Standing seam cladding rendering

[Theo D]

Hello everyone,

 

I'd like to apply a texture (to which I've applied a relief using a black and white image) of standing seam cladding.

But when I do this and activate the relief, the standing seams come out as I want them to but the flat part of the cladding sinks into the wall.

I'd like only the standing seams to come out without altering the flat part of the cladding.

I've tried to create my displacement map in Photoshop by tracing only the standing seams and exporting it as a png (without background), but nothing works.

 

Is there a solution (other than geometrically shaping my cladding as I need to work quickly and placing a texture is much quicker once it's been properly sized and saved)?

 

Thanks for your help!

[grant_PD]

Can you post an image of what you are trying to do so we can take a look?

[Tom W.]

Ideally post a file

[BartHays]

I don't have time to test this right now but you might try making your flat metal 50% gray and the standing seams, white.

I feel like there was a "feature" where VW displacement maps allow positive and negative displacement.

 

Update: verified.

The image on the left uses a displacement from 50% gray to white, all displacement is above the top plane of the extrude.

The image on the right uses the same displacement map but is mapped from black to white. Values darker than 50% gray recede into the surface of the extrude. 

 

 

Edited August 29 by BartHays

[rDesign]

6 hours ago, Theo D said:

I've tried to create my displacement map in Photoshop by tracing only the standing seams and exporting it as a png (without background), but nothing works.

 

Without seeing images, I'd suspect that how you made your displacement map is the issue. It sounds like you only made a texture with ribs (white?) and nothing for the panels (no background).

 

See the attached sample of a displacement map -- it may be more 'corrugated' than the 'standing seam' you're looking for -- but it should give you the idea. I wouldn't have the image as black and white as you describe, but shades of grey. Save it as a greyscale PNG.

 

Edited August 29 by rDesign

[jmcewen]

Also you don't need to leave Vectorworks to fix your image.  You can do a relatively simple edit like this in the bump edit menus by just moving the sliders to change exposure, contrast, highlights, shadows, etc.

[Jonathan Pickup]

the technique you need to use is to create a bump map where black is the high part and white is the Low part. Here is my image of my bump map and here's the image of my roof with the texture applied. 

[Jonathan Pickup]

but this is how I actually modelled it.

 

 

[rDesign]

@Jonathan Pickup - looking at the screenshot you posted (highlighted section below) it looks like the ribs are receding into the surface, which is the opposite of standing seam.
 

Correct me if I’m wrong, but I believe in a proper displacement map — the white parts project from the surface, while the black parts recede into the surface (opposite of what you described).
 

 

The user manual should really offer more guidance on these types of things than it does. It only says what a displacement map can do, but does not say how to properly create or use one.

Edited August 30 by rDesign

[cberg]

Maybe a different approach.... The AEC Roof Framer tool is an alternate way to model standing seam roof.  I find playing around with RW textures somewhat hit or miss, and the results usually look a little flatter than I would like.  Set the framing to .25" x 1" (6mm x 25mm) and move to the top of the roof face. 

 

[Theo D]

22 hours ago, BartHays said:

The image on the left uses a displacement from 50% gray to white, all displacement is above the top plane of the extrude.

The image on the right uses the same displacement map but is mapped from black to white. Values darker than 50% gray recede into the surface of the extrude

thank you, these are exactly the settings I'm looking for!
However, where is the % displacement setting?
I can find a value but not in % 

[Theo D]

18 minutes ago, rDesign said:

Correct me if I’m wrong, but I believe in a proper displacement map — the white parts project from the surface, while the black parts recede into the surface (opposite of what you described).

that's it.
But what's the right level of grey so that it doesn't go into the surface?

[BartHays]

1 hour ago, Theo D said:

that's it.
But what's the right level of grey so that it doesn't go into the surface?

I used an image editor, to create the bump map, fill an area with 50% grey, and then create the vertical "bars" in pure white.

for proper scaling, imagine that the Texture is 24" square (or some other easy to use real-world size) and build the standing seams at the correct width and separation.

In Vectorworks, create a texture, use whatever you need  for the Color, and set the texture size to  24" ( or to fit your image) 

Use the new image as a bump map, and set Displacement to the height of your seams. 

 

NOTE: per @Jonathan Pickup when I did this, the Image preview in the Texture dialog showed the displacement in reverse, however, the rendering came out correctly, I'm not 100% sure what is going on here,(but it can be flipped by inverting the bump image(see arrow) depending on your results)

 

 

 

[Jeff Prince]

2 hours ago, Theo D said:

that's it.
But what's the right level of grey so that it doesn't go into the surface?

 

50% grey, which is RGB 128,128,128 when using black as negative and white as positive in standard displacement mapping

 

 

49 minutes ago, BartHays said:

NOTE: per @Jonathan Pickup when I did this, the Image preview in the Texture dialog showed the displacement in reverse, however, the rendering came out correctly, I'm not 100% sure what is going on here,(but it can be flipped by inverting the bump image(see arrow) depending on your results)

 

This is likely due to the Normals of your surface being reversed.  It's really important to make sure all of your surfaces are pointing in the correct direction because inverting the bump map could fix one while it messes up others using the same texture.  Fortunately, most things can be flipped in the OIP.

 

Side note, did you know you can make your standing seam by drawing it in Vectorworks instead of a photo editor?  Sometimes this is a lot easier since you are dealing in real world dimensions.  Also helpful if you have complicated patterns, like stamped metal ceilings.  To do it, you lay it out in a design layer in real size, draw a rectangle around it to use as a viewport, and then stick it on a sheet layer for publishing directly to PNG.

Edited August 30 by Jeff Prince

[rDesign]

40 minutes ago, BartHays said:

the Image preview in the Texture dialog showed the displacement in reverse, however, the rendering came out correctly, I'm not 100% sure what is going on here

 

I think the RW texture preview with the Plane Object Type is incorrectly showing the backside of the planar surface -- because when you use a Sphere or Cube instead of a Plane for the preview Object Type, you get the 'ribs' pointing the correct direction.

 

You should not invert the bump map based on what you see in the preview because that would then have the ribs receding into the surface.

 

 

These are all the same displacement texture settings, just different preview object types. The first two look correct, but the Plane looks incorrect, but it is not.

 

Attached is the displacement map I made for this texture and a close up of the viewport. [Displacement maps really do slow down the rendering speed, reminds me why I use them so rarely].

[rDesign]

2 hours ago, rDesign said:

I think the RW texture preview with the Plane Object Type is incorrectly showing the backside of the planar surface -- because when you use a Sphere or Cube instead of a Plane for the preview Object Type, you get the 'ribs' pointing the correct direction.

@Dave Donley - do you know why in the RW Texture Preview when using a Plane Object type and a Displacement Map, it appears that the preview is showing the backside of the preview Plane as the Displacement is inverted? (see THIS post). The Displacement appears correctly when switching to a Sphere or Cube Object Type preview. Perhaps the Normals on the Plane object are reversed?

 

I don't know if it has always been this way, but this is how it appears in Vw2024 -- and it feels like a bug. Thanks.

[Jeff Prince]

32 minutes ago, rDesign said:

I don't know if it has always been this way, but this is how it appears in Vw2024

 

It's been that way for as long as I've been using the program, 2017ish.  I asked the same question a couple of times and got a few different answers.

 

Comically, several in tech support said I built my displacement map incorrectly and that Black was up and white was down, LOL.

I don't think they care to fix these idiosyncrasies, they seem to persist forever.

[Theo D]

Thank you all very much,
I needed to set up my relief maps better and understand the principle behind them better!

Now, another tuning question no doubt: do you know why my standing seam texture, correctly set up, has graphical bugs when I render in the viewport (in optimal rendering)?

Edited September 3 by Theo D

[BartHays]

Can you post the maps? or a VW file with just that texture?

We can do a better job of diagnosing. 

 

From the looks of it, your Bump has variations that look OK in greyscale but cause issues when converted to 3D

 

Bart

[Theo D]

14 hours ago, BartHays said:

Can you post the maps? or a VW file with just that texture?

Here's my bump card.
I just used a solid colour for the colour, no card.

 

(the part with the graphics bug is in a shadow area, could that be where it came from?)

Edited September 4 by Theo D

[BartHays]

Hmm, 

 

The Map looks ok, I tried crushing the levels in PS, looking for irregularities but it looks fine. 

My next guess would be that the Displacement mapping in VW is working with low-res geometry.

you might try upping the Displacement Quality.

 

IF you can't find the error, you might be better off just modeling the standing seams in 3D. 

[Theo D]

29 minutes ago, BartHays said:

Hmm, 

 

The Map looks ok, I tried crushing the levels in PS, looking for irregularities but it looks fine. 

My next guess would be that the Displacement mapping in VW is working with low-res geometry.

you might try upping the Displacement Quality.

 

IF you can't find the error, you might be better off just modeling the standing seams in 3D. 

I've already maximised the quality of the relief and the rendering style...
I don't know what the problem is

[Jeff Prince]

1 hour ago, BartHays said:

IF you can't find the error, you might be better off just modeling the standing seams in 3D. 

 

This is probably best due to the processing time required for displacement mapping vs actual modeling.

[jmcewen]

22 minutes ago, Jeff Prince said:

 

This is probably best due to the processing time required for displacement mapping vs actual modeling.

You could even make an array of symbols so you only need to model one or 2 repeats.

[Tom W.]

@Kevin K did a nice standing seam roof using surface array not sure if this was the thread I'm not seeing the images any more...: