btVector3 getRayTo(int x,int y)
{
if (!m_glApp->m_instancingRenderer)
{
btAssert(0);
return btVector3(0,0,0);
}
float top = 1.f;
float bottom = -1.f;
float nearPlane = 1.f;
float tanFov = (top-bottom)*0.5f / nearPlane;
float fov = b3Scalar(2.0) * b3Atan(tanFov);
btVector3 camPos,camTarget;
m_glApp->m_instancingRenderer->getCameraPosition(camPos);
m_glApp->m_instancingRenderer->getCameraTargetPosition(camTarget);
btVector3 rayFrom = camPos;
btVector3 rayForward = (camTarget-camPos);
rayForward.normalize();
float farPlane = 10000.f;
rayForward*= farPlane;
btVector3 rightOffset;
btVector3 m_cameraUp=btVector3(0,1,0);
btVector3 vertical = m_cameraUp;
btVector3 hor;
hor = rayForward.cross(vertical);
hor.normalize();
vertical = hor.cross(rayForward);
vertical.normalize();
float tanfov = tanf(0.5f*fov);
hor *= 2.f * farPlane * tanfov;
vertical *= 2.f * farPlane * tanfov;
b3Scalar aspect;
float width = m_glApp->m_instancingRenderer->getScreenWidth();
float height = m_glApp->m_instancingRenderer->getScreenHeight();
aspect = width / height;
hor*=aspect;
btVector3 rayToCenter = rayFrom + rayForward;
btVector3 dHor = hor * 1.f/width;
btVector3 dVert = vertical * 1.f/height;
btVector3 rayTo = rayToCenter - 0.5f * hor + 0.5f * vertical;
rayTo += btScalar(x) * dHor;
rayTo -= btScalar(y) * dVert;
return rayTo;
}
void GLInstancingRenderer::getMouseDirection(float* dir, int x, int y)
{
float top = 1.f;
float bottom = -1.f;
float nearPlane = 1.f;
float tanFov = (top-bottom)*0.5f / nearPlane;
float fov = b3Scalar(2.0) * b3Atan(tanFov);
b3Vector3 rayFrom = m_data->m_cameraPosition;
b3Vector3 rayForward = (m_data->m_cameraTargetPosition-m_data->m_cameraPosition);
rayForward.normalize();
float farPlane = 10000.f;
rayForward*= farPlane;
b3Vector3 rightOffset;
b3Vector3 vertical = m_data->m_cameraUp;
b3Vector3 hor;
hor = rayForward.cross(vertical);
hor.normalize();
vertical = hor.cross(rayForward);
vertical.normalize();
float tanfov = tanf(0.5f*fov);
hor *= 2.f * farPlane * tanfov;
vertical *= 2.f * farPlane * tanfov;
b3Scalar aspect;
aspect = m_screenWidth / (b3Scalar)m_screenHeight;
hor*=aspect;
b3Vector3 rayToCenter = rayFrom + rayForward;
b3Vector3 dHor = hor * 1.f/float(m_screenWidth);
b3Vector3 dVert = vertical * 1.f/float(m_screenHeight);
b3Vector3 rayTo = rayToCenter - 0.5f * hor + 0.5f * vertical;
rayTo += b3Scalar(x) * dHor;
rayTo -= b3Scalar(y) * dVert;
dir[0] = rayTo[0];
dir[1] = rayTo[1];
dir[2] = rayTo[2];
}
