Merge pull request #123 from teamfisk/BoxModelCollision

Falling through ground + dash fix.

include/Engine/Collision/CollisionSystem.h

@@ -15,11 +15,11 @@ class CollisionSystem : public PureSystem
 public:
     CollisionSystem(SystemParams params, Octree<EntityAABB>* octree)
         : System(params)
-        , PureSystem("Collidable")
+        , PureSystem("Physics")
         , m_Octree(octree)
     { }
 
-    virtual void UpdateComponent(EntityWrapper& entity, ComponentWrapper& component, double dt) override;
+    virtual void UpdateComponent(EntityWrapper& entity, ComponentWrapper& cPhysics, double dt) override;
 
 private:
     Octree<EntityAABB>* m_Octree;

resources/Schema/Components/Physics.xml

@@ -2,6 +2,7 @@
 <Physics xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="Physics.xsd">
 	<Velocity X="0" Y="0" Z="0"/>
 	<Gravity>true</Gravity>
+	<PrevOrigin X="-9876.5" Y="-9876.5" Z="-9876.5"/>
 	<IsOnGround>false</IsOnGround>
 	<VerticalStepHeight>0.33</VerticalStepHeight>
 </Physics>

resources/Schema/Components/Physics.xsd

@@ -13,6 +13,7 @@
 					<xs:annotation><xs:documentation>m/s^2</xs:documentation></xs:annotation>
 				</xs:element>
 				<xs:element name="Gravity" type="t:bool" minOccurs="0"/>
+				<xs:element name="PrevOrigin" type="t:Vector" minOccurs="0"/>
 				<xs:element name="IsOnGround" type="t:bool" minOccurs="0"/>
 				<xs:element name="VerticalStepHeight" type="t:double" minOccurs="0">
 					<xs:annotation><xs:documentation>The largest height of a "stair-step" that can be walked over</xs:documentation></xs:annotation>

src/Engine/Collision/Collision.cpp

@@ -207,7 +207,7 @@ bool RayVsModel(const Ray& ray,
         glm::vec3 v0 = Transform::TransformPoint(modelVertices[modelIndices[i++]].Position, modelMatrix);
         glm::vec3 v1 = Transform::TransformPoint(modelVertices[modelIndices[i++]].Position, modelMatrix);
         glm::vec3 v2 = Transform::TransformPoint(modelVertices[modelIndices[i++]].Position, modelMatrix);
-        float dist = INFINITY;
+        float dist = outDistance;
         float u;
         float v;
         if (RayVsTriangle(ray, v0, v1, v2, dist, u, v)) {

src/Engine/Collision/CollisionSystem.cpp

@@ -3,24 +3,71 @@
 #include "Core/AABB.h"
 #include "Rendering/Model.h"
 
-void CollisionSystem::UpdateComponent(EntityWrapper& entity, ComponentWrapper& component, double dt)
+void CollisionSystem::UpdateComponent(EntityWrapper& entity, ComponentWrapper& cPhysics, double dt)
 {
-    if (!entity.HasComponent("Physics")) {
+    if (!entity.HasComponent("Collidable")) {
         return;
     }
-    ComponentWrapper& cPhysics = entity["Physics"];
-
     boost::optional<EntityAABB> boundingBox = Collision::EntityAbsoluteAABB(entity);
     if (!boundingBox) {
         return;
     }
     ComponentWrapper& cTransform = entity["Transform"];
     EntityAABB& boxA = *boundingBox;
+    bool everHitTheGround = false;
+
+    glm::vec3 size = boxA.Size();
+    float diameter = std::min(size.x, size.z);
+    glm::vec3 prevOrigin = (glm::vec3)cPhysics["PrevOrigin"];
+    glm::vec3 toCurrentPos = boxA.Origin() - prevOrigin;
+    float rayLength = glm::length(toCurrentPos) + 0.5f*diameter;
+    //If the entity has moved farther than the size of its box, we need to handle it specially.
+    bool traceCollision = rayLength > diameter;
+    //hack solution: If prevOrigin is less than -9000 in all dimensions, 
+    //then it means it is not set, i.e. this is the first collision check for the entity.
+    if (traceCollision && glm::any(glm::greaterThan((glm::vec3)cPhysics["PrevOrigin"], glm::vec3(-9000.f)))) {
+        Ray ray(prevOrigin, toCurrentPos);
+        m_OctreeResult.clear();
+        m_Octree->ObjectsPossiblyHitByRay(ray, m_OctreeResult);
+        for (auto& boxB : m_OctreeResult) {
+            if (boxA.Entity == boxB.Entity) {
+                continue;
+            }
+            bool hit;
+            float dist;
+            if (boxB.Entity.HasComponent("Model")) {
+                RawModel* model;
+                std::string res = (std::string)boxB.Entity["Model"]["Resource"];
+                try {
+                    model = ResourceManager::Load<RawModel, true>(res);
+                } catch (const std::exception&) {
+                    continue;
+                }
+                float u, v;
+                hit = Collision::RayVsModel(ray, model->Vertices(), model->m_Indices, Transform::ModelMatrix(boxB.Entity), dist, u, v);
+            } else {
+                hit = Collision::RayVsAABB(ray, boxB, dist);
+            }
+            if (hit && dist < rayLength) {
+                //Set the entity to where it was colliding, minus the maximum box size. 
+                //TODO: Perhaps this should be done slightly more properly.
+                glm::vec3 newOriginPos = ray.Origin() + (dist - 0.707107f*diameter) * ray.Direction();
+                glm::vec3 resolve = newOriginPos - boxA.Origin();
+                (glm::vec3&)cTransform["Position"] += resolve;
+                boxA = *Collision::EntityAbsoluteAABB(entity);
+                if (resolve.y > 0) {
+                    everHitTheGround = true;
+                    (bool)cPhysics["IsOnGround"] = true;
+                    ((glm::vec3&)cPhysics["Velocity"]).y = 0.f;
+                }
+                break;
+            }
+        }
+    }
 
     // Collide against octree items
     m_OctreeResult.clear();
     m_Octree->ObjectsInSameRegion(*boundingBox, m_OctreeResult);
-    bool everHitTheGround = false;
     for (auto& boxB : m_OctreeResult) {
         glm::vec3 resolutionVector;
         if (boxA.Entity == boxB.Entity) {
@@ -64,4 +111,6 @@ void CollisionSystem::UpdateComponent(EntityWrapper& entity, ComponentWrapper& c
     if (!everHitTheGround) {
         (bool)cPhysics["IsOnGround"] = false;
     }
+
+    (glm::vec3&)cPhysics["PrevOrigin"] = boxA.Origin();
 }