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line-weight

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  1. Thanks @zoomer That makes sense - but there are a few reasons why it's difficult just to extrude faces in this particular model, which are a bit hard to explain but come down to the fact the viaduct structures each follow a very gradual curve both in plan and in elevation, while the parapets and other things need to follow the same curve but with their walls and other details "vertical" if you see what I mean. As described in other threads a while back, I already had a lot of problems constructing them as truly curved objects, so they have ended up being made by lofting a profile along a segmented path (with the segments hopefully not discernable in the final renderings). This means that the base viaduct objects are faceted ... although I remain a little confused about what the facets actually are (for example, when I extract some of those faces, I end up with something that is not just a simple 3d polygon). Anyway, I have had various problems trying to extract edges and faces, in order to use them to build up parapets (or provide the paths for extrudes-along-paths which are also driving me mad) and I've in some cases done what you suggest, drawing a polygon directly onto a face, to avoid these. It is unfortunate that VW can only tell me that it can't compute something rather than highlighting where the problem is, because if I knew exactly where the problem was I could focus on that and try and redraw that particular part in a different way. But as it is, it seems I have to go through an extremely time-consuming process of testing every single element to find out if it's the one I need to redraw.
  2. It's a bit of victorian railway viaduct in south London. Very tricky to model even when VW isn't throwing its own spanners in the works! In a bit more context -
  3. Yeah, I don't think the lines are the problem, I tried removing them and I think it automatically deselects them when you make the first attempt anyway. However - you seem to be right that the positions of the objects relative to one another is significant. I tried separating them all using the distribute command ... and then it's happy to add everything together in one go. Is there any valid reason why one object's position in relation to another should make an addition impossible to compute? If not, then is this a bug?
  4. Thanks for the reply @Tom W. Hrm, I can't replicate that, but also can't quite see exactly which objects you've moved. You say two objects, but it looks like more than two objects to me? In other words, the two things you've dragged away, are in fact made of two or more objects each - at least, they are when I open the file. The ultimate aim is to make the whole lot into an addition, which I can then subtract things from. I'd rather not make it a generic solid if possible, because it removes the possibility of later edits to the geometry.
  5. If you want to output at 300dpi, you need to set the sheet layer to 300dpi as well, surely? Not 150dpi.
  6. Is anyone able to offer any insight here?
  7. The sheet layers itself also needs to have the DPI set to what you want:
  8. see my edit above - have you checked the resolution settings in the dialogue I've shown, as well as for the sheet layer itself?
  9. That PDF looks to me like it has been exported at 72dpi, not 300. Have you checked that the resolution is correct in this dialogue?
  10. This object is causing me so much trouble that I've virtually rebuilt it from scratch. But now, it won't let me perform an addition as part of this rebuild. With this post I've attached a file with all the components that I want to add together - but it won't allow this, and I can't work out why. Any help much appreciated. wont_add.vwx
  11. This one gradually driving me into an inconsolable rage today. So many possibilities. So few answers.
  12. I've certainly noticed it with Extrude-along-path objects, which simply baffle me as far as the various internal origins and what they relate to are concerned (and the VW help is entirely unhelpful in explaining how they work). So am always ready for weird things to go wrong with them. But in my example file... the furthest back in the history I can go is with the two circular objects which are extrudes. If I copy one of those circles that they are extruded from... it also lands in the wrong place if I paste-in-place outside of the subtraction. Does the problem exist in my example file if you open it in VW2021 @Pat Stanford?
  13. Here you go - You'll notice that it contains some symbols, and might suspect these to be the problem, but I've tried converting them to regular solids and it doesn't solve the problem. I'm wondering whether this is in any way related to the problem I posted in another thread, about things in subtractions/additions moving location, because there seems to be a bit of that going on with this object. failed subtraction.vwx
  14. Am I right to think that an object that's part of a solid subtraction or addition ought to have an absolute position, relative to the drawing origin? In other words, say I draw solid (A) and solid (B). I subtract solid (B) from solid (A), to create a new solid, (A-B). The void in solid (A-B) is obviously in the same position as where solid B was, before I performed the subtraction. Now I edit solid (A-B) - I go into it and move the location of solid (B), and then I exit it, and of course, the void in solid (A-B) has now moved. Now I go back into edit solid (A-B). I don't change anything, I just copy solid B. I exit solid (A-B), and I do a paste-in-place of the copy of solid B. That copy of solid B should appear exactly where the void is, right? And this logic ought to hold, however many solids I subtract and add to each other ..... right? But either I am losing my mind, or some solids I am constructing are not behaving like this. See for example the file attached to this post. It contains a solid subtraction. Edit the solid subtraction. Copy either of the two objects it's made up from, exit it, and do a paste-in-place. When I do this, the pasted-in-place object appears in an offset location. Firstly, can anyone replicate this, and secondly, why is this happening? origin test.vwx
  15. I'm having this problem with another solid now. This time, it's still unhappy even if I copy it into a fresh file. Any hints to troubleshoot what's causing the problem?
  16. It strikes me that what I really want to do is use a section surface like this to cut the solid: I have drawn that in 2d polys using working planes - there are 3 polygons each on a different plane but their edges meet. What I don't know is how to make them into something that I can use as a solid section. I can convert those polygons into NURBs curves or 3d polygons, but I can't then see how to compose them into one surface (the compose command doesn't do anything). The VW help page on Solid Sections is not very helpful - doesn't tell me anything about what kind of surfaces I can use, whether they can be made up of multiple planes, etc.
  17. Thanks for the response @Pat Stanford So, I managed to get the solid I wanted in my first post. In fact, it seems possible to do it slightly differently than your suggestion: I can extract a surface from each side; VW will not let me use the loft command on these but if I convert them to 3d polys, then back to NURBs (why is this?), then it will, and I can use the "no rail" mode. This gives me a solid that I can subtract, which cleanly removes a section of the wall, but not the parapet. So I can get this far: But you have lost me a bit in the second part of your description - what do you mean I should use to do the solid section - this needs to be a surface, no? What I tried was to set the working plane to the "cut end" of the wall, and draw a 2d polygon: Converting this to NURBs gave me something that the solid section command would not let me use, but converting it to a 3d polygon worked. One thing I am unclear about - what's the difference between a NURBs surface and a NURBs curve, and what's the proper way to convert one to the other?
  18. ... perhaps I should add some context to this question. The solid I'm trying to create above, is one that I want to use to subtract from the larger solid shown in this post (and in teh attached file). Essentially I want to cleanly slice off a portion of the parapet wall, above the level of the highlighted red line. This seems very tricky to achieve. Doing a subtraction is one approach but there may be other better ones. You may need to look at the file itself to understand the geometry here as it's not as simple as it may appear (it's not just a straight extrusion). vsolid.vwx
  19. Never quite sure what the best way to approach this sort of thing is. In this case, I have 8 NURBS surfaces which I've extracted from an existing solid. 2 chains of 4 connected surfaces, and essentially I want to fill in the space between them to make a solid. (None of those surfaces are coplanar, nor are they rectangular) So, the red lines I've indicated would be some of the new edges on that solid. What's the most efficient way of doing this? surfaces.vwx
  20. Advantage of "compose" over connect-combine is where you have a whole lot of segments you want to compose into one line: highlight them all, compose, job done (if it works). With connect-combine there would be quite a few more clicks.
  21. Thanks! This is a tool I under-use. I'll make an effort to explore it some more as you suggest.
  22. I often have trouble getting NURBS curves to compose with other objects such as lines. The VW documentation suggests that this is supposed to be possible - but is it? By way of example the attached file has two NURBS curves which I'd like to compose together with a line that joins their endpoints, but I can't make it work. compose.vwx
  23. yes - this is in 2018. There aren't any fillets or chamfers, no. The symbol consists of two solids: an extrude, and a tapered extrude. Subtracted from this symbol is an addition of two extrudes. It is in fact possible to subtract solids from a 3d Symbol - this was somewhat to my surprise.
  24. What causes this? I have one file where a particular solid fails to regenerate each time I need to recover it from a backup. I can copy and paste this solid from an earlier version of the file - and pastes in fine - it's there and correct, but if I try to do anything to it, even just double-clicking into the subtraction without changing anything, I can't then exit it without it failing. If I copy and paste this same object into a blank file, there doesn't seem to be a problem. There only seems to be a problem when I put this particular object in a particular file. Is there any way I can fix this? Does it indicate a corruption in the file that I should be worried about? It's a subtraction where some simple solids are subtracted from a 3d symbol.
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