computing Computing is any goal-oriented activity requiring, benefiting from, or creating computer, computing machinery. It includes the study and experimentation of algorithmic processes, and the development of both computer hardware, hardware and softw ...

, Nano-X is a windowing system which is full featured enough to be used on a PC, an

embedded system An embedded system is a specialized computer system—a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function within a larger mechanical or electronic system. It is e ...

or a PDA. It is an

open source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use and view the source code, design documents, or content of the product. The open source model is a decentrali ...

project aimed at bringing the features of modern graphical windowing environments to smaller devices and platforms. The project was renamed from Microwindows due to legal threats from Microsoft regarding the

Windows Windows is a Product lining, product line of Proprietary software, proprietary graphical user interface, graphical operating systems developed and marketed by Microsoft. It is grouped into families and subfamilies that cater to particular sec ...

trademark.

Overview

The Nano-X Window System is extremely portable, and completely written in C. It has been ported to the Intel 16, 32 and 64 bit CPUs, the

Broadcom Broadcom Inc. is an American multinational corporation, multinational designer, developer, manufacturer, and global supplier of a wide range of semiconductor and infrastructure software products. Broadcom's product offerings serve the data cen ...

BCM2837

ARM Cortex-A53 The ARM Cortex-A53 is one of the first two central processing units implementing the ARMv8-A 64-bit instruction set designed by ARM Holdings' Cambridge design centre, along with the Cortex-A57. The Cortex-A53 is a 2-wide decode superscalar p ...

, as well as MIPS R4000 (NEC Vr41xx)

StrongARM The StrongARM is a family of computer microprocessors developed by Digital Equipment Corporation and manufactured in the late 1990s which implemented the ARM v4 instruction set architecture. It was later acquired by Intel in 1997 from DEC's o ...

and

PowerPC PowerPC (with the backronym Performance Optimization With Enhanced RISC – Performance Computing, sometimes abbreviated as PPC) is a reduced instruction set computer (RISC) instruction set architecture (ISA) created by the 1991 Apple Inc., App ...

chips found on handheld and pocket PCs. The Nano-X Window System currently runs on

Linux Linux ( ) is a family of open source Unix-like operating systems based on the Linux kernel, an kernel (operating system), operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically package manager, pac ...

systems with kernel framebuffer support, or using an

X11 The X Window System (X11, or simply X) is a windowing system for bitmap displays, common on Unix-like operating systems. X originated as part of Project Athena at Massachusetts Institute of Technology (MIT) in 1984. The X protocol has been at ...

driver that allows Microwindows applications to be run on top of the X Window desktop. This driver emulates all of Microwindows' truecolor and palette modes so that an application can be previewed using the target system's display characteristics directly on the desktop display, regardless of the desktop display characteristics. In addition, it has been ported to

Emscripten Emscripten is an LLVM/Clang-based compiler that compiles C and C++ source code to WebAssembly, primarily for execution in web browsers. Emscripten allows applications and libraries written in C or C++ to be compiled ahead of time and run effi ...

, Android (based on the

Allegro Allegro may refer to: Common meanings * Allegro (music), a tempo marking that indicates to playing quickly and brightly (from Italian meaning ''cheerful'') * Allegro (ballet), brisk and lively movement Artistic works * L'Allegro (1645), a poem b ...

library), and

MS-DOS MS-DOS ( ; acronym for Microsoft Disk Operating System, also known as Microsoft DOS) is an operating system for x86-based personal computers mostly developed by Microsoft. Collectively, MS-DOS, its rebranding as IBM PC DOS, and a few op ...

. Microwindows screen drivers have been written based on the SDL1 and SDL2 libraries plus the

and SVGAlib libraries. There are also a

VESA VESA (), formally known as Video Electronics Standards Association, is an American standards organization, technical standards organization for computer display standards. The organization was incorporated in California in July 1989To retrieve ...

and a

VGA Video Graphics Array (VGA) is a video display controller and accompanying de facto graphics standard, first introduced with the IBM PS/2 line of computers in 1987, which became ubiquitous in the IBM PC compatible industry within three years. T ...

16 color 4 planes driver.

Architecture

Layered design

Microwindows is essentially a layered design that allows different layers to be used or rewritten to suit the needs of the implementation. At the lowest level,

screen Screen or Screens may refer to: Arts * Screen printing or ''silkscreening'', a printing method * Big screen, a nickname for motion pictures * Split screen (filmmaking), showing two or more images side by side * Stochastic screening and Halftone ...

mouse A mouse (: mice) is a small rodent. Characteristically, mice are known to have a pointed snout, small rounded ears, a body-length scaly tail, and a high breeding rate. The best known mouse species is the common house mouse (''Mus musculus'' ...

touchpad A touchpad or trackpad is a type of pointing device. Its largest component is a tactile sensor: an electronic device with a flat surface, that detects the motion and position of a user's fingers, and translates them to 2D motion, to control a Cu ...

and

keyboard Keyboard may refer to: Text input * Keyboard, part of a typewriter * Computer keyboard ** Keyboard layout, the software control of computer keyboards and their mapping ** Keyboard technology, computer keyboard hardware and firmware Music * Mus ...

drivers provide access to the actual display and other user-input hardware. At the mid level, a portable graphics engine is implemented, providing support for line draws, area fills, polygons, clipping and color models. At the upper level, three API's are implemented providing access to the graphics applications programmer. Currently, Microwindows supports the Xlib, Nano-X and Windows

Win32 The Windows API, informally WinAPI, is the foundational application programming interface (API) that allows a computer program to access the features of the Microsoft Windows operating system in which the program is running. Programs can acces ...

WinCE Windows CE, later known as Windows Embedded CE and Windows Embedded Compact, is a discontinued operating system developed by Microsoft for mobile and embedded devices. It was part of the Windows Embedded family and served as the software found ...

GDI GDI may refer to: Science and technology * Gasoline direct injection, a type of fuel injection * Graphics Device Interface, a component of Microsoft Windows * Guanosine nucleotide dissociation inhibitor, a protein Organisations * Gabriel Dumont I ...

APIs. These APIs provide close compatibility with the Win32 and

X Window The X Window System (X11, or simply X) is a windowing system for bitmap displays, common on Unix-like operating systems. X originated as part of Project Athena at Massachusetts Institute of Technology (MIT) in 1984. The X protocol has been a ...

systems, however, with reduced functionality. These APIs allow programs to be ported from other systems easily.

Device drivers

The device driver interfaces are defined in device.h. A given implementation of Microwindows will link at least one screen, mouse and keyboard driver into the system. The mid level routines in the device-independent graphics engine core then call the device driver directly to perform the hardware-specific operations. This setup allows varying hardware devices to be added to the Microwindows system without affecting the way the entire system works.

Application programmer interfaces

Microwindows currently supports three different

application programming interface An application programming interface (API) is a connection between computers or between computer programs. It is a type of software Interface (computing), interface, offering a service to other pieces of software. A document or standard that des ...

s (APIs). This set of routines handles

client Client(s) or The Client may refer to: * Client (business) * Client (computing), hardware or software that accesses a remote service on another computer * Customer or client, a recipient of goods or services in return for monetary or other valuable ...

–

server Server may refer to: Computing *Server (computing), a computer program or a device that provides requested information for other programs or devices, called clients. Role * Waiting staff, those who work at a restaurant or a bar attending custome ...

activity,

window manager A window manager is system software that controls the placement and appearance of window (computing), windows within a windowing system in a graphical user interface. Most window managers are designed to help provide a desktop environment. They ...

activities like drawing title bars, close boxes, etc., as well as handling the programmer's requests for graphics output. These APIs run on top of the core graphics engine routines and device drivers.

NX11 API

The NX11 API is compliant with the

API. It is based on the Nano-X API and provides Xlib functions using the functions available in the Nano-X API. It can be compiled as a separate library or together with Nano-X library as a single library called libPX11. In all it provides 180 Xlib functions and stubs for additional functions not implemented. Based on the NX11 API the

FLTK Fast Light Toolkit (FLTK) is a cross-platform widget (graphical control element) library for graphical user interfaces (GUIs), developed by Bill Spitzak and others. Made to accommodate 3D graphics programming, it has an interface to OpenGL, but ...

graphical user interface A graphical user interface, or GUI, is a form of user interface that allows user (computing), users to human–computer interaction, interact with electronic devices through Graphics, graphical icon (computing), icons and visual indicators such ...

library can be used to provide a

GUI Gui or GUI may refer to: People Surname * Gui (surname), an ancient Chinese surname, ''xing'' * Bernard Gui (1261 or 1262–1331), inquisitor of the Dominican Order * Luigi Gui (1914–2010), Italian politician * Gui Minhai (born 1964), Ch ...

for application programs. The

Nanolinux NanoLinux is an open source, free and very lightweight Linux distribution that requires only 14 MB of disk space including tiny versions of the most common desktop applications and several games. It is based on the Core version of the Tiny Core ...

distribution uses the NX11 API and FLTK to implement a Linux operating system using 19 MB of disk space.

Nano-X API

The Nano-X API is modeled after the mini-x server written initially by David Bell, which was a reimplementation of X on the

MINIX MINIX is a Unix-like operating system based on a microkernel Software architecture, architecture, first released in 1987 and written by American-Dutch computer scientist Andrew S. Tanenbaum. It was designed as a clone of the Unix operating syste ...

operating system. It loosely follows the X Window System Xlib API, but the names all being with GrXXX() rather than X...(). The basic model of any API on top of Microwindows is to initialize the screen, keyboard and mouse drivers, then hang in a select() loop waiting for an event. When an event occurs, if it is a system event like keyboard or mouse activity, then this information is passed to the user program converted to an expose event, paint message, etc. If it is a user requesting a graphics operation, then the parameters are decoded and passed to the appropriate GdXXX engine routine. Note that the concept of a window versus raw graphics operations is handled at this API level. That is, the API defines the concepts of what a window is, what the coordinate systems are, etc., and then the coordinates are all converted to "screen coordinates" and passed to the core GdXXX engine routines to do the real work. This level also defines graphics or display contexts and passes that information, including clipping information, to the core engine routines.

Microwindows API

The API which tries to be compliant with the Microsoft Win32 and WinCE GDI standard is the Microwindows API.Linux + Microwindows: challenger to WinCE
/ref> Currently, there is support for most of the graphics drawing and clipping routines, as well as automatic window title bar drawing and dragging windows for movement. The Microwindows API is message-based, and allows programs to be written without regard to the eventual window management policies implemented by the system. The Microwindows API is not currently client/server. The fundamental communications mechanism in the Microwindows API is the message. A message consists of a well-known message number, and two parameters, known as wParam and lParam. Messages are stored in an application's message-queue, and retrieved via the GetMessage function. The application blocks while waiting for a message. There are messages that correspond to hardware events, like WM_CHAR for keyboard input or WM_LBUTTONDOWN for mouse button down. In addition, events signaling window creation and destruction WM_CREATE and WM_DESTROY are sent. In most cases, a message is associated with a window, identified as an HWND. After retrieving the message, the application sends the message to the associated window's handling procedure using DispatchMessage. When a window class is created, its associated message handling procedure is specified, so the system knows where to send the message. The message-passing architecture allows the core API to manage many system functions by sending messages on all sorts of events, like window creation, painting needed, moving, etc. By default, the associated window handling function gets a "first pass" at the message, and then calls the DefWindowProc function, which handles default actions for all the messages. In this way, all windows can behave the same way when dragged, etc., unless specifically overridden by the user. Major window management policies can be redefined by merely re-implementing DefWindowProc, rather than making changes throughout the system. The basic unit of screen organization in Microwindows API is the window. Windows describe an area of the screen to draw onto, as well as an associate "window procedure" for handling messages destined for this window. Applications programmers can create windows from pre-defined classes, like buttons, edit boxes, and the like, or define their own window classes. In both cases, the method of creating and communicating with the windows remains exactly the same.

History

Nano-X's origin is with NanoGUI. NanoGUI was created by Alex Holden by taking David Bell's mini-X server and Alan Cox's modifications and adding client/server networking. Gregory Haerr then took interest in the NanoGUI project and began making extensive enhancements and modifications to NanoGUI. Around version 0.5, Gregory Haerr added support for multiple API's, and began distributing Microwindows. In Microwindows 0.84, all previous NanoGUI changes were incorporated and since then has been the combined NanoGUI/Microwindows distribution. In January 2005, the system changed its name to the Nano-X Window System. Because Nano-X just loosely follows the X Window System Xlib API, an additional interface was developed named NXlib, which provides an Xlib compatible API based on Nano-X.

References

{{reflist

External links

Microwindows on GitHub for the latest versionMicrowindows.org websiteIntroduction to Microwindows ProgrammingIntroduction to Microwindows Programming, Part 2Introduction to Microwindows Programming, Part 3
Application programming interfaces X Window System C (programming language) libraries Programming tools