Posts Tagged ‘Programming’
Programming related posts.
Unity: Scaling the GUI based on the screen resolution
Posted by Dimitri | Filed under Featured, Programming
As hinted by other posts, here, you will find how to properly scale the GUI elements based on screen resolution. As one may have noticed, Unity doesn’t scale the GUI elements based on the screen resolution, requiring a script to do the job, which is explained in this post. I will assume that the reader already knows how to create and render GUI elements in Unity using the MonoBehaviour’s OnGUI() function and GUISkin objects.
The best way to explain how to properly scale a GUI element is through an example. That said, for this post, let’s assume that we wanted a yellow rectangle to be rendered at the top left and bottom right corners of the screen, like this: (more…)
Android: take a picture without displaying a preview
Posted by Dimitri | Filed under Programming
Accessing hardware functionality when programming for an Android device is generally quite straightforward. The same can be said about writing an Activity that takes a picture, but Android requires a preview of what the camera will capture to be displayed prior to capturing an image. This post explains how to “cheat” this requirement imposed by the OS, and how to write an application that takes a picture and displays it.
An Eclipse project with all the code explained here is available for download at the end of the post.
Before going into the Activity code, the interface layout (the main.xml file) must be edited to add a Surface View and an Image View to the interface. To add an element, just drag and drop it from the list inside your layout, like this: (more…)
Android: Acessing the gyroscope sensor for simple applications
Posted by Dimitri | Filed under Programming
This post explains how to get values from the gyroscope (or any sensor that returns the device’s relative angle) to create simple application. The reason why I’m stating ‘for simple applications’ is because the code featured here is already deprecated. I’m just explaining how to do it because it still works, and it’s very clean and short to explain, as opposed to the new method, which is much more accurate but more complex to implement.
Still, it’s possible to use it for simple applications, although, if the application requires accuracy from the sensors, such as augmented reality applications or even games, it’s recommended to use the getRotationMatrix() method from the Sensor Manger class instead.
With that said, the following code just prints the rotation values from the gyroscope on the screen: (more…)
Android: How to return RGB values from an image file
Posted by Dimitri | Filed under Programming
Surprisingly, it’s quite easy to get the RGB value from an image file in Android. It’s certainly a lot easier than retrieving the pixel values from the Camera Preview. All that is required is to load the image file into a Bitmap object and them call the getPixel() method from the loaded bitmap.
It’s also possible to call this method to create an array of alpha and RGB values (ARGB) without calling the copyPixelsToBuffer() method, avoiding the use of buffers in Android which make things more complicated than it should be. As an example, the following code prints the color values of the pixels from the 4 corners of the image in LogCat and creates a RGBA array that stores each pixel color value:
Android: Retrieving the Camera preview as a Pixel Array
Posted by Dimitri | Filed under Featured, Programming
This post explains how to take the live images created by Android’s camera preview feature and return them as a RGB array, that can be used to all sorts of things, like custom effects preview and real-time image filtering. This post used the CameraPreview class that already comes bundled with Android’s SDK because it has everything already set-up, that way is just a matter of inserting more code. The techniques shown here works with Android 2.1 and should work with versions 1.6 and 1.5.
The first thing to do is to import the API Demos project to your Workspace. To do that, in Eclipse, click File -> New -> Android Project. In the dialog that has just opened, give the project a name at the first field (like API Demos 8) and select ‘Create project from existing source’. Now browse to <Android SDK folder>\samples\android-7\ApiDemos. Finally, mark Android 2.1 as the Build Target and click Finish: (more…)