To project lidar points to an image, we first need to represent the lidar points from the lidar [Coordinate Frame] to the camera coordinate frame. We can do this by projecting the lidar points to the car coordinate frame and then projecting the points from the car coordinate frame to the camera coordinate frame. Both the camera and lidar coordinate systems have their \(x\) axis in the front, the \(y\) axis to the left and the \(z\) axis pointing up. However in the camera sensor plane the \(x\) axis is pointing to the right, the \(y\) axis is pointing to the down and the \(z\) axis is pointing to the front. Therefore we need to represent the points in the camera coordinate frame in terms of the sensor coordinate frame. We do this by rotating the points in the camera frame first along the \(z\) axis by an angle of \(90^\circ\) and then along the \(x\) axis by an angle of \(90^\circ\). After the new points are in the sensor frame, we can multiply the points with the [Camera Intrinsics] matrix to project the points in the sensor plane. The points are now in the [Homogeneous Coordinates] system. We can get the sensor plane coordinates of the points by dividing the \(x\) and \(y\) coordinates of the points with the \(z\) coordinates. After this, we eliminate the points which lie outside the image dimensions and finally display the points on the image.

## Todo

- Code for lidar to camera transform.