OBD talk:OTLF: Difference between revisions

OBD talk:OTLF (view source)

1,108 bytes added , 27 April 2007

I don't feel comfortable with that 12/20 bit thing.

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 ==> 12/20: Oha... it seems, that they have changed it after Brent Pease has left Bungie. [[User:Ssg|Ssg]] 10:01, 23 April 2007 (CEST)
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+I don't feel comfortable with that 12/20 bit thing. 12 bit, that means a max of 4096 gunk quads per leaf node. That seems a bit to much to me. The GDC-paper says, that 256 is the limit. Did they increased it?
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+Maybe we can look at first 4 bytes of the OTLF packages 15 and 16 (IIRC) of level 3:
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+package 15: 13000000 ==> 12 bit = 130 (hex) = 304 (dez)<BR>
+package 16: 0E300100 ==> 12 bit = 0E3 (hex) = 227 (dez)
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+That's what you get, if you read the 12-bit from right to left. If you calculate the sum of all 12-bits you get 2 million and a bit. Plus the highest 12-bit is 4080, which means 4080 gunk quads in a leaf node. If you read the 12-bit from left to right, the sum ist ~ 3 milllion and the highest value 4081.
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+Maybe they've used the factor four, because a lot of the packages overlap each other. (Dunno if this is really a reason.)
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+If you look to package 16, the 20-bit ist 256 (read from right to left). What does it tell me? Start with package 256 and read 227 packages or start at position 256 and read 227 packages? Or something else?
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+[[User:Ssg|Ssg]] 16:07, 27 April 2007 (CEST)