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1232 Chapter 15: Lights and Cameras
make the effect g rainier, especia l ly at the edges of
objects. Default=0.4.
Tile Size—Setsthesizeofthepatternusedin
dithering. T his value is a percentage, where 0 is the
smallest tile, and 100 is the largest. Default=32.
Scanline R en derer Params group
These controls let you disable antialiasing or
antialias filtering when you render the multi-pass
scene. Disabling these rendering passes can
improve render time.
These controls apply only to renderings of the
motion blur effect, not to previews in viewports.
Disable Filtering—When on, disables the filtering
pass. Default=off.
Disable Antialiasing—When on, disables
antialiasing. Default=off.
Camera Match Utility
Tools menu > Camera Match
Utilities panel > Utilities rollout > Camera Match button
The Camera Match utilit y uses a bitmap
background photo and five or more special
"CamPoint" objects to create or modif y a camera
so that its position, orientation, and field-of-view
matches that of the ca mera that orig inally created
the photo.
Pr ocedur es
The Camera Matching tutorial takes you through
stepstomatchacameratoabitmapbackground
photo. It’s an involv ed process, but the results are
worth the work. The general process that you
follow in that tutorial is described in the following
procedures.
To use camera matching:
1.
Load a bitmap as a background for the renderer.
2. Load a bitmap as a background for the
view por t.
3. Identify on the bitmap at least five features that
will be used for t he match. These should be
objects or corners of objects in the scene that
can be identified and tracked. They should
remain visually throughout the scene, and
should not change their shape too much or they
won’t work.
4. Create CameraPoints, which are helper objects
found in these locations: Create panel >
Helpers > Camera Match > Object Type rollout
> CamPoint, and Create menu > Helpers >
Camera Point.
You must have accurate measurements of
distances between at least five features in your
scene, which can’t be all on a single plane. Try
to use points that are distributed throughout
the scene rather than features that are all
clustered in the front or back. This will give the
most accurate results.
5. Position these CameraPoints to correspond
to points in your photo. You can use the
Transform Type-In (page 1–412) to position
the points in the correct locations in 3D space.
6. U se the Camera Match utility to assign the
CameraPoints to pixel locations on the bitmap.
7. Choo se Create Camera and a camera is created
to match the one that took the picture.
If there are errors and the camera cannot be
created, readjust the point positions in 3D
space, and reassign them to the bitmap. It’s
easy to make a mistake doing either, but once
you get it right the match should work.
To establish the bitmap ba ck ground for the renderer:
1.
Reset the software and enlarge the Perspective
view por t to full screen.