To add the final three colors bring up the surfaces dialog box again and add a second instance
of IFWLinear to the object. Set all of the parameters the same as the first IFWLinear except for
the blends points and the colors.|
Now for a bit of explanation. What we want to try and achieve is to blend the last color of the
first IFWLinear texture, i.e. green, with the first color of the second IFWLinear texture, which
is Cyan. Now, the way we will achieve this is to create a alpha blend and use layering to
allow the first IFWLinear texture's colors to show through. Hopefully, this will make sense
once you see the settings. First of all, set the four colors as Cyan, Cyan, Blue and Violet.
Notice that the Cyan is added twice. This is so the first color can be made clear using the
alpha channel. Next set the blend points as B1=42%, B2=56%, B3=70% and B4=84%.
The last thing that is required is to control the alpha channel and layering so that the
last color of the first IFWLinear texture blends nicely into the first color of the second
IFWLinear. This is done by setting the first alpha point to 100% and checking the
Layer enabling check box. The important point is that the underlying color, the first
rainbow colors, are unaffected until the texture function reaches the 42% blend point.
Here, the second IFWLinear is blended in going from clear cyan to opaque cyan.
This creates a nice blend from the underlying color, green to new color cyan which
is exactly what we want to achieve.
The Complete Rainbow