In my application in Windows Phone, i have made a custom plotting library for some simple plotting of a graph. I did this, using System.Windows.Shapes. Now i run to some problems when i want to use this on other platforms (android, and iphone, using mono).
So i came to the conclusion that i may need to remake te library using System.Drawing only. Because that namespace is available on all three platforms, and (if i have googled correctly) contains some functionally in drawing stuff on ui's.
My Questions
Am i correct in the fact that drawing contains drawing functions.. If so, how do i make a multi point line or polyLine?
Are there any (allready available) libraries that do the same using the System.Drawing namespace only?
If there are any plotting libraries that are available for only Android an MonoTouch than that will do aswell, because i've allready got a graph drawing function on my windowsphone, This will be my last resort. Because i want to keep the code behind the platforms mostly the same.
What i found out:
After some time put in to searching for an answer for this, i gave op hope to find libraries that implement a graph functionality for all the three platforms. There just doesn't seem to be one. There are libraries available for Silverlight and Monotouch(IOS) but, the silverlight part is NOT compatible with windows phone.
I found out that the library system.drawing does not have full functionality in silverlight, so after some careful consideration I also stepped away from that idea. And Moved towards making my own library that implements some #if (SILVERLIGHT) or #if (MONOTOUCH) region functionality.
At this point i have made my own library for WindowsPhone being able to draw a decent plain and simple graph. I eventualy done this using the System.Windows.Shapes namespace. Today i will start making the same sort of lib for android. And after that i will do it for windowsphone, The library will be open source, and when finished i think i will release it somewhere.
As a sort of summary: "there was not a real answer to my question, so
i had to work around it. This work around made me make my own cross
platform library
".
Related
I need a C++ library that runs on Android and iOS which can be used to create PDF documents.
So far I have found libHaru:
libHaru is a free, cross platform, open source library for generating PDF files.
The library seems fine and I already found a working example on how to use it with iOS.
But I would like to have a library less "low level", because in libHaru you have to manually create new pages, line breaks etc. So the question is if someone can advice me any C++ library which can run on Android and iOS and is a little bit more high level.
As a bonus: It would be great, if that library is also free (as in freedom) or at least free to use.
Edit: I have tried Qt and it is rather clumsy to use in such an early development stage (regarding iOS and Android development). I would appreciate a stable library with good documentation provided.
You can use Qt for that. The class you would be looking for is QPdfWriter The nice thing about it is, that as you draw onto that thingy, you can replace the QPdfWriter with different kinds of QPaintDevices, like QWidget or QImage and so forth. It's very generic and high level, but Qt is also quite big.
I've been developing a game recently and I would like to incorporate pixel perfect collisions (so it ignores the alpha part of the image)
After doing some research I was referred to using the software PhysicsEditor for you to create unique bodies to use in box2d:
http://www.codeandweb.com/physicseditor
the software itself is fine to use and I've got all .xml files ready to use and everything in my project set up
I've also been looking at the examples provided here:
https://github.com/ANDLABS-Git/AndEngine-PhysicsEditor-Extension-Examples/tree/master/src/org/andlabs/andengine/extension/physicsloader
My problem is I'm not entirely sure where to go from here to begin to detect collisions - I understand how basic box2d collisions work but I have no idea how to use anything created from PhysicsEditor
I'm very new to android programming so I don't quite understand how to use PhysicsEditor in my project and how to use what it's created as bodies that can be attached to sprites and such - (unless it's all included within the loader it's self?)
After I've used the loader (as seen in the example) - what do I do from here?
I can't seem to find any other examples of people using the PhysicsEditor with collisions in their project either so I'm stuck on what to do.
(I've also looked up other alternatives for perfect pixel collisions but they seem even more of a hassle to set up)
Any help would be appreciated and an example of a basic project using PhysicsEditor with collisions or some sort of tutorial for dummies would be ideal.
Thanks
I created an Android app. While creating one specific app was an interesting challenge, I'm now looking into creating a group of similar apps.
I'd like to create a group of similar Android apps and then move on to creating the same on tablets and iOS... (anything mobile).
I've considered doing so with a product called PhoneGap or doing a web based mobile app. Both of these options seem less than ideal. Doing the Android app I've been frustrated by Java's lack of control and low level constructs. Moving to something like a web based app seems like the exact wrong direction.
C++ is my language of choice. It has the ability to work at a low level, is highly portable across platforms, and has significant support for generic coding which would be useful for generating a group of similar apps. However, the Android documentation suggests to not use C++ unless your goal is porting existing code or dealing with computationally heavy tasks.
I'm leaning towards using C++ anyway, but are there other options I've not considered?
Thanks
You could in theory write your logic in C++ and then have UI layers on top that make use of it. If you are really comfortable with C++ that might be the way to go.
Almost any other parts (networking, UI, animation, etc) are better off being done in the native language of the platform. Use of cross platform solutions always limits you in some way, and usually leads to an application that is not as good as it could be for any platform.
Well, Google's recommendation to not use C++ is based on the following, I believe. C++ is low level, so you can get extra performance out of it if you know what you are doing. Google makes the reasonable assumption that many programmers do not. It is easier for an inexperienced programmer to do harm in C++ then to get a performance boost.
But, if you know what you are doing, it can help you. UI elements on both iOS and Android are implemented in their main language (obj-c, and Java respectively) so there is not a great way around that, but you can write core logic and other functions in C++ and it will be portable between them (iOS can use C++ directly and Android can use it via the Native Development Kit).
There are a few other options available. The one I ended up using is Appcelerator Titanium but please stay away from it. If your project gets complicated or large at all you will hate yourself for choosing it, as I did. Another interesting one that uses C++ instead of Javascript is Marmalade. I haven't used it though, so I can't comment on it.
A non-free solution that I hear good things about is Xamarin, who have ported both environments to C# and a .NET using Mono. However, you still have to write two versions of your code for the UI as far as I can tell.
I'm not sure if this is the best place to ask this question so if it isn't please let me know and I will move it. I am looking to create a game for both Android and iPhone platform. I know Unity is a great game engine and my question is how well does it work for creating one code base to build for both Android and iPhone platforms? Time is a constraint on this project so I am very interested in how smoothly the process usually is when trying to build both applications and how much custom code must be written for each specific application. Any insite that people have on this topic would be much appreciated thanks.
Unity, as implied by it's very name, is designed explicitly to facilitate such multi-platform development in little time. You can for example define for each platform what the max size of each texture is, and it will automatically resize them for you when you build for that target platform - the build process really simple too. Since both your platforms are touch devices, it should be easy to have just one code base working seamlessly for both platforms (and more if needed), with very few custom code for each platform.
Unity has a no-questions-asked 30 day trial of the Android and (I think) iOS versions - I encourage you to try them and see for yourself how little time it will take you to have a proof of concept build for both platforms.
I was using opencv for some time for programming in Android, and I now see that the Gimp library is much stronger. Where can I find a starting point to learn Gimp?
I also want to know the basic concepts behind of Gimp plugins. In the past, I used C APIs in opencv. How could I write the code for android?
Also, what packages do I need to install in windows to start using Gimp?
ALthough GIMP dows have some standalone libraries that perform some image manipulation, most image manipulation is done either by GIMP's core program or through GIMP's plug-ins. Both approaches need to have the entire program installed and running (though not necessarily usin a display).
I know nothing on Andorid progrmaing, and don't knwo how can one install ordinary native code in C and call it from Android apps - if you are very familiar with it, you might have a chance in your attempt.
However GIMP itself relies on a extensive ecosystem of libraries, including, but not limited to, glib, gtk+, cairo, pango, gegl - and each of these in turn might have other pre-requisites. Since Windows does not have a working package manager to authomatically install libraries and header files of these various libraries, working with these natively on Windows, though the code of each of them is multiplatform and can run on Windows and other OSses,is very hard. So hard that hthe people who build GIMP for Windows themselves do so in a Linux environment, from where they cros-compile GIMP for Windows.
Making all of these libraries work on an Android is probably not hard if you are using the GNU ecosystem around the Android's Linux kernel , and not just the bare Android environment (I don't know enough about android to even know if that is possible).
All in all: it will be though for you, and demand a whole lot of research.
One of GIMP's libraries, the GEGL (Generic Graphics Library) has a lot less prerequistes, and can be used as an ordinary library. I think you can probably build it with just glib and Babl as prerequisites. This is the library that will replace current's GIMP core, and reimplement the operations of most existing plug-ins -- so it might be enough for you.
If you can get GEGL running and usable from an Android system share that with the World --it would be , in itelsef, a project worth of a Google Summer of Code project. (And still would be about an order of magnitude easier than getting GIMP code in there to be used as a library from other applications).
Finally -- if you want just a couple of GIMP's effects, if the effect is implemented as a Plug-in in GIMP, the plug-ins' code is quite straightforward. So, while it would be hard to get the whole GIMP environment inside Android, copying the functions that actually perform the pixel manipulation from GIMP's source tree and converting them to work in a java method inside your app would not be hard. Just remember to comply with the license in this case: GIMP's plugins code is under GPLv3. (the GEGL library is only LGPL)
In short: no, you can't use GIMP's "libraries" as native code from an Android app -if you can use OpenCV, you have a good chance of being able to use GEGL instead. Only orting the algorithms of certain plugins to manipulate pixels in your app would be easier.
However -- if your application would allow delegating Image Processing to an internet based server, setting up an HTTP application to receive a image, use GIMP to process it, and stream it back would be a simple thing to do.
(So, you could not apply effects in real time, but would allow one to, for example, take a photo, select a series of effects from menus, and send it to the server for processing)
GIMP uses quite a bit of memory when loading brushes. If you drop all of the useless plug-ins, and build it from source. You may be able to get it working but you will have to build ALL of the linked libraries directly into the executable.
In other words; build linked libraries directly into the code as a static build. In this manner things may function properly unless one of those linked libraries call another linked library.
Getting the libraries themselves to work on the OS may provide additional programs opportunities to use them. Additionally, GTK+ (GIMP Tool Kit), GIMP's interface is also rather bloated and ugly.
If all else fails, you'll simply have to settle for a smaller program with the features you're looking for on the fly ( Levels, Curves, the clone tool, dodge and burn, etc. ) Layers are also nice, but editing a a large megapixel image begins to eat up memory rather quickly and most android device don't have a swap partition.