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6 Charlie Scanlon (757) 864-2034 LaRC
7 Geotif - geolocation tools for mapping.
8 Dr. Nevan Bryant (818) 354-7236
9 Position Integrity -- Terravoid Bob Servano (714) 854-2643
10 http://www.jpl.nasa.gov/releases/98/damds3.html
12 John G. Watson (818) 354-5011 release 98-52
14 7/22/98 - add some trig debugging wrappers that can be #ifdef'd in
15 kind of like the xgl stuff. The debugging version can do
16 bounds checking and such.
18 6/10/98 - terrain generation - add an option to try to iteratively change
19 the error tolerance to try to generate "close" to a certain
20 number of vertices so that we can have consistent size, rendering
21 speed etc. among various terrain tiles.
23 5/26/98 - Add version checking to scenery files
25 4/25/98 - Roll all of Time/sunpos.cxx into Astro/sun.cxx
27 4/21/98 - Tweak lighting parameter interpolation tables to better fit
30 4/21/98 - Make sure all .hxx files have #ifndef cplusplus #error
31 Make sure all #ifdef _FILE_H or _FILE_HXX
33 4/14/98 - Convert gl__() calls in Cockpit/ to xgl__() calls
35 12/29/97 - Add a mechanism to parse additional command line options?
37 * Less detailed terrain.
38 * Texture - but no MIP-mapping.
39 * Texture - but no bilinear blending.
41 12/29/97 - sky tweaking
43 So, by building the sky in the flattened shape, we can have it be
44 very foggy at the horizon and clear blue overhead.
46 The other important feature of this model is the colours. We
47 colour each vertex of the dish individually to allow for cute
48 sunsets, a darker blue overhead than at the horizon in daylight, a
49 gradual darkening of the sky as a function of altitude for very
50 high altitude flight - into space. Also we tint the horizon more
51 in the direction of the sun so that sunset starts where the sun
52 goes down - and the sky remains blue on the opposite side of the
53 sky - then as the sun gets lower, the colour spreads outwards all
54 around the sky and the black of night creeps in slowly from the
55 opposite side of the sky from the sunset.
57 We also like to tint the bottom edge of the sky with white - even
58 in broad daylight - so it looks fuzzy - even when there is very
59 little fog to achieve that effect.
61 We use a text file that contains a lookup table relating the sun
62 angle relative to the horizon to:
64 * The colour at the top of the sky dome,
65 * The colour of the horizon nearest to the sun
66 * The colour of the horizon farthest from the sun
67 * The colour of the texture environment blend for the clouds.
70 We can then tweak that file to set up all the conditions. The
71 realtime system interpolates the horizon colours all around the edge