material cycles preview 2.69

can someone explain how the new material preview works in 2.69 for cycles

now got some

viewport color
multi importance
pass index
transp shadows


Have you been living under a rock recently? :wink: Nothing in here is new except “Transparent Shadows” which is rather recent.

The material preview has been here since 2.65 or 2.66. It works like in Blender Internal. You build your material and the result appears in the little window.

I found it wonderful when it appeared but, now, I see only its shortcomings. First, the UV mapping is crap… Second, the objects are super-tiny. If your objects have a reasonable size… Let’s say over 1x1x1 unit, the scale of the textures in the preview won’t look like anything but like on your objects.

I think the “Viewport Color” has been there since the beginning of Cycles… I think that the name just changed recently.

I use it extensively… as soon as I have at least 2 materials. It allows to have more contrasted colors than just the default greyish white all over your scene. One color per material. Total luxury! :wink: Just don’t use very dark colors or you won’t see your wireframe any more.

“Pass Index” is just the new name for “Material Index”.

“Multiple Importance Sample” is also just a new name for an old option. (I don’t remember the previous name… Nor if it’s exactly the same option.) The tooltip suggests it should be activated for large mesh lights because it will remove some noise.

“Transparent Shadow” as the tooltip suggests should be activated if your material uses the Transparent shader because it will improve the result.

I must that these 2 options are activated by default… and I don’t touch them. “Multiple Importance Sample” used to be deactivated by default… and I’m still trying to find the difference.

If those 2 options do something, it’s either very subtle or I haven’t used them in a situation where they matter. :wink: Let’s just postpone any decision until the words of an expert come to tip the balance one way or the other…

Note that “old”, “recent” and “new” are very relative for me. I live a bit in the future since I update my Blender almost every week from the Build Bot… Sometimes even twice a week if a bug comes in the way of what I’m working on. I’ve always 2 or 3 very recent versions of Blender “installed” so it’s never a problem to delete what I just installed and go back to the previous one while I wait a few days to download a new one. :smiley: (The joy of an unlimited connection…) :wink:

did you see documentation on this and where ?

i did not see any specific notes in the release notes!
but i also know other things changed over time and are not well documented
so it is hard to follow things with cycles!
name ,location even meaning of vars change over time but not well documented

i know that some parts were there
but now i look at it in 2.69 and find things that i did not really saw before
or that where not there
like this pass index i tought it was in the object panel as material index before
but wondering if it is the samething or something new!

just wish there was better documentation
hope other people have better knowledge to clarify the situation!


Documentation? What’s that? :wink:

It’s just because of the speed at which I update my Blender. One blend file often goes through several versions and I notice when something changes… at least in the parts I use. A new name for an option stands out like a sore thumb. :smiley:

And I follow (from a distance) the SVN commits over there:

There’s a lot of techno-mambo-jambo… But, in between, you can find very interesting stuff… In such a case, I download immediately and I test. Like I just saw a button to load images in the UV/Image Editor was added one hour ago. I must see that. :wink:

About the “Pass Index”. There’s a little mix up of names. There is also a “Pass Index” in the Object tab but it’s the formely-known-as “Object Index”… And the 2 options still have their original names “Material Index” and “Object Index” in the “Passes” panel… So, some change is to be expected here again.

so many changes and so little doc
yup what documentation and where is it !

it’s getting difficult to follow all what is happening
but nice to know it is moving fast

just wish there was more consideration for good doc
peoples cannot read mind only doc!LOL

have fun with no doc!
if i had more time i would follow all the sites !

happy cycles