            std::sort(objectHitInfos.begin(), objectHitInfos.end(), isFirstLower);
+            int startSize = (int)outObjects.size();
+            outObjects.resize(startSize + objectHitInfos.size());
+            for (int i = 0; i < objectHitInfos.size(); ++i) {
+                outObjects[startSize + i] = (objectHitInfos[i].Index < m_StaticObjIndices.size()) ?
+                    *static_cast<T*>(m_StaticObjectsRef[objectHitInfos[i].Index].Box.get()) :
+                    *static_cast<T*>(m_DynamicObjectsRef[objectHitInfos[i].Index - m_StaticObjIndices.size()].Box.get());
+            }
+        }
+    }
+}
+
+
 #endif

src/Engine/Collision/Collision.cpp

@@ -6,6 +6,7 @@
 #include "Core/World.h"
 #include "Rendering/Model.h"
 #include "imgui/imgui.h"
+#include "Core/Octree.h"
 
 namespace Collision
 {
@@ -145,13 +146,14 @@ bool RayVsTriangle(const Ray& ray,
 }
 
 bool RayVsModel(const Ray& ray,
-    const std::vector<RawModel::Vertex>& modelVertices,
+    const RawModel::Vertex* modelVertices,
-    const std::vector<unsigned int>& modelIndices)
+    const std::vector<unsigned int>& modelIndices,
+    const glm::mat4& modelMatrix)
 {
-    for (int i = 0; i < modelIndices.size(); ++i) {
+    for (int i = 0; i < modelIndices.size();) {
-        glm::vec3 v0 = modelVertices[modelIndices[i]].Position;
+        glm::vec3 v0 = Transform::TransformPoint(modelVertices[modelIndices[i++]].Position, modelMatrix);
-        glm::vec3 v1 = modelVertices[modelIndices[++i]].Position;
+        glm::vec3 v1 = Transform::TransformPoint(modelVertices[modelIndices[i++]].Position, modelMatrix);
-        glm::vec3 v2 = modelVertices[modelIndices[++i]].Position;
+        glm::vec3 v2 = Transform::TransformPoint(modelVertices[modelIndices[i++]].Position, modelMatrix);
         if (RayVsTriangle(ray, v0, v1, v2)) {
             return true;
         }
@@ -192,19 +194,20 @@ bool RayVsTriangle(const Ray& ray,
 }
 
 bool RayVsModel(const Ray& ray,
-    const std::vector<RawModel::Vertex>& modelVertices,
+    const RawModel::Vertex* modelVertices,
     const std::vector<unsigned int>& modelIndices,
+    const glm::mat4& modelMatrix,
     float& outDistance,
     float& outUCoord,
     float& outVCoord)
 {
     outDistance = INFINITY;
     bool hit = false;
-    for (int i = 0; i < modelIndices.size(); ++i) {
+    for (int i = 0; i < modelIndices.size();) {
-        glm::vec3 v0 = modelVertices[modelIndices[i]].Position;
+        glm::vec3 v0 = Transform::TransformPoint(modelVertices[modelIndices[i++]].Position, modelMatrix);
-        glm::vec3 v1 = modelVertices[modelIndices[++i]].Position;
+        glm::vec3 v1 = Transform::TransformPoint(modelVertices[modelIndices[i++]].Position, modelMatrix);
-        glm::vec3 v2 = modelVertices[modelIndices[++i]].Position;
+        glm::vec3 v2 = Transform::TransformPoint(modelVertices[modelIndices[i++]].Position, modelMatrix);
-        float dist;
+        float dist = INFINITY;
         float u;
         float v;
         if (RayVsTriangle(ray, v0, v1, v2, dist, u, v)) {
@@ -218,14 +221,15 @@ bool RayVsModel(const Ray& ray,
 }
 
 bool RayVsModel(const Ray& ray,
-    const std::vector<RawModel::Vertex>& modelVertices,
+    const RawModel::Vertex* modelVertices,
     const std::vector<unsigned int>& modelIndices,
+    const glm::mat4& modelMatrix,
     glm::vec3& outHitPosition)
 {
     float u;
     float v;
     float dist;
-    bool hit = RayVsModel(ray, modelVertices, modelIndices, dist, u, v);
+    bool hit = RayVsModel(ray, modelVertices, modelIndices, modelMatrix, dist, u, v);
     outHitPosition = ray.Origin() + dist * ray.Direction();
     return hit;
 }
@@ -572,11 +576,11 @@ boost::optional<EntityAABB> EntityAbsoluteAABB(EntityWrapper& entity, bool takeM
         ComponentWrapper& cAABB = entity["AABB"];
         modelSpaceBox = EntityAABB::FromOriginSize((glm::vec3)cAABB["Origin"], (glm::vec3)cAABB["Size"]);
     } else if (entity.HasComponent("Model")) {
-        Model* model;
         std::string res = entity["Model"]["Resource"];
         if (res.empty()) {
             return boost::none;
         }
+        Model* model;
         try {
             model = ResourceManager::Load<::Model, true>(res);
         } catch (const Resource::StillLoadingException&) {
@@ -638,4 +642,36 @@ boost::optional<EntityAABB> AbsoluteAABBExplosionEffect(EntityWrapper& entity)
     return aabb;
 }
 
+boost::optional<EntityAABB> EntityFirstHitByRay(const Ray& ray, std::vector<EntityAABB> entitiesPotentiallyHitSorted, float outDistance, glm::vec3& outIntersectPos)
+{
+    for (EntityAABB& entityBox : entitiesPotentiallyHitSorted) {
+        if (!entityBox.Entity.HasComponent("Model")) {
+            continue;
+        }
+        std::string res = entityBox.Entity["Model"]["Resource"];
+        if (res.empty()) {
+            continue;
+        }
+        Model* model;
+        try {
+            model = ResourceManager::Load<::Model, true>(res);
+        } catch (const std::exception&) {
+            continue;
+        }
+        float u, v;
+        if (RayVsModel(ray, model->Vertices(), model->m_RawModel->m_Indices, Transform::ModelMatrix(entityBox.Entity), outDistance, u, v)) {
+            outIntersectPos = ray.Origin() + outDistance * ray.Direction();
+            return entityBox;
+        }
+    }
+    return boost::none;
+}
+
+boost::optional<EntityAABB> EntityFirstHitByRay(const Ray& ray, Octree<EntityAABB>* octree, float outDistance, glm::vec3& outIntersectPos)
+{
+    std::vector<EntityAABB> outObjects;
+    octree->ObjectsPossiblyHitByRay(ray, outObjects);
+    return Collision::EntityFirstHitByRay(ray, outObjects, outDistance, outIntersectPos);
+}
+
 }

src/Engine/Core/Octree.cpp

@@ -5,22 +5,6 @@
 #include "Core/Octree.h"
 #include "Collision/Collision.h"
 
-namespace
-{
-//To be able to sort nodes based on distance to ray origin.
-struct ChildInfo
-{
-    int Index;
-    float Distance;
-};
-
-bool isFirstLower(const ChildInfo& first, const ChildInfo& second)
-{
-    return first.Distance < second.Distance;
-}
-
-}
-
 namespace OctSpace
 {
 
@@ -123,14 +107,14 @@ bool Child::RayCollides(const Ray& ray, OctSpace::Output& data) const
         //If the ray shoots the tree, and it is a parent to 8 children :o
         if (hasChildren()) {
             //Sort children according to their distance from the ray origin.
-            std::vector<ChildInfo> childInfos;
+            std::vector<RaySorterInfo> childInfos;
             childInfos.reserve(8);
             for (int i = 0; i < 8; ++i) {
                 childInfos.push_back({ i, glm::distance(ray.Origin(), m_Children[i]->m_Box.Origin()) });
             }
             std::sort(childInfos.begin(), childInfos.end(), isFirstLower);
             //Loop through the children, starting with the one closest to the ray origin. I.e the first to be hit.
-            for (const ChildInfo& info : childInfos) {
+            for (const RaySorterInfo& info : childInfos) {
                 if (m_Children[info.Index]->RayCollides(ray, data)) {
                     return true;
                 }
@@ -275,4 +259,9 @@ std::vector<int> Child::childIndicesContainingBox(const AABB& box) const
     }
 }
 
+bool isFirstLower(const RaySorterInfo& first, const RaySorterInfo& second)
+{
+    return first.Distance < second.Distance;
+}
+
 }