Raygui: An Immediate-Mode C UI for Wasm Tools Development

Welcome, everybody. My name is Roman Santamaria. I'm an electronic engineer, a professor, entrepreneur, and for the last few years I've been developing tools and technology for the video games industry.

Today I'm going to present one of those technologies that is RightGui, that is an immediate mode CUI library intended for tools development. Actually, this same presentation is a web application, as you can see. It's running on web. And the that's the tool. And the presentation itself has been created with RightGui to demonstrate the possibilities and the versatility of this tool.

Okay, so let's start. What can you do with RightGui? What is exactly RightGui? Well, RightGui actually is an immediate mode library. It means that it does not store information internally. It is stateless. So actually all the UI system is based on small functions that are self-contained that can not only process all the inputs, but also draw all the control in immediate mode. Here is an example. This piece of code in C actually defines a button at the same time that draws the button and receives back the state of the button. If the button has been pressed, it enables a variable that is on the user side. And if that variable is enabled, it actually shows another immediate mode UI control that is a message box with some information. You can see that that code generate the button and when you press the button, you see it generates a key message box. That's all the code needed for the button and the message box, including in itself all the logic. That's an immediate mode library.

Also, the library is really high performance. At the back end, it uses another of my technologies that is Riley, that it's a popular C library, a very high performance in itself. It's code in C. And that code is compiled through mscript to web assembly, allowing to run in a very performant web, in a very performant way, all that code on, on a web platform, on a browser. Also, thanks to being a C library, it is multi platform. As I said, you can see it can run on web, but, on a browser, but it can also run the same, exactly the same code can be compiled for Windows, Linux, MacOS, FreeBSD, and even embedded systems, Android, Raspberry Pi, more esoteric operating systems like haiku, or even other operating systems that are supported by, by Riley, by the backend. In that regards the library, RI-D, being animated mode library, has a very, very low memory footprint. Actually the library only requires about 145 kilobytes of memory, of RAM memory, that's the total requirement for the library, and that considers the styles provided. It's a global variable containing 348 properties for the styles that actually you can change. The icons, the library provides, as you can see here, those icons are provided by the library, there are up to 250 icons defined but you can add more if you want.

And also the font, the font actually is the most memory expensive element because it includes several fonts for multiple languages. But on all the styles defined, actually you can see here several styles that can be changing in real time. You see all those styles are up to 136 kilobytes including the font texture atlas and all the properties of the atlas for proper rendering of the font. So total memory for Footprint is 145 kilobytes.

Also the library includes a set of support tools that allows to edit styles as you have seen right now. There is a styles editor. All the styles you have seen have been created with that styles editor. The styles editor also runs online and it has been also created using ReiG. We will see more about that. There is also another tool that is an icons editor that has been used to create all the icons that you can see in the buttons and all around. And finally, there is a third tool that is a layout editor. I have to mention that ReiG has not an auto layout mechanism. It's only the layout must be defined by the user. So the user has full control over all the layout or how everything is placed around. We'll see a bit more about those tools later on.

And finally, everything you have seen, ReiLib, ReiG and all the tools that interact with ReiG and all the support tools, everything is free and open source. And you can find it here in this link. That's about the features. What about the controls? Okay, here you have a live example of some or most of the controls available in ReiG. You got labels. Actually those things are labels. You got drop-down buttons, checkboxes. You also have spinners. You got a text box. Actually, you can place the quotes or everything. You have got a text box. You got combo boxes, different states, a guillies view, a toggle groups. Also you've got a color picker selector with alpha bars and a few bars, a sliders, progress bar, scroll panels, grids. You even have a bit more rich text box. Those are the controls available.

Actually, an interesting point about the controls is that all the controls are just function calls. That's what immediate mode UI gives you. And all the controls have these functions, which define the rectangle of the control, the text contained in the control, and finally, some control state variable that should be returned to the user. For example, in the case of ListView, the selected item. The same goes for the toggle group. In the case of the panel, it returns the scroll bar position for scrolling. These are the variables returned. There are usually one or two variables for every control. And finally, we have a return variable that is some internal state for the control, returned as required as an integer. So, as you see, the usage of this immediate mode UI system is pretty simple. That's regarding the controls available. You can scale them, move them, and interact with them on the screen.

About the styles, I've already shown you what's available, but by default, I created a set of styles as a showcase, demonstrating how everything can be changed in the style. For example, there's a label with a specific size, a label with a specific color, and different styles with different fonts, font sizes, spacing, and line spacing for multiple lines. You can configure almost every style aspect you can imagine for the UI. These are some of the styles I created. Personally, I really like the pixel art UI style, retro UI style for my tools, and all the styles I created that follow those guidelines. But you can also load any standard form and customize the style to suit your needs.

Regarding the support tools, there are three support tools that allow you to configure any RightGui application developed for your needs. These tools are the Geo Styler, the Geo Icons, and the Geo Layout. They are all free and open source, and they are available online. You can find the tools on GitHub, and you can also use them online. One interesting point is that you can configure the style live in the tool and see the changes in real-time. For example, you can change the border color or the base color of the controls' text color.

The three tools are free and open source. Actually, they are available online. They are not only available on GitHub. Actually, here you can see the tool on GitHub, but also you got the tool published online that can be executed. And one interesting point is that you can configure the style live and in the same tool, you are seeing live how the tool style is changed. For example, if I change the border color, if I change the base color of the controls text color for example. Now, like that, you can change some specific control that affects all the controls but you can change some specific control. For example, the button, if I want the button a bit different now. I border color. I can change only the buttons now and well, you can change all the properties. You can also change the phone. Well, you have a full control, not only over all the controls as a default style, but also over every specific control, okay?

That's the gear styler but, oh yeah, you also have the icons editor. It's a simple icons editor. That's it so, here you can edit the icons. Those are the icons that are by default included in RaiGui. There are 256 slots for icons actually. At the moment there are still some slots not filled. Some contributors add new icons. Actually all those icons have been added by contributors lately and well at the moment there are 256 but yeah that can be incremented to whatever number.

Yeah and that's an icon editor you see. Yeah so and finally probably the most useful and the most interesting tool considering that Reigi has no automatic layout system. That the layout must be created by the user. It's a layout creator tool. For example we can place here controls We have actually it can be edited We can place textbox for example and make it bigger. You can create the layout and actually it's interesting that all the layouts are referenced by an anchor point and you can ask how if it's an immediate mode library that is actually only functions called how can I export that layout. Actually that's the interesting thing when you hit the export current layout. Actually it generates code, it generates automatically the C code for that layout. You can configure if it's C code, if it's containing a header only file, if you want to export anchors, rectangles, you have several configuration options to export the code in the way you want it to be added to your project. That's the layout actually. With that tool you can create auto contained layouts. For example, file browser, importer, exporter, window. You can create auto contained windows that can be exported as a self-contained file to be added to any project. That's one thing that I do with my projects. Beside the support Reiki tools we also have all those tools. Actually, as I said for the last few years I've been working not only on those technologies, Reiki and some other technologies, but I've also been for the last five years, I've been focused on tools development using my technologies. Here, there is a set of tools that I have created. Most of them are published and can be used online for free, and some are just internal. For me, for example, that's a tool to create tools in a visual way, etc. That's a text editor that has not been published yet. Some tools have not been... are not ready, but are not published, but most of them are published and actually can be used online.

Some of the tools created using Reiki are not ready, but are not published, but most of them are published and actually can be used online. For example, that's a sound editor that has been created also with Reiki. It's also free and open source, but then you have more complex tools like text tools. Actually, this tool is like a canvas to view images, apply shaders, apply transformations to the images and organize them in a kind of a board. Here you have some example images, because I got no images loaded, but you can see what can be done with that tool.

It runs online, but it's also available to download as a standalone tool. That's the multiplatform capabilities of Reiki. A texture packer, a stereography tool, a resource packer, for example. That tool is intended to package for video games, to package resources, images, text, shaders, models, audios, to pack tools into a self-contained package, with different compressions, encryptions, for every file. And you also have a installer creator, and et cetera. Actually, the set of tools available, it's quite wide. And actually, it proves that, well, those technologies work and they work on web, and they have been used in, in production for about five years now. And, yeah, that's it.

Okay. Wait, wait, wait, wait. Let's go full screen. And well, that would be my presentation of Rite Geek. I hope you enjoy it, you like it. And now if there is any question, feel free to ask. Thank you very much.