Anti-aliasing problems when Modeling Corrugated metal siding with multiple small radius curved surfaces

My system: Sketchup-pro 2021 running under MacOS Monterey on a high performance Apple desktop i9 Intel CPU with 64gigs RAM and an AMD graphics card with 8gigs vRAM. External 4k monitor.

Seeing awful anti-aliasing problems when modeling corrugated metal exterior siding for an affordable housing project. Created a common residential metal siding component: sinusoidal 7/8" tall corrugations 2.67" ctc. Each corrugated metal panel has (14) pairs of parallel convolutions, a peak and a trough, so there are a fair number of hidden geometry lines (12 each) defining each approx 1/2" radius curve on the metal panel.

Problem is the metal siding surface looks fine when viewed closeup (camera less than 20ft from component surface). The further the camera zooms away from the metal siding the worse it looks because the image becomes filled with extra white lines and moire fringe patterns. Moving the camera to a different angle relative to the surface (normal) can improve or degrade the image.

This is very unfortunate, because the house surface is dominated by corrugated metal siding and from a modest distance (70ft) it makes the model almost unrecognizable in a jumbled mess of thousands of extraneous white lines and interference patterns. I would be grateful for any suggestions which might at least improve the rendered image.

What I’ve tried so far: changed the properties of the metal siding (12) hidden geometry lines that define the curved 1/2" radius areas so the “soft” and “smooth” attributes are disabled. Toggle the visibility property so the (12) lines that make up one of the curves are not visible". This makes no improvement in the image, which is still awful.

Sketchup → Preferences → OpenGL : disable “Use Fast Feedback”, set Anti-Aliasing = 8x (highest setting my video card offers). No improvement in the image rendered from greater than approx 20’ft away from corrugated metal surface.

Generated two screenshots which display the anti-aliasing problem from approx 70’ft away from metal siding surface and a much better image from 20’ft away. However, cant’ upload these small JPEGs to the topic. Can not upload a .SKP file of just the corrugated metal siding component either. Get the “Sorry, there was an error uploading that file. Please try again.” Can any admins help me understand how to upload either a small JPEG or a Sketchup model .SKP file to this forum ?

The geometry you describe is pretty small when viewed from a distance. You might try creating an image of the corrugation, making a material texture with it, and painting flat faces instead of actually modeling the ripples. Depending on lighting you might need a few images to get realistic self-shadow effects.

If it is under 16Mb you can just drag it in a reply.
If bigger, upload to Dropbox or similar, make sure it’s set to public and share the link in a reply here…

Yes the geometry is pretty small compared to the viewing distance.

Thank you for your suggestion. I will try making a texture and use that, hopefully it can be applied over the existing geometry because I need it for sizing to fit other parts in the affordable housing design.

Thank you for quick response.

I tried dragging my 178k jpeg file from my desktop into a reply edit box like the one used now to send this reply, but it give me the same popup error message:

“Sorry, there was an error uploading that file. Please try again”.

Willing to try another suggestion. Very Strange.

Can you share the model using wetransfer, google drive or any other platform?

Yes, I have a Dropbox account, but I worried that would be inconvenient for the forum members to receive the file. The UPLOAD icon on the toolbar above the “Reply” box is the tool I have tried which gives me the error message while using Firefox as the browser. Seems like that should work, however I will try using Google Chrome browser instead to Firefox browser to test if Chrome works any better.


OK - Google Chrome Browser works to upload the two JPEG files illustrating my jagged rendering issue.

Firefox Browser, latest version gives the upload error message. I believe Firefox still has approx 20% market share, so some of us forum members are still using it. Firefox extensions provide ad-free Youtube viewing and the ability to save an entire webpage with media quickly so I use it more often than Google Chrome.

Anyway thanks for the encouragement to keep trying other file upload strategies. I will use Google Chrome on the forum when I need to upload files in the future

A little late to the party. But looking at the pics you posted raises the question did you model the panels with thickness or just a single plane ?