I have a custom graph algorithm and graph with some additional data in it, and I want to create a tool which creates this graph (Shape and size will be asked via UI) and then modifies it in some way. I tried simple forms and then processing the data with python, outputting and showing a graphviz converted to png. Graphviz makes edgeless graphs in an ugly way - they are in one line.
My goal is to create something more interactive, and user friendlier. My friends recommended me to do this in Unity, although, I have no experience with it. And internet recommends me javascript, but I have been always avoiding web as much as I could... So my Weapons are: Python, Java, C++ (I prefer Python). The tool is not meant to be commercial, it is for educational purposes only. Maybe there is really some simple way I am still missing. I want something similar to this: https://www.cs.usfca.edu/~galles/visualization/BTree.html
Related
I was wondering if anybody knew of an easy, robust way to generate depth images from 3d models (i.e. surface models, vertices with faces), with specifiable camera parameters.
I'd prefer "free" options if possible (e.g. pyOpengl or some open source Java library rather than say matlab).
I believe it is possible with the python blender api (noted here), but I'm hoping there's an easier way.
Note also that this question works only for that special case.
You can use DECA repository in Github. There, in ./demos, I used demo_reconstruct.py code to save the depth image.
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 developing an online assessment package for elementary grade math (K-6) Many questions will need to contain graphics such as shown on this image:
https://www.dropbox.com/s/xwsi91l3bp9t3de/samplegraphics.PNG
All graphics needs to be generated on-the-fly (apart from photos of real objects that are stored in a database) - so that unlimited number of problems can be created). Another requirement is that this works well on both desktop and mobile devices.
I am looking for an advice as to what language / graphics package would be best suited for this purpose. I would rather do everything in one environment. If some of the above can not be generated on the fly, I would consider (but not prefer) off-line generation of many examples that are then stored in a database.
I have considered the following
php+gd -- seems nice for manipulating images; however 3D not readily available.
jpgraph.net/features/gallery.php seems like a nice addition for spiffy graphs
There also seems to be a 3D rendered for php phpclasses.org/package/3364-PHP-Compose-and-render-3D-object-models.html -- my 3D requirements are modest (basic shapes, no animation)
JS with different plugins i.e. threejs.org/ for 3D - but this seems like an overkill for my needs
there is also js interface to html 5 canvas : calebevans.me/projects/jcanvas/
and this: keith-wood.name/svgRef.html
Google charts also seems very simple to use, but it doesn't provide everything I need
CSS3 - seems like it can do everything (??)
gnuplot (??) - not on-the-fly
Basically, I am looking for the easiest way to accomplish this, without reinventing the wheel - I am just not quite sure what the trade-offs of different approaches are.
I have an application that uses intricate graph-like structure as a configuration. The application itself resembles a NetGraph- or netfilter firewall, thus graph nodes have types and properties (which correspond to operations) and they're interconnected with directed edges.
I'd like to have an easy-to-user configuration editor for my application that provides visualization and editing for configuration as a graph.
In my dream scenario, application would receive this configuration as a file in one of popular graph formats (for example, TGF, DOT, GraphML, etc), parse it and use.
A few requirements (not really strict, I'm open to consider various options) - graph editor should be:
available to be embedded in web UI - i.e. implemented in Javascript/HTML, Flash or as a Java applet
able to load TGF-style graph (i.e. without layouting instructions, nodes would be without coordinates) and lay it out in a somewhat decent automatically
able to save this graph back
able to load/save using requests to HTTP server, not a file directly
customizable to make it work with strict set of node types (so that user can't just create arbitrary node type or arbitrary properties for a given node)
open-source
So far I've found yEd and it's Flash version, Graphity - both look cool, but they aren't customizable (to strip them to bare-bones functionality, i.e. creation of one a few node types) and not open source, so embedding them anywhere pledges to be somewhat painful.
Another option I'm considering is trashing the whole "visual editor" idea and make user just write down bare TGF or DOT-style definitions in a plain text file and visualize them for later checking using something like GraphViz. Is it a viable way to go?
Have you looked at InfoVis? In particular, the force-directed layout and editing may be applicable. Graph source data is analogous to DOT, albeit in json format. No layout info in the source data though.
EDIT: There's also ProtoVis which is similar.
hth.
Im writing a game engine and I'm wondering what 3D model format should I use/load/export? Obj seems universal and easy but it also appears to be unreliable in that most models out there contain errors and it doesn't store anywhere near as much as other formats.
There appear to be formats specifically for games such as MD2/3/5 but Im not sure, I use wings3d if I model, and I don't know what other details beyond purely loading what I need and support from the format Id have to implement, such as would I need to implement IK? and can I use scripted per piece animation rather than Inverse kinematics and bone rigging?
Collada is an open XML based format for 3d models owned by the Khronos group(OpenGL standards body)
From the Collada.org FAQ:
The COLLADA 1.4.x feature set includes:
Mesh geometry
Transform hierarchy (rotation, translation, shear, scale, matrix)
Effects
Shaders (Cg, GLSL, GLES)
Materials
Textures
Lights
Cameras
Skinning
Animation
Physics (rigid bodies, constraints, rag dolls, collision, volumes)
Instantiation
Techniques
Multirepresentations
Assets
User data
Before worrying about what 3D formats you want to support, I think you should really focus on what features you are planning to implement in your engine. Write those down as requirements, and pick the format that supports the most features from the list... as you'll want to showcase your engine (I am assuming you are planning for your engine to be publicly available). You might even want to roll your own format, if your engine has specific features (which is always a good thing to have for a game engine).
After that, support as many of the popular formats as you can (.X, .3DS, .OBJ, .B3D)... the more accessible your engine is, the more people will want to work with it!
Collada is a nice and generic format, but like Nils mentions, it is not an ideal format for final deployment.
I use my own binary format. I've tried to use existing formats but always run into limitations. Some could be worked around, others where showstoppers.
Collada may be worth a look. I don't think that it's that good as a format to be read by a 3D engine. It's fine as a general data-exchange format though.
http://www.collada.org/mediawiki/index.php/Main_Page
+1 for Collada. You may also want a custom native binary format for really fast loading (usually just a binary dump of vertex/index buffer data, plus material and skeleton data, and collision data if appropriate).
One trend in the games industry is to support loading a format like collada in the developer build of the engine, but also have a toolchain that exports an optimized version for release. The developer version can update the mesh dynamically, so as artists save changes, the file is automatically reloaded allowing them an (almost) instant WYSIWYG view of their model, but still providing a fully optimised release format.
support Collada well, and then supply good converters to/from the other formats (this might be the hard part). This will give you maximum flexibility. Take a look at C4 engine
Collada is great, but it lives more on the 3D app side of things. ie it's best used for transferring 3D data between applications, not loading 3D data from within a games engine. Have you looked into Lua? It's widely used in games because its a scripting language that's both ridiculously quick (perfect for games) and very flexible (can be used to represent whatever data you need for your engine).