Layer0 questions

Al Hart

Is Layer0 always the first layer,

e.g. Sketchup.active_model.layers[0].name

Is the name of the default layer always "Layer0" - even in foreign versions?

I guess this could and would change with templates.

Does anyone use a template where Layer0 has a different name?
It looks like you cannot change the name of Layer 0

Sketchup.active_model.layers[0].name = "Test"

does not change the name.
(It does for Layer1)

TIG

Is Layer0 always the first layer,
Layer0 is always listed in the Layer-Browser first even when they are ordered 'alphabetically' or 'reversed' - since it is preexisting logically it ought to be the first in model.layers
e.g. Sketchup.active_model.layers[0].name
Is the name of the default layer always "Layer0" - even in foreign versions?
I guess this could and would change with templates.
**Layer0** is the EN name for **layer==nil**. It has other names in different locales. To find its name set **model.active_layer=nil** and then use **model.active_layer.name**. You can't rename it in a 'template' - it is just based on locale naming for **layer==nil**. You can use the fact that the default-layer is 'nil' and get it's name without knowing the locale or anything else... just set a temp-variable to remember the current **tlay=model.active_layer**, change to 'nil' [**model.active_layer=nil**], then get the **deflayname=active_layer.name** [>>> "Layer0" e.g. depending on the locale], then just reset **model.active_layer=tlay**
Does anyone use a template where Layer0 has a different name?
You can't rename Layer0 in a 'template' - it is just based on locale naming for **layer==nil**. Every non-EN locale user will have their own name for the default-layer...
It looks like you cannot change the name of Layer0
OR its equivalent name in other locales

Sketchup.active_model.layers[0].name = "Test"
does not change the name.
(It does for Layer1)
Correct. Sketchup spots if the layer is 'nil' and assigns the locale's 'default-layer' name to it - in the case of EN-US it's 'Layer0' - it is immutable...

Al Hart

Wonderful answer TIG.

I was about to use this set of code to skip the default layer:


			model.layers.each do |layer|
				# do not process Layer0
				next if layer.name == "Layer0"
				...

However I had better find a different way to skip the first layer,

However in searching for Layer0 in my Ruby code I see a number of other items which sound like they may not work.


				# remember layer name unless it is a pass through
				if (entity.layer.name != "Layer0")
					eparms2.parent_layer = entity.layer.name
				end#if

or

				model.active_layer = model.layers["Layer0"]

The second one can easily be replaced with:

model.active_layer = nil

But the first one seems more troublesome.

This seems a bit cumbersome:


tlay = model.active_layer
model.active_layer = nil
deflayname = active_layer.name
model.active_layer = tlay
if (entity.layer.name != "Layer0")
	eparms2.parent_layer = entity.layer.name
end#if

Do you have a suggestion for seeing if an entity is in the 'nil' layer.

Al Hart

Which layer does model.add("Layer0") return in a foreign language version?
(A new layer or the nil layer?)

I presume the foreign language versions cannot create new layers called Layer0, because that would get confusing if I tried to use the model in English.

Can someone tell me what Layer0 is called in some other language where it is different, so I can see what happens if I try to create a new layer with that name.

TIG

layer=model.add("Layer0") does return a reference to a layer in any locale - including EN.
It is the same layer as model.active_layer=nil
Setting the active layer to nil and getting its name is the foolproof way of finding the default-layer's name in that locale.
If you are sure that layers[0] is always the default layer then using that should work too.
Then to process all layers except the default-layer you can use
model.layers.to_a[1..-1].each{|layer|###do process###}
as it misses off the first one...