creating gui overlay interface in game - user-interface

I've created a relatively simple tower defense game using c++ and SFML. I'm very interested in creating a nice gui overlay for it, ie hud, menus, etc. I know there are a lot of gui libraries out there, but I would like to make my own (for learning purposes.
I'm very familiar with working with graphics, but I'm not as familiar with GUI systems (I just render my frames, and don't worry about widgets, title bars, etc.).
Are there any good articles out there, or perhaps suggestions anyone has regarding how to layout such an interface?

There are a couple ways I know of (at least for Java) to get a nice HUD in your game. One method is to have a separate 3D world with the UI elements placed directly in front of the camera, then overlay that camera's view over the main view. This can be buggy at times, especially when you don't have a good color filter, or when you have a high number of objects being displayed. Another method is to look at a GUI library designed for this purpose (such as NiftyGUI for Java).
A quick Google search lead me to a listing on Wikipedia of many open-source GUI libraries you could use. There are many others out there, so you should probably do the Google search yourself, or look around on GitHub and SourceForge.

Related

2D graphics without OpenGL / DirectX as for a GUI Toolkit

I am wondering how to create some 2D graphics without using OpenGL or DirectX. Like, what do e.g. Qt or GTK use, to draw what is basically colored rectangles (and text)?
I know that with KDE 5 and Gnome 3 there were some complains that now OpenGL is required (for certain effects including 3D stuff like the desktop cube that was trendy for a while). So apparently something simpler was used before, yet I can't find out what. Here the answers are basically: OpenGL or SDL …
Well the most basic way you have to draw a window on linux is to use Xlib or Win32 on windows. These are very basic window drawing APIs that also handle events. But it would probably be a lot of work to use them on their own.
SDL, SFML, or OpenGL are probably better options in most cases, since window rendering protocols can draw rectangles and images but lack a lot of QoL features that make your life as a dev easier. Maybe if you are looking for the absolute best performance Xlib (or wayland) would be the way to go, but if you are looking for a simple way to code a GUI application it's probably a bad idea.
If you want a great and easy to use GuI to do menus and stuffs, dear ImGui is very impressive and easy to use, and can run in a variety of rendering surfaces including SDL and DirectX
Also this answer could help you, it's seems a bit close :
Does OpenGL use Xlib to draw windows and render things, or is it the other way around?
You'll notice that at the end they talk of other ways to draw windows which are AGG and Cairo. It's a bit of a wall text but a greatly detailed answer.

Best low level canvas library for making interactive animations?

I'm evaluating canvas libraries, and my needs are:
I want to make it easy to build nice looking buttons that move
around and on which I can easily capture events. Button drawing
helpers would be cool
I'll be building a system for others to use to create animated
scenes combining moving test, images, and sound. I won't ever be
drawing complex shapes myself, the most I might be drawing is
buttons around some text.
I do not want to be totally insulated from the low level machinery
of the per-frame drawing callback. Helped along sure, but
I'm going to be syncing with Web Audio API stuff and want to keep
access to super tight timing control
I'm comfortable with pretty low level scripting of animation, would rather not have it be something that changes Canvas into some
totally different paradigm, but not sure on this point
needs to work well for touch on iOs
I'd ideally like to be using one with good docs and a high truck number. The state of Canvas libs reminds me of the state of JS libs
10 years ago, and I'd rather not invest in something that doesn't
have an actual "team" behind it. Truck number == 1 worries me.
You flagged KineticJS, so I can say a little bit about how that would work.
1) It's a great tool for tracking shapes on a canvas, capturing clicks, and moving them around. It's easy to place an image on any shape, but I would use another program to make those images.
2) Even if you don't do a lot beyond buttons, KineticJS provides some nice features for manipulating the canvas, and I'm sure you'd use a lot of them in making tools for others.
3) KineticJS provides an animation object that repeatedly calls the draw() method for you. You define your draw method in order to create animations.
4) It's more of a wrapper around canvas. You work with a Stage and Layers, but there is still a lot of transparency to the canvas itself, and you can always do direct manipulation as well.
5) You can capture a broad range of events including "touch", "click", etc. It's easy to treat them the same when appropriate or differently if you need to. Furthermore, you can simply mark shapes as "draggable" and it handles all that appropriately.
6) Kinetic has had spectacular documentation and examples, but in looking now, the tutorials seem to be missing from http://kineticjs.com/ and I can't find them elsewhere. That's minorly worrisome, but the docs are still there and my guess is that they'll be back up soon since KineticJS is still under active development.
I'll weigh in on #1:
Nice looking buttons:
Hands-down...use Adobe Illustrator to create a set of button vector images (.svg).
If you need low level control over the button design at run-time then convert the Illustrator images to canvas drawing commands with this great plugin from Mike Swanson:
http://blog.mikeswanson.com/post/29634279264/ai2canvas.
The key here is that canvas will scale the vector button for you so you're always getting a professional, polished look both on a small mobile screen and a large desktop screen.
You could use canvas to build each part of a button from scratch, but don't reinvent the wheel.
A good animation library is Greensock. It also helps you build timelines (kind of like Flash timelines).
http://www.greensock.com/gsap-js/
As to canvas libraries, check out Stackoverflow's sister site that offers software recommendations:
http://softwarerecs.stackexchange.com
Good luck with your project!

How are GUI's really made?

My question is
Gui libraries like Qt and lets say for Windows operating systems
how do they create all those graphical user interfaces(windows etc).
Does each operating system gives API's or something else to do so?If yes, then how operating systems draw all those windows and things.Do they (operating systems) "control" the screen and then draw each pixel one by one to achieve their goal the GUI?
I would like an answer that explains things at the lowest level possible but well i don't demand someone to write me everything that happens( even if i would like to) because i know many things are behind all these.So for this reason comments with links or suggested books which explain with details
on what is happening under the hood would be appreciated.
Stackoverflow answers are not supposed to use links, comments can but not answers.
Each operating system and gui library is different, but, yes in some way, shape, or form they do actually draw every one of the pixels. It is often quite organized and many peformance solutions are used, optimized routines that can update a rectangle or some chunk of a screen, sometimes hardware gets involved (these days a lot of the time the hardware or basically gpus get involved the cpu asks the gpu to draw something then the gpus are busy placing all the pixels).
You would likely for example want to create some sort of font rendering function that is given the font, the string to display, the font size, and perhaps a clipping window to not go outside, or perhaps a function that with the font, size and string returns the number of pixels then you can adjust the string to fit and wrap (look around this web page for example, drag the window wider and narrower and watch what web text does).
Definitely some sort of image drawing routines with the ability to stretch or fit the drawing to the rectangle defined.
The fun stuff, games, etc has improved so rapidly over time that it is hard to go back to a simple line draw and area fill routine, etc. But also along with the technology the games brought simple things like web pages benefit...Again look around.
There are many open source programs and libraries you should just wander around the source code and see what you see.
The operating system provides libraries that interface with the monitor/display. In short, GUI libraries such as Qt interact with those libraries of the operating system and creates an easier bridge for you, the programmer to interact with the monitor. For instance, Qt might have a drawLine feature, which underneath is taking care of pixel arrangement related to drawing on the monitor/display for the operating system.

How do I do simple 3D in XNA on Windows Phone 7

I'm a newbie to 3D on WP7. All I want to do is nice simple 3D
A. Add/Draw a number of coloured primitives, cube and spheres etc. to a 3D world
B. Rotate the World x, y and/or z
That's it, nothing else. I don't need any collision detection, I don't need any clever physics I don't need any textures or backgrounds or anything else, just that nice and simple.
I've been through about a gazillion examples on various websites and they all obscure the basics with bloated code and objects that I just don't want. I don't want any marble or spaceship examples, just some nice clean, clear code.
I have Blender to create the 3D models and these will be simple models with no textures. just solid basic 3D objects.
Please don't point me to anything that's based on a game which every example I have already found is.
Oh and please only examples that actually work.
Well the best way to do 3D on Windows Phone 7 is to use XNA which is generally associated with games which isn't the whole truth. You can still build traditional applications using XNA, although it might take you longer to construct your ui as opposed to silverlight.
You should probably check out App Hub from Microsoft as there are a ton of samples, in fact they have a category specifically for 3D. Keep in mind since your just starting you should make an attempt to understand the examples there giving you. Even though code you see for the first time might seem like bloated or extra code, there actually necessary components to consider when developing 3D applications.
At any rate, this example goes over the basics of 3D using XNA on Windows Phone 7.
EDIT: If you don't want to use XNA, there's this question that was asked previously. There's a couple of solutions for using 3D in silverlight.

Should I use HTML5 Canvas or CSS3 Sprites to animate objects for a game?

I'm in the process of starting to build a strategy game (think warcraft) for the web. I've been doing research on HTML5 Canvas and CSS3 sprites and still can't decide which technology to use.
The game won't be completed for another 6 months.
Any advice would be appreciated.
As you probably hear so frequently... "It Depends..." ™
My suggestion would be consider the feel of the application you're after. If you are trying to build a very graphically rich, mostly-images application, then I would use Canvas. However if you are trying to animate some graphics, but have the page remain and behave more "Web-like", mixed with other HTML content, I'd give CSS3 a try.
Two additional points:
Currently, Canvas is better supported than CSS3 animation/sprites.
If you use Canvas you're going to be implementing your own render loop and animation code (or making use of a 3rd partly library). Your code create animation by compositing the various layers of each frame, applying movement, and repeating. You can't simply say "move this image a little to the right". You'll have to do that yourself.
The EA web game "Lords of Ultima", as dull as it is, is an excellent example of a WarCraft-styled (well, it's more city building as there are no visible units) overworld, with animations and everything, built on a pure HTML and CSS sprite base. It looks and performs well and I think the square block box-model nature of HTML suits that kind of tile based design, especially since a lot of the image processing (embed an <img> or a <div> with a background, change background-position for animation) and click/mouse handling is done for you in simple html.
If you do go canvas you have to manage that yourself which will greatly increase the complexity and dev time. You'll have more control of minor elements and improved performance, but then you'll also lose (if it's at all important), greater backwards compatibility with older browsers. So it depends on how complex your design is and what kind of performance you need.
Use Canvas. If you use CSS sprites to build a game, then you are going to make a lots of <div>'s which performs operations on the DOM, which may slow down and also have a lots of focus and compatibility problems.
It may pay off to trade the development time for performance on <canvas>, by the assumption of "A code will be maintained forever".
I think CSS3 sprite system takes more time to develop, because you need to handle browser compatibility.
Browsers like IE 8 (8 or 9?) are using GPU to accelerate graphics, which lets you get the free lunch of Moore's Law.
There's pros and cons to both. Currently, Canvas is better supported then is CSS3, but you said that your game won't be done for another 6 months, by then the support for CSS3 could be much much better. There's also a lot of other variables here, such as: What browser will the game be viewed on? How advanced are the graphics you need to animate? etc... I would say that canvas would be better for support of the current generation of browsers and for gaming graphics, however CSS3 would be quicker, but wouldn't even come close to the support or graphics handling. But it doesn't seem like your in a rush to get it done.
Basically:
Canvas: Graphics, current support in users browser
CSS3: Speed of development
Ether will work. But for now I would use Canvas. However, 6 months in the tech world is an eternity, things could be a lot different then.

Resources