We Keep Coding

.asc viewer using Kivy

I want to develop a 3D file viewer in kivy and python that reads and displays .asc mesh files of the format:
x1,y1,z1
x2,y2,z2
........
xi,yi,zi
What I have thought so far is to use a method similar to beginShape() of Processing so as to begin drawing a 3D shape then use a for-loop to append each point respectively.
I have also found that kivy example which parses .obj files and then displays them. Do you have any ideas on how can I make a similar ascparser and try to display my files?
Any help is greatly appreciated

I have also found that kivy example which parses .obj files and then displays them. Do you have any ideas on how can I make a similar ascparser and try to display my files?
Your best strategy at the moment is probably to read the objparser and try to understand what it is doing. The important thing is building a list of points and normals, which are passed to opengl via a Mesh with a custom vertex_format and custom shaders. In principle it wouldn't be very hard to do the same thing for your own filetype just by comparison with the .obj code, though you will need some understanding of what's going on (you can read about opengl and read the kivy source, if you haven't already) to make significant changes.
This is really an advanced topic right now, Kivy has very few pre-built wrappers to 3d opengl rendering. The backend is fully capable (so the 3d rendering example isn't that complex, for instance), but you probably do need some understanding of what's going on to accomplish things like your own task.
There are also a few other examples of 3d rendering in Kivy, which you might find helpful. nskrypnik has several repositories doing just this (see kivy-trackball, kivy-3dpicking, kivy-rotation3d), and seems to have begun implementing a proper 3d api in the kivy3 repo, though this is not complete and I suggest it as something you can learn about by reading, not something that can necessarily do what you want right now. The other nice example I've seen is a 3d inspector POC by tito, though it's just a proof of concept and not a polished product.

Render 3D model orthographically in Python

I want to write a tool in Python that will help me create isometric tiles from 3D-models. You see, I'm not a very proficient artist and free 3D-models are plentisome, and creating something like a table or chair is much easer in 3D than in painting.
This script will load a 3D model in orthographic projection and take pictures from four directions so it can be used in a game. I've tried this in Blender, but the results are inconsistent, very difficult to control and take very long time to create simple sprites.
Rolling my own script will probably let me do neat things too, especially batch-genetration, maybe on texture changes, shading, etc. The game itself will probably be made in Python tpp, so maybe I could generate on the fly. (Edit: and automatically creat cut out see-through walls for when they face camera)
Now my question, what Python libraries can do something like this? I've checked both Pyglet and Panda3D, but I haven't even been able to load a model, let alone set it to orthographic projection.

I found this code:
www.pygame.org/wiki/OBJFileLoader
It let me load and display an .obj file of a cube from Blender with ease. It runs PyOpenGL so it should let me do everything OpenGL can. Never knew OpenGL was so low-level, didn't realize I'd have to write my own loaders and everything.
Anyway, I'm pretty sure I can modify this to project isometrically, rotate the object and grab shots and combine them into sprites. Thanks you guys!

Since you looked at Panda3D - if you can convert your model to the 'egg' format (which blender/maya may do), then you could be able to import it.
https://www.panda3d.org/manual/index.php/Loading_Models
https://www.panda3d.org/manual/index.php/Models_and_Actors
http://www.panda3d.org/manual/index.php/Converting_from_Blender
Note: sources of this was 'python 3d mesh loader' in a popular search engine - this looks viable to me. I now need to try installing it and some code...

Best 3D library to model robotic motion [closed]

Closed. This question does not meet Stack Overflow guidelines. It is not currently accepting answers.
We don’t allow questions seeking recommendations for books, tools, software libraries, and more. You can edit the question so it can be answered with facts and citations.
Closed 4 years ago.
Improve this question
A short while I asked for suggestions on choosing a Python-compatible 3D graphics library for robotic motion modelling (using inverse kinematics in Python). After doing a bit of research and redefining my objectives I hope I can ask once again for a bit of assistance.
At the time I thought Blender was the best option - but now I'm having doubts. One key objective I have is the ability integrate the model into a custom GUI (wxPython). Seems like this might be rather difficult (and I'm unsure of the performance requirements).
I think I'm now leaning more towards OpenGL (PyOpenGL + wxglcanvas), but I'm still struggling to to determine if it's the right tool for the job. I'm more of a CAD person, so I have trouble envisioning how to draw complex objects in the API and create motion. I read I could design the object in, say Blender, then import it into OpenGL somehow, but I'm unsure of the process? And how difficult is manipulating motion of objects? For example, if I create a joint between two links, and I move one link, would the other link move dynamically according to the first, or would I need to program each link's movement independently?
Have I missed any obvious tools? I'm not looking for complete robotic modelling packages, I would like to start from scratch so I can incorporate it into my own program. For for learning more than anything. So far I've already looked into vPython, Pyglet, Panda3D, Ogre, and several professional CAD packages.
Thanks

There is a similar project going on that implements a robotic toolbox for matlab and python, it has "Rudimentary 3D graphics", but you can always interface it with blender with a well knit script, it will be less work than reinventing the wheel

If movements can be pre-computed, you can use Blender, hand-craft animations, bake them in some animated file format (cal3d ?), and just render in your wxPython OpenGL window.
If you need to handle user input, you can use a physics engine... I hear Bullet has Python bindings : http://www.bulletphysics.org/Bullet/phpBB3/viewtopic.php?p=&f=9&t=4030 (probably still unstable).
Regarding your doubts on Blender/OpenGL : What do you mean by "complex objects" ? How many "robots/whatever" ? How many triangle per robot ? How many articulations per robot ? (I'll edit my answer depending on yours)
Anyway, OpenGL in itself won't do anything else that juste "display triangles" ; everything else has to be done eslewhere.
EDIT
Sorry for the delay, I completely forgot.
So here is what I suggest :
Model your robot in Blender with polygons. You can easily go at >10k polygons, but try to keep the number of objects small (1 object per moving part)
Rig it, i.e. create a skeleton for it. You don't need to animate it.
Export as Collada or X3D
In your own OpenGL app, reimport
Draw your objects at the positions and orientations specified by the skeleton
Modify the angles between the bones just as you would do with real stepper motors
If step #5 was done right, robot should be follow the movements
Optionally add physics ( for instance with Bullet ). The API will be similar in concept to OpenGL, and you will be able to catch objects with your robotic arm.
good luck !

Can 3D OpenGL game written in Python look good and run fast?

I am planning to write an simple 3d(isometric view) game in Java using jMonkeyEngine - nothing to fancy, I just want to learn something about OpenGL and writing efficient algorithms (random map generating ones).
When I was planning what to do, I started wondering about switching to Python. I know that Python didn't come into existence to be a tool to write 3d games, but is it possible to write good looking games with this language?
I have in mind 3d graphics, nice effects and free CPU time to power to rest of game engine? I had seen good looking java games - and too be honest, I was rather shocked when I saw level of detail achieved in Runescape HD.
On the other hand, pygame.org has only 2d games, with some starting 3d projects. Are there any efficient 3d game engines for python? Is pyopengl the only alternative? Good looking games in python aren't popular or possible to achieve?
I would be grateful for any information / feedback.

If you are worried about 3D performance: Most of the performance-critical parts will be handled by OpenGL (in a C library or even in hardware), so the language you use to drive it should not matter too much.
To really find out if performance is a problem, you'd have to try it. But there is no reason why it cannot work in principle.
At any rate, you could still optimize the critical parts, either in Python or by dropping to C. You still gain Python's benefit for most of the game engine which is less performance-critical.

Yes. Eve Online does it.
http://support.eve-online.com/Pages/KB/Article.aspx?id=128

I did a EuroPython talk about my amateur attempts to drive OpenGL from Python:
http://pyvideo.org/video/381/pycon-2011--algorithmic-generation-of-opengl-geom
The latest version of the code I'm talking about is here:
https://github.com/tartley/gloopy
It's billed as a 'library', but that was naive of me: It's a bunch of personal experimental code.
Nevertheless, it demonstrates that you can move around hundreds of bits of geometry at 60fps from Python.
Although the demo above is fairly bare-bones in that it uses simply geometry and untextured faces, one thing I found is that more detailed geometry, texture mapping or other more modern graphics effects don't substantially affect the framerate. Or at least they don't affect it any worse than using the same effects in a C program. These are run on the GPU, so it doesn't make any difference at all if your program is written in Python.
One thing that is performance-sensitive from Python is if you are creating dynamic geometry on the CPU side, e.g. moving individual vertices within a shape, by bending or melting the shape. Doing this sort of per-vertex calculation in Python, then constructing a new ctypes array from the result, then shunting this geometry to the GPU, every frame, will be slow. Instead you should probably be doing this in a vertex shader.
On the other hand, if you just want affine transformations (moving objects around, rotating them, opening chests of drawers, rotating car wheels, bending a jointed robot arm) then all of this can be done by the GPU and the fact your program is written in Python makes little difference to the performance.

You might want to check out Python-Ogre. I just messed with it myself, nothing serious, but seems pretty good.

I would recommend pyglet which is a similar system to pygame, but with full bindings to OpenGL. You can start with simple 2D games to get the hang of the system and work up to 3D later. It is a more modern system than PyGame which is built around SDL which itself is a bit long in the tooth these days.

Perhaps a wee bit off topic but, if your goal is to learn Python, how about creating a game using IronPython and XNA? XNA is not OpenGL though, yet I find it an extremely simple 2D/3D engine which is fast and supports Shader Model 3.0.

Check out the Frets on Fire project -- an open source Guitar Hero alternative. It's written in Python and has decent 3D graphics in OpenGL. I would suggest checking out its sources for hints on libraries etc.

There was a Vampires game out a few years ago where most if not all of the code was in Python. Not sure if the 3D routines were in them, but it worked fine.

How to create a picture with animated aspects programmatically

Background
I have been asked by a client to create a picture of the world which has animated arrows/rays that come from one part of the world to another.
The rays will be randomized, will represent a transaction, will fade out after they happen and will increase in frequency as time goes on. The rays will start in one country's boundary and end in another's. As each animated transaction happens a continuously updating sum of the amounts of all the transactions will be shown at the bottom of the image. The amounts of the individual transactions will be randomized. There will also be a year showing on the image that will increment every n seconds.
The randomization, summation and incrementing are not a problem for me, but I am at a loss as to how to approach the animation of the arrows/rays.
My question is what is the best way to do this? What frameworks/libraries are best suited for this job?
I am most fluent in python so python suggestions are most easy for me, but I am open to any elegant way to do this.
The client will present this as a slide in a presentation in a windows machine.

The client will present this as a slide in a presentation in a windows machine
I think this is the key to your answer. Before going to a 3d implementation and writing all the code in the world to create this feature, you need to look at the presentation software. Chances are, your options will boil down to two things:
Animated Gif
Custom Presentation Scripts
Obviously, an animated gif is not ideal due to the fact that it repeats when it is done rendering, and to make it last a long time would make a large gif.
Custom Presentation Scripts would probably be the other way to allow him to bring it up in a presentation without running any side-programs, or doing anything strange. I'm not sure which presentation application is the target, but this could be valuable information.
He sounds like he's more non-technical and requesting something he doesn't realize will be difficult. I think you should come up with some options, explain the difficulty in implementing them, and suggest another solution that falls into the 'bang for your buck' range.

If you are adventurous use OpenGL :)
You can draw bezier curves in 3d space on top of a textured plane (earth map), you can specify a thickness for them and you can draw a point (small cone) at the end. It's easy and it looks nice, problem is learning the basics of OpenGL if you haven't used it before but that would be fun and probably useful if your in to programing graphics.
You can use OpenGL from python either with pyopengl or pyglet.
If you make the animation this way you can capture it to an avi file (using camtasia or something similar) that can be put onto a presentation slide.

It depends largely on the effort you want to expend on this, but the basic outline of an easy way. Would be to load an image of an arrow, and use a drawing library to color and rotate it in the direction you want to point(or draw it using shapes/curves).
Finally to actually animate it interpolate between the coordinates based on time.
If its just for a presentation though, I would use Macromedia Flash, or a similar animation program.(would do the same as above but you don't need to program anything)