From: lioness@maple.circa.ufl.edu
Subject: Kubota vs. E&S Freedome
Organization: Center for Instructional and Research Computing Activities
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Reply-To: LIONESS@ufcc.ufl.edu
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More people have been asking for information on the Kubota graphics
workstations, so here is some more info on the Kenai/Denali vs. the
E&S Freedom.


Here is the text of a Denali vs. E&S Freedom done by D.H. Brown Associates.

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Denali bears a strong resemblance to Evans and Sutherlands Freedom graphics
subsystem in several aspects of its high-level design.  Both products use
a parallel array of 29050 processors for geometric computations.  Both
have a pixel router to connect this front end to a second array of
pixel processors.  As a result, Denali and Freedome overlap significantly
in performance and functionality.  Both design teams also appear to have 
similar philosophies with respect to modularity, scalability, and market
penetration.

There remain, however, several important differences between the KPC and
E&S products.  Evans and Sutherland designed Freedom as a high-end
developer's dream system with plenty of performance potential and
flexibility.  In its favor, Freedom has configurations from two to
sixteen floating point units, a border range that starts and ends at
a higher price and performance levels than Denali.  All Freedom
systems include a large, fixed number of pixel processors that
support a broader variety of color blending functions.  The Freedom
design treats its entire image memory as general-purpose memory, allowing
developers to allocate it on a flexible basis to a number of special-purpose
applications.  Finally, E&S provided Freedom with very flexible otput and
video integration features for multimedia and simulation applications.  Note
that KPC is working an auxiliary board for NTSC and PAL output that will not
require an external video encoder.  E&S programmable output features,
however, will remain much more flexible.

The KPC design team, in contrast, made Denali more of an end-user's system.
Entry version have better performance range and flexibility than low-end
Freedom configurations, and come in at more realistic mainstream price
points.  Denali does not need as many 29050 modules as Freedome because
it uses a deeper scan-conversion pipeline to support each one, resulting
in better cost/performance characteristics.  Although both products provide
strong support for 3D, imaging, and volume rendering, KPC recognized that
not all users will want an even mix of these capabilities.  Denali's
configuration flexibility allows customers in effect to purchase
geometric and pixel processing capabilities separately, and to upgrade
them separately as needed.

Both companies have implemented hardware texture mapping at
workstation price levels as a way to attack SGI's more expensive
VGXT and RealityEngine systems -- the only other products to provide
this capability.  KPC supports point sampling and bilinear interpolation
of textures in hardware, but provides only software support for the higher
qualtiy tri-linear interpolated mipmapping method.  On balance, however, Denali
provideds bettern overall texturing capabilities than E&S for most applications.
Aside from being much more affordable, KPC solutions deliver more parallelism
for texture processing and more off-screen memory for general graphics
data storage.  By implementing texture mapping on its transformation
modules, E&S foces customers to move very quickly to higher price levels
to obtain better texturing performance.  Kubota avoids this problem by linking
texturing to its Frame Buffer Modules, providing a lower-cost, more scalable
solution.

Hope this helps,

Brian

PS This was reprinted without permission.  For the full text, please contact
Kubota 408-727-8100.


