Features
Graphics
- OpenGL based renderer
- Dynamic ambient occlusion (corner shadowing) for world surfaces
- Dynamic lights with halos and lens flares
- Dynamic shadowing effects for world objects
- Dedicated particle physics effects system
- 3D models for world objects (with per-vertex lighting and multiple light sources), skies, skyboxes and particles
- Automatical world surface (light) decorations
- Detail texturing, shine and glowing effects for world surfaces
- Fogging and vignette effects
- Environmental mapping effects for 3D models and world surfaces
- World movement smoothing (actors, monsters, missiles, surfaces) to remove the original games' limitation of 35 FPS
- Smart texture filtering using a modified hq2x algorithm
Resources
- Flexible containers: WAD, ZIP, native directory (any resource can be loaded from any container type)
- High-resolution textures: PNG, JPG, TGA, PCX
- 3D models: MD2, DMD with LOD support
- External music files in MP3 and other formats
- Plain text definitions that all share the same syntax
- Internal BSP builder (originally based on glBSP)
Audio
- Plugin based driver architecture: FMOD Ex, DirectSound, FluidSynth, OpenAL, SDL_mixer, Windows Multimedia
- Red Book CD audio playback
- MIDI playback with SF2 soundfonts
- 3D sound stage for positional effects
- Environmental echo and reverb effects (EAX 2.0)
- Runtime sound effect resampling to 22/44 KHz with 8/16 bits
Networking
- TCP-based client/server networking
- Automatical discovery of servers running on the local network
- Central master server for discovery of servers across the world
- Standalone lightweight server (a daemon process)
- Standalone Doomsday Shell tool for server management (both local and remote)
Multiplayer
- Clients can join games in progress
- In-game chat and server management (shell-login)
- Up to 15 player games
- Player movement prediction/smoothing
User Interface
- Graphical command console and task bar
- Easy to use game selection screen for runtime game changing (e.g., from DOOM to Heretic)
- On-the-fly add-on resource loading
- Flexible input control bindings system
- Built-in updater for easy upgrades
Other
- Open source
- Cross-platform
- Plugin based extensible architecture
- Snowberry: GUI frontend based on game profiles; for managing custom maps, resource packs, add-ons and starting different game configurations easily