[REQ] Lock texture coordinates

[Whaat]

Here are some methods to load and save UV sets. If someone wants to use them to create a 'lock texture' plugin, that's fine with me.

def store_uvs(ents,uvset)

face=0
case uvset
	when 0
		key="uv0"
	when 1
		key="uv1"
	when 2
		key="uv2"
	when 3
		key="uv3"
end

Sketchup.active_model.start_operation "Save UV set"

for e in ents
	
	if (e.valid?) and (e.class==Sketchup;;Face)
		
		polymesh=e.mesh 5
		uvs=polymesh.uvs 5
		for i in (0..uvs.length-1)
			uvs[i]=uvs[i].to_a  #converts the Point 3D objects to arrays so they won't be transformed
		end
		e.set_attribute 'uvs',key,uvs
	
	face=face+1
	Sketchup.set_status_text("Stored uvs for #{face} faces.")
	end
		
end

UI.messagebox "UVs saved for #{face} faces."

Sketchup.active_model.commit_operation

end #function

###################position a texture on a material from a stored UV set
def position_map(entities,set)

face=0
failed=0
return if set=="SU"  
key="uv"+set.to_s
p "positioning map"
p entities
for e in entities
	p e
	if (e.valid?) and (e.class==Sketchup;;Face)
		
		uvs=e.get_attribute 'uvs',key    #gets the stored array of uv coordinates for this face for the given uv set
		p uvs
		if uvs
			pos=[]
			polymesh=e.mesh 5   #get a polygon mesh representation of the face
			polygons=polymesh.polygons  
			poly_index=0
			begin
				for p in polygons[poly_index]
					point=polymesh.point_at(p.abs)
					if point
						pos.push(point) 
						pos.push(uvs[p.abs-1])
					end
				end

				e.position_material e.material, pos, true
				face=face+1
				Sketchup.set_status_text("Loaded uvs for #{face} faces")
			rescue  #this is required because SketchUp sometimes fails to position the texture properly
				poly_index=poly_index+1
				if polygons[poly_index]
					pos=[]
					retry  #try to postion texture again using next polygon in the face
				else
					failed=failed+1
				end
			end
	
			
		end
	end
end

if failed>0
	stext="Unable to load
	UVs for #{failed} faces.  Loaded UVs for #{face} faces."
else
	stext="Loaded UVs for #{face} faces."
end

#UI.messagebox (stext)


end  #end position map

[dacad]

WOW, thanks Whaat. Has always you're great!:)
My knowledge in ruby is very limited so can anyone help with this? (or change the name of this topic to "[Request]Lock texture coordinates")
Thanks in advance

[remus]

Unfortunately it isnt quite as easy as that. Ruby has it's own separate commands that dont necessarily match those that you see in the SU UI.

I suppose you could think of it as ruby seeing a different UI to what the user sees: sometimes the stuff we see matches up with what ruby sees, sometimes ruby sees extra stuff we dont see and sometimes we see stuff ruby doesnt see.

[Jackson]

I was going to post a request/enquiry regarding this precise issue when I found this post. What baffles me is that this can already be done per individual face via the left click texture position editor (Right click on face>Texture>Position>Enter) which is fine for cuboids, but is pretty much useless when working on large triangulated meshes.

As it's already possible on a per face basis in SU is it not relatively simple to write a ruby which simply repeats this action on all selected faces? Easy for me to say seeing as am and most likely always will be completely useless at programming, but Matthieu Noblet's "Components to Groups" script got me thinking. In principle it does almost exactly what we want- allows you to select geometry/groups/components, then performs a series of right click actions upon it/them. In that case it is:

Select Component>Explode>Group>Deselect>Select Next Component>Explode, Group,... etc.

Could the same principle (or even some of the same code) not be applied to this problem so you select a mesh, and the ruby then starts the sequence: Select Face>Texture (i.e. Open Texture Editor)> Position>Enter>Select Next Face,... etc?

I've had a look in Matthieu's C2G code, but like I said, even basic ruby is beyond me. Matthieu's a very generous guy who I'm sure if requested would be willing to allow someone to edit and redistribute parts of it for a good cause. This ability, combined with all the recent "organic" modelling ruby scripts would be incredibly useful for SU users like myself who would rather keep 3D Max and Rhino OUT of their workflow!

I understand of course (or at least I think I do) that SU has major UV mapping shortfalls- as I understand it, if you stretch/deform a face in SU elasticly, there's no way for SU to stretch the texture accordingly so edges still tile with adjacent faces (though that does make me wonder how Whaat's UV Spherical Mapping tool works?), but even an automation of the current Texture>Position>Enter would be of enormous benefit.

p.s. guess who just spent 2 days texturing a tree!

[thomthom]

@jackson said:

I was going to post a request/enquiry regarding this precise issue when I found this post. What baffles me is that this can already be done per individual face via the left click texture position editor (Right click on face>Texture>Position>Enter) which is fine for cuboids,

That doesn't lock anything. If you map a texture to a face (quad - or whatever - doesn't matter) and do the Position trick - then when you move an edge or vertex the texture doesn't stick with it.

I wonder if you're asking for something else..?

[Jackson]

Tom,

That's what I said at the end- it doesn't stick the texture to the vertices or edges, but it does stick the texture to the face. Once you've hit Enter you can move or rotate the unedited face about as much as you want and the texture will stay in place- i.e. SU seems to create a new UV coordinates plane which is fixed coplanar to the face. In this way the texture stays fixed until you edit the vertices or edges at which point the texture "moves" or rather the texture actually stays fixed on the face's UV plane while the faces geometry floats around on it. Like I said, it wouldn't be SU's answer to pelt or shrink mapping, but each face having its own UV coordinates plane would still be an enormous help in SU.

[remus]

Doesnt that happen anyway? i.e. without the right click->position texture thing.

[Gaieus]

If you don't position the texture on the face,it will be positioned to the world axes. If you start moving the face around, you can see the texture "move" relative to the face but "stick" absolute to the WAxes. This can be "fixed" by positioning the texture on the face but it won't get really stuck to it but as Jackson says, it will stick to another "plane" that is "positioned" to the face itself, not the WAxes.

Still if you start editing any vertex (say just start moving an edge), the texture won't follow but remain on this "invisible plane".

Hard to explain something hat only virtually exists and maybe is not even so just I make up these "synonyms" to explain what I experience.

[remus]

I see what you mean, i'd never noticed that before, for some reason

[Gaieus]

Well, it's not apparent until you encounter a certain case...