IS SMALL

Introduction

The IS_SMALL packet is a general purpose packet comprised of 8 bytes. The packet is designed to prevent repeating a common structure which would be the same for many packets. Unlike the IS_TINY the IS_SMALL also contains the UVal, a 4 byte unsigned integer.

struct IS_SMALL // General purpose 8 byte packet
{
	byte	Size;		// 8
	byte	Type;		// ISP_SMALL
	byte	ReqI;		// 0 unless it is an info request or a reply to an info request
	byte	SubT;		// subtype, from SMALL_ enumeration (e.g. SMALL_SSP)

	unsigned	UVal;	// value (e.g. for SMALL_SSP this would be the OutSim packet rate)
};

Packet Details

Size

The size of the packet, always 8 bytes.

Type

The packet type from the ISP_ enumeration, always ISP_SMALL.

ReqI

ReqI must be set to non-zero when sending a request for information to LFS, and in turn the replying packet will contain the same value set in its ReqI. For packets sent by LFS without a request, ReqI is zero.

SubT

The packet's sub-type, which is a value from the SMALL_ enum.

• SMALL_NONE: Not used
• SMALL_SSP: Request to start sending OutSim packets at the specified interval
• SMALL_SSG: Request to start sending OutGauge packets at the specified interval
• SMALL_VTA: Send to set the current vote action, from the VOTE_ enumeration
• SMALL_TMS: Send in single-player mode to stop time, 1 means to stop and 0 to carry on. This freezes the game but is not the same as pausing, as the game must be unfrozen before any further actions can be undertaken
• SMALL_STP: Send when frozen to update the game time by the specified hundredths
• SMALL_RTP: Sent in response to an IS_TINY with a SubT of TINY_GTH. Contains the time in ms.
• SMALL_NLI: Send to set the IS_NLP/IS_MCI interval
• SMALL_ALC: Send to set allowed cars; sent in reply to IS_TINY TINY_ALC.
• SMALL_LCS: Send to set the local car's switches; sent in reply to IS_TINY TINY_LCS.
• SMALL_LCL: Send to set the local car's lights; sent in reply to IS_TINY TINY_LCL.
• SMALL_AII: Send to request a local AI car's info.

Note: SMALL_TMS and SMALL_STP are currently not available in LFS 0.8B/InSim 10.

UVal

A general purpose 4-byte unsigned integer, the meaning of which varies depending on SubT.