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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 - problem with view culling when not looking forward. Need to
19 generate the correct matrix and work it into the calculations.
21 6/10/98 - terrain generation - add an option to try to iteratively change
22 the error tolerance to try to generate "close" to a certain
23 number of vertices so that we can have consistent size, rendering
24 speed etc. among various terrain tiles.
26 5/26/98 - Add version checking to scenery files
28 4/25/98 - Roll all of Time/sunpos.cxx into Astro/sun.cxx
30 4/21/98 - Tweak lighting parameter interpolation tables to better fit
33 4/21/98 - Make sure all .hxx files have #ifndef cplusplus #error
34 Make sure all #ifdef _FILE_H or _FILE_HXX
36 4/14/98 - Convert gl__() calls in Cockpit/ to xgl__() calls
38 12/29/97 - Add a mechanism to parse additional command line options?
40 * Less detailed terrain.
41 * Texture - but no MIP-mapping.
42 * Texture - but no bilinear blending.
44 12/29/97 - sky tweaking
46 So, by building the sky in the flattened shape, we can have it be
47 very foggy at the horizon and clear blue overhead.
49 The other important feature of this model is the colours. We
50 colour each vertex of the dish individually to allow for cute
51 sunsets, a darker blue overhead than at the horizon in daylight, a
52 gradual darkening of the sky as a function of altitude for very
53 high altitude flight - into space. Also we tint the horizon more
54 in the direction of the sun so that sunset starts where the sun
55 goes down - and the sky remains blue on the opposite side of the
56 sky - then as the sun gets lower, the colour spreads outwards all
57 around the sky and the black of night creeps in slowly from the
58 opposite side of the sky from the sunset.
60 We also like to tint the bottom edge of the sky with white - even
61 in broad daylight - so it looks fuzzy - even when there is very
62 little fog to achieve that effect.
64 We use a text file that contains a lookup table relating the sun
65 angle relative to the horizon to:
67 * The colour at the top of the sky dome,
68 * The colour of the horizon nearest to the sun
69 * The colour of the horizon farthest from the sun
70 * The colour of the texture environment blend for the clouds.
73 We can then tweak that file to set up all the conditions. The
74 realtime system interpolates the horizon colours all around the edge