glfw/README.md
Camilla Berglund 6fadf37bda Replaced window close parameter with mutable flag.
Replaced the GLFW_SHOULD_CLOSE window parameter with the
glfwWindowShouldClose and glfwSetWindowShouldClose functions, allowing
the setting of the close flag from any point in the program.
2013-03-01 14:13:45 +01:00

20 KiB

GLFW 3.0

Introduction

GLFW is a free, Open Source, portable library for OpenGL and OpenGL ES application development. It provides a simple, platform-independent API for creating windows and contexts, reading input, handling events, etc.

Version 3.0 brings a new API with many new features such as multiple windows and contexts, multi-monitor support, EGL and OpenGL ES support, clipboard text support, an error description callback, gamma ramp control, layout-independent keyboard input and UTF-8 for all strings.

Certain features like the threading and image loading functions from GLFW 2.x have been removed.

Compiling GLFW

To compile GLFW and the accompanying example programs, you will need the CMake build system.

CMake options

There are a number of CMake build options for GLFW, although not all are available on all supported platforms. Some of these are de facto standards among CMake users and so have no GLFW_ prefix.

Shared options

BUILD_SHARED_LIBS determines whether GLFW is built as a static library or as a DLL / shared library / dynamic library.

LIB_SUFFIX affects where the GLFW shared /dynamic library is installed. If it is empty, it is installed to $PREFIX/lib. If it is set to 64, it is installed to $PREFIX/lib64.

GLFW_BUILD_EXAMPLES determines whether the GLFW examples are built along with the library.

GLFW_BUILD_TESTS determines whether the GLFW test programs are built along with the library.

Mac OS X specific options

GLFW_USE_CHDIR determines whether glfwInit changes the current directory of bundled applications to the Contents/Resources directory.

GLFW_USE_MENUBAR determines whether the first call to glfwCreateWindow sets up a minimal menu bar.

GLFW_BUILD_UNIVERSAL determines whether to build Universal Binaries.

Windows specific options

USE_MSVC_RUNTIME_LIBRARY_DLL determines whether to use the DLL version of the Visual C++ runtime library.

EGL specific options

GLFW_USE_EGL determines whether to use EGL instead of the platform-specific context creation API. Note that EGL is not yet provided on all supported platforms.

GLFW_CLIENT_LIBRARY determines which client API library to use. If set to opengl the OpenGL library is used, if set to glesv1 for the OpenGL ES 1.x library is used, or if set to glesv2 the OpenGL ES 2.0 library is used. The selected library and its header files must be present on the system for this to work.

Installing GLFW

A rudimentary installation target is provided for all supported platforms via CMake.

Using GLFW

There are two aspects to using GLFW:

  • Using the GLFW API
  • Compiling and linking programs using the GLFW library

The first point is covered in the WIP reference manual.

Include the GLFW header file

In the files of your program where you use OpenGL or GLFW, you should include the GLFW 3 header file, i.e.:

#include <GL/glfw3.h>

This defines all the constants, types and function prototypes of the GLFW API. It also includes the chosen client API header files (by default OpenGL), and defines all the constants and types necessary for those headers to work on that platform.

For example, under Windows you are normally required to include windows.h before including GL/gl.h. This would make your source file tied to Windows and pollute your code's namespace with the whole Win32 API.

Instead, the GLFW header takes care of this for you, not by including windows.h, but rather by itself duplicating only the necessary parts of it. It does this only where needed, so if windows.h is included, the GLFW header does not try to redefine those symbols.

In other words:

  • Do not include the OpenGL headers yourself, as GLFW does this for you
  • Do not include windows.h or other platform-specific headers unless you plan on using those APIs directly
  • If you do need to include such headers, do it before including the GLFW and it will detect this

If you are using an OpenGL extension loading library such as GLEW, the GLEW header should also be included before the GLFW one. The GLEW header defines macros that disable any OpenGL header that the GLFW header includes and GLEW will work as expected.

GLFW header option macros

These macros may be defined before the inclusion of the GLFW header.

GLFW_INCLUDE_GLCOREARB makes the header include the modern GL/glcorearb.h header (OpenGL/gl3.h on Mac OS X) instead of the regular OpenGL header.

GLFW_INCLUDE_ES1 makes the header include the OpenGL ES 1.x GLES/gl.h header instead of the regular OpenGL header.

GLFW_INCLUDE_ES2 makes the header include the OpenGL ES 2.0 GLES2/gl2.h header instead of the regular OpenGL header.

GLFW_INCLUDE_ES3 makes the header include the OpenGL ES 3.0 GLES3/gl3.h header instead of the regular OpenGL header.

GLFW_INCLUDE_GLU makes the header include the GLU header. This only makes sense if you are using OpenGL.

GLFW_DLL is necessary when using the GLFW DLL on Windows.

Using GLFW from CMake

The GLFW_LIBRARIES cache variable contains all link-time dependencies of GLFW as it is currently configured, so to link against GLFW simply do:

target_link_libraries(myapp glfw ${GLFW_LIBRARIES})

Note that this does not include GLU, as GLFW does not use it. If your application needs GLU, you can add it to the list of dependencies with the OPENGL_glu_LIBRARY cache variable.

Windows static library

The static version of the GLFW library is named glfw3. When using this version, it is also necessary to link with some libraries that GLFW uses.

When linking a program under Windows that uses the static version of GLFW, you must link with opengl32. If you are using GLU, you must also link with glu32.

Windows DLL

The link library for the GLFW DLL is named glfw3dll. When compiling a program that uses the DLL version of GLFW, you need to define the GLFW_DLL macro before any inclusion of the GLFW header. This can be done either with a compiler switch or by defining it in your source code.

A program using the GLFW DLL does not need to link against any of its dependencies, but you still have to link against opengl32 if your program uses OpenGL and glu32 if it uses GLU.

Unix library

GLFW supports pkg-config, and glfw3.pc file is generated when the library is built and installed along with it. You can use it without installation using the PKG_CONFIG_PATH environment variable. See the documentation for pkg-config for more details.

A typical compile and link command-line when using the static may look like this:

cc `pkg-config --cflags glfw3` -o myprog myprog.c `pkg-config --static --libs glfw3`

If you are using the shared library, simply omit the --static flag.

If you are using GLU, you should also add -lGLU to your link flags.

Mac OS X static library

GLFW on Mac OS X uses the Cocoa, OpenGL and IOKit frameworks.

If you are using Xcode, you can simply add the GLFW library and these frameworks as dependencies.

If you are building from the command-line, it is recommended that you use pkg-config

GLFW supports pkg-config, and glfw3.pc file is generated when the library is built and installed along with it. You can use it without installation using the PKG_CONFIG_PATH environment variable. See the documentation for pkg-config for more details.

You can find pkg-config in most package systems such as Fink and MacPorts, so if you have one of them installed, simply install pkg-config. Once you have pkg-config available, the command-line for compiling and linking your program is:

cc `pkg-config --cflags glfw3` -o myprog myprog.c `pkg-config --static --libs glfw3`

If you do not wish to use pkg-config, you need to add the required frameworks and libraries to your command-line using the -l and -framework switches, i.e.:

cc -o myprog myprog.c -lglfw -framework Cocoa -framework OpenGL -framework IOKit

Note that you do not add the .framework extension to a framework when adding it from the command-line.

The OpenGL framework contains both the OpenGL and GLU APIs, so there is no need to add additional libraries or frameworks when using GLU. Also note that even though your machine may have libGL-style OpenGL libraries, they are for use with the X Window System and will not work with the Mac OS X native version of GLFW.

Changes for version 3.0

  • Added GLFWmonitor and updated monitor-related functions to take a monitor handle
  • Added glfwGetMonitors and glfwGetPrimaryMonitor for enumerating available monitors
  • Added glfwGetMonitorPos, glfwGetMonitorPhysicalSize and glfwGetMonitorName for retrieving monitor properties
  • Added glfwSetMonitorCallback and GLFWmonitorfun for notification of changes in the set of available monitors
  • Added GLFWwindow and updated window-related functions and callbacks to take a window handle
  • Added glfwSetWindowShouldClose and glfwWindowShouldClose for setting and retrieving the window close flag
  • Added glfwGetWindowPos for retrieving the position of a window
  • Added glfwDefaultWindowHints for resetting all window hints to their default values
  • Added glfwMakeContextCurrent for making the context of the specified window current
  • Added glfwSetErrorCallback, GLFWerrorfun and error type tokens for receiving error notifications
  • Added glfwSetWindowUserPointer and glfwGetWindowUserPointer for per-window user pointers
  • Added glfwGetVersionString for determining which code paths were enabled at compile time
  • Added glfwGetWindowMonitor for querying the monitor, if any, of the specified window
  • Added glfwSetWindowPosCallback and GLFWwindowposfun for receiving window position events
  • Added glfwSetWindowFocusCallback and GLFWwindowfocusfun for receiving window focus events
  • Added glfwSetWindowIconifyCallback and GLFWwindowiconifyfun for receiving window iconification events
  • Added glfwGetClipboardString and glfwSetClipboardString for interacting with the system clipboard
  • Added glfwGetJoystickName for retrieving the name of a joystick
  • Added glfwGetCurrentContext for retrieving the window whose OpenGL context is current
  • Added GLFW_SRGB_CAPABLE for requesting sRGB capable framebuffers
  • Added GLFW_CLIENT_API and its values GLFW_OPENGL_API and GLFW_OPENGL_ES_API for selecting client API
  • Added GLFW_CONTEXT_ROBUSTNESS and values GLFW_NO_ROBUSTNESS, GLFW_NO_RESET_NOTIFICATION and GLFW_LOSE_CONTEXT_ON_RESET for GL_ARB_robustness support
  • Added GLFW_OPENGL_REVISION to make up for removal of glfwGetGLVersion
  • Added GLFW_INCLUDE_GLCOREARB macro for including GL/glcorearb.h instead of GL/gl.h
  • Added GLFW_INCLUDE_ES1 macro for telling the GLFW header to use GLES/gl.h instead of GL/gl.h
  • Added GLFW_INCLUDE_ES2 macro for telling the GLFW header to use GLES2/gl2.h instead of GL/gl.h
  • Added GLFW_VISIBLE window hint and parameter for controlling and polling window visibility
  • Added GLFW_REPEAT key action for repeated keys
  • Added windows simple multi-window test program
  • Added sharing simple OpenGL object sharing test program
  • Added modes video mode enumeration and setting test program
  • Added threads simple multi-threaded rendering test program
  • Added glfw3native.h header and platform-specific functions for explicit access to native display, window and context handles
  • Added glfwSetGamma, glfwSetGammaRamp and glfwGetGammaRamp functions and GLFWgammaramp type for monitor gamma ramp control
  • Added window parameter to glfwSwapBuffers
  • Changed buffer bit depth parameters of glfwOpenWindow to window hints
  • Changed glfwOpenWindow and glfwSetWindowTitle to use UTF-8 encoded strings
  • Changed glfwGetProcAddress to return a (generic) function pointer
  • Changed glfwGetVideoModes to return a dynamic, unlimited number of video modes for the specified monitor
  • Renamed glfw.h to glfw3.h to avoid conflicts with 2.x series
  • Renamed glfwOpenWindowHint to glfwWindowHint
  • Renamed GLFW_ACTIVE to GLFW_FOCUSED
  • Renamed GLFW_FSAA_SAMPLES to GLFW_SAMPLES
  • Renamed GLFW_WINDOW_NO_RESIZE to GLFW_RESIZABLE
  • Renamed GLFW_BUILD_DLL to _GLFW_BUILD_DLL
  • Renamed version test to glfwinfo
  • Renamed GLFW_NO_GLU to GLFW_INCLUDE_GLU and made it disabled by default
  • Renamed glfwGetJoystickPos to glfwGetJoystickAxes to match glfwGetJoystickButtons
  • Renamed mouse position functions to cursor position equivalents
  • Replaced glfwOpenWindow and glfwCloseWindow with glfwCreateWindow and glfwDestroyWindow
  • Replaced glfwGetDesktopMode width glfwGetVideoMode
  • Replaced ad hoc build system with CMake
  • Replaced layout-dependent key codes with single, platform-independent set based on US layout
  • Replaced mouse wheel interface with two-dimensional, floating point scrolling interface
  • Replaced glfwEnable and glfwDisable with glfwGetInputMode and glfwSetInputMode
  • Replaced joystick test with graphical version
  • Replaced automatic closing of windows with the window close flag
  • Removed the GLFW_KEY_REPEAT input option
  • Removed event auto-polling and the GLFW_AUTO_POLL_EVENTS window enable
  • Removed the Win32 port .def files
  • Removed the entire threading API
  • Removed the entire image loading API
  • Removed deprecated Carbon port
  • Removed registering glfwTerminate with atexit
  • Removed glfwSleep function
  • Removed glfwGetNumberOfProcessors function
  • Removed glfwGetGLVersion function
  • Removed GLFW_OPENED window parameter
  • Removed GLFW_WINDOW and GLFW_FULLSCREEN
  • Removed nonsensical key actions for Unicode character input
  • Removed GLFWCALL and GLFWAPIENTRY macros for stdcall calling convention
  • Removed GLFW_ACCELERATED window parameter
  • Removed default framebuffer attributes from glfwGetWindowParam
  • Bugfix: The default OpenGL version in the glfwinfo test was set to 1.1
  • Bugfix: The OpenGL profile and forward-compatibility window parameters were not saved after context creation
  • Bugfix: The FSAA test did not check for the availability of GL_ARB_multisample
  • Bugfix: Cursor centering upon leaving captured cursor mode was reported before the mode was changed to non-captured
  • [Cocoa] Added support for OpenGL 3.2 core profile in 10.7 Lion and above
  • [Cocoa] Added support for joysticks
  • [Cocoa] Postponed menu creation to first window creation
  • [Cocoa] Replaced NSDate time source with mach_absolute_time
  • [Cocoa] Replaced all deprecated CoreGraphics calls with non-deprecated counterparts
  • [Cocoa] Bugfix: The NSOpenGLPFAFullScreen pixel format attribute caused creation to fail on some machines
  • [Cocoa] Bugfix: glfwOpenWindow did not properly enforce the forward-compatible and context profile hints
  • [Cocoa] Bugfix: The loop condition for saving video modes used the wrong index variable
  • [Cocoa] Bugfix: The OpenGL framework was not retrieved, making glfwGetProcAddress crash
  • [Cocoa] Bugfix: glfwInit changed the current directory for unbundled executables
  • [Cocoa] Bugfix: The GLFW_WINDOW_NO_RESIZE window parameter was always zero
  • [Cocoa] Bugfix: The cursor position incorrectly rounded during conversion
  • [Cocoa] Bugfix: Cursor positioning led to nonsensical results for fullscreen windows
  • [Cocoa] Bugfix: The GLFW window was flagged as restorable
  • [X11] Added support for the GLX_EXT_swap_control and GLX_MESA_swap_control extensions as alternatives to GLX_SGI_swap_control
  • [X11] Added the POSIX CLOCK_MONOTONIC time source as the preferred method
  • [X11] Added dependency on libm, where present
  • [X11] Added support for the _NET_WM_NAME and _NET_WM_ICON_NAME EWMH window properties
  • [X11] Made client-side RandR and Xf86VidMode extensions required
  • [X11] Bugfix: Some window properties required by the ICCCM were not set
  • [X11] Bugfix: Calling glXCreateContextAttribsARB with an unavailable OpenGL version caused the application to terminate with a BadMatch Xlib error
  • [X11] Bugfix: A synchronization point necessary for jitter-free locked cursor mode was incorrectly removed
  • [X11] Bugfix: The window size hints were not updated when calling glfwSetWindowSize on a non-resizable window
  • [Win32] Changed port to use Unicode mode only
  • [Win32] Removed explicit support for versions of Windows older than Windows XP
  • [Win32] Bugfix: Window activation and iconification did not work as expected
  • [Win32] Bugfix: Software rasterizer pixel formats were not discarded by the WGL_ARB_pixel_format code path
  • [Win32] Bugfix: The array for WGL context attributes was too small and could overflow
  • [Win32] Bugfix: Alt+F4 hot key was not translated into WM_CLOSE
  • [Win32] Bugfix: The GLFW_WINDOW_NO_RESIZE window parameter was always zero
  • [Win32] Bugfix: A test was missing for whether all available pixel formats had been disqualified

Contact

The official website for GLFW is glfw.org. There you can find the latest version of GLFW, as well as news, documentation and other information about the project.

If you have questions related to the use of GLFW, we have a support forum, and the IRC channel #glfw on Freenode.

If you have a bug to report, a patch to submit or a feature you'd like to request, please file it in one of the issue trackers on SF.net.

Finally, if you're interested in helping out with the development of GLFW or porting it to your favorite platform, we have a developer's mailing list, or you could join us on #glfw.

Acknowledgements

GLFW exists because people around the world donated their time and lent their skills.

  • Bobyshev Alexander
  • artblanc
  • Matt Arsenault
  • Keith Bauer
  • John Bartholomew
  • blanco
  • Lambert Clara
  • Noel Cower
  • Jarrod Davis
  • Olivier Delannoy
  • Paul R. Deppe
  • Jonathan Dummer
  • Ralph Eastwood
  • Gerald Franz
  • GeO4d
  • Marcus Geelnard
  • Stefan Gustavson
  • Sylvain Hellegouarch
  • heromyth
  • Toni Jovanoski
  • Osman Keskin
  • Cameron King
  • Peter Knut
  • Robin Leffmann
  • Glenn Lewis
  • Shane Liesegang
  • Дмитри Малышев
  • Martins Mozeiko
  • Tristam MacDonald
  • Hans Mackowiak
  • David Medlock
  • Jonathan Mercier
  • Marcel Metz
  • Kenneth Miller
  • Jeff Molofee
  • Jon Morton
  • Julian Møller
  • Ozzy at Orkysquad
  • Peoro
  • Braden Pellett
  • Arturo J. Pérez
  • Jorge Rodriguez
  • Ed Ropple
  • Riku Salminen
  • Sebastian Schuberth
  • Matt Sealey
  • SephiRok
  • Steve Sexton
  • Dmitri Shuralyov
  • Daniel Skorupski
  • Bradley Smith
  • Julian Squires
  • Johannes Stein
  • TTK-Bandit
  • Sergey Tikhomirov
  • Samuli Tuomola
  • Jari Vetoniemi
  • Simon Voordouw
  • Torsten Walluhn
  • Frank Wille
  • yuriks
  • Santi Zupancic
  • Lasse Öörni
  • All the unmentioned and anonymous contributors in the GLFW community, for bug reports, patches, feedback, testing and encouragement