Rendering a CG Scene - An Introduction to Computer Graphics for Artists - page 230

With this in mind, it can be helpful to ask yourself what the story is before you start
to make compositional choices.
For animated compositions, your camera will transition from one composition to
another. During the transition there may be some uninteresting frames, but this can
be mitigated with careful attention to framing and timing of camera movement.

12.6 Conclusion

Lighting is the most important part of any render, but amateurs and students too often
put it last on their list of priorities and accomplish only the destruction of whatever
else they have made. For the best results, keep lighting in mind from the very begin-
ning of your project. Some artists will set up either basic lighting as a fi rst step, or will
make a separate low res stage fi le to test lighting solutions. Whether you plan for it in
the beginning, or simply make a serious effort at the end of a project, if you are sensi-
tive to what good lighting is and make the effort to put that quality into your fi le, your
work will be dramatically improved and taken more seriously by your audience.

12.7 Exercise: Alignment Illusion Part 7

Your alignment illusion project should now be textured and free of modeling errors.
Now it is time to light it and render it. Anyone can put lights in the scene and push
the render button to get a render, but it takes skill to render a scene well. In this case,
you will be asked to practice your composition skills by rendering two images. One
will match the composition of the drawing used as reference, the other will be a
reverse angle that exposes how the illusion is accomplished (Fig. 12.11 ). This com-
position should be interesting to look at and clear. For extra diffi culty, you can use
a motion path to animate the camera moving from the “broken illusion view” to the
fi nal composition.
A special challenge in this project is that lighting will tend to expose the illusion
by causing shadows to be cast in ways that would be impossible if the illusion object
were built as it appears in the drawings. Your goal will be to use lighting to prevent
this from happening. This means that if you try to use a global illumination renderer,
the result will almost certainly give away the illusion. Therefore, you are advised to
use a raytracer for this render.

• Turn off work lights in your fi le and bring in scene lighting. Introduce lights one

at a time, and render the scene after each is introduced. Check the results, make
whatever modifi cations are necessary, and then bring in more lights as needed.

• You will probably have to render your object in separate sections, or attach lights

to specifi c objects. Most renderers will allow you to link a light to an object so
that it is lit but doesn't cast shadows, or it is not rendered but does cast shadows.