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duplicate shells to simulate rough metal
Dear scjo has started a very difficult and important topic here . How to get rough metal in SH3D. The mirrored prefixes in the OBJ file make the surfaces smooth, polished, mirrored. It is very good for chrome-plated plumbing items. But how do I get unpolished items? There are a huge number of them, but the program does not make it possible to make a rough texture and get truthful renderings of such metal. I started experimenting with duplicate shells that can change the sharp reflections from mirrored surfaces. I made a group of round holes in the wall with the help of windows. The result is a module that can be copied and assembled into large groups (walls or shelves with holes). exported to OBJ. Back as a model. I made a copy with invisible windows and exported it again. Here in the MTL file I assigned transparency d 0.1. And increased the thickness by 1 mm. I got a mirror perforated wall with a mirror prefix in OBJ and a duplicate exactly the same transparent model, but without a mirror prefix. If you combine these two models, they will complement each other. Now you need to assign a TEXTURE to the mirror color model of the transparent duplicate. If you assign a color, you will get glass. The texture gives a cloudy translucent shell on top of the mirror. Now you can influence the sharp reflection.
the first render is some kind of dark JPG texture for the outer shell. The color of the mirror model almost does not matter, a light shade of metal is obtained under the outer shell, which is very slightly distinguishable. The color of the mirror gives a picturesque rendering, you can give any shade other than the surrounding background. I have assigned a pink one)). Because the sky is blue.
it is very important that all the surfaces of the outer shell do not overlap in any way and do not coincide with the mirror surfaces. I made a mistake, the cylindrical surfaces of the holes match, so defective places (sometimes, not always) appear on tenders. You need to make smaller holes (windows in my case) for the outer shell, then there will be no bugs. to get spectacular soft highlights, I highlighted the edges of the outer shell with 6% hemispheres. This gave the effect of a shiny metal edge. This glare itself will not appear in any way, it must be done on purpose.
the next render is more complex. I took the texture of porcelain stoneware with black crumbs on a white background and cleaned out the entire white background in Photoshop, saved it in PNG. Assigned this texture to the transparent shell. Interestingly, the PNG texture canceled the transparency setting of this model. Black cats have become opaque black, with transparent gaps. This needs to be taken into account. The PNG image assigns its own orders as a texture. The mirror surface of the lower model is visible between the black crumbs. And the reflections are more colored. The brightness and sharpness of these reflections depend on the density of the crumbs and the size of the gaps between them.
the next render is a porcelain tile with a gray crumb on a white background, I also cleaned the white background in the editor, saved it in PNG. This texture is more correctly placed on the mirror. I softly smoothed out the reflections of the lower mirror, but at the same time there is a feeling of metal texture, there are bumps and irregularities, roughness. I liked this option with a gray texture better.
for comparison, I removed the outer shell, leaving only the pink bottom mirror.
Germany, Berlin
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Re: duplicate shells to simulate rough metal
Amazing! Especially the third last picture, after the stoneware texture, is quite encouraging! The night is too late for me now (after local midnight) to comprehend your explanations right away, though. Would you mind sharing the *.sh3d?
I cannot model the holes other than by texture. One shelf has ~10� of them. Each hole of N-gonal shape causes 4N + 4 additional triangles. To a room with only 5 shelves, even utterly coarse square holes would add one million triangles in total. Now Dodecagon's dodecagon: +2.6 million, without his divider.
For the same reason, physical roughness is not an option. Once I have learned how you achieved the rough look, I will do it the same way, and then add the holes by texturing. Much like the virtually impenetrable mirrors got punctured from an alpha texture by way of compositing.
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Cheers - Joe //
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Re: duplicate shells to simulate rough metal
here is the file holes can be made in three (?) in different ways. 1. windows in the wall 2. Cylinders in the room (it is necessary to somehow save the cylinders as a door, to my shame I did not understand how to apply it to the end (((). 3. You can also draw everything you want in another program and make this drawing as a background image. Start making a room and circle the holes carefully around the perimeter. 4... I tried to place the cylinder doors in the room in the file and nothing worked, and this is the most correct location, everything can be seen immediately on the plan. And you need to make a model with reduced holes for the outer transparent shell!!! (this is important for rendering bugs). I don't have this in my file.
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Re: duplicate shells to simulate rough metal
... I cannot model the holes other than by texture. One shelf has ~10� of them. Each hole of N-gonal shape causes 4N + 4 additional triangles. To a room with only 5 shelves, even utterly coarse square holes would add one million triangles in total. Now Dodecagon's dodecagon: +2.6 million, without his divider.
For the same reason, physical roughness is not an option. ...
As expected for creating roughness but I didn't realize a shelf had such tiny holes, i.e. so many. You can optimize this by making sure shelf and holes are a single group in the obj file. Sweet Home 3D processes by group so that should make a difference. Still, the huge number will make it very slow.
On the other hand, there are many 3D models with (real) perforated metal. A simple search using "perforated" on a site like cgtrader.com shows many great examples and most are under a million polygons. Some I noticed use hexagonal holes but others are cylindric with the correct interior hole sides. This means it is possible but not by creating the holes in Sweet Home 3D. That's something Sweet Home 3D can do but the program is for interior design, not 3D modelling.
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Re: duplicate shells to simulate rough metal
... I tried to place the cylinder doors in the room in the file and nothing worked, ...
sorry, not the cylinders are doors, but the cylinders are stairs (to insert them on the plan into the room)
You can't use cylinders-as-stairs for this. When you import an object and check the staircase box it will import as a staircase but the hole it cuts in the floor is square. It needs a custom cutout which you can't set in the import dialog. You can add the cylinder to a Furniture Library and there you can set a custom cutout.
SVG cutout for a circle:
M 0.5,0.5 l 0.5,0 A 0.5,0.5 1 1,0 0,0.5 A 0.5,0.5 1 1,0 1,0.5 z
For complex cutouts use a window in a wall. For example import a character as a 'door or window' to create a hole with the outline of the character.
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Germany, Berlin
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Re (going OT): duplicate shells to simulate rough metal
Still, the huge number will make it very slow.
... the more with my stubborn graphics. My recent joy of getting the FLE to run lasted only until I realized the price: Inadvertently, I had switched back [sic!] to the current Linux kernel. With that, however nvidia doesn't see my 2nd monitor. That's why I had initially pinned the previous kernel to my system.
Anyway, I decided to sacrify that in favour of FLE. Until I opened blender the next time. In blender, even a mouse klick to any push button takes several seconds(!) for the button to change colour at all.
Blender's GUI is entirely based on OpenGL. I infer, that with graphic normally operational the GUI is done by the GPU, but now with crippled driver functionality the CPU must groan under that load, an 8 years old Core i3 duo.
But nor harm without good: thoughtless resource usage is noticeably penalized - which leads directly to your optimization credo. At the moment, I'm deliberately keeping my system in that condition.
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Cheers - Joe //
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Re: Re (going OT): duplicate shells to simulate rough metal
But nor harm without good: thoughtless resource usage is noticeably penalized - which leads directly to your optimization credo. At the moment, I'm deliberately keeping my system in that condition.
Very wise. I have a pretty new and fast system but I still use my old machine to check if larger projects are workable. My large projects will probably never run on a mobile system but my extreme optimizations ensure the smallest possible individual models.
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: +2.6 million, without his divider.
