I have been tasked with making several flex-driven visualizations of immense excel spreadsheets. The client wants the finished product to be as self-contained as possible. The problem being that flex doesn't offer as much computing horsepower as is needed. Is there an easy (or not easy) way to accomplish this. I am just trolling for pointers. Thanks in advance!
If you dont mind doing it the hard way, I have two options for you:
Pixel Bender: a tool originally designed for creating complex and CPU-intensive graphic filters and offload those calculations to the hardware. But it can be used for number crunching too. Here's an article that covers that topic: Using Pixel Bender with Flash Builder 4 as a number crunching engine. The language may not be like anything you're used to. I had a hard time wrapping my head around it.
Alchemy: a tool that compiles C or C++ code so it can be executed in the Flash VM. I am not certain how much performance can be gained for simple number crunching, but if you know C, this might be a path to investigate.
The first thing that comes into my mind - building a webservice that will do the hard work. But this is not a self-contained product though.
Apart from that - take a look at the apparat - http://code.google.com/p/apparat, it allows various optimizations, access to the low level AVM2 code - http://code.google.com/p/apparat/wiki/AsmExpansion and more. I do not think that as3 and flex compiler is so bad for math. Try to write the sample math function and test it using different languages.
Related
The QT dev kit comes with some good examples of how to code features via trivial apps, but nothing comes close to showing how to structure a complex program in QT. What, if anything, should be global, etc? Pitfalls in designing your classes that would turn out to need a lot of eventual refactoring?
I'm sure there are plenty of open source KDE apps that would serve nicely, so I guess my question is what't the minimal amount of source code I'd need to download and set up in order to work with, say, Dolphin as a sample app? If the answer is 'all of KDE', then I guess this isn't practical (unless downloading and building all of KDE from source is easy enough to make that practical).
Any suggestions? Personally, I'm looking to build a browser-like app, but much simpler. So for an example to follow, something that handles sockets and multiple tabbed viewports would be nice.
Thanks,
Rob
The main advice regarding Qt itself is I would give is to try to spend as much effort as possible in learning to use Qt's Model View Delegate functionality. It can be a lot of work to wrap your head around, but once you get there, you can do very powerful things with it. Another relatively tricky topic you will want to invest learning resources in is memory management and how Qt facilitates (and doesn't facilitate) it.
One of the most confusing things to me was though that when your model is very complex, you might not want to have your core model class be a Qt model at all. Instead, I nowadays see Qt models as something that primarily provide data to views. If your model is very complex, you might want to use your actual, more complex model as a data source for the Qt model class (an QAbstractItemModel derivative), which in turn attaches to the UI view.
Also, Qt documentation is your friend. Qt is a wide framework and contains LOTS of useful functionality. I love the data structures in their ease of use, for example: QHash, QList, etc.
Project scaffolding features for beginners, for different project types in Qt Creator might indeed be useful. For now, the Qt Examples actually are quite good ones, and contain lots of good practices. You just need to pick and choose what you need.
I have been developing our Qt desktop app family for five years now. Our directory structure is quite unorthodox - the main thing is that we have lib/ under which we have grouped different related functionality in subdirectories. The thinking goes, if something is in lib, it is general-purpose and atomic enough to be used in several of the actual desktop applications in our software family.
Your question seems more general level than Qt. It is difficult to tell if you are looking for a more general level computer science education. Globals in general should be avoided, sure. OTOH, we do have a constants.h and other immutable configuration data that is global-like, since it is needed in many places. This adds state though, so it can have unpredictable consequences if you don't do it carefully.
You could look for directory structures in places like this, though I don't really follow this advice myself. http://hiltmon.com/blog/2013/07/03/a-simple-c-plus-plus-project-structure/
Unless you are planning to contribute directly to KDE, I would advice against learning KDE way of doing things. Not necessarily because they are doing things badly, but because it is a world of its own - the best practice for KDE development might not be the best practice for a stand-alone Qt app. (Disclaimer: I, as a UI developer, don't actually like KDE, so I do not know the project very well - aside from the fact that it indeed seems a bit monolithic to the outsider.)
So I wonder if something like Qupzilla would fit the bill for you? (Found via qt-apps.)
HTH.
I am currently considering writing a small game. It is essentially a map where you can zoom out and in, and in certain places click on info boxes where, at some point, I hope to integrate minigames. Granted, game might be overstating it. Think of it as an interactive map. The theme is how mathematics can be applied in peoples every day life to raise awareness on the usefullness of mathematics.
The question is how I as fast as possible can make a reasonable prototype. If I recieve enough positive response on this I might try to code "the real thing" and use the prototype to obtain funding.
However, I am at a crossroad. I want something to work rather fast and have some C++ experience coding optimization problems, mainly in c-style. I am not convienced, though, that coding it in C++ is the fast way to obtain a prototype. Though I have some experience coding in C++, but have no experience in coding any sort of GUI.
As I see it there is a number of possibilites:
C++, possibly using some library, such as boost or ???.
Start out purely webbased, using e.g. HTML 5 and java.
Python
C#/.NET
Others, such as?
I have to admit I have little experience with anything besides C++ and the STL.
So my question to this wonderful forum is basically, is there a language that provides a significant advantage? Also, any additional insight or comments is more than welcome!
Python is a simpler language than C++, and for prototyping it will help you focus on the task at hand. You can use Pygame, a game library built on the excellent cross-platform SDL library. It provides 2D graphics, input, and audio mixing features. SDL is mainly a C library (and thus compatible with C++), and there are a number of very useful libraries that integrate with it:
SDL_image for loading images in various formats
SDL_ttf for rendering text using TrueType fonts
SDL_mixer for audio mixing
SDL_net for networking
SDL_gfx for graphics drawing primitives
So if you prototype in Python using Pygame, there is a reasonable chance you’ll be able to port what you make over to C++ with minimal hassle, if and when you choose to do so.
Possible options:
Go with what you know the best. Anything else will require a learning curve, which may be weeks to months long. If you're willing to take that road in order to make your prototype, then there are some really great tools available.
BlitzBasic is a good way to go, and is basically designed to be for games
I've done little games in Java using Slick2D - but you'll need good grounding in object-oriented coding to work effectively in Java. If you've got that from C++, then you can see a tech demo I built in Slick2D called Pedestrians. It's open source, and has demo videos here.
You might also ask your question on https://gamedev.stackexchange.com/ - a Q/A site dedicated to game programming
The other day i stumbled onto a rather old usenet post by Linus Torwalds. It is the infamous "You are full of bull****" post when he defends his choice of using plain C for Git over something more modern.
In particular this post made me think about the enormous amount of abstraction layers that accumulate one over the other where I work. Mine is a Windows .Net environment. I must say that I like C# and the .Net environment, it really makes most things easy.
Now, I come from a very different background made of Unix technologies like C and a plethora or scripting languages; to me, also, OOP is just one, and not always the best, programming paradigm.. I often struggle (in a working kind of way, of course!) with my colleagues (one in particular), because they appear to be of the "any problem can be solved with an additional level of abstraction" church, while I'm more of the "keeping it simple" school. I think that there is a very different mental approach to the problems that maybe comes from the exposure to different cultures.
As a very simple example, for the first project I did here I needed some configuration for an application. I made a 10 rows class to load and parse a txt file to be located in the program's root dir containing colon separated key / value pairs, one per row. It worked.
In the end, to standardize the approach to the configuration problem, we now have a library to be located on every machine running each configured program that calls a service that, at startup, loads up an xml that contains the references to other xmls, one per application, that contain the configurations themselves.
Now, it is extensible and made up of fancy reusable abstractions, providers and all, but I still think that, if we one day really happen to reuse part of it, with the time taken to make it up, we can make the needed code from start or copy / past the old code and modify it.
What are your thoughts about it? Can you point out some interesting reference dealing with the problem?
Thanks
Abstraction makes it easier to construct software and understand how it is put together, but it complicates fully understanding certain issues around performance and security, because the abstraction layers introduce certain kinds of complexity.
Torvalds' position is not absurd, but he is an extremist.
Simple answer: programming languages provide data structures and ways to combine them. Use these directly at first, do not abstract. If you find you have representation invariants to maintain that are at a high risk of being broken due to a large number of usage sites possibly outside your control, then consider abstraction.
To implement this, first provide functions and convert the call sites to use them without hiding the representation. Hide the data representation only when you're satisfied your functional representation is sufficient. Make sure at this time to document the invariant being protected.
An "extreme programming" version of this: do not abstract until you have test cases that break your program. If you think the invariant can be breached, write the case that breaks it first.
Here's a similar question: https://stackoverflow.com/questions/1992279/abstraction-in-todays-languages-excited-or-sad.
I agree with #Steve Emmerson - 'Coders at Work' would give you some excellent perspective on this issue.
I used to play a MUD based on the Smaug Codebase. It was highly customized, but was the same at the core. I have the source code for this MUD, and am interested in writing my own (Just for a fun project). I've got some questions though, mostly about design aspects. Maybe someone can give me a hand?
What language should I use? Interpreted or compiled? Does it make a difference? SMAUG is written in C. I am comfortable with a lot of languages, and have no problem learning more.
Is there a particular approach I should follow to not hinder performance? Object Oriented, functional, etc?
What medium should I use for storing data? Flat files (This is what SMAUG uses), or something like SQLite. What are the performance pros/cons of both?
Are there any guides that anyone knows of on how to get started on a project like this?
I want it to scale to allow 50 players online at a time with no decrease in performance. If I used Ruby 1.8 (very slow), would it make a difference compared to using Python 3.1 (Faster), or compiled C/C++?
If anyone can lend a hand and give some info or advice, I'd be eternally grateful.
I'll give this a shot:
In 2009, for a 50 player game, it doesn't matter. You may want to pick a language that you're familiar with profiling tools for, if you want to grow it further, but since RAM is so cheap nowadays, the constraints driving the early LPMUD (which I have experience with) and DikuMUD (which your Smaug is derived from) don't apply. (LPMUD could handle ~10-15 players on a machine with 8MB RAM)
The programming style doesn't necessarily lead to performance difficulties, large sites like Amazon's 'obidos' webserver are written in C, but just-as-large sites like the original Yahoo Stores were written in Lisp, StackOverflow is written in ASP.NET, etc. I'd /personally/ use C but many people would call me a sadist.
Flat Files are kind of pointless in today's day and age for lots of data storage, there are specific-case exceptions (Large mailservers sometimes use 'maildir' which is structured flat-files, for example). The size of your game likely means you won't be running into huge slowness driven by data retrieval delays, but the data integrity in-case-of-crash are probably going to make the most convincing argument.
Don't know of any guide, but what I'd do is try to get the game started as a dumb chat server to start, make sure users can log in and do something (take their input and dump it to all other users), then build that up to allowing specific logins, so you'll start facing the challenge of username/password handling, and user option setting / storage / retrieval ... then start adding the gamedriver elements (get tic tac toe games working in game), then go a little more complex (get a 5-room setup working with objects you can pick up / drop / bash each other with), then add some non-player characters, and THEN worry about slurping in the Diku-derived smaug castles / etc and working with them. :)
This is a bit off the cuff , I'm sure there are dissenting opinions. :) Good luck!
This is a text based game, right? In that case, with current hardware, it seems all you would have to worry about is not accidentally creating an O(n**2) algorithm. Even that probably wouldn't be too bad with 50 users.
I was using a CASE called MAGIC for a system I'm developing, I've never used this kind of tool before and at first sight I liked, a month later I had a lot of the application generated, I felt very productive and ... I would say ... satisfied.
In some way a felt uncomfortable, cause, there is no code and everything I was used to, but in the other hand I could speed up my developing. The fact is that eventually I returned to use C# because I find it more flexible to develop, I can make unit testing, use CVS, I have access to more resources and basically I had "all the control". I felt that this tool didn't give me confidence and I thought that later in the project I could not manage it due to its forced established rules of development. And also a lot of things like sending emails, using my own controls, and other things had their complication, it seemed that at some point it was not going to be as easy as initially I thought and as initially the product claims. This reminds me a very nice article called "No Silver Bullet".
This CASE had its advantages but on the other hand it doesn't have resources you can consult and actually the license and certification are very expensive. For me another dissapointing thing is that because of its simplistic approach for development I felt scared on first hand cause of my unexperience on these kind of tools and second cause I thought that if I continued using it maybe it would have turned to be a complex monster that I could not manage later in the project.
I think it's good to use these kind of solutions to speed up things but I wonder, why aren't these programs as popular as VS.Net, J2EE, Ruby, Python, etc. if they claim to enhance productivity better than the tools I've pointed?
We use a CASE tool at my current company for code generation and we are trying to move away from it.
The benefits that it brings - a graphical representation of the code making components 'easier' to pick up for new developers - are outweighed by the disadvantges in my opinion.
Those main disadvantages are:
We cannot do automatic merges, making it close to impossible for parallel development on one component.
Developers get dependant on the tool and 'forget' how to handcode.
Just a couple questions for you:
How much productivity do you gain compared to the control that you use?
How testable and reliant is the code you create?
How well can you implement a new pattern into your design?
I can't imagine that there is a CASE out there that I could write a test first and then use a CASE to generate the code I need. I'd rather stick to resharper which can easily do my mundane tasks and retain full control of my code.
The project I'm on originally went w/ the Oracle Development Suite to put together a web application.
Over time (5+ years), customer requirements became more complex than originally anticipated, and the screens were not easily maintainable. So, the team informally decided to start doing custom (hand coded) screens in web PL/SQL, instead of generating them using the Oracle Development Suite CASE tools (Oracle Designer).
The Oracle Report Builder component of the Development Suite is still being used by the team, as it seems to "get the job done" in a timely fashion. In general, the developers using the Report Builder tool are not very comfortable coding.
In this case, it seems that the productivity aspect of such CASE tools is heavily dependent on customer requirements and developer skill sets/training/background.
Unfortunaly the Magic tool doesn't generates code and also it can't implement a design pattern. I don't have control over the code cause as i stated before it doesn't have code to modify. Te bottom line is that it can speed up productivity in some way but it has the impossibility to user CVS, patterns also and I can't control all the details.
I agree with gary when he says "it seems that the productivity aspect of such CASE tools is heavily dependent on customer requirements and developer skill sets/training/background" but also I can't agree more with Klelky;
Those main disadvantages are:
1. We cannot do automatic merges, making it close to impossible for parallel development on one component.
2.Developers get dependant on the tool and 'forget' how to handcode.
Thanks