metaforce/Runtime/Collision/CollisionUtil.cpp

#include "CollisionUtil.hpp"
#include "CCollisionInfo.hpp"
#include "CCollisionInfoList.hpp"

namespace urde
{
namespace CollisionUtil
{

bool LineIntersectsOBBox(const zeus::COBBox& obb, const zeus::CMRay& ray, float& d)
{
    const zeus::CVector3f transXf = obb.transform.toMatrix4f().vec[0].toVec3f();
    return RayAABoxIntersection(ray.getInvUnscaledTransformRay(obb.transform), {-obb.extents, obb.extents},
                                transXf, d);
}

u32 RayAABoxIntersection(const zeus::CMRay& ray, const zeus::CAABox& box, const zeus::CVector3f&, float& d)
{

    return 0;
}

u32 RaySphereIntersection_Double(const zeus::CSphere&, const zeus::CVector3f &, const zeus::CVector3f &, double &)
{
    return 0;
}

bool RaySphereIntersection(const zeus::CSphere& sphere, const zeus::CVector3f& pos, const zeus::CVector3f& dir,
                           float mag, float& T, zeus::CVector3f& point)
{
    zeus::CVector3f rayToSphere = sphere.position - pos;
    float magSq = rayToSphere.magSquared();
    float dirDot = rayToSphere.dot(dir);
    float radSq = sphere.radius * sphere.radius;
    if (dirDot < 0.f && magSq > radSq)
        return false;
    float intersectSq = radSq - (magSq - dirDot * dirDot);
    if (intersectSq < 0.f)
        return false;
    T = magSq > radSq ? dirDot - std::sqrt(intersectSq) : dirDot + std::sqrt(intersectSq);
    if (T < mag || mag == 0.f)
    {
        point = pos + T * dir;
        return true;
    }
    return false;
}

void FilterOutBackfaces(const zeus::CVector3f& vec, const CCollisionInfoList& in, CCollisionInfoList& out)
{
    if (vec.canBeNormalized())
    {
        zeus::CVector3f norm = vec.normalized();
        for (const CCollisionInfo& info : in)
        {
            if (info.GetNormalLeft().dot(norm) < 0.001f)
                out.Add(info, false);
        }
    }
    else
    {
        out = in;
    }
}

void FilterByClosestNormal(const zeus::CVector3f& norm, const CCollisionInfoList& in, CCollisionInfoList& out)
{
    float maxDot = -1.1f;
    int idx = -1;
    int i=0;
    for (const CCollisionInfo& info : in)
    {
        float dot = info.GetNormalLeft().dot(norm);
        if (dot > maxDot)
        {
            maxDot = dot;
            idx = i;
        }
        ++i;
    }

    if (idx != -1)
        out.Add(in.GetItem(i), false);
}

static const zeus::CVector3f AABBNormalTable[] =
{
    {-1.f, 0.f, 0.f},
    {1.f, 0.f, 0.f},
    {0.f, -1.f, 0.f},
    {0.f, 1.f, 0.f},
    {0.f, 0.f, -1.f},
    {0.f, 0.f, 1.f}
};

bool AABoxAABoxIntersection(const zeus::CAABox& aabb0, const CMaterialList& list0,
                            const zeus::CAABox& aabb1, const CMaterialList& list1,
                            CCollisionInfoList& infoList)
{
    zeus::CAABox boolAABB = aabb0.booleanIntersection(aabb1);
    if (boolAABB.invalid())
        return false;

    /* TODO: Finish */

    if (!infoList.GetCount())
    {
        infoList.Add(CCollisionInfo(boolAABB, list0, list1, AABBNormalTable[4], -AABBNormalTable[4]), false);
        infoList.Add(CCollisionInfo(boolAABB, list0, list1, AABBNormalTable[5], -AABBNormalTable[5]), false);
    }

    return true;
}

bool AABoxAABoxIntersection(const zeus::CAABox& aabb0, const zeus::CAABox& aabb1)
{
    return aabb0.intersects(aabb1);
}

}
}