Replacing triangles in a part

[griff]

Taking some time to play with avatars again ... run into a little problem. Maybe there is a simple answer that I just missed ;-)

I have created a series of parts for avatars, constructed a smls file, created hierarchy, added shape files to the different parts, set centres ... so far so good.

Now i want to replace some of the geometry (lets say add a thigh part which has some additional skirt geometry). So I delete triangles from part and then add new set of triangles (import new shape file). But now it goes wrong

You can see what happens here :

www.3dworlds.ca/seamless/part_delete.jpg

The new triangles are displaced upwards ... I suspect because the centre has been set. In the example you see I actually am trying to add the *same* part back.

Is there any way around this ... as i would like to mix and match parts that are created to fit together


griff

[thyme]

hi griff

thanks much for posting the problem you encountered here

To verify I just opened Petra into seamless

stoped all animation by un-checking the loop fields for timer1 and walkTs

clicked on the button to reset all rotation values in all the parts

right clicked on the part in the scene tree named l_hip (her left thigh) and selected "export/Shape to file" and saved it with the file name l_hip.wrl

went to the main menu (the f10 menu) and selected "delete/all triangles in part"

then to import the triangles back from the exported file:

right clicked on the part named l_hip again and selected import/Shape from file

selected the file named l_hip.wrl and clicked open

All looks right with the pivot point in the right place

I have seen problems like you have encountered though else where but think it has always been when using build nodes. I am wondering if you are using any build nodes to centre the parts?

If so things can be done to fix this too, if you are happy to do so please send me your file you are importing to and object you are importing and I should be able to quickly see what the issue is.

happy to hear you have been playing avatars

regards

thyme

[thyme]

thanks griff for sending me your files I can now see exactly what the problem is. Like as you suspected in your email the centre for your thigh has been modified (I presume by another program) and is the issue.
If you import your wrl for the thigh by right clicking on the scene node and selecting:

paste/children/import/nodes from file

you see the imported thigh as a VRML Shape node below the Seamless node
If you then convert this Shape node to a Seamless node by right clicking on the Shape node and selecting:

convertToSeamless

the thigh will be seen in the 3d window in exactly the same place as the thigh from the original Seamless node above. This can be verified by hiding the thigh in the seamless node above.
However when you select the thigh from the new Seamless node below you can see the pivot point will be right of the foot instead of at the top of the thigh like the original.

In seamless terms its as if the translation for your thigh has been compile transformed meaning that the thigh is located in the same location as before but has been translated "statically" by the value of the translation field (the vertices have been modified and now the translation field is 0 0 0) as opposed to it being translated "dynamically" by the translation field.

Not sure if I have explained this using common terms and concepts so if I don't seem to be making much sense please don't hesitate to ask further questions so that I can explain things differently.

thyme

[griff]

It worked fine thyme. Only trouble is it highlited another problem I face now

As I have transferred ownership of vetices from part below (the rcalf) when i delete triangles from rthigh it takes *all* of them including the ones transferred to it. Therefore .... you get a gap

That's not seamless problem ... that is mine. ;-)

By the way .... how do i copy the new triangles that have been converted to seamless to the rthigh in the hierarchy

ty as always ...

griff:)

[thyme]

Good to hear it worked fine griff

Yes there are a few other things to watch out for like which part will own what triangle at the borders of the parts. I have learnt to be careful when joining parts using immediate editing techniques like this, to not let triangles over lap each other where they are to be joined because its easy to accumulate lots of hidden triangles without realising it. Back in the days when I made Petra I experienced the problem of one part robbing vertices from its neighbour after using the join close vertices command between 2 parts. This was to do with the order of which part should have been copied and which part should have been pasted to but I am happy to say this problem is now in the past because seamless now prevents the user from doing this in the wrong order. With a little time you should be able to develop a system where its easy to mix and match different parts.

As a result of today playing about with seamless's pivot point and verifying things related, I can see that Seamless does not immediately update the yellow dot to show the location of pivot point when the translation field is changed and or if a compile transform is performed like it should. I am not sure if you will encounter this problem with what you are doing but thought its worth mentioning because this can be quite misleading if you do, had me baffled for a while I will fix this for the next version but in the mean time its easy to update the display of a pivot point after such an action by clicking on a vertex. (holding down the control key while doing this prevents your self accidentally dragging the vertex).

By the way .... how do I copy the new triangles that have been converted to seamless to the rthigh in the hierarchy

I would typically import triangles from a wrl straight into a part using the method of right clicking on the part node and selecting import however it is possible to copy triangles from one part to another even when the parts don't belong to the same Seamless node (at least with the current version 2.092 it worked for me) by doing the following:

right click on the source part and select copy
select the destination part
from the F10 menu select "paste/part"

You can see in the same menu its also possible to copy parts in mirrored form. If the texture mapping is identical for the right and left leg using "paste part mirrorX" can save a lot of time. It is also possible to cut parts like the torso or head in half so that you only have half the model to edit. The opposite side can be created back by copying the edited side and pasting the copied triangles back to the same part using "add paste part mirrorX"
This technique and other things related is shown in the tutorial "Making an Avatar from Immediate Spheres and Cylinders" on the page:

www.seamless3d.com/tut/immediate_av/joining_mid_parts.html#JoinNeck

thyme

[thyme]

If you want to centre the new triangles for the thigh (which are centred right of the foot base) before copying them and pasting them into the rthigh above so that the thigh is centred the same as the original, you can move the pivot points using the buttons from the toolbar until the translation field matches the translation field for the rthigh above. (this must be done before copying and pasting the new triangles into the rthigh above)

Alternatively the same results can be achieved by the following procedure:

copy the value of the translation field from the rthigh above and paste it into the translation field for the part that contains the new triangles.
invert (make positive negative and make negative positive) the x y and z components of the translation field for this part that contains the new triangles
While this part is selected, from the F10 menu select "compileTransform/scale/rotation/translation
Although the thigh will have moved down and the pivot point is now at 0 0 0 the pivot point will be shown at the top of the thigh (if not control click on a vertex to update the display of the pivot point)
now all you have to do is copy the triangles how I explained in the previous post to the destination part above and you will see the new triangles located and centred like the original thigh.

thyme