Multi
Directional Shadow Lighting
He
following exerpt is from the tutorial at http://www.planetside.co.uk/terragen/guide/dlg_light.html#background
“·
Diffuse Sunlight. An "invisible" lightsource which acts from the direction
of the Sunlight, but which has a much "softer" appearance
than Direct Sunlight and does not cast shadows. It can be used
to simulate the lighting effect caused by the bright glow around
the sun in hazy or cloudy scenes. In water scenes, this colour
is reflected in the water as a halo around the sun.
·
Light from Above. An "invisible" lightsource which acts from directly above
the scene. It can be used to simulate the lighting effect caused
by the sky overhead. In early versions of Terragen with water
capabilities, the appearance of the water relies heavily on
this colour.
·
'Reverse Light'. An "invisible" lightsource which acts from the direction
exactly opposite the direction of sunlight. It can be used to
simulate the lighting effect caused by the surrounding landscape.
This lightsource might be particularly useful for lunar, desert
or snowy scenes with bright terrain and dark skies. “ – end
of cite
BUT:
There’s more to it. This is an extremely powerful option for
clouds as well. Always use that one to control how the diverse
types of sunlight impact the scene, and thus the way how the
sunlight colors the clouds as well! Let’s have a closer look
at it:
-
Diffuse Sunlight
Diffuse
sunlight is where the atmosphere concentrates most from your
point of view – the more distant the point you look at, the
more this color takes effect. To illustrate it, I colored this
setting in an ugly red, look at this.
-
Light From Above
Remember,
these settings are all about shadows. So the effect we control
here is, which color the shadows will have, when the shadow
is caused by the light from above. The dark parts of a cloud
are dark, just because they are on the opposite side of the
sun, and this is exactly where the reddish color comes in. Look
at this, same color as above:
-
Reverse Light
What
is this? It looks very much like the picture with “Light from
above” modified to red. The explanation is, that the terrain
itself reflects parts of the visible frequences of light, otherwise
the terrain would be invisible, like a black hole – although
you cannot do this in TG. Now, the terrain reflects light back
to the sky and the color we chose makes the shadows in the clouds
look red. This effect is impacting the scene less directly than
“Light from above”. See also the explanation from the official
Terragen Guide, which basically says, that the source of light
for this setting is coming from the ground.
-
Shadow Lightness
This
slider controls how dark the shadows are, but also, how intense
the colors from the settings below the slider are reflected
in the scene. Try it out, you’ll see what I mean. Decreasing
the shadow lightness greatly helps with the creation of epic
scenes. If you decrease the shadow “lightness”, you actually
make shadows darker. This is also true for shadows in the atmosphere.
Shadows in the atmosphere are casted by the clouds. Look at
this to see what I mean:
So,
this was a more deep discourse into how you could use the parameters
in Terragen to get the type of clouds you want.