camera speed meaning

[cats-food]

Hi, thanks for sharing the great work! I have a little question about the camera control.

I wonder does the camera speed value have its practical meaning? say, when setting speed=0.5, what does the value 0.5 refer to? or is it just a relative indicator? Also, could you please give me some hint how to do if I want to move the camera for a certain distance, like pan right for 20 pixels? Thanks for your help :)