Engine

This parser works with demo files from the GoldSrc engine — the game engine powering early Valve titles.

Supported Games

Game	Demo extension
Half-Life 1	.dem
Counter-Strike 1.6	.dem
Team Fortress Classic	.dem
Day of Defeat	.dem
Any GoldSrc-based mod	.dem

HLTV vs POV Demos

The parser supports both types of demo files:

• HLTV demo — recorded by an HLTV (Half-Life TV) proxy server. The filename typically contains a timestamp pattern (-ymdHi-), which the parser uses to extract startTime.
• POV (Point of View) demo — recorded locally by a player using the record command. These files usually do not have a timestamp in the filename, so getStartTime() returns null.

Demo File Structure

A .dem file consists of:

1. Header — 8-byte magic sequence HLDEMO, followed by demo protocol version (offset 8), network protocol version (offset 12), map name (offset 16), game directory (offset 276), map CRC (offset 536), and directory offset (offset 540).
2. Entry table — array of directory entries, each 92 bytes:
   • Entry number (4), title string (64), flags (4), CD track (4), track time (4), frame count (4), data offset (4), data length (4)
3. Data segments — each entry points to a segment containing sequential macro blocks:
   • Loading segment — map signon data with server messages, terminated by a LAST_IN_SEGMENT marker.
   • Playback segment — recorded gameplay frames with network update messages.

The parser extracts all entries and their metadata (type, description, flags, CD track, track time, frames, offset, file length).
For LOADING entries, the parser additionally parses the macro block headers (DemoFrame[]) from the data segment.
PLAYBACK frame parsing requires the full HLTV network protocol and is not implemented.