Author Topic: 3d shakey at range  (Read 1537 times)

Offline Hemlos

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3d shakey at range
« on: 2009-Dec-01 »
3d starts shaking after you go further than 32000 in xyz from the center of the world(0,0,0)

ie
x=10
y=32000
z=10

as go further, the shaking oscillates progressively faster proportionally.

at around 32000 the shaking starts(about 1 pixel across screen), and at 100000+ the shaking is about 3 or 4 pixels oscilation across the whole 3d screen.


I dont know if this is a GLBasic bug, or an OpenGL common issue.
Either way, at this point it is something to be careful of, not to stretch too far.

I found this issue by trying to represent a position as 1 foot, and create a rather large world...time for some scaling.
Volume_of_Earth(km^3) = 4/3*3.14*POW(6371.392896,3)

Offline Kitty Hello

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Re: 3d shakey at range
« Reply #1 on: 2009-Dec-01 »
might be a problem, because internally OpenGL uses 32 bit floats.