Integration and Implementation

Integration of DirectMusic Technology

DirectMusic functionality had already been a part of the LithTech engine, so integration of the technology was already complete. We innovated in the area of AI, however. NOLF already integrated an advanced state machine, which calculates the player's state and enemy AI. The programmers simply made it possible to trigger music states via game states. These game state to music state associations were made in the LithTech level editor so that different game levels could have unique setups if desired. The level editor also allowed two or more music states to be assigned to one game state, one of which would be randomly chosen during run time. The most intense music states, 5 and 6, were both assigned to the combat game state. Also, music states 1 (silence) and 2 (sub-ambient) often shared the quiet "investigate" game state. Assigning multiple music states to a single game state cut down the repetition and predictability of music within a given level by adding variety to game scenarios.

Implementation of the Music Content

The adaptive music state machine described above makes implementing the DirectMusic content easy. The first steps include checking the DirectMusic files into the game and properly setting up each game level. The LithTech level editor selects the music theme and script for a given game level. The music themes are thus assigned to the various levels, each theme being used across an average of three or four levels. Ninety percent of the music's adaptability is handled by the state machine. Location-based triggers account for the other ten percent and override the state machine when triggered. Location-based triggers come into play when a specific theme or music state is desired, regardless of the game state.

NOLF cinematics apply the same themes and music sets as the adaptive game score. Music triggers are placed at key points in a cinematic, where music is needed, and transitions between music states automatically occur. Triggering music states from cinematics works surprisingly well but certainly does not sound as good as custom cinematic scores. Music scored specifically to a scene matches the events more precisely than music composed out of context. The adaptive music sets and triggers are used because the NOLF cinematics were not complete in time to score them individually. The lesson is to reserve production time to custom score game cinematics and demand that the developer finalize the timing of them before the scoring begins.