4 ms·
AutoCAD for DOS shipped at some point with a cool NASA Space Shuttle demo, I remember seeing it render (can't remember if on a 286 or 386) without a co-processo
by achairapart 3y ago
AutoCAD for DOS shipped at some point with a cool NASA Space Shuttle demo, I remember seeing it render (can't remember if on a 286 or 386) without a co-processor and it took several minutes, as each line slowly rendered on screen.
The same demo with the same machine now equipped with a co-processor, it took just a few seconds.
As a kid, I knew nothing about FPU nor math co-processors but that incredible speed bump had a long lasting impression on me.
- Animats 3y agoAutoCAD was supposed to require a math co-processor, but there were software co-processor emulators available which could, slowly, do floating point. That's probably what you saw. AutoCAD was 64-bit floating point (and sometimes 80-bit internally). Trying to do 80-bit floating point computations on a 16-bit CPU was painfully slow. Previous low-end CAD systems were 32-bit, and large drawings would have errors. That's why the Golden Gate Bridge drawing was a common AutoCAD demo. Zoomed out, you could see the whole bridge, and you could zoom in on the details. Big selling point. (I did some of the early AutoCAD ports. Not all DOS machines were fully compatible with the IBM PC. There were many 80286 machines which were mostly-compatible. Each needed its own software. Every display, mouse, and plotter needed its own driver. Autodesk had a big room in Sausalito with one each of everything they supported. For a while, it looked like the Texas Instruments TI-Pro was going to win, because it had a color display good enough for text. But it was an awful computer. No memory parity and bad parts. I had to compile everything twice and compare the results.)