void Pick3DObjectExample::CreateWorldSpaceRayFromScreen(const Eegeo::v2& screenPoint, Ray& ray)
{
const Eegeo::Camera::RenderCamera& renderCamera = m_cameraProvider.GetRenderCamera();
//normalize the point
double nx = 2.0 * screenPoint.GetX() / m_renderContext.GetScreenWidth() - 1;
double ny = - 2.0 * screenPoint.GetY() / m_renderContext.GetScreenHeight() + 1;
//prepare near and far points
Eegeo::v4 near(nx, ny, 0.0f, 1.0);
Eegeo::v4 far(nx, ny, 1.0f, 1.0);
Eegeo::m44 invVP;
Eegeo::m44::Inverse(invVP, renderCamera.GetViewProjectionMatrix());
//unproject the points
Eegeo::v4 unprojectedNear = Eegeo::v4::Mul(near, invVP);
Eegeo::v4 unprojectedFar = Eegeo::v4::Mul(far, invVP);
//convert to 3d
Eegeo::v3 unprojectedNearWorld = unprojectedNear / unprojectedNear.GetW();
Eegeo::v3 unprojectedFarWorld = unprojectedFar / unprojectedFar.GetW();
//check intersection with a ray cast from camera position
ray.m_origin = renderCamera.GetEcefLocation();
ray.m_direction = (unprojectedNearWorld - unprojectedFarWorld).Norm();
}
void PositionJavaPinButtonExample::Project (const Eegeo::Space::LatLongAltitude& location, Eegeo::v3& screenPosition)
{
//project a 3D Ecef location to the screen
Eegeo::m44 finalMatrix;
Eegeo::Camera::RenderCamera renderCamera(GetGlobeCameraController().GetRenderCamera());
Eegeo::m44::Mul (finalMatrix,
renderCamera.GetProjectionMatrix(),
renderCamera.GetViewMatrix());
Eegeo::v3 local = (location.ToECEF() - renderCamera.GetEcefLocation()).ToSingle();
Eegeo::v4 inVector(local, 1.0f);
// get clip space coords
Eegeo::v4 outVector = Eegeo::v4::Mul(inVector, finalMatrix);
// divide through by w to get normalized device space coords -- range [-1, 1]
screenPosition.SetX((outVector.GetX()/outVector.GetW()));
screenPosition.SetY((outVector.GetY()/outVector.GetW()));
screenPosition.SetZ((outVector.GetZ()/outVector.GetW()));
// transform from [-1, 1] to [0, 1]
screenPosition.SetX((screenPosition.GetX() + 1.0f) * 0.5f);
screenPosition.SetY(1.0f - ((screenPosition.GetY() + 1.0f) * 0.5f));
float viewport[] = {0, 0, renderCamera.GetViewportWidth(), renderCamera.GetViewportHeight()};
// transform from [0, 1] to screen coords.
screenPosition.SetX((screenPosition.GetX()*(viewport[2]-viewport[0])) + viewport[0]);
screenPosition.SetY((screenPosition.GetY()*(viewport[3]-viewport[1])) + viewport[1]);
}