Che Tamahori
...thought
identityactionthoughtplace

newly shocked

>


this movie requires shockwave 6.0

fake alpha channels

Drag the images around the movie window to the left. Note the nice smooth text edges on the top image, and smooth alpha transition. This is the sort of thing that is almost impossible to do without alpha channel support.

What's going on here? Alpha channels in Director? Without AlphaMania? Well, almost. This is an example of how nicely anti-aliased (or even alpha-channeled) images can be placed over other images without "pixel rot".

The secret is to use two different versions of the upper image. One of these is pre-blended with a background of the predominant colour of the lower image. Here's an example. I want to place a smooth-edged blue circle over a red circle... all on a white background. Just to make life hell, I'll blur one half of the blue circle's edge.

To make this work, I use the following castmembers:

load me! load me! load me!

The first and last cast members make sense -- but the secret is in the middle cast member. Import the images into your cast, and make sure that the two "blue" circles have the same registration point. Now place them on the stage in the following channels:

  1. The red circle in whatever ink mode you want,
  2. The middle cast member (blue on red) is in lightest mode,
  3. And the last cast member (blue on white) is in darkest ink mode.
That's it. I've made the sprites moveable, and given Sprite 2 the following handler:

on prepareframe me
  set the loc of sprite 2 = the loc of sprite 3
end

This just ensures that the two blue circles stay together. The result is shown below.


this movie requires shockwave 6.0

home / thought / shockwaved ideas / newly shocked < > NEW Fake Alpha Channels - 57 kb

> Metaballs - 8 kb

> 3d Polygons - 9 kb

> Reflection - 30 kb

> magnification - 19 kb

> the DNA of shockwave design - 14 kb

> rtf anti-aliasing - 10 kb






c o n t a c t   m e  :  c h e @ s f x . c o . n z