3D Software

22/06/00 Update:
succesfully compiled software on NetBSD on the RiscPC.
"Unfortunately the mouse support under svgalib seems to be broken. With the sources from Peter Berg I might fix that."

mmap() of /dev/fb0 under ARMLinux yields compile errors.
"UAfter rereading the man-pages over and over there must be something wrong with my setup of gcc. Loads of libraries seem to be broken.."

how things are hanging:

The current status of the project is:

- can't read VRML since I use a different format for 3d environments.
- written convertor for VRML 1.0 to my own 3d format.
- bitmaps in triangles , 8 bpp with 32 bpp palette or direct 32bpp work.
- shading ( currently flat shaded ) works
- transparancy works ( fixed amounts of alpha)
- 100.000 triangles per second approx. ( needs to be retimed)
- multiple objects with shared memory for manipulation.
- depth sorting for objects is a bit crude.

Introduction:

    The program was written for the Acorn Risc PC quite a while ago. I converted most of the things to the Netwinder but using direct access to the video memory is still a problem.

To solve the graphics problem I reverted to svgalib. Douglas Paul provided the patch for 800x600 in 32 bpp. I revised the plotting routines so that the svgalib does not crash anymore in 32bpp. ( there are quite a few bugs that might be ARM related but to me they look as being general faults.)

why not fix what is broken:

32bpp block copy and bitmap plotting were wrong and I fixed these.
The offset of the blok in put/get_boxpart need an extra x4 for y and x.
The rest of the svgalib is still the same as v.1.3.0 by Douglas Paul.
I tried to fix the clipping errors in the line plotting algorithm but this problem is caused by strange rounding errors.

A fixed version of the svgalib can be found at:
ftp://ftp.netwinder.org/users/j/janrinze/

so where is the thinghy:

A demo of the 3d software can be found there really soon.

Jan Rinze.

june 22nd 2000.