It was with dismay that developers
learnt that one of the simplest and most powerful effects that of additive
blending (AB) wasn't built into SW3D. However it was soon established
that with cunning use of texture layers and certain 3d API's it was
possible to achieve the effect. Further effort helped to ascertain
a better understanding of the workaround, but until now there had not
been a guide that really explained it in detail, nor the extensive
testing to ensure the greatest compatibility between 3D cards.
This guide outlines first what is additive blending then the methodology
behind accomplishing the effect in SW3D. It goes on to describe the
Additive Blending Test Demo, results from a wide selection of 3D cards,
systems and API's, a conclusion to the results, questions and answers
to help understand the conclusions, and finally how to let Director
determine by itself the settings required for additive blending (self
diagnosis).
Included
with the guide is the open source
version of the
Additive Blending Test Demo, along with an example
of how to implement the feature within a project.
The first four images illustrate realtime
glow effects augmented through additive blending.
The fifth has the same glow effect, but with trails, and the sixth is just additive
blending. |
