Half-Life resources

 The High Definition Pack spawned from the canceled Sega Dreamcast version of Half-Life, in which Blue Shift was included as a bonus addition to the game. The Dreamcast port boasted improved graphical content, and these models were eventually carried over to the PC after the game's cancellation. However, they were evidently not directly converted as the models that appeared in the Dreamcast port appear to be earlier versions of what would finally comprise the High Definition Pack. The leaked version of the DC game included models that possessed some very noticeable differences from the finished high definition models, and even had some improved models not made part of the High Definition Pack at all. Earlier preview shots of the Dreamcast version shows yet even older incarnations of some of the high definition models.

On August 25, 2005, the High Definition Pack was made available for free through Steam by Valve.However, Valve was criticized for not using the fixed version of the models, which were already available in Gearbox's patch for Blue Shift. These patched models re-included animations missing from the high definition models that, although did not appear in any of the official games, were commonly used in custom levels and modifications. Without these patched models, many modifications will act erratically, as the missing animations can interrupt scripted sequences, possibly preventing the player from continuing or even crashing the game. Many also complained at how the High Definition Pack was implemented in the program. When enabled, Steam automatically disables the use of any other custom content. Over a year later, on August 30, 2006, a staff member of Planet Half-Life released a fixed version of the patched High Definition Pack for use in Steam.