Hi there,

What is the meaning of the Att variable in method "compute_lighted_texture"?
It is computed
using the fomula
Att = (1.0 - (LayCol[pFILTER]*max3(LayCol[0],LayCol[1],LayCol[2]) +
LayCol[pTRANSM]));

Thanks,

Jing

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Jing Li wrote:
> What is the meaning of the Att variable in method "compute_lighted_texture"?
> It is computed
> using the fomula
> Att = (1.0 - (LayCol[pFILTER]*max3(LayCol[0],LayCol[1],LayCol[2]) +
> LayCol[pTRANSM]));

Attenuation.

	Thorsten

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Could you tell me what kind of attenuation of Att is, such as Light-source
attenusation or Atmospheric attenuation, and where the original formula
comes from?

Thanks,

Jing

Thorsten Froehlich <tho### [at] trfde> wrote:
> Jing Li wrote:
> > What is the meaning of the Att variable in method "compute_lighted_texture"?
> > It is computed
> > using the fomula
> > Att = (1.0 - (LayCol[pFILTER]*max3(LayCol[0],LayCol[1],LayCol[2]) +
> > LayCol[pTRANSM]));
>
> Attenuation.
>
>  Thorsten

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Jing Li wrote:
> Could you tell me what kind of attenuation of Att is, such as Light-source
> attenusation or Atmospheric attenuation, and where the original formula
> comes from?

1. Learn to quote, please.
2. Read your own text...
 the function is compute_lighted_texture, so what do you believe is
happening there ?
Att is a scalar coefficient used to dim the texture... now consider what
pFilter and pTransmit might reference, and try to draw the relevant curves.
Then look where Att is used (just a few lines after the one you cited)

the only caveat I would have about the filter mechanism is that a
texture which filter must have the same reflecting color... that's part
of the used data-design, and it is not always practical.

> Thorsten Froehlich <tho### [at] trfde> wrote:
> 
>>Jing Li wrote:
>>
>>>What is the meaning of the Att variable in method "compute_lighted_texture"?
>>>It is computed
>>>using the fomula
>>>Att = (1.0 - (LayCol[pFILTER]*max3(LayCol[0],LayCol[1],LayCol[2]) +
>>>LayCol[pTRANSM]));
>>
>>Attenuation.
>>
>> Thorsten



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