John VanSickle wrote:

> (Stuff on MPEG compression)

What to Y, U, and V stand for, anyways?

> You can see this on TV; whenever there is a bright red object on the 
> screen, you'll see that the edge of the redness tends to stray from the 
> edge of the object.

You especially see it on older screens with the color, contrast, or 
brightness knob turned up too high.


> If your Beziers are quadratic, and you go for heavy math lifting, there 
> is a formula that will tell you exactly how long a given section of the 
> spline is.  Shockwave Flash files use strictly quadratic splines, with 
> good results; you need twice as many splines, but the math is so much 
> easier that it pays off.
> 
> For cubic splines, my method was to move the spline's sampling point an 
> educated-guess distance along, check the actual distance, and adjust the 
> sampling point by the discrepancy between the actual distance and the 
> desired distance, and repeat until I got close enough not to make a 
> difference to the viewer (within .1 mm is good enough for the ties on a 
> roller coaster, methinks).

This page has the formulas used for calculating the beziers:

http://www.moshplant.com/direct-or/bezier/math.html

> As for saving the locations to a text file, you could have the POV-Ray 
> SDL write all of the data to an .INC file in SDL (with all the #declare 
> and other statements), and then invoke that .INC file.

I always forget about .INC files and the fact that I can write my own 
using SDL.

-DJ

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