walstad@ocean.UUCP (Leonard J. Walstad) (12/29/86)
We are considering the GPX as a graphics workstation. As a fluid modelling
group a large number of graphics images are produced daily. Each
image generally contains approximately 100K vectors. We wish to add
color and produce images more quickly and are wondering about the
capabilities of the GPX.
1. At what speed are vectors drawn by the GPX? (How was this measured?)
2. What transformations are done in hardware? Rotation,Scaling,etc.
3. Are namelists supported?
4. Shading and 3-D are not supported?
5. Software support? (GKS, highlevel packages)
Obviously, these questions have been asked of DEC reps. They have not
been able to supply the answers with any detail and have not gotten back
to us. Any information which you can supply would be most appreciated.
Comparisons with other machines are particularly encouraged. Please
let me know your application so that I can compare with our needs.
Note that an Iris or similar machine would be great, however we are
trying to supply several GPX's for individuals and then maybe an Iris
for group use. I will summarize to anyone interested.
Thanks, Leonard Walstad walstad@harvard.harvard.edu
Pierce Hall G2H
Harvard University
Cambridge, MA 02138
617-495-4128cetron%utah-ced@UTAH-CS.ARPA (Ed Cetron) (01/08/87)
sorry for the delay, I took off for winter vacation and its has taken a week to catch up..... we have one GPX running vms and I love it (so far...) 1. At what speed are vectors drawn by the GPX? (How was this measured?) fast, but what slows things down is not the drawing speed per se, but the speed at which the display list (in vax memory space) can be updated, with 100k vectors, this can slow significantly, and modifying the display list can take forever. You CAN turn of the display list for animation, but you then lose the capability to move objects, transform objects, repaint the screen etc... 2. What transformations are done in hardware? Rotation,Scaling,etc. I recall that move region (as distinct from move object), rotate region and scale region 3. Are namelists supported? not sure exactly what you mean... display lists are... 4. Shading and 3-D are not supported? nope - big lose.....I am writing my own 3-d and shading stuff now. 5. Software support? (GKS, highlevel packages) gks is supported as are several language interfaces (X-windows and UIS) Let me know if you have any more questions. -ed cetron Univ of Utah cetron@ced.utah.edu or cetron%utah-ced@utah-cs.arpa