3.3.5.3 Sending an RDPINPUT_TOUCH_EVENT_PDU message
The structure and fields of the RDPINPUT_TOUCH_EVENT_PDU message are specified in section 2.2.3.3.
Each RDPINPUT_TOUCH_EVENT_PDU (section 2.2.3.3) message contains an array of RDPINPUT_TOUCH_FRAME (section 2.2.3.3.1) structures, and each frame contains an array of RDPINPUT_TOUCH_CONTACT (section 2.2.3.3.1.1) structures. Every RDPINPUT_TOUCH_CONTACT structure represents the state and attributes of an active contact; see section 3.1.1.1 for a description of permissible touch contact state transitions.
Every touch frame received by the client from a touch digitizer MUST be encoded as an RDPINPUT_TOUCH_FRAME structure, the contacts being encoded as RDPINPUT_TOUCH_CONTACT structures. The number of encoded frames depends on the rate at which the digitizer generates touch frames. Once the touch frames have been encoded, they MUST be encapsulated in an RDPINPUT_TOUCH_EVENT_PDU message.