I want to implement an on board GUI where i first select a area and then i can write something in it but i'm stuck in first part where i have to select Billboard Text,

here is my Code for Picking:

    POINT ptCursor;
    	GetCursorPos(&ptCursor);
    	ScreenToClient(AngelCore::AngelSubSystemResources::WindowProperties::GetHWND(), &ptCursor);
    
    	UINT numOfVP = 1;
    	D3D11_VIEWPORT vp;
    	AngelCore::AngelSubSystemResources::GraphicDeviceResources::GetDeviceContext3D()->RSGetViewports(&numOfVP, &vp);
    
    
    	DirectX::XMFLOAT3 v;
    	v.x = (((2.0f * ptCursor.x) / vp.Width) - 1) / proj4X4._11;
    	v.y = -(((2.0f * ptCursor.y) / vp.Height) - 1) / proj4X4._22;
    	v.z = -1.0f;
    
    	DirectX::XMMATRIX translation = DirectX::XMMatrixTranslation(
    		      DirectX::XMVectorGetX(
    			AngelCore::AngelSubSystemResources::BaseCameraProperties::BCamera.GetCameraPosition())
    			, DirectX::XMVectorGetY(
    				AngelCore::AngelSubSystemResources::BaseCameraProperties::BCamera.GetCameraPosition())
    			, DirectX::XMVectorGetZ(
    					AngelCore::AngelSubSystemResources::BaseCameraProperties::BCamera.GetCameraPosition()));
    
    	DirectX::XMMATRIX worldView = View;
    	DirectX::XMMATRIX inv = DirectX::XMMatrixInverse(nullptr, worldView);
    	DirectX::XMFLOAT4X4 invWorldView4X4;
    	DirectX::XMStoreFloat4x4(&invWorldView4X4, inv);
    
    	DirectX::XMFLOAT3 vPickRayDir;
    	DirectX::XMFLOAT3 vPickRayOrig;
    
    	vPickRayDir.x = v.x * invWorldView4X4._11 + v.y * invWorldView4X4._21 + v.z * invWorldView4X4._31;
    	vPickRayDir.y = v.x * invWorldView4X4._12 + v.y * invWorldView4X4._22 + v.z * invWorldView4X4._32;
    	vPickRayDir.z = v.x * invWorldView4X4._13 + v.y * invWorldView4X4._23 + v.z * invWorldView4X4._33;
    	vPickRayOrig.x = invWorldView4X4._41;
    	vPickRayOrig.y = invWorldView4X4._42;
    	vPickRayOrig.z = invWorldView4X4._43;
    
    	DirectX::XMFLOAT3 rayObjOrigin, rayObjDirection;
    
    	DirectX::XMVECTOR rayOrig =  DirectX::XMVector3TransformCoord(DirectX::XMVectorSet(
    		vPickRayOrig.x, vPickRayOrig.y, vPickRayOrig.z, 1.0f), invWorld);
    
    	DirectX::XMVECTOR rayDir = DirectX::XMVector3TransformNormal(DirectX::XMVectorSet(
    		vPickRayDir.x, vPickRayDir.y, vPickRayDir.z, 1.0f), invWorld);
    
    	rayDir = DirectX::XMVector3Normalize(rayDir);

    float dist = 0;
    	if (b.Intersects(rayOrig,
    		rayDir, dist))
    	{
    		return true;
    	}

Here is the details:

Matrix translation do nothing.

"b" is the bounding box from the object that i want to check for ray intersection.

I also pass inverse world matrix to this function.

My code won't work correctly,it's like bounding box is moving with camera,every time i move camera it shows intersection in different position!

// Get Picking Ray from Camera

        Public Function GetPickingRay(sp As Vector2) As Ray
            Dim v1 As Vector3
            Dim v2 As Vector3           
            Dim vp as Matrix = GetViewProjMatrixFromCamera()
            Dim Point As Vector3 = New Vector3(sp.X, sp.Y, 0)
            v1 = Vector3.Unproject(Point, Viewport.X, Viewport.Y, Viewport.Width, Viewport.Height, Viewport.MinZ, Viewport.MaxZ, vp)
            Point.Z = 1
            v2 = Vector3.Unproject(Point, Viewport.X, Viewport.Y, Viewport.Width, Viewport.Height, Viewport.MinZ, Viewport.MaxZ, vp)

            Dim Loc As Vector3 = v1
            Dim Dir As Vector3 = Vector3.Normalize(v2 - v1)

            Return New Ray(Loc, Dir)
        End Function

...


// Get Ray at Mouse Position
    Private Function GetTransformedRay(MousePos As Vector2, worldMat As Matrix, Editor As TEditor) As Ray
        Dim cRay As Ray = Editor.MyView.Camera.GetPickingRay(MousePos)
        Dim InvMat As Matrix = Matrix.Invert(worldMat)
        Return New Ray(Vector3.TransformCoordinate(cRay.Position, InvMat), Vector3.TransformNormal(cRay.Direction, InvMat))
    End Function

Here some Code, how I am doing ray picking an object. Using the GetTransformRay function you will get the Ray in ObjectSpace for the Object you want to test.