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- 3-D VIEWER - Version 2.5
- ==========================
-
- August 1991
-
-
- 3DV displays 3-dimensional wire-frame objects or data, with real-time
- rotations. It works on IBM PC/AT compatibles, with VGA, EGA, CGA or
- Hercules graphics. A Microsoft-compatible mouse is required.
-
- This program is made available for unrestricted use. However, it may
- not be sold or included with other software. The package may be
- copied and distributed freely so long as all its files are kept
- together, unmodified, and no remuneration of any kind is received in
- exchange.
-
-
- USAGE
-
- Load the mouse driver before running the program. Data file names
- can be given on the command line (3DV filename.ext), or later with
- the FILE option. Options/commands are selected by clicking a mouse
- button on the appropriate selection boxes. Perspective or orthogonal
- projections can be specified.
-
- 3DV attempts to detect the graphics hardware and sets the default
- mode accordingly (CGA is selected if identification fails).
- WARNING! With some configurations (e.g. EGA without the enhanced
- color monitor) hardware damage can occur if the wrong mode is
- selected. The EGA mode requires a 256k EGA card and enhanced color
- monitor.
-
- The FILE option presents a menu with all the files matching *.3* in
- the current directory. Some samples are included. See below how to
- set up your own data files.
-
- In display mode, the position of the view point on a sphere
- surrounding the object is controlled by moving the mouse:
- horizontally changes the longitude, vertically changes latitude.
- Pressing a button takes you back to the options menu. That's all
- there is to it!
-
-
- DATA FORMAT
-
- Data is given in ASCII text files, in free format, in the following
- order:
-
- number of points
- x, y, and z coordinates for each point (scaling is automatic)
- ...
- number of connecting lines or moves (number of items below)
- point number to draw or to move to, and color (color=0 for move)
- ...
-
- Yes, a bit obscure, but see the sample files for examples.
-
- Capacity is limited by 10*(number of points) + 4*(moves and draws)
- <= 58280 .
-
-
- CHANGES FROM PREVIOUS VERSION (2.0)
-
- - Fixed memory allocation bug, increased capacity.
-
- - New stand-alone Hercules routines. These ones actually work!
-
- - Point-and-shoot file selection.
-
- - Hardware auto-detect.
-
- - Better latitude/longitude display; previously conflicted with
- ANSI.SYS.
-
-
- TECHNICAL INFO, ETC.
-
- After the public release of 2.0, several people asked about the
- source code. Sorry, but after thinking about it I decided not to
- make it available. Among other things, it is not a pretty sight.
- Believe it or not, 3dv originated from a Basic and Z80 Assembler
- version that run on my TRS-80 clone (made in HongKong, yes, they
- invented the clones! BTW, it still works), with a homemade graphics
- card based on the TI TMS9929A chip (256x192 pixels). The port to the
- PC was one of my first uses of C and 8086 Assembler, several years
- ago. Definitely not fit for human consumption.
-
- If you must know, 3dv is written in Turbo C, with fast line drawing
- routines in assembler. Speed is due largely to the use of 16 bit
- integer arithmetic, with careful scaling and arrangement of
- computations to maintain precision while avoiding overflow (as in the
- good old days). Note, however, that absolute precision is a bit
- lower than the display resolution. Uses double buffering, swapping
- between two video pages (except CGA that buffers from RAM). VGA uses
- only the EGA 640x350 mode, which is the highest standard mode with
- two video pages. The performance of buffering in RAM for higher
- resolution modes might or might not be acceptable, and hi-res paging
- may be possible with SVGA, but I have wasted enough of my time
- already. No further versions are planned unless, perhaps, if some
- horrible bug is discovered (or I receive some offer that I can't
- refuse).
-
-
- CREDITS FOR EXAMPLES
-
- SKULL.3D and 2SKULLS.3D - Prehistoric Pacific islands skulls.
- Dr Foss Leach (srgibfl@wnv.dsir.govt.nz), National Museum of New
- Zealand.
-
- TREE1.3D - Pine branch measurements, from crown architecture study.
- Dr David Whitehead (whitehed@mof.govt.nz), Forest Research
- Institute.
-
- GLASS.3D - Stolen from example by Gershon Elber in GNUPLOT (a
- very good plotting package, recommended. Look for
- <MSDOS.PLOT>GPLOT-3D.ZIP in SIMTEL20).
-
- GALAXY.3D - From "A simulated view of the Galaxy" by Mark Dahmke,
- BYTE, April 1979, p 66-80.
-
-
- Send me your favorite 3dv pretty pictures. We could distribute
- collections of them if there is enough interest and contributions.
-
-
- Oscar García (garciao@mof.govt.nz) - 1 Clyde St, Rotorua, New Zealand.
-
-