I use stm32f103c8t6 and I want to run USB HID Mouse , I can connect to my PC and change the position of mouse cursor
but I can't read the current mouse cursor position to use that , I can just add the X and Y value of cursor I use USBD_HID_SendReport( &USBD_Device , Buffer , 4 ) ; to do that
Nothing you can do. All what you can do is written in report descriptor. It can only send data to host according to defined rules.
Mouse position is relative. If you want absolute, you may try use emulated touchpad, not mouse.