CompuServe Messages

#new PAR.EXE

    11-Oct-94 09:05:17
Sb: #128280-#new PAR.EXE
Fm: Gus Grubba 70673,1605
To: Robert A. Weil 75121,2507
The PXP is just a control panel to access the different settings in the driver down below. The limitation is of PARDRV, not the PXP. The problem of supporting multiple (simultaneous) reads and writes is that the file must be converted in its entirety before sending either way. In other words, when you copy a Targa file over to the PAR, the driver will read the entire file in its buffer. When the copying is done, it will convert to YUV and then send it over to the PAR. If a second read or write request arrives while one is being processed, there is no "second" buffer to load and convert this image. DOS isn't multitasking. If it were, all I had to do was to wait for the first request to finish. Having several buffers is a little impractical as each buffer is at least 1.1 Meg. The only simple solution (simple when compared to almost impossible) is to handle YUV files directly. For that a new driver would have to be written. This driver would know nothing about Targas. Just raw YUV files. That way, no buffers would be needed. The driver would also be much smaller. The draw back is that no software out there knows about YUV files. It would be simple to handle 3D Studio (through a BXP) but that's about it. By the way, this is all up to DPS, not me. I will do whatever they ask me to do (well, almost) but it is very unlikely I will write something of this magnitude "just for fun". So, when you say "I can only hope that Gus will one day modify the PXP…", I can't do anything about it.