[Bf-cycles] build with OSL support
y-fujii at mimosa-pudica.net
Thu Nov 10 04:22:55 CET 2011
Yes, they converge to the same value. however, difffuse() uses
cosine-weighted importance sampler while my oren_nayar() currently
uses uniform sampler, they have different variances. (Sorry for my
poor English skill...)
After night's sleep, I started to think that it is a technical detail,
it can be resolved later when it becomes a problem.
OK, I will change the patch to unify diffuse() and oren_nayar().
On Thu, Nov 10, 2011 at 2:23 AM, Brecht Van Lommel
<brechtvanlommel at pandora.be> wrote:
> I think it should converge to the same result when roughness is zero?
> At least in blender internal this seems to be the case. Also, looking
> at your code: when sigma = 0, we get m_a = 1 and m_b = 0. As a result,
> all that is left is nl/M_PI, i.e. a regular diffuse BSDF?
> On Wed, Nov 9, 2011 at 4:27 PM, Yasuhiro Fujii
> <y-fujii at mimosa-pudica.net> wrote:
>> + Simplify the UI.
>> + Simplify the code.
>> + oren_nayar() and diffuse() have different convergence behavior even
>> if roughness == 0.0, yield very different looks if convergence is not
>> sufficient. In some scene, designers may want to choose oren_nayar()
>> even if roughness == 0.0.
>> + Thus users must know roughness = 0.0 is specialized.
>> I can't decide it because of my poor experience, especially designer's side.
>> What do you think about their cons?
>> On Wed, Nov 9, 2011 at 11:37 PM, Brecht Van Lommel
>> <brechtvanlommel at pandora.be> wrote:
>>> What do you think about implement this as a Roughness input for the
>>> Diffuse BSDF node, instead of a separate one? Internally it can still
>>> be a separate closure/BSDF, but it could just check if(roughness ==
>>> 0.0) diffuse() else oren_nayar().
>>> On Wed, Nov 9, 2011 at 6:55 AM, Yasuhiro Fujii
>>> <y-fujii at mimosa-pudica.net> wrote:
>>>> The O-N patch must be updated, however, the compile errors don't seem
>>>> to be caused by this patch. I guess that they are due to tomato branch
>>>> Blender's source (including cycles) will be changed a lot this week,
>>>> due to a Branch Merger hurricane week:
>>>> I will update the patch when cycles get to be able to compile again.
>>> Bf-cycles mailing list
>>> Bf-cycles at blender.org
>> Bf-cycles mailing list
>> Bf-cycles at blender.org
> Bf-cycles mailing list
> Bf-cycles at blender.org
More information about the Bf-cycles