Graphics Programs Reference
In-Depth Information
18. Let's go to the
Properties Editor
, locate the
World
tab and set these opions:
F
Ambient Occlusion panel: Disabled (it will be enabled later)
Factor: 1
Blend Mode: Muliply (drop-down menu)
F
Gather panel:
Gather Method: Raytrace (irst row of opions)
Atenuaion Distance: 1
Atenuaion Fallof: Enabled
Atenuaion Fallof Strength: 0.01
Sampling Method: Adapive QMC
Samples: 16
What we are doing here is preparing the seings for Ambient Occlusion, which is a nice
method to add shadowing to the objects in the scene. Seing the
Blend Mode
to
Multiply
causes the shadowed parts to become quite dark, which is what we need. The
Gather
Attenuation
opions are for controlling how wide the shadows will be; since this efect
will only be applied to the mother ship, we use a small distance (the details of the ship
are quite small). The Raytrace method is the one with the best results in terms of shape of
the shadows; the method and samples are set to get soft shadows (a low samples number
will likely cause noise in the rendered shadows). Now, why leave these seings disabled?
(
Ambient Occlusion
panel was left disabled), well, that's because this effect will only need
to be applied for one layer of the scene, not for the whole scene, so we will come back and
turn it on temporarily only when needed.
That's it for the scene creaion; now it's ime to play with the compositor.
Objective Complete - Mini Debriefing
We let for the very end the creaion of the energy shield for the mother ship. This task
requires no modeling, since we use a sphere with some scale values; the actual shield effect
is achieved by means of the shaders. In this case we applied Raytraced transparency (to be
able to use some slight refracion) and worked only on the specular shader for the material.
The trick is about textures and ramps, and geing the efect of the textures afecing the
right channels of the material. The lighing works together with the shading, and we just
created a basic lighing setup to control where the impacts on the shield will be located.
We also prepared a simple
Ambient Occlusion
setup, in order to be ready for the
composiing part of the inal scene.
