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Hi all,

Recently I dove into LDPC and need some help.
Questions I have:

1. Can I use primitives in patterns?
2. Can I select more then one primitive and copy/paste/duplicate them?
3. Can I group a primitives and triangles and copy/paste/duplicate them?
4. Can I use submodels in patterns?

For example, I am creating the pattern for the laserrelector sticker from set 10266.
It has a repetative pattern of dots.
I made one dot with disc primitives and filled the gaps with triangles.
Now I want to use that dot as many times as needed, create the rows and copy them.

Attached is my work so far.

Thanks.
(2019-06-14, 11:58)Jaco van der Molen Wrote: [ -> ]Hi all,

Recently I dove into LDPC and need some help.
Questions I have:

1. Can I use primitives in patterns?
2. Can I select more then one primitive and copy/paste/duplicate them?
3. Can I group a primitives and triangles and copy/paste/duplicate them?
4. Can I use submodels in patterns?

For example, I am creating the pattern for the laserrelector sticker from set 10266.
It has a repetative pattern of dots.
I made one dot with disc primitives and filled the gaps with triangles.
Now I want to use that dot as many times as needed, create the rows and copy them.

Attached is my work so far.

Thanks.

1. Yes ( When using disc prim then always use a ndis prim to) 
2. No
3. I don't know 
4. Yes
(2019-06-14, 11:58)Jaco van der Molen Wrote: [ -> ]1. Can I use primitives in patterns?
2. Can I select more then one primitive and copy/paste/duplicate them?
3. Can I group a primitives and triangles and copy/paste/duplicate them?
4. Can I use submodels in patterns?
1. Yes, though often it's not worth the trouble. Use primitives only if you can use matching primitives/negative primitives otherwise you'll have troubles with primitive substitution where primitives and soup of triangles meet. Here you should use a 1-4ring1 primitive for the lower right black ring (and you could possibly use a 3-4disc primitive instead of 3 x 1-4disc).
2. Unfortunately no, which makes this a mess to do. I'd probably use LDPE for that since it doesn't have this kind of restriction (LDPE also allows to make multiple translations/duplications at once which is very powerful here!
3. No you can't. once you select a primitive, all other selections are forgotten.
4. We are supposed to be able to do so (file -> import from dat -> append as subpart) but it doesn't seem to work exactly as I would expect (rotated subparts)... perhaps someone else has more experience with this?
OK, here is the plan:

[attachment=3748]

To make a dot the green, blue, red and white 1-4disc prims are uses.
Yellow is 1-4ring1.
The other yellow thing is the ndis prim.

I'd like to make a sumodel for that (the dot) or is that a bit overdone?

Grey (for now) are just a bunch of triangles. I am unsure how to fill the gaps yet, but probably triangles and rectangles.

The corners are round so the sticker would have round egdes too.
(2019-06-14, 12:26)Philippe Hurbain Wrote: [ -> ]1. Yes, though often it's not worth the trouble. Use primitives only if you can use matching primitives/negative primitives otherwise you'll have troubles with primitive substitution where primitives and soup of triangles meet. Here you should use a 1-4ring1 primitive for the lower right black ring (and you could possibly use a 3-4disc primitive instead of 3 x 1-4disc).
2. Unfortunately no, which makes this a mess to do. I'd probably use LDPE for that since it doesn't have this kind of restriction (LDPE also allows to make multiple translations/duplications at once which is very powerful here!
3. No you can't. once you select a primitive, all other selections are forgotten.
4. We are supposed to be able to do so (file -> import from dat -> append as subpart) but it doesn't seem to work exactly as I would expect (rotated subparts)... perhaps someone else has more experience with this?

Ah yes there is a 3-4disc too! Big Grin
(2019-06-14, 12:35)Jaco van der Molen Wrote: [ -> ]I'd like to make a sumodel for that (the dot) or is that a bit overdone?
Imho yes, it's overdone...
Quote:Grey (for now) are just a bunch of triangles. I am unsure how to fill the gaps yet, but probably triangles and rectangles.
LDPC knows only about triangles. But when exporting to dat, adjacent triangles are automatically converted to quads.
Quote:The corners are round so the sticker would have round egdes too.
BTW, using 1-4chrd instead of 1-4disc is better there (less vertices).
Did you find the Group/Ungroup buttons yet?

As Philo said, LDPC only knows triangles.
With Group/Ungroup it is easy to Copy "primitives" but only if you Ungroup the primitives first.

Select Primitive mode.
Select the primitive you want to split.
Click on Ungroup.

I have done this, and coloured every triangle in the ungrouped primitive. One colour for each uniqe primitive in my pattern.
When I'm satisfied with a section of the pattern, select every wanted triangle in the pattern, use Group, set the origin of that group, (I often use  the center of the sticker I'm working on, 0 , 0 ) and then it is possible to multiply the pattern by copying that group of triangles.

After an export it is possible to replace all triangles in a specific colour with the wanted primitive, if you want to do that.

I find the Group/Ungroup to be useful in this kind of repetitive patterns.
(2019-06-14, 16:24)Magnus Forsberg Wrote: [ -> ]Did you find the Group/Ungroup buttons yet?

As Philo said, LDPC only knows triangles.
With Group/Ungroup it is easy to Copy "primitives" but only if you Ungroup the primitives first.

Select Primitive mode.
Select the primitive you want to split.
Click on Ungroup.

I have done this, and coloured every triangle in the ungrouped primitive. One colour for each uniqe primitive in my pattern.
When I'm satisfied with a section of the pattern, select every wanted triangle in the pattern, use Group, set the origin of that group, (I often use  the center of the sticker I'm working on, 0 , 0 ) and then it is possible to multiply the pattern by copying that group of triangles.

After an export it is possible to replace all triangles in a specific colour with the wanted primitive, if you want to do that.

I find the Group/Ungroup to be useful in this kind of repetitive patterns.

OK, so if you ungroup a primitive, it will "break" into triangles?
And triangles export to quads if possible.

Thanks for these tips too!
(2019-06-15, 6:38)Jaco van der Molen Wrote: [ -> ]OK, so if you ungroup a primitive, it will "break" into triangles?

Yes, that's right.
So I have the pattern ready.
And I "borrowed" the thin box (0.25 LDU thick) with round corners from this part 4216816a.dat and modified it to fit a 2x2 area.
Now the BFC is not right, and I have no clue on how to fix that.
Can someone take a look? File is attached.
LMKWYT
(2019-06-15, 18:25)Jaco van der Molen Wrote: [ -> ]So I have the pattern ready.
And I "borrowed" the thin box (0.25 LDU thick) with round corners from this part 4216816a.dat and modified it to fit a 2x2 area.
Now the BFC is not right, and I have no clue on how to fix that.
Can someone take a look? File is attached.
LMKWYT

Should now be BFC correct.
Rounded to 3 digits.