Ok here is a quick way to get UVs from ray-triangle intersection point:


A;B;C vectors of triangle vertices
P intersection vector
uA uB uC- U coords of A B C
vA vB vC -V coords of A B C

First, you compute distances from P to A, B and C:

dA = distance from A to P
dB = distance from B to P
dC = distance from C to B

sum = dA + dB + dC
coefA = dA / sum
coefB = dB / sum
coefC = dC / sum

So, the texture coordinate at point P is :

uP = uA * coefA + uB * coefB + uC * coefC
vP = vA * coefA + vB * coefB + vC * coefC

Read it in one of 3d math forums ,have not tested yet. But it is expressed
exactly as barycentric formulas are formulated in math.
Good Luck :))

On Tue, Nov 23, 2010 at 2:23 PM, Michael Iv <[email protected]> wrote:

> You should transform these coords to barycentric . I am too stuffed to
> write a showcase on this.But there is a lot of materia on this in the
> web.Also Ask Fabrice he told once he is a barycentric GURU :))
>
> But it seems to me that transform material should contain such an example
> as it projects texture based on vector.
>
>
> On Tue, Nov 23, 2010 at 2:19 PM, John Brookes <[email protected]>wrote:
>
>> Nice.
>> So whats the UV position of the hit ;)
>>
>>
>
>
> --
> Michael Ivanov ,Programmer
> Neurotech Solutions Ltd.
> Flex|Air |3D|Unity|
> www.neurotechresearch.com
> http://blog.alladvanced.net
> http://www.meetup.com/GO3D-Games-Opensource-3D/
> Tel:054-4962254
> [email protected]
> [email protected]
>
>


-- 
Michael Ivanov ,Programmer
Neurotech Solutions Ltd.
Flex|Air |3D|Unity|
www.neurotechresearch.com
http://blog.alladvanced.net
http://www.meetup.com/GO3D-Games-Opensource-3D/
Tel:054-4962254
[email protected]
[email protected]

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