I am working on a project where I have to render 4 different sides of a 3D object at the same time on the screen. The output should have 4 different camera outputs rendering the front side, left side, right side and back side of the 3d object.
I found that a gaming engine like Unity may help to do something like this. However, I have just started using Unity and can't figure out how to do it.
Here is the link for some examples. This is how I want the output to look like
Well first of all, welcome to Stackoverflow. And you are right, Unity is an excellent IDE to achieve what you described.
As stated in the FAQ and here, I'm going to give you an answer I deem fitting to your question. I can post the code here in about 30 minutes which does exactly what you asked for, but then we'd miss the point of learning to program and posting at StackOverflow in general. I'll show you the way on how to start on this project, but then you'll have to try yourself. If you have any troubles after trying some more, we can help you with specific problems, provided you have researched some before and show us what you tried.
As to your question, it's relative easy to do so. First create your object in the scene, then drag and place four different Camera-objects in the screen. Using the Camera's Normalized View Port Rect (Four values that indicate where on the screen this camera view will be drawn, in Screen Coordinates (values 0-1)), you can then split up the view to show the feed of each Camera.
This ofcourse happens in a script. You can read here about Scripting in Unity. Even if you are an expert in programming, that link is worth a read when you are new to Unity.
Good luck.
Related
See the picture below. It's a flash game from a well known website :)
http://imageshack.us/photo/my-images/837/poolu.jpg/
I'd like to capture the images, frame by frame, using Matlab, and then lenghten the line that goes from the 8 ball, the short one, so i can see exactly where it will go. And display another window, in which the exact pool table will appear but with longer lines for the paths :)
I know, or can easily find out, how to capture the screen and whatnot, the problem is that i'm not sure how to start detecting those lines, to see the direction they are heading towards. Can anyone suggest an idea on how to accomplish this? Any image processing techniques i could use to at least filter out everything except those lines.
Not sure where to even start looking, or for WHAT.
And yeah, it's a cheat i know. But i got programming skills, why not put them in practice? :D Help me out people, it's a fun project :)
Thanks.
I would try using the Hough transform in the Matlab Image Processing Toolbox.
EDIT1:
Basically the Hough transform is a technique for detecting linear structures (lines) in an image.
I'm completely newbie to Qt
i want to create a 800X600 window that just show some circle and be able to manipulate pixels of the form. there is no interaction between user and form(no click, no dblclick,...) it just shows some circles with one color and lines with different pixel colors(each line may have different pixel colors)
also i want to be able to change the coordination system, i mean change it from top-left to the center of the window. could anyone help me do that with some sample code?
thanks in advance for your reply.
Please try downloading the Qt Creator (IDE), then reading through the tutorials. There's a whole host of very useful information provided for free, including a lot of the code samples you are looking for.
The following examples might also be of particular interest:
Animation Framework Examples
Graphics View Examples
Painting Examples
I have a database of images of one person who is using his hands to show various words and phrases in sign language. The background is white and the only thing changing is the shape of the person's hands and their locations. Now in my gui in matlab, I want the user to be able to choose another image from the same person that was taken at another time doing a sign but wearing the same clothes and then the program will have to compare this against the images in the database and show the most similar. Obviously I can't do pixel by pixel comparison as the images were taken by a hand held mobile camera and slight movement has been inevitable so I should try and locate the hands in the images and compare their shapes. I have no idea how to go about this? I have to say I am new to image processing toolbox in matlab.
Your help is much appreciated
I am doing a phD in computer vision, and I can tell you that it is an unsolved problem. (even in your simple framewrok, with white background)
If you are interested, you might read some works about it ar MIT:
http://people.csail.mit.edu/rywang/handtracking/
or at Oxford:
http://www.robots.ox.ac.uk/~vgg/research/sign_language/index.html
http://www.robots.ox.ac.uk/~vgg/research/hands/index.html
I disagree with you. Such a project can achieve results quickly.
This becomes a problem as soon as the project has to deal with "real life".
Using a single camera, and a completely known background; Opencv provides a simple way to extract hand shape in a image (in about 20 lines of code). You will find plenty of source on the web (have a look at calcbackproj).
After that, what you will have to do is to play with shape, and search for characteristic points.
Begin with some simple signs (example : a circle and a V). How would you recognize one from the other?
There are thousands of papers on sign language; just read the older one to simple ideas flowing :)
I'm currently trying to write an app, that would be able to show the effects of glas, as seen through the iPhone Camera.
I'm not talking about simple, uniform glas but glass like this:
Now I already broke this into two problems:
1) Apply some Image Filter to the 2D-frames presented by the iPhone Camera. This has been done and seems possible, e.g. in the app: faceman
2) I need to get the individual lighting properties of a sheet of glas that my client supplies me with. Now basicly, there must be a way to read the information about how the glas distorts ands skews the image. I think It might be somehow possible to make a high-res picture of the plate of glasplate, laid on a checkerboard-image and somehow analyze this.
Now, I'm mostly searching for literature, weblinks on how you guys think I could start at 2. It doesn't need to be exact, in the end I just need something that looks approximately like the sheet of glass I want to show. And I'm don't even know where to search, Physics, Image Filtering or Comupational Photography books.
EDIT: I'm currently thinking, that one easy solution could be bump-mapping the texture on top of the camera-feed, I asked another question on this here.
You need to start with OpenGL. You want to effectively have a texture - similar to the one you've got above - displace the texture below it (the live camera view) to give the impression of depth and distortion. This is a 'non-trivial' problem, in that whilst it's a fairly standard problem in its field if you're coming from a background with no graphics or OpenGL experience you can expect a very steep learning curve.
So in short, the only way you can achieve this realistically on iOS is to use OpenGL, and that should be your starting point. Apple have a few guides on the matter, but you'll be better off looking elsewhere. There are some useful books such as the OpenGL ES 2.0 Programming Guide that can get you off on the right track, but where you start would depend on how comfortable you are with 3D graphics and C.
Just wanted to add that I solved this old answer using the refraction example in the Khronos OpenGl ES SDK.
Wrote a blog-entry with pictures about it :
simulating windows with refraction
In an application, i saw that they used to display pictures of vehicles. But what was amazing was when we touch and swipe in that picture, it rotates in 3d way left and right. And from the front view we can rotate and get to see its back view also. It is a very good feature and i was trying to replicate it. But couldnt get an idea of how and where to start. My doubts are
Whats the actual format of the thing, it surely isn't a picture.
How do they get to rotate it?
Could someone give me an idea where i should start or where I should look upon?
Just like the KennyTM told you, OpenGL-ES is the weapon of choice. Take pictures of that object from all the sides you need to show, then use those as textures for the faces of the cube. Got the idea?