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Eye
candy:::…
Here’s
some eye candy to wet your taste, enjoy!
Glossary:::…
Here
are some explanations for some of the techniques used earlier
in this preview.
These
explanations were found on the web, so all credits go to
them.
“Every rendering process
consists of two steps. The first is the computing of luminance
values, and the second is the mapping of the computed values
to the values appropriate for displaying on common display
devices. There is a lot of research dealing with the first
step, but the second step is surprisingly often neglected,
although it is far from trivial.”
HDR
HDR
is an acronym for "High dynamic range".
”Now, the benefits of HDR: Normally, lighting is computed
with a minimum value of 0.0, and a maximum of 1.0, which
is multiplied by whatever the colour of the surface or texture
the light is affecting (and don't forget that when you multiply
some variable x by 1, you get x). This only allows for,
in comparison to the real world, a very small range of values.
HDR rendering expands that range GREATLY, enabling values
from 0.0 to some high number (I don't know exactly, but
it's big enough). So you can have surfaces that, with a
strong nearby light, become over-lit.”
Tone mapping
”HDR
rendering by itself is not much though, but there are some
post-processing shader effects that allow HDR to really
strut its stuff. The big ones that people like are light
blooms, glares, and changing exposures. A light bloom is
often seen as light bleeding into other parts of the image,
and glares (e.g. lens flares or lens anomalies) help accentuate
them. Changing exposures (e.g. pupils dilating under bright
light) also enhance the realism.”
“Tone
mapping scales the RGB values of an image, which might be
too bright or too dark to be displayed.
This is done by finding the tonal range of the output
image which is based on the scene’s “key value” or “neutral
value”. The log-average luminance is calculated which is
used as the key of the scene.
The image is then scaled using this log-average and
alpha. Alpha determines the brightness or darkness of the
image.”
Find
more info about HDR and tone mapping here,
here
and here.
Parallax Mapping
Parallax
mapping is a 2D effect that simulates the parallax effects
on bumpy surfaces, giving them a more 3D appearance. This
is done by shifting texture coordinates on a per-pixel basis.
Read about it here.
Cel Shading
Cel-Shading
is the "art" of rendering objects to look like
cartoons.
More
info on it here.
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