I'm trying to research existing works in the area of recognizing complex graphical gestures, but struggling to find good search terms or clear documents in the field.
For example, I might want to recognize an arbitrary shape drawn by a mouse as a path, or a path with an arrow head, or an enclosed region, or some combination of various shapes. One of the problems I'm having is that the shapes are not necessarily going to take a consistent symbolic form, so I'm looking for alternate ways to represent the data.
This article has been helpful so far, but does not discuss any concrete algorithms.
http://www.springerlink.com/content/l4235612gv479262/
Anyway, I'm not necessarily looking for solutions here (though I'd be interested if there were some), but if people can help direct me towards some pertinent papers or the right kinds of search terms, I would appreciate it!
If you take the sequence in which the gesture is made/drawn into account then you might want to make use of sequence alignment techniques. Asking Google gives quite a few matches which you might want to explore.
Related
Is there a way to change the clutter perspective for a given container or widget?
The clutter perspective controls how all the clutter actors on the screen are displayed when rotated, translated, scaled, etc.
What I would really like to do is to change the perspective's origin from the center of the screen to another coordinate.
I have messed with a few of the stage methods. However, I haven't had much luck understanding some of the results, and often I hit some stability issues.
I know there are transformation matrices that do all the logic under the hood, and there are documented ways to change the transform matrices. Honestly, I haven't researched much further and just though I would ask for guidance before spending a lot of time on it.
Which leads me to another question regarding the matrices and transformations. Can one of these matrices be used to skew an actor? Or deform it into a trapezoid, etc? And any idea how to get started on that, ie. what a skew matrix would look like?
Finally, does anyone know why the clip path was deprecated? It seems that would have worked for what I ultimately want to do: draw irregular shaped 2d objects on the screen If I can implement an answer to question 2, then I guess a clip box with a transformation can be used here.
1, I do not know if (or how) one might change the Clutter stage's focal point.
2 A skew or shear transformation matrix is easy enough to construct, and can be implemented in the GJS Clutter functions Clutter.Actor.set_transform(T) and Clutter.Actor.set_child_transform(T) where T is a Clutter.Matrix .
This does present another problem, however, for the current codebase; and this leads to another question. (I guess I should post it somewhere else). But, when a transform is set on a clutter actor (or its children), the rest of the actor's properties are ignored. This has the added effect that the Tweener library cannot be used for animation of these properties.
3 Finally, one can use Cairo to draw irregular shaped objects and paths on a Clutter actor, however, the reactive area for the actor (ie. mouse-enter and -leave events) will still be for the entire actor, not defined by the Cairo path.
I can't find a working example of a cutting plane implementation for HelixToolkit.Wpf.SharpDX.
I hope to achieve something simpler than the HelixToolkit.Wpf cutting plane which can be invoqued by shift+clic anywhere on the displayed model.
I'll be happy if at least I would be able to do cutting planes with axis-oriented normals, I don't have any interest in custom oriented cutting planes.
Edit
After answering to first comment, I add the precision about trying to do something after the CrossPlaneSection example from the github, but couldn't find someting to use on a more complicated scene. Still waiting for tips.
See the cross section example in Sharpdx version
https://github.com/helix-toolkit/helix-toolkit/tree/develop/Source/Examples/WPF.SharpDX/CrossSectionDemo
I would like to use D3 to build simple charts with literally hundreds of millions of data points.
Obviously, I won't be attempting to plot millions of points at a time. Only a very, very tiny fraction of those points (<1000) would be in view at any given time. I'll download pre-processed data "on-demand" from the server depending on the current view and zoom level, and would like to use D3's built-in zoom and pan behaviors.
Basically, imagine an infinitely wide bar chart that pans back and forth, and alters itself to show the appropriate level of detail depending on the current zoom level (e.g. semantic zoom).
What techniques are available in D3 to achieve this, yet still have it feel responsive and smooth? What should I avoid doing? Are there any examples of this out there?
Examples: Have a look at Fabian Fischer's BankSafe, an award-winning entry to this year's VAST Challenge. Not sure if the code is available, but the report summarising the techniques he used certainly is. The dataset was also in the order of "hundreds of millions" and - if I remember correctly - had a zoom technique similar to the one you describe.
I would highly recommend you look into using canvas over svg. From what I've seen, having thousands of SVG elements doesn't scale particularly well. Microsoft has a pretty good writeup for how to know which to choose: http://msdn.microsoft.com/en-us/library/ie/gg193983(v=vs.85).aspx#Using_Canvas_AndOr_SVG
I am trying to create a bounding box around each character in an image. I have converted the image to binary and thresholded it but I don't understand how to create a bounding box despite reading the manual.
There are a few options for the bounding box technique, but I think you'll get a great result combining these two:
First, use the technique demonstrated here to detect a large portion of text and put a bounding rectangle around it so you crop the image to this area;
Second, experiment with the technique recently presented by OpenCV, also demonstrated here. It could be used to locate/extract individual characters on the resulting image of the first step.
I suppose you are trying to implement the OCR mechanism yourself instead of relying on great APIs such as Tesseract.
If you are looking for more information on how to do digit/text recognition, check this answer.
As said before "rudely", I encourage you to rewrite your question with more detail on what you already did. We didn't understand what you would like to do. If character recognition is what you want, have a look at this.
There are so many easing functions available in Expression Blend, and so many settings on each, it is often hard to know instinctively what easing function to choose. Trying all the options would take quite a long time.
In this instance, I want to give the impression that the item has fallen forward and down. I am using a projection rotation about X and currently using one of the circular easing functions, but it does not feel quite right. A subtle bounce would probably help.
What would be the best option (and specific settings) to give the impression of falling a short distance?
As always, thanks in advance.
Follow-up: After the comments below and as a potential long-term solution to the general problem posed here (choosing easing functions and settings by keyword), we have now setup www.easing.co. We will be seeking contributions from the community, so if you are interested in helping with the project, drop us a line via that website only.
I came across this post whilst looking for an answer to the same question.
I Used a 'BounceOut' ease with 2 bounces, and a bounciness of 10.
Pete