Method RayCast

Source/Engine/Tools/ModelTool/MeshAccelerationStructure.cpp:615–672

}

bool MeshAccelerationStructure::RayCast(const Ray& ray, Real& hitDistance, Vector3& hitNormal, Triangle& hitTriangle, Real maxDistance) const
{
    hitDistance = maxDistance;

    // BVH
    if (_bvh.Count() != 0)
    {
        return RayCastBVH(0, ray, hitDistance, hitNormal, hitTriangle);
    }

    // Brute-force
    {
        Vector3 normal;
        Real distance;
        bool hit = false;
        for (const Mesh& meshData : _meshes)
        {
            if (!meshData.Bounds.Intersects(ray))
                continue;
            const Float3* vb = meshData.VertexBuffer.Get<Float3>();
            if (meshData.Use16BitIndexBuffer)
            {
                const uint16* ib16 = meshData.IndexBuffer.Get<uint16>();
                for (int32 i = 0; i < meshData.Indices;)
                {
                    Vector3 v0 = vb[ib16[i++]];
                    Vector3 v1 = vb[ib16[i++]];
                    Vector3 v2 = vb[ib16[i++]];
                    if (CollisionsHelper::RayIntersectsTriangle(ray, v0, v1, v2, distance, normal) && distance < hitDistance)
                    {
                        hitDistance = distance;
                        hitNormal = normal;
                        hitTriangle = Triangle(v0, v1, v2);
                        hit = true;
                    }
                }
            }
            else
            {
                const uint32* ib32 = meshData.IndexBuffer.Get<uint32>();
                for (int32 i = 0; i < meshData.Indices;)
                {
                    Vector3 v0 = vb[ib32[i++]];
                    Vector3 v1 = vb[ib32[i++]];
                    Vector3 v2 = vb[ib32[i++]];
                    if (CollisionsHelper::RayIntersectsTriangle(ray, v0, v1, v2, distance, normal) && distance < hitDistance)
                    {
                        hitDistance = distance;
                        hitNormal = normal;
                        hitTriangle = Triangle(v0, v1, v2);
                        hit = true;
                    }
                }
            }
        }
        return hit;
    }
}