[Plugin] Bitmap To Mesh

[Dave R]

1.25 million entities? That would let the magic smoke out of this computer for sure.

[jeff hammond]

with this bmp, i added a few extra pixels along the top and bottom making it an even 125x500px which brought the entities down by 75%..
(make sure to scale the y axis to 25% in order to fix the proportions)

Untitled-1.bmp.zip

untitled1.jpg

[dedmin]

No, there is a similar command in Rhino - Mesh Heightfield. I just used your image to test it - the mesh is quite small 33 by 8 by 1,3 mm. I doubt this can be done in SketchUP.

[dedmin]

And Rhino maps the image as a texture

Untitled-1.jpg

2010-10-01_221122.jpg

2010-10-01_221044.jpg

[notareal]

Nice one! I can imagine that one day this will be in need.

[Dave R]

Dedmin, that looks nice.

I did make the heighfield map in SketchUp so I know that part can be done. Here's the mesh from which I made the map.

[dedmin]

Sure - I mean the plugin. Can that plugin make so small mesh from an image without scaling? Looks good Dave
By the way, did You notice that Layout 3 can now paste Excel tables - very handy!

[shura]

Jeff, that concentric wave looks great!

Thomas, sorry but I won't be able to get out of Berlin atm. We are preparing to move to a new appartment with my son being only six weeks old, and Munich is 600km from here...
Enjoy your time there - and don't forget that not all of us germs wear leather pants and drink beer until they pass out.

alex

[thomthom]

and don't forget that not all of us germs wear leather pants and drink beer until they pass out.

What?! I've been lied to!!

[thomthom]

yeah, it works in sketchup..
tt's script scales everything to a square so i made the mistake of adding more black for an overall 500x500 px (4times the recommended resolution of 250x250)..

it came in at a modest 1.25 million entities

I'll update it with a tool for placing the mesh in the model, with correction aspect ratio and let you define a height - basically let you draw a bounding box.
Maybe even with an option to sample less pixels.

[thomthom]

Maybe even with an option to sample less pixels.

Or... Maybe interpolate pixels... Though - the same could be done by the user by just scaling down the image...

[Dave R]

Dedmin, thanks. Since I haven't been able to do it yet, I don't know but I fully expect I'd have to scale the mesh to the right size. Looks like Jeff managed it, though.

As to the excel tables into LO, yes. I did see that. You can't do anything about formatting once it is in, though. Oh well, maybe in LO4.

[shura]

just used an alpha map and deleted the lower part of the mesh, then flattened it. not talking about quality, but at least it looks like some sort of image tracing...

zz.jpg

[ken28875]

Wow!

You keep on amazing me with your plugins, Thomas! You're the man.

Thank you very much,

_KN

[Chris Fullmer]

Test with simple displacement map:

Displacement.png

MMMmmmm, a plugin that makes chocolate bars. I'm hungry now!

[thomthom]

[MALAISE]

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Thank you really very much for all the plugins you give us.

MALAISE

[Dave R]

Except with very small BMP files, I don't seem to have any luck. Even with a small BMP file it takes a long time to process but that could just be my computer.

Coen's comment though is intriguing. I was thinking this plugin could be a neat way to get line drawings into SketchUp. I made the attached line drawing as a quick test and got the second image as a result. I inverted the image and got the results in the third image. I wonder if it would be possible to have a control to somehow limit the range in the gray scale. Perhaps any RGB value less than, say, 250,250,250 gets read as 0,0,0? Or perhaps no height is assigned? Perhaps it isn't possible but I wonder.

[Rich O Brien]

Making Knuckle-Dusters Dave?

[Dave R]

Maybe I should. I was just doodling on the pad using AutoDesk Sketchbook.

[thomthom]

I wonder if it would be possible to have a control to somehow limit the range in the gray scale. Perhaps any RGB value less than, say, 250,250,250 gets read as 0,0,0? Or perhaps no height is assigned? Perhaps it isn't possible but I wonder.

It's technical possible to read values lower than 250 as 0, but I don't quite get why?
Though you can do it in PS (or similar) by adjusting the Levels.)


I have an idea of how to make the mesh less spiky though, but it needs some experimenting.

[Dave R]

I was just thinking that setting some limit so that everything is either black or white and not shades of gray would get rid of the spikes.

Would it be possible to work things so that a face is created only if the value is less than some set point (250,250,250?) and the face is always at Z=0? Delete coplanar edges between faces and you'd have a raster to SKP converter.

[Rich O Brien]

I like that idea

Kind of Footprint or Ink Stamp tool, lots of uses for it too!

[thomthom]

I was just thinking that setting some limit so that everything is either black or white and not shades of gray would get rid of the spikes.

The spikes you see if much due to the extreme height of the mesh, and part due to the current triangulation. I'm not sure if making the contrast bigger will reduce then - in either case, Ruby isn't efficient for image manipulation - you'd be just as well off just preparing the image before in an proper image editor.

Would it be possible to work things so that a face is created only if the value is less than some set point (250,250,250?) and the face is always at Z=0? Delete coplanar edges between faces and you'd have a raster to SKP converter.

It'd be an interesting new tool, but I still think it's best if the image is prepared by the user in an editor and made into complete Black and White (not grey scale).

Then the tool could read all the white or black and generate a mesh - where it could then afterwards trace the outline and remove the interior lines. After running an curve simplification, like the Douglas-Peucker algorithm, and you could end up with a decent vectorized shape from your raster mask.

This would have been so much better if I could read the alpha channel of PNG files. I was a looking at this some time ago, but existing too many third party libraries for my comfort which makes redistribution more complex. The alternative, making a pure standalone ruby PNG interpreter wasn't so easy either, the decompression algorithm wasn't the easiest.

[Dave R]

Well, it's all voodoo to me so I am glad we have folks like you.

[thomthom]

Version 0.2.0b

• Made into a tool so the user can easily position the mesh
• Moved menu to Draw > Mesh From Bitmap
• Keeps aspect ratio of image or Image element
• Right click and Image element to generate a mesh. (Does not need to be BMP image - but Draw > Mesh From Bitmap still require BMP imput)
• Colour BMP images will convert the RGB value to optical greyscale.
• VCB support

[thomthom]

TerrainTest.png

Test using sample maps from: http://www.mtgrafix.com/programs/terrain.html

Also tried this: http://www.twisteddirt.com/TutorialStuff/dem_02.php Nice terrain shape - but the diffuse texture wasn't so good.

[dedmin]

or-a-24-0039.jpg

2010-10-03_185534.jpg

2010-10-03_185511.jpg

[thomthom]

308px × 1 047px - that would make the mesh ~500-600K faces?

And the issue with that bitmap is that despite it being a greyscale, it's still not a height map - which is why the mesh doesn't come out looking as what the image illustrate.

[dedmin]

Yes, true. I just wanted to test it - the file is 105 MB