I want to write an app that takes in a model filename via cmd line, create a list of stats (poly count, scaling, as much as possible or maybe the stats that i would like) and to load the model with its textures (with anything else) and draw it from multiple position to save the images as pngs.
How would i do this? are there utils i can use to extract data from models? how about drawing the models? my server does not have a desktop or video card, would no video HW be a problem?
You can use http://www.lib3ds.org/ for reading the data, IIRC it also comes with a sample program that you could base your code on.
Have a look at the 3DS specifications at wotsit.org. AFAIK, there are no official specs. Another possibility would be to look for open source 3DS libraries/tools and use them.
Related
I am writing a program that will output 3D model files based on simple geometric shapes (e. g. rectangular prisms & cylinders) with known coordinates in 3-dimensional space. As an example, imagine creating a 3D model of stonehenge. this question suggests that OBJ files are the easiest to generate, but I'm struggling to find a good tutorial or easy-to-use library for doing so.
Can anyone either
(1) describe step-by-step how to create a simple file OR
(2) point me to a tutorial that describes how to do so
Notes:
* Using a GUI-based program to draw such files is not an option for me
* I have no prior experience with 3D modeling
* Other formats such as WRL or DAE would work for me as well
EDIT:
I do not need to use textures, just combinations of simple geometric shapes positioned in 3D space.
I strongly recommend to use some ASCII exchange format there are many out there I usually use these:
*.x DirectX object (it is a C++ source code)
this one is easiest to implement !!! But there are not many tools that can handle them. If you do not want to spend too much time coding then this is the right choice. Just copy the templates (at the start) from any *.x file to get started.
here some specs
*.iges common and importable on most CAD/CAM platform (Catia included)
this one is a bit complicated but for export purposes it is not that bad. It supports Volume operation like +,-,&,^ which are VERY HARD to implement properly but you do not have to use them :)
*.dxf AutoCAD exchange format
this one is even more complicated then IGES. I do not recommend to use it
*.ac AC3D
I first saw this one in flight gear.
here some specs
at first look it is quite easy but the sub-object implementation is really tricky. Unless you use it you should be fine.
This approach is easily verifiable in note pad or by loading to some 3D model viewer. Chose one that is most suitable for your needs and code save/load function to your Apps internal model class/struct. This way you will be compatible with other software and eliminate incompatibility problems which are native to creating 'almost known' binary formats like 3ds,...
In your case I would use IGES (Initial Graphics Exchange Specification)
For export you do not need to implement all just few basic shapes so it would not be too difficult. I code importers which are much much more complicated. Mine IGES loader class is about 30KB of C++ source code look here for more info
You did not provide any info about your 3D mesh model structure and capabilities
like what primitives you use, are your object simple or in skeleton hierarchy, are you using textures, and more ... so it is impossible to answer
Anyway export often looks like this:
create header and structure of target file format
if the format has any directory structure fill it and write it (IGES)
for sub-objects do not forget to add transformation matrices ...
write the chunks you need (points list, faces list, normals, ...)
With ASCII formats you can do this inside String variable so you can easily insert into or modify. Do all thing in memory and write the whole thing to file at the end which is fast and also add capability to work with memory instead of files. This is handy if you want to pack many files to single package file like *.pak or send/receive files through IPC or LAN ...
[Edit1] more about IGES
fileformat specs
I learned IGES from this pdf ... Have no clue where from I got it but this was first valid link I found in google today. I am sure there is some non registration link out there too. It is about 13.7 MB and original name IGES5-3_forDownload.pdf.
win32 viewer
this is free IGES viewer. I do not like the interface and handling but it works. It is necessary to have functional viewer for testing yours ...
examples
here are many tutorial files for many entities there are 3 sub-links (igs,peek,gif) where you can see example file in more ways for better understanding.
exporting to IGES
you did not provide any info about your 3D mesh internal structure so I can not help with export. There are many ways to export the same way so pick one that is closest to your App 3D mesh representation. For example you can use:
point cloud
rotation surfaces
rectangle (QUAD) surfaces
border lines representation (non solid)
trim surface and many more ...
I am doing one experiment in which I need to capture skeleton data from kinect and then apply that data to a model, I have captured data from kinect and have stored it in a file, i.e in a file i have location of each joint in each frame,
Now I want my model in blender to take the joint position from file, and move accordingly. But I dont have any idea on how to start.
I also have written a small script in python to read position from file and update the position of one bone:
obj.channels['head'].location = Vector((float(xs),float(ys),float(zs)))
but it does not move anything. Am I doing it in wrong way, or we cannot move the armature by just updating the position??
Please guide me on this topic, as i am completely new to python and blender
I don't think that this is the best solution, you can simply export your data to a bvh file and save yourself from a lot of headaches.
You can find a lot of Kinect-sdk to bvh tutorials on the net and the bvh is the de-facto standard to store data from motion capture events, there are no reasons why you should re-invent the wheel and doing extra work.
To use your bvh file in Blender you can simply follow one of the many tutorial on the subject.
I like the idea of Nodebox and Processing, and would like to generate movies to visualize some data/algorithms. However, Nodebox exports extremely bloated Quicktime files with frame by frame images, and Processing only exports Java applications. I want to be able to export movies that don't take a Gigabyte a minute of disk space. Perhaps something like SVG animations or Actionscript which stores the vector graphics definition of the animation rather than frame images would be better. Is there a framework that is as easy to program as Nodebox and Processing and can export "lean" movies?
Have you tried the MovieMaker library that ships with Processing ?
Also, it should be fairly simple to save multiple frames using saveFrame().
This is option have a couple of advantages:
If your sketch crashes at some point, you still have all the frames up to that point (unlike writing a .mov file)
It's fairly simple to put the frames back into a video file, but you also have control over playback speed and can easily do a bit of editing if needed.
You can try to a sequence of PDF file using createGraphics() to get vector output, but I'm not sure how stable/feasible this option is.
They are changing the way this works moving towards 2.0 too, as they are moving to GSVideo over Quicktime...
Daniel Shiffman posted about it recently on his blog, but it's the only place I've heard about any changes to post-2.0 tactics (though he IS part of the inner circle, I know)
You can find that post at
http://www.shiffman.net/2011/12/28/night-8-rendering-out-as-image-sequence/
Also, if you are on OSX, you can try Syphon ? See info here
https://forum.processing.org/topic/syphon-integration-with-processing
BACKGROUND
I am using a commercial application on windows that creates a drawing
This application allows only two output options: (1) save as a bitmap file and (2) print to a printer
the bitmap is useless for my purposes - I want the vectors
Looking at the print output (I sent to the Windows XPS print driver) it seems clear based on the amount of zooming I can do without loss of detail that the underlying vectors are being send to the print driver
Once I get the vectors, I will be writing some code to transform them for some other use.
MY QUESTION
Whart are my options for geting the vectors from the print? (am open to both commercial and open source)
OPTIONS I HAVE THOUGHT OF SO FAR
Take the bitmap and use a program like VectorMagick to. I have tried this approach. It does not produce the fidelity I seek even when the original bitmap is large. Practically speaking I believe that using any tracing approach will not give me the quality vectors I need.
Print to the Adobe PDF driver. This technically works. I have Adobe CS4 so I can print to it save the resulting PDF and then import the PDF into Illustrator and then export as some other vector format. The problem with this approach is money/licensing. I own a personal copy of Adobe CS4 - so this is fine for me. But I need to capture the vectors at work for business purposes - and no I'm not going to install my personal copy of CS4 at work.
Is there a "print driver" that captures the print output directly into a vector format? I have seen some commercial ones via google. If you've used them, I would like to hear about your experience with this technique. I could write my own and in that case do you have links to any existing code that I can start with.
If this is an ongoing solution you need then you might need to buy something or build your own. If it's a onetime affair you might look to use an 'older' Lexmark PCL printer driver. I'd recommend something like the T610. If you download the PCL driver and install it you can modify the defaults and change the Graphics option from XL or Autoselect to GL/2. This will force the driver to output GL/2 output which is vector (GL/2 is a plotter language). This might do the trick for you. Other printer drivers may have the abiltiy to force GL/2 (vs. Raster) but I'm not sure. I use to work for Lexmark and have used this before for a similar requirement.
Ensure you use the Lexmark 'Custom' driver as I don't think the Microsoft-based one support this feature.
...pausing while I investigate a few things............I'm back...
Another option is to find another GL/2 driver or build you own...I just took a few minutes to search the web and came up with a few other options that might work.
Build you own:
I've built drivers (minidrivers) using the Windows Driver Development Kit (DDK), it's quite simple to construct basic drivers. Looks like there is a setting you can set to enable GL/2 output: Enabling HP-GL/2 Vector Graphics Support (PCL-5e) in the GPD
Alternate drivers:
Depending on the OS you are on there is probably a 'generic' GL/2 driver built in. I believe XP has a Hewlett-Packard HP-GL/2 Plotter. You might need to check the license (as with the Lexmark solution) but it might work for you and as it's part of the OS there shouldn't be concern about using it. It's probably written and copyrighted to Microsoft
Keep in mind you will have to do some work to convert GL/2 to whatever output you want but it should be a matter of an simple translator to convert each set of commands. There may be tools out there to help. Here is a quick link to Lexmark GL/2 reference which might be enough to get you going, check out the GL/2 information under the PCL section: Lexmark Technical Reference Guide
Postscript:
The last option I have is to use a generic Postscript driver. Postscript should output the vector images as vector graphics in the Postscript but my knowledge of this is limited at best.
Output:
If you need the output to route to file you can set the port to FILE: which requries user intervention, or install something like Redmon (or connect with me and I'll send you our port monitor that allows for automatic output to file).
Hope this helps in some way.
My favorite is the open source (GPL) PDFCreator
http://sourceforge.net/projects/emfprinter/
I need to program a util for a 3d model. What i need to do is pass the 3d model to the util and have it extract multiple information. Things like poly count, size/scale (if applicable) and anything else i can grab. Then i need to take a screen shot of the model 8 times (45deg from 0 to 360). Maybe 16. Is there an app that i can use to extract data from the model and is there another app i can use to create the image? if so i can write a php script to do this all for me :) if not i'll post more question about specifics.
My OS is debian etch
the models will be any format. I may make it 3ds only or limit it to what the app(s) support. Or i may have another app to convert one format to the other and extract the data from that format.
I haven't tried this, but you could try 3ds2pov to convert your 3DS files into POV-Ray format, and then render with POV-Ray.
The 3ds2pov program is quite old, so I don't know how compatible it is with current 3DS files. The archive comes with source code so ought to build without too much difficulty on Debian.
POV-Ray itself runs easily on Linux.
nb: other 3DS to POV converters may exist. This one just happens to be the first one returned by Googling for "3ds to pov".
Your requirements are very loose and vague but most 3d engines should have the tools you need to create your custom utility. I would start by looking at Blender or the viewer tools from OGRE, OpensceneGraph and similar tools.
You can try this: Linux based A3dsViewer -> does 3ds to pov conversion.