Glidos is a program that emulates the Glide API of the first Voodoo graphic acceleration cards so one can use a modern Windows PC. This way Tomb Raider I - besides other games of that era - can be played in almost the same quality as Tomb Raider II. With the help of high resolution texture packs the quality can be enhanced even further. For a detailed setup instruction see Glidos Web Page.
Please note that savegames made with an unpatched Tomb Raider will most probably not be compatible with a patched version (using any of the available patches for Tomb Raider), and the other way round.
Glidos emulates the old Glide API of the early Voodoo 3D acceleration graphic cards and translates them to ("wraps" them for) modern DirectX or OpenGL function calls. Furthermore newer versions of Glidos come packaged with a DOSBox for 16 bit DOS emulation on modern 64 bit Windows systems that no longer support real mode DOS programmes.
It is possible to play the original Tomb Raider completely inside a DOSBox emulator with Glide support.