In the mid to late 1990's, many visuals systems integrators began to review PC-based Image Generator (PC-IG) technology in earnest. Driven largely by the entertainment industry, CGI technology has made impressive strides over the past five years with PC graphics card performance in areas such as pixel fill rate and polygon processing capacity reaching the levels achieved from a comparable graphics channel of a SGI Onyx2 or E&S ESIG.
Experienced visuals systems integrators will be primarily concerned with protecting their investment in databases and application software so that the ability to port these easily to the PC-IG is of paramount concern. If an application can be ported, then IG upgrade and replacement paths will become available along with the attendant cost benefits to the user that are inherent in the introduction of lower cost PC-IG technology.
There are many factors that affect how well existing visual/sensor databases and run-time special effects software will run on a PC-IG. In addition, different visuals applications, for example, in land, flight, naval, or civil simulators, can each bring a new set of porting problems.
Key aspects for porting are ·
the equivalence between the existing Graphics Application Programming Interface (API) used in the software to be ported and the one selected for the PC-IG ·
the level of application support provided by the API ·
the degree of completeness, or variation from the standard, of the graphics library implementation (eg OpenGL) ·
support for sensor simulation, overlays, and special effects ·
terrain management and texture handling ·
interface considerations
The paper describes AMS's experience in porting to several different IG platforms with different APIs and highlights the lessons to be learned. It also discusses issues relating to image quality such as anti-aliasing and texture implementation.