Posts made by August

August

HOWEVER much this has helped the original poster with their specific problem, it does not yet answer the question stated in the topic title.

I'm here because I'm trying to find where the Ruby Console will load a file from. I thought it would have the same answer, but maybe not in SU2015.

August

An update about 5 years later...

At the link above, to Matt's original announcement of the PDF, is the link to a Google Docs page:
https://drive.google.com/file/d/0B1JtraED8shnNGZkNzM4ZmQtMTVmNS00Zjc4LWI2NjMtYzliZGVjYzQyNTU5/view?ddrp=1%26amp;hl=en#

As of today, that works for me.

I also found the PDF at http://www.crai.archi.fr/rld/pdf/Automatic_SketchUp.pdf

Those help with the fact that http://www.automaticsketchup.com and http://www.autosketuchup.com appear to be redirects to a page with only a link to a legal disclaimer. That's too bad.

As for paper vs PDF, I have the paper book open for reading and I'm using the PDF to be able to do text searches. I can copy the code out of the PDF to past it into the Ruby console. And just like with music, buying the book supports the author where freebies, bootleg or not, do not.

Unfortunately in this case, the book is out of print. You can get a used one for $250.00 on Amazon or a new one for $570.00 to $800.00. Yeah. More for this book than for SU Pro. And I bet not a dime of that gets to the author.

Seems like it's time for an update to the newer versions of SU. The book was published in 2010 for SU 7.1.

Does anyone know how to get hold of Matt Scarpino? I bet this group could do a crowd-sourced update of it pretty quickly.

Just ideas,
August

August

Well, I got here too late for the poll, but I do see that it reached 90 before being closed, not counting those who thumbed-up instead of poll voting. Does that mean it's a go for the non-drab version? Would another vote help?

August

When I was a teen I used to follow Model Railroading and was fascinated by articles that were tutorials on building models like this in brass and motorizing them. This work appears to involve many of the same skills and passions, without requiring a lathe or drillpress. I linger with pleasure over the photos. There is beauty here in your remembrance of some beautiful machines.

August

Page 3 of this thread, near the bottom, has a post
by simon le bon » Sun Jul 25, 2010,
with an image that seems to be making its way into the pop culture.

Today Lady Gaga's Facebook page featured this image:
https://littlemonsters.com/post/52d986cec214e4e4488b4c27

August

I found only these notes in the SketchUp manual about pre-processing photos:

Do not crop photos. Match Photo currently requires that the point you aimed the camera at is located in the center of the image (also called the center of projection). Although it may seem possible to use a cropped image, typically vertical lines will not align well across a cropped image and the results will be unsatisfactory.
Do not warp photos. Images which have been manually warped using an image processing program, or specialized camera, are not supported by Match Photo.
Remove barrel distortion or issues where straight lines are bent away from the center of the image. Barrel distortion typically occurs on wide angle lens cameras. Use a third-party product to eliminate barrel distortion from images prior to using them within Match Photo. All cameras have a little bit of this distortion and it is typically worse around the edges of the image.

Point 1 is the most repeated advice about Match Photo.

Point 2, about warped photos, would seem to me to exclude using ShiftN. I can imagine using ShiftN to apply photo textures, but I presume its distortion of the photos will make them unsuitable for Match Photo.

Point 3 is what I assume Thomthom was referring to by "lens distortion". This lens appears to be excellent in that respect. It is extremely hard to find any evidence of barrel distortion.

But, as I reported earlier, I appear to have non-square pixels, the images as displayed are all a bit narrower than the model.

If anyone has any experience with how to accurately test that aspect of a camera lens, I would appreciate any suggestions. I will probably be working out my own tests this coming weekend.

I presume I will need a way to accurately identify the position of the center of the lens while the camera is on a tripod pointed at a flat surface that is exactly perpendicular to the camera's line of sight.

Theory is easy. Construction still awaits a design.

A brute-force approach would be to simply try different values for the adjustment until I find one that seems pretty good. But since it can take up to an hour of fussing and fiddling to reach what I consider my best compromise, that approach is guaranteed to take a few hours.

Again, brilliant ideas are always welcome.

Thanks,
August

August

@thomthom said:

Did you remove lens distortion? (Manual recommend so)
There are so many things that affect the accuracy of PM.

I had been reasonably confident about my lens because my Sony camera said it had a Carl Zeiss lens. So I had done no post-processing of the images. I had done some checking and the lens does a very good job of keeping straight lines straight, even at fairly wide angle settings.

However...

I measured the big rectangular box and made the model box the exact dimensions. After another hour of fitting the photos to the rectangular model, I have come to two conclusions:

There are lines that I had been assuming were parallel to the outer edges of the unit which are not exactly parallel. In particular, there is one corner flashing that has definite bend at one end.
The camera pixels are not "square". After much fiddling, I have all four photos in very close alignment with the exception that the overall width of the images is too narrow to fit the model box by about the same visual amount in each photo.
I had previously thought that non-square pixels would only matter if I rotated the camera to take a "portrait" style instead of a "landscape" style photo. But I have realized from this exercise that Match Photo assumes square pixels and an error of, for example, 3% in the width will produce a different error in the model according to the angle that face is at with respect to the camera. Adjusting that width to fit will thus produce different proportionate errors in height -- and that is what I had been seeing.

So at this point, it looks like I need to set up an accurate test to find out what post-processing it will take to get square pixels from this camera.

I am hopeful that I will be able to do something simple like expand the width of each photo by, for example, 3.5% and then be able to much more quickly get them to match each other in Match Photo and thus be able to produce a consistent model much more quickly than trying to compromise between images that will never match.

Thanks for all the help and suggestions.

August

August

@unknownuser said:

ShiftN

Cool app. But I think it would mess up Match Photo every bit as bad as cropping does.

If it is just for photo textures, I think it might work very well, but but using photos to get 3D position is a different problem.

Thanks.

August

@pbacot said:

There are similar cloud applications and experiments out there.

Are you familiar with any specifically? I'm not even sure what terms to google.

August

It is for "fun" in the sense that I am trying new things so that I can learn about them as I experiment.

And it also has a pragmatic purpose. I am trying to model the space under one corner of my house to design exactly how a new furnace can be installed there, what it will need for a mounting base, how it will connect to the existing ducts, where the water and drain pipes are, etc.

A local furnace contractor wants nearly $2000 to do the installation, plus the cost of the furnace. I am hoping that my SU model will allow me to do it myself, or mostly, substituting intense planning for hands-on experience in this kind of installation. All the basic construction, electrical, and plumbing skills I already have, I just have not done exactly this before. So in that sense this is a "paying" project. I am imagining that this SU model will be worth as much as $1000 to me.

I am also expecting that this little bit of code from Chris Fulmer will be helpful.
http://forums.sketchucation.com/viewtopic.php?f=323&t=28154&start=15#p245418

This Ruby code draws construction lines through the camera eye point and wherever in the view the mouse is clicked. So I am imagining that I can go through one photo, placing C-lines through each ping-pong ball, then do the same for another photo, and where the lines cross in the model will be my surface points.

Of course, that is assuming the lines cross. Given my current problems with Match Photo, I'm being cautious about that idea.

August

The photos of Bertier's tool remind me of what I have been considering for a later stage of my project.

After I have the foundation and floor joists in place in the model, I want to model the earth between the foundation walls. I think this is a similar problem to Bertier's, except that I will not need his tool because I will have the building foundation to determine horizontal and vertical.

To find matching points of the irregular earth surface, I have thought of adapting a technique from Hollywood: My idea is to cut ping-pong balls in half and place them about one foot apart all across the irregular surface. Ping-pong balls come not only in white but in bright fluorescent yellow, which should be ideal.

In the photos, no matter what angle they are seen from, the perimeter of the ball will identify exactly where the center of the ball is so I can match those center points from photo to photo.

In Bertier's photos, the yellow flowers in the grass are similar to the ping-pong balls. There are patterns in the flowers that let you match the same flower from photo to photo.

Has anyone done anything like this before? Should I start a new thread to ask the question?

Thanks.

P.S. I'm still working on the original furnace-box problem. I haven't had any time for it the past few days.

August

I am trying to start a match photo project because I thought it would be the easy way to create a model of a corner of my house that I will need for a renovation project.

But in just getting started, I have quickly reached a place where I am stumped about what is going on.

I can match two photos to 1/8" accuracy and I can match two other photos to the same accuracy, but I cannot get the two sets to correspond to each other. There is a several inch difference in only one dimension between the two model worlds.

To get the model started, I shot some pictures of the exterior furnace and air-conditioning unit. A big metal rectangular box should be easy an easy point to "anchor" the match photo model, I thought. I did not change the camera between shots except to focus.

I got a box to fit the first photo, but it would not match the second without push-pulling the top by several inches. So I added a third photo and got a really good match between it and the second photo, but the same problem matching the first. Then I added a fourth and it matched the first really well, but not #2 and #3.

So with my model box at one height I can match two photos and with it about 20% shorter I can match two other photos. I am stumped.

I have spent some hours now trying to get the photos and model to makes sense. Now I have spent additional hours searching this and the google forum, trying to find anyone who seems to have had this problem before.

I will make up screenshots to provide a clearer explanation of the construction and the problem, but before I do, I wanted to ask if this rings any bells for anyone.

Thanks,
August

August

Wow. Thank you for such a quick response.

The more I thought about it, the more I began to think that the error could have come from measuring the original, default 20-segment length, dividing that, and applying that new length to the new segments. Going from 20 segments to 32 segments could indeed introduce just that order of magnitude error.

But before I could experiment with that theory, here you are with the problem fixed. Wow.

No point now in my trying to figure out what the issue used to be.

Thanks again,
August

August

I think I have found a calculation bug in the the Polyline Segmentor. The last segment seems to come out the wrong length for no apparent reason.

Fredo6's BezierSpline has been used by so many people for so long that I am hesitant to call what I am seeing a bug. But I suspect that it has been there all along. In exploring the manual, tutorials, etc. I have found phrases that take it for granted that this happens when I cannot see the reason for it.

I see descriptions of using the Polyline Divider that say the last segment will not be the same length as the others. That makes sense. The overall length is arbitrary and the segment length is fixed; of course there will be remainder.

But I see phrases that apply that same caveat to the Polyline Segmentor and that does not make sense. You are dividing a curve into a whole number of segments. There should be no remainder. If there is some calculation round off, it should be minuscule, down in the 9th or 10th decimal place. But what I am seeing is an error of nearly FIVE PERCENT.

I draw a Classic Bezier curve and I use Convert to Polyline Segmentor and I specify 32 segments. I would think those would be all the same length, or nearly, and so they are, except the imprecision of the last segment has me baffled about why it would be so different. 31 of the segments are 2.099221" in length and the final segment is 2.005871". That is a 4.65% difference.

Certainly SU Ruby is capable of more precise calculations than seem to be in use here.

That difference is barely noticeable in the curve, but these points will be the reference points for attaching more complicated structures that will come close to each other and I am afraid that when the final construction is done, there will be an aesthetic glitch, at the same level as bad kerning between typeset characters in a title. What is a 5% difference initially could become a much larger difference down the road. And 5% is itself a big enough a difference to see without measuring.

My design calls for repeating the same curve, attaching it to the previous copy, then attaching repeating elements at each curve point. I don't want the spacing of the larger elements to be visibly too tight at each and every inflection point. It will just look wrong.

I tried scaling everything up 10x before I used the Polyline Segmentor and the new numbers were 20.992211 and 20.058708, merely another decimal point of precision in my display. It's not the "too tiny" SU bug or the numbers would have changed a bit. I'm sure the underlying numbers are consistently inconsistent.

So is this a bug in Polyline Segmentor, or is this a necessity? And either way, is there a workaround? Any suggestions welcome.

Thanks,
August

P.S. I am using the very latest BezierSpline, downloaded two days ago, running on Windows 7, SU 8.0.14346, also the latest version.

August

My guess, without a reply from Adam, is that the 38,000 number is half of the number shown. The math works between what is shown and what Adam said. But why half? Well, if he is counting the number of edges of each face, most edges are going to be counted twice. It would only be ALL edges counted twice if the object was a "manifold", closed 3D shape with no floating bits of faces anywhere.

That's my guess,
August

August

IIRC, there is something along those lines among the "Solid" tools of SU 8 Pro, too.

August

I'm resurrecting an old thread, but this seems the appropriate place to bring this up.

There is a SourceForge project for STL4SU that imports, exports, and recognizes and handles both binary and ASCII files.

http://sourceforge.net/projects/stl4su/files/

I have just downloaded it and will be trying it out over the next couple of days. It consists of a Readme.TXT file and the stl4su.rb file. There is also a DMG file for Mac folks that is 3+ times the size.

I'm going to be attempting to 3D-print the Universal Construction Kit (Free).

http://fffff.at/free-universal-construction-kit/

We will see how that goes. Someone, somewhere, mentioned that one of the parts in the kit got kicked out as not "manifold".