Copy Sop Problem

[JesseVFX]

i bind export P parameter as a parameter called Direction and N,but after the copy sop , the Direction is different from N 。Why?
Can i correct it except the right method ?
Did i miss something ?

 

here is an example file below (Houdini 15.0.313)

thanks

Copy Sop Problem.hip

Edited August 1, 2016 by JesseVFX

[benne5]

Hi Jesse,

If I understand your problem correctly I beleive that you want to check on the "Use Template Point Attributes" selection located on the attributes tab of your copy node.

Cheers

 

 

 

[bluciensky]

If you uncheck 'transform using template point attribute' on copy SOP, it will work, but I think that's not the result you want.

This happens when you copy volumes(ex - 'vel' field will be messed up, so that you need to rotate it afterward).

 

 

[cgnema]

Hi Jessie,

 

The reason they are different is because the copy sop is transforming (rotating) the N but not the Direction attribute you created.

When you create a vector attribute with a bind in vops: it makes it a float[3], so if you look in your geo spreadsheet the Direction attribute will show direction[0], direction[1], direction[2]. But N has N[x],N[y],N[z].

The [xzy] indicates that the attribute should be transformed by any operations that do transformations (like the copy sop with "Transform" using template point attributes). The direction however shows [012] so it will not be transformed.

You can fix this with an add attribute node with "Type Info" set accordingly.

attributeTypeInfo.hipnc

[JesseVFX]

13 hours ago, cgnema said:

Hi Jessie,

 

The reason they are different is because the copy sop is transforming (rotating) the N but not the Direction attribute you created.

When you create a vector attribute with a bind in vops: it makes it a float[3], so if you look in your geo spreadsheet the Direction attribute will show direction[0], direction[1], direction[2]. But N has N[x],N[y],N[z].

The [xzy] indicates that the attribute should be transformed by any operations that do transformations (like the copy sop with "Transform" using template point attributes). The direction however shows [012] so it will not be transformed.

You can fix this with an add attribute node with "Type Info" set accordingly.

attributeTypeInfo.hipnc

thank you Nema !!!  that's the problem.

Is that a bug or something ? why I export it as a vector and it will be a 3f ?

[cgnema]

You're welcome! Im really not sure, maybe they wanted to avoid custom attributes being transformed by default.