Hw7 supplement

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Hw7 supplement

• Fall 2004

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R2T (symmetric vehicle)
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2
0

• 180?8 images (180/7?26) apart
• port side
• starboard side
• Reverse the port-side image

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f
4
f
5
6
7
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Capture image as large as possible
x
r
r/sin(q/2)
qfovyAR
z
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Panorama can be
Note that OpenGL has max texture size of 2048
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Or

• 16 rendered frames

256

Glubyte image51220484 2D image array
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Image Array
Glubyte image45 2D image array
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Relative Orientation
billboard
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Impostor

• One special kind of billboard that makes the
  rendered image indistinguishable from the real
  geometry
• Often generated on the fly
• Issue of positioning and sizing
• Regenerate whenever the billboard is no longer
  valid (within the error bound) (due to change of
  viewpoint).
• Most appealing for high framerate, or slow camera
  movement

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Quasi-Impostor

• What we do here is not exactly impostor (hence,
  quasi-)
• Adjust the size of your billboard to fit scene

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Find angle from dir to pxz If positive, portside
else, starboard side Pick the frame accordingly
dir
x
b
pxz
n
v
z
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Compute angles
b
q
a
up 0,0,1
q atan2 (up (a?b), a b)