Brendan Ryan wrote:
> Apache wrote:
>> 7.4.5 Focal blur hexgrid constants
>> Hex_Blur1 = 7
>> Hex_Blur2 = 19
>> Hex_Blur3 = 37
>>
>> I have two questions about this:
>> 1. What are they used for?
>> 2. I'd like to know how I might calculate Hex_blur4, Hex_blur5 etc
>> etc 3. When using focal blur, does blur_samples 8 look worse
>> blur_samples 7?
>>
>
> I don't know what they are, but I used my TI-86 to find that the
> points (1,7), (2,19) and (3,37) fit on the curve y = 3x^2 + 3x + 1
> where x would be the x in Hex_Blurx and y would be the constants.
> According to the above equation, Hex_Blur4 would be 61, Hex_Blur5
> would be 91 and Hex_Blur6 would be 127.

Thinking about what hexgrid might mean points in the direction that this
equation is correct. (Monospace font needed to correctly view the ASCII
art below.)

 * *
* * *  X=1, Y=7
 * *

  * * *
 * * * *
* * * * *  X=2, Y=19
 * * * *
  * * *

   * * * *
  * * * * *
 * * * * * *
* * * * * * *  X=3, Y=37
 * * * * * *
  * * * * *
   * * * *

Try making bigger ones, and you'll see that they fit the equation
perfectly...

Rune
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rune|vision:  http://runevision.com **updated Jul 25**
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