How to scale a Kinect Skeleton to match to other Kinect Skeleton - kinect

I have some saved skeleton data, the data corresponds to my own skeleton proportion, lets call this skeleton Sk1.
And i have other skeleton data (that corresponds to a ten old year child, by example). lets call this Sk2.
I want to scale one skeleton size, to another skeleton size, mantaining the proportions.
PS: I know the ScaleTo() extension method os Coding4Fun library but i dont understand this method in deeply.
How can i achieve it?
EDIT 1
Tha ScaleTo() extension method from the Coding4Fun did not work for me.
So i am trying to implement my ow scale method to scale the entire skeleton, please refer to this question for the actual code

Related

First-person game in OpenGL ES 2.0

I know I need to use a frustum projection for a first-person game I'm writing. However, I'm not sure what the most efficient way to move around in the world is.
Currently I'm using
Matrix.setLookAtM(mVMatrix, 0, eyex, eyey, eyez, lookx, looky, lookz, upx, upy, upz);
Matrix.multiplyMM(mMVPMatrix, 0, mProjMatrix, 0, mVMatrix, 0);
every time the display is redrawn. User input changes the "eye", "look" position vectors, and the "up" direction vector.
However, I've read elsewhere that one should tranlate/rotate the world and not the "camera".
My question is: should I rotate the objects about a fixed "camera" (i.e. only use setLookAtM once at set up) or should I carry on using my current method?
There is no such a thing called as camera in OpenGL. In fact, what you describe by moving the objects instead of the viewpoint is what Opengl actually accomplishes internally to give you the feeling that camera moves. There is a great article along with a tutorial that describes all about cameras on OpenGL ES 2 and basically it is the same logic on other versions:
http://db-in.com/blog/2011/04/cameras-on-opengl-es-2-x/
It might seem boring and confusing but I have been searching about cameras on OpenGL ES 2 a lot and this article is almost perfect for a beginner.
To answer your question, your current method is exactly the same that you are describing. The camera is always fixed in OpenGL and what you do with matrix multiplications provides you the effect that you want already. When you multiply your model matrix with view matrix and projection matrix, in the end, you define a new position for your object depending on your camera parameters.

How to map kinect skeleton data to a model?

I have set up a Kinect device and written a simple program that reads the stream to a QImage using OpenNI 2.0. I have set up skeleton tracking with NiTE 2.0, so I have access to the coordinates of all the 15 joints. I have also set up a simple scene using SceniX. The hand coordinates provided by the skeleton tracking are beeing used to draw 2 boxes to represent the hands.
I would like to bind the whole skeleton to a (rigged)model, and cant seem to find any good tutorials. Anyone have any idea how I should proceed?
depending on your requirements you could look at something like this for Unity Engine https://www.assetstore.unity3d.com/en/#!/content/10693
There is also a Plugin for the Unreal 4 Engine called KINECT 4 UNREAL FROM OPAQUE MULTIMEDIA
But if you have to write it all by hand for yourself, i have done something similar using OpenGL.
I used Assimp http://assimp.sourceforge.net/ to be able to load animated Collada models and OpenNi with NiTE for skeletal tracking. I then used the rotation data from the Nite skeleton and applied it to the corresponding Bones of my rigged mesh, overwriting the rotation values of the animation. Don't use positional Data. It will strech your bones and distort the mesh.
There are many sources for free 3D Models, like TF3DM.com . I for myself used a custom Rig for my models to be suitable for my code. So you might look into using Blender and how to Rig a Model.
Also remember that the Nite Skeleton has no joint for the Pelvis, and that Nite joints don't inherit their parents rotation, contrary to the bones in a rigged model.
I hope this helps to have something to go on.
You can try DigitalRune, they have examples of binding a rigged model to joints. They have mentioned some examples too. try http://www.digitalrune.com/Support/Blog/tabid/719/EntryId/155/Research-Augmented-Reality-with-Microsoft-Kinect.aspx
Also you would need to know to animate model in blender and export it to XNA or to your working graphics framework. Eg:-http://www.codeproject.com/Articles/230540/Animating-single-bones-in-a-Blender-3D-model-with#SkinningSampleProject132

Kinect: How to obtain a skeleton from back view?

Why should you ever want something like this?
I want to track a single user that is mounted above the ground in a horizontal position. The user is facing downwards to allow free movement of legs and arms. Think of swimming for example.
I mounted the Kinect at the ceiling facing downwards so I have a free view of all extremities.
The sensor is rotated 90° in z-axis to have the maximum resolution (you're usually taller than wide).
Therefore the user is seen from the backside, rotated by 90°. It is impossible to get a proper skeleton from OpenNI 1.5. My tests showed that OpenNI is expecting the user facing the camera with the head up in y-axis (see my other answer). Microsofts SDK is the same but I excluded it here because it won't allow you to change the source code and cannot be adapted. OpenNI 2.0 is not working with the current SensorKinect to interface the Kinect in Linux. So:
Which class is generating the skeleton in OpenNI 1.5.x?
My best guess would be to rotate the prototype skeleton by y 180° and z 90°. If you know where I could find this.
EDIT: As I just learned there is no open source software that generates a skeleton from depth images so I fall back to the question in the header:
How can I get a user skeleton from a rotated back view?

Improve perfomance of my threejs

I have some issues about my model. Is is an easy model buy I can not make It work well...
I upload my project here: http://webgl.drapps.info
I have a car model with some pieces that change material when mouse is over them. I use threex.domevent.js library with "on" function. My model is loaded by json files.
Issue 1
when mouse is out of canvas, threejs detects that mouse is over a piece of my model, but this is not true, and that piece change its material (triggering mouseOver event).
Furthermore, I tried to get better mouseover event because even when mouse is really over a piece, that event doesn't trigger.
Issue 2
This is about TrackballControls. Is there any way to control rotation of my world? I mean: rotation only in one axis, rotation only for 180 degrees, etc... Is there any tutorial or article to learn how to rotate and translate camera?
Thanks for everything, I will so please to anybody who wants answer this... because I am a little lost
Thanks
Sorry, but you are out of luck.
Question 1. Yikes! You are using threex.js which is a third-party app that hasn't been updated in almost a year, so I can't help you with that.
You are also using an older version of three.js. Please update to the current version.
If you still have problems, post a new question with a simple demo -- not your entire project. Better yet, Google your question first.
Question 2. TrackballControls is not part of the library -- it is part of the examples -- so it is not officially supported. If you are not happy with it, you will have to hack the code yourself.
This question has come up a lot. Google it. To the best of my knowledge, there is not a good solution.
Personally, I would use OrbitControls in your case -- it keeps the scene right-side-up, and you can constrain the maximum polar angle, keeping the camera "above ground".
The best examples/tutorials are the official three.js examples, which will work with the current version of the library.
I can't help with issue 1.
Issue2:
I am also working on a project to visualize vehicles and needed to be able to rotate. I also tried Trackballcontrolls but it did not suit my needs.
What I ended up doing was creating a a master Object3d and then instead of adding objects/models to the scene, I added them to the master Object3d. That way to rotate everything in the scene, I just had to rotate the master object.
To actually do the rotation I just used the code from one of the cube examples.

Is it possible to animate markers in ArcMap?

I'm completely new to ArcGIS and ArcMap, but someone suggested this program to me for a project I'm working on.
I would like to animate individual entities on a map, and was wondering if it is possible to do so in ArcMap. I asked this earlier here and a member directed me to a tutorial on animating in ArcGIS. The animation in the guide was over a map spread (ie. each pixel on the map displays, say, a different color to indicate population data in the area). However I realized that if I zoom in a lot, eventually the image will degenerate into pixels, which is why I need an actual object to mark a certain point. I checked some online tutorials and it seems like we can place markers on the map. Can someone tell me if it is possible to animate these markers (for example via a for-loop)? And if so, could you point me in a direction where to start?
Thanks in advance!
You can animate layers in ArcMap is the short answer. Its not as simple as using the timeline feature in Google Earth for example though. But then ArcMap is much more than just a visualization tool.
This help page on the ESRI web help looks like a good place to start.
I'm not 100% sure what you mean by the image degenerates into pixels. Are you saying that the markers were single points in the layer. Unlike Google Earth you are not confined to simply plotting points on the map. You can draw completely arbitrary shapes in ArcMap, which can be defined to cover actual areas of the map, so when you zoom-in the shape gets larger.
The way you need to load data into ArcMap to produce an animation isn't too simple. There might be other ways to do this, but the way I know of is to generate a NetCDF file. This file contains a 3D matrix of layer data, where each layer is separated through time. Because you generate a matrix, you are effectively placing a raster image over the map. Thus if you want to cover a large area, each matrix becomes large, and you multiply that by the number of time slices you wish to animate over.
Once you have a NetCDF file with your data in however, getting ArcMap to animate it and produce say a .avi file is pretty simple.
You could try just loading some of the example NetCDF datasets into ArcMap to see how/if they will work to get you started.
Hope that helps.
The upcoming v10 will have better time-aware capabilities, which will allow for animation.