Trace-line (World::Intersect) in Wildstar

[Master674]

Hey, decided to write a small guide as well (inspired by Jadd's post today) on how to use the games CWorld::GetIntersection function.

Type declarations and structs first:

typedef bool (__stdcall* CWorld__GetIntersection_t) (const Game::CWorld *pInstance, const Math::Vector4& start, const Math::Vector4& end,
	const Math::Vector4& up, Game::WorldIntersectionResult** intersectionResult, const Game::WorldIntersectionParams& params);

namespace Game {
	enum class WorldIntersectionFlags : uint32 {
		None = 0,
		All = ~None,
		Terrain = 0x1,
		Structure = 0x10
	};

#pragma pack(push, 1)
	struct WorldIntersectionParams {
		typedef int (__stdcall *callback_t) (void*, int);

		uint32       flags;    // @0
		uint32       unk1;     // @4 - 0
		uint32       unk2;     // @8 - 0 (bool?)
		callback_t   callback; // @C - function
		void        *classPtr; // @10 - gameMgr
		uint32       unk4;     // @14 - 0
		uint32       unk5;     // @18 - 0 (used if unk2 is set)
	};

	struct WorldIntersectionResult {
		struct {
			void(__stdcall* unk)(void*);
			void(__stdcall* destruct)(void*);
			void(__stdcall* initialize)(void*);
		}           *vftbl;    // @0 - vftable
		uint32       unk2;     // @4 - 1
		float        distance; // @8 - lerp from start
	};
#pragma pack(pop)
}

The game offsets you need (VTable shouldn't change much, should be easy to update).

class OffsetsX86 {
public:
	struct SGameManager {
		uint32 Ptr                     = 0x00872098; // 6745.10
		uint32 WorldPtr                = 0x00005FDC; // 6745.10
	} GameManager;

	struct SWorld {
		struct SVMT {
			uint32 GetIntersection = 51; // 6745.10
		} VMT;
	} World;
}

Usage (result will contain the hitpoint, if any):

bool CWorld::getIntersection(const Math::Vector3& start,
			     const Math::Vector3& end,
			     uint32 intersectionFlags,
			     Math::Vector3* result) const
{
	__declspec(align(16))
	Math::Vector4 startPt(start, 1.0f); // needs to be 16-byte aligned because of SIMD (they use aligned vectors for this)

	__declspec(align(16))
	Math::Vector4 endPt(end, 1.0f); // needs to be 16-byte aligned because of SIMD (they use aligned vectors for this)

	__declspec(align(16))
	Math::Vector4 unkVec(0, 1, 1, 0); // needs to be 16-byte aligned because of SIMD (they use aligned vectors for this)

	WorldIntersectionParams intersectParams = { 0 };
	WorldIntersectionResult *intersectResult = nullptr;
	intersectParams.flags = intersectionFlags;

	Delegates::CWorld__GetIntersection_t pGetIntersection = sMemory.getVFunc<Delegates::
		CWorld__GetIntersection_t>(getPointer(), sOffsets.GameData.World.VMT.GetIntersection);
	bool hasHit = pGetIntersection(this, startPt, endPt, unkVec, &intersectResult, intersectParams);

	if (intersectResult != nullptr) {
		intersectResult->vftbl->initialize(intersectResult);
		if (result != nullptr)
			*result = start + (end - start) * intersectResult->distance;
		intersectResult->vftbl->destruct(intersectResult); // need to do this or you will leak memory and crash the game at some point
	}

	return hasHit;
}

To get a pointer to the current CWorld instance, just use the GameMgr Ptr and add the WorldPtr.
Greets!