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diff --git a/libs/glfw-3.3.8/docs/moving.dox b/libs/glfw-3.3.8/docs/moving.dox new file mode 100644 index 0000000..b80d84a --- /dev/null +++ b/libs/glfw-3.3.8/docs/moving.dox @@ -0,0 +1,513 @@ +/*! + +@page moving_guide Moving from GLFW 2 to 3 + +@tableofcontents + +This is a transition guide for moving from GLFW 2 to 3. It describes what has +changed or been removed, but does _not_ include +[new features](@ref news) unless they are required when moving an existing code +base onto the new API. For example, the new multi-monitor functions are +required to create full screen windows with GLFW 3. + + +@section moving_removed Changed and removed features + +@subsection moving_renamed_files Renamed library and header file + +The GLFW 3 header is named @ref glfw3.h and moved to the `GLFW` directory, to +avoid collisions with the headers of other major versions. Similarly, the GLFW +3 library is named `glfw3,` except when it's installed as a shared library on +Unix-like systems, where it uses the +[soname](https://en.wikipedia.org/wiki/soname) `libglfw.so.3`. + +@par Old syntax +@code +#include <GL/glfw.h> +@endcode + +@par New syntax +@code +#include <GLFW/glfw3.h> +@endcode + + +@subsection moving_threads Removal of threading functions + +The threading functions have been removed, including the per-thread sleep +function. They were fairly primitive, under-used, poorly integrated and took +time away from the focus of GLFW (i.e. context, input and window). There are +better threading libraries available and native threading support is available +in both [C++11](https://en.cppreference.com/w/cpp/thread) and +[C11](https://en.cppreference.com/w/c/thread), both of which are gaining +traction. + +If you wish to use the C++11 or C11 facilities but your compiler doesn't yet +support them, see the +[TinyThread++](https://gitorious.org/tinythread/tinythreadpp) and +[TinyCThread](https://github.com/tinycthread/tinycthread) projects created by +the original author of GLFW. These libraries implement a usable subset of the +threading APIs in C++11 and C11, and in fact some GLFW 3 test programs use +TinyCThread. + +However, GLFW 3 has better support for _use from multiple threads_ than GLFW +2 had. Contexts can be made current on any thread, although only a single +thread at a time, and the documentation explicitly states which functions may be +used from any thread and which must only be used from the main thread. + +@par Removed functions +`glfwSleep`, `glfwCreateThread`, `glfwDestroyThread`, `glfwWaitThread`, +`glfwGetThreadID`, `glfwCreateMutex`, `glfwDestroyMutex`, `glfwLockMutex`, +`glfwUnlockMutex`, `glfwCreateCond`, `glfwDestroyCond`, `glfwWaitCond`, +`glfwSignalCond`, `glfwBroadcastCond` and `glfwGetNumberOfProcessors`. + +@par Removed types +`GLFWthreadfun` + + +@subsection moving_image Removal of image and texture loading + +The image and texture loading functions have been removed. They only supported +the Targa image format, making them mostly useful for beginner level examples. +To become of sufficiently high quality to warrant keeping them in GLFW 3, they +would need not only to support other formats, but also modern extensions to +OpenGL texturing. This would either add a number of external +dependencies (libjpeg, libpng, etc.), or force GLFW to ship with inline versions +of these libraries. + +As there already are libraries doing this, it is unnecessary both to duplicate +the work and to tie the duplicate to GLFW. The resulting library would also be +platform-independent, as both OpenGL and stdio are available wherever GLFW is. + +@par Removed functions +`glfwReadImage`, `glfwReadMemoryImage`, `glfwFreeImage`, `glfwLoadTexture2D`, +`glfwLoadMemoryTexture2D` and `glfwLoadTextureImage2D`. + + +@subsection moving_stdcall Removal of GLFWCALL macro + +The `GLFWCALL` macro, which made callback functions use +[__stdcall](https://msdn.microsoft.com/en-us/library/zxk0tw93.aspx) on Windows, +has been removed. GLFW is written in C, not Pascal. Removing this macro means +there's one less thing for application programmers to remember, i.e. the +requirement to mark all callback functions with `GLFWCALL`. It also simplifies +the creation of DLLs and DLL link libraries, as there's no need to explicitly +disable `@n` entry point suffixes. + +@par Old syntax +@code +void GLFWCALL callback_function(...); +@endcode + +@par New syntax +@code +void callback_function(...); +@endcode + + +@subsection moving_window_handles Window handle parameters + +Because GLFW 3 supports multiple windows, window handle parameters have been +added to all window-related GLFW functions and callbacks. The handle of +a newly created window is returned by @ref glfwCreateWindow (formerly +`glfwOpenWindow`). Window handles are pointers to the +[opaque](https://en.wikipedia.org/wiki/Opaque_data_type) type @ref GLFWwindow. + +@par Old syntax +@code +glfwSetWindowTitle("New Window Title"); +@endcode + +@par New syntax +@code +glfwSetWindowTitle(window, "New Window Title"); +@endcode + + +@subsection moving_monitor Explicit monitor selection + +GLFW 3 provides support for multiple monitors. To request a full screen mode window, +instead of passing `GLFW_FULLSCREEN` you specify which monitor you wish the +window to use. The @ref glfwGetPrimaryMonitor function returns the monitor that +GLFW 2 would have selected, but there are many other +[monitor functions](@ref monitor_guide). Monitor handles are pointers to the +[opaque](https://en.wikipedia.org/wiki/Opaque_data_type) type @ref GLFWmonitor. + +@par Old basic full screen +@code +glfwOpenWindow(640, 480, 8, 8, 8, 0, 24, 0, GLFW_FULLSCREEN); +@endcode + +@par New basic full screen +@code +window = glfwCreateWindow(640, 480, "My Window", glfwGetPrimaryMonitor(), NULL); +@endcode + +@note The framebuffer bit depth parameters of `glfwOpenWindow` have been turned +into [window hints](@ref window_hints), but as they have been given +[sane defaults](@ref window_hints_values) you rarely need to set these hints. + + +@subsection moving_autopoll Removal of automatic event polling + +GLFW 3 does not automatically poll for events in @ref glfwSwapBuffers, meaning +you need to call @ref glfwPollEvents or @ref glfwWaitEvents yourself. Unlike +buffer swap, which acts on a single window, the event processing functions act +on all windows at once. + +@par Old basic main loop +@code +while (...) +{ + // Process input + // Render output + glfwSwapBuffers(); +} +@endcode + +@par New basic main loop +@code +while (...) +{ + // Process input + // Render output + glfwSwapBuffers(window); + glfwPollEvents(); +} +@endcode + + +@subsection moving_context Explicit context management + +Each GLFW 3 window has its own OpenGL context and only you, the application +programmer, can know which context should be current on which thread at any +given time. Therefore, GLFW 3 leaves that decision to you. + +This means that you need to call @ref glfwMakeContextCurrent after creating +a window before you can call any OpenGL functions. + + +@subsection moving_hidpi Separation of window and framebuffer sizes + +Window positions and sizes now use screen coordinates, which may not be the same +as pixels on machines with high-DPI monitors. This is important as OpenGL uses +pixels, not screen coordinates. For example, the rectangle specified with +`glViewport` needs to use pixels. Therefore, framebuffer size functions have +been added. You can retrieve the size of the framebuffer of a window with @ref +glfwGetFramebufferSize function. A framebuffer size callback has also been +added, which can be set with @ref glfwSetFramebufferSizeCallback. + +@par Old basic viewport setup +@code +glfwGetWindowSize(&width, &height); +glViewport(0, 0, width, height); +@endcode + +@par New basic viewport setup +@code +glfwGetFramebufferSize(window, &width, &height); +glViewport(0, 0, width, height); +@endcode + + +@subsection moving_window_close Window closing changes + +The `GLFW_OPENED` window parameter has been removed. As long as the window has +not been destroyed, whether through @ref glfwDestroyWindow or @ref +glfwTerminate, the window is "open". + +A user attempting to close a window is now just an event like any other. Unlike +GLFW 2, windows and contexts created with GLFW 3 will never be destroyed unless +you choose them to be. Each window now has a close flag that is set to +`GLFW_TRUE` when the user attempts to close that window. By default, nothing else +happens and the window stays visible. It is then up to you to either destroy +the window, take some other action or ignore the request. + +You can query the close flag at any time with @ref glfwWindowShouldClose and set +it at any time with @ref glfwSetWindowShouldClose. + +@par Old basic main loop +@code +while (glfwGetWindowParam(GLFW_OPENED)) +{ + ... +} +@endcode + +@par New basic main loop +@code +while (!glfwWindowShouldClose(window)) +{ + ... +} +@endcode + +The close callback no longer returns a value. Instead, it is called after the +close flag has been set so it can override its value, if it chooses to, before +event processing completes. You may however not call @ref glfwDestroyWindow +from the close callback (or any other window related callback). + +@par Old syntax +@code +int GLFWCALL window_close_callback(void); +@endcode + +@par New syntax +@code +void window_close_callback(GLFWwindow* window); +@endcode + +@note GLFW never clears the close flag to `GLFW_FALSE`, meaning you can use it +for other reasons to close the window as well, for example the user choosing +Quit from an in-game menu. + + +@subsection moving_hints Persistent window hints + +The `glfwOpenWindowHint` function has been renamed to @ref glfwWindowHint. + +Window hints are no longer reset to their default values on window creation, but +instead retain their values until modified by @ref glfwWindowHint or @ref +glfwDefaultWindowHints, or until the library is terminated and re-initialized. + + +@subsection moving_video_modes Video mode enumeration + +Video mode enumeration is now per-monitor. The @ref glfwGetVideoModes function +now returns all available modes for a specific monitor instead of requiring you +to guess how large an array you need. The `glfwGetDesktopMode` function, which +had poorly defined behavior, has been replaced by @ref glfwGetVideoMode, which +returns the current mode of a monitor. + + +@subsection moving_char_up Removal of character actions + +The action parameter of the [character callback](@ref GLFWcharfun) has been +removed. This was an artefact of the origin of GLFW, i.e. being developed in +English by a Swede. However, many keyboard layouts require more than one key to +produce characters with diacritical marks. Even the Swedish keyboard layout +requires this for uncommon cases like ΓΌ. + +@par Old syntax +@code +void GLFWCALL character_callback(int character, int action); +@endcode + +@par New syntax +@code +void character_callback(GLFWwindow* window, int character); +@endcode + + +@subsection moving_cursorpos Cursor position changes + +The `glfwGetMousePos` function has been renamed to @ref glfwGetCursorPos, +`glfwSetMousePos` to @ref glfwSetCursorPos and `glfwSetMousePosCallback` to @ref +glfwSetCursorPosCallback. + +The cursor position is now `double` instead of `int`, both for the direct +functions and for the callback. Some platforms can provide sub-pixel cursor +movement and this data is now passed on to the application where available. On +platforms where this is not provided, the decimal part is zero. + +GLFW 3 only allows you to position the cursor within a window using @ref +glfwSetCursorPos (formerly `glfwSetMousePos`) when that window is active. +Unless the window is active, the function fails silently. + + +@subsection moving_wheel Wheel position replaced by scroll offsets + +The `glfwGetMouseWheel` function has been removed. Scrolling is the input of +offsets and has no absolute position. The mouse wheel callback has been +replaced by a [scroll callback](@ref GLFWscrollfun) that receives +two-dimensional floating point scroll offsets. This allows you to receive +precise scroll data from for example modern touchpads. + +@par Old syntax +@code +void GLFWCALL mouse_wheel_callback(int position); +@endcode + +@par New syntax +@code +void scroll_callback(GLFWwindow* window, double xoffset, double yoffset); +@endcode + +@par Removed functions +`glfwGetMouseWheel` + + +@subsection moving_repeat Key repeat action + +The `GLFW_KEY_REPEAT` enable has been removed and key repeat is always enabled +for both keys and characters. A new key action, `GLFW_REPEAT`, has been added +to allow the [key callback](@ref GLFWkeyfun) to distinguish an initial key press +from a repeat. Note that @ref glfwGetKey still returns only `GLFW_PRESS` or +`GLFW_RELEASE`. + + +@subsection moving_keys Physical key input + +GLFW 3 key tokens map to physical keys, unlike in GLFW 2 where they mapped to +the values generated by the current keyboard layout. The tokens are named +according to the values they would have using the standard US layout, but this +is only a convenience, as most programmers are assumed to know that layout. +This means that (for example) `GLFW_KEY_LEFT_BRACKET` is always a single key and +is the same key in the same place regardless of what keyboard layouts the users +of your program has. + +The key input facility was never meant for text input, although using it that +way worked slightly better in GLFW 2. If you were using it to input text, you +should be using the character callback instead, on both GLFW 2 and 3. This will +give you the characters being input, as opposed to the keys being pressed. + +GLFW 3 has key tokens for all keys on a standard 105 key keyboard, so instead of +having to remember whether to check for `a` or `A`, you now check for +@ref GLFW_KEY_A. + + +@subsection moving_joystick Joystick function changes + +The `glfwGetJoystickPos` function has been renamed to @ref glfwGetJoystickAxes. + +The `glfwGetJoystickParam` function and the `GLFW_PRESENT`, `GLFW_AXES` and +`GLFW_BUTTONS` tokens have been replaced by the @ref glfwJoystickPresent +function as well as axis and button counts returned by the @ref +glfwGetJoystickAxes and @ref glfwGetJoystickButtons functions. + + +@subsection moving_mbcs Win32 MBCS support + +The Win32 port of GLFW 3 will not compile in +[MBCS mode](https://msdn.microsoft.com/en-us/library/5z097dxa.aspx). +However, because the use of the Unicode version of the Win32 API doesn't affect +the process as a whole, but only those windows created using it, it's perfectly +possible to call MBCS functions from other parts of the same application. +Therefore, even if an application using GLFW has MBCS mode code, there's no need +for GLFW itself to support it. + + +@subsection moving_windows Support for versions of Windows older than XP + +All explicit support for version of Windows older than XP has been removed. +There is no code that actively prevents GLFW 3 from running on these earlier +versions, but it uses Win32 functions that those versions lack. + +Windows XP was released in 2001, and by now (January 2015) it has not only +replaced almost all earlier versions of Windows, but is itself rapidly being +replaced by Windows 7 and 8. The MSDN library doesn't even provide +documentation for version older than Windows 2000, making it difficult to +maintain compatibility with these versions even if it was deemed worth the +effort. + +The Win32 API has also not stood still, and GLFW 3 uses many functions only +present on Windows XP or later. Even supporting an OS as new as XP (new +from the perspective of GLFW 2, which still supports Windows 95) requires +runtime checking for a number of functions that are present only on modern +version of Windows. + + +@subsection moving_syskeys Capture of system-wide hotkeys + +The ability to disable and capture system-wide hotkeys like Alt+Tab has been +removed. Modern applications, whether they're games, scientific visualisations +or something else, are nowadays expected to be good desktop citizens and allow +these hotkeys to function even when running in full screen mode. + + +@subsection moving_terminate Automatic termination + +GLFW 3 does not register @ref glfwTerminate with `atexit` at initialization, +because `exit` calls registered functions from the calling thread and while it +is permitted to call `exit` from any thread, @ref glfwTerminate must only be +called from the main thread. + +To release all resources allocated by GLFW, you should call @ref glfwTerminate +yourself, from the main thread, before the program terminates. Note that this +destroys all windows not already destroyed with @ref glfwDestroyWindow, +invalidating any window handles you may still have. + + +@subsection moving_glu GLU header inclusion + +GLFW 3 does not by default include the GLU header and GLU itself has been +deprecated by [Khronos](https://en.wikipedia.org/wiki/Khronos_Group). __New +projects should not use GLU__, but if you need it for legacy code that +has been moved to GLFW 3, you can request that the GLFW header includes it by +defining @ref GLFW_INCLUDE_GLU before the inclusion of the GLFW header. + +@par Old syntax +@code +#include <GL/glfw.h> +@endcode + +@par New syntax +@code +#define GLFW_INCLUDE_GLU +#include <GLFW/glfw3.h> +@endcode + +There are many libraries that offer replacements for the functionality offered +by GLU. For the matrix helper functions, see math libraries like +[GLM](https://github.com/g-truc/glm) (for C++), +[linmath.h](https://github.com/datenwolf/linmath.h) (for C) and others. For the +tessellation functions, see for example +[libtess2](https://github.com/memononen/libtess2). + + +@section moving_tables Name change tables + + +@subsection moving_renamed_functions Renamed functions + +| GLFW 2 | GLFW 3 | Notes | +| --------------------------- | ----------------------------- | ----- | +| `glfwOpenWindow` | @ref glfwCreateWindow | All channel bit depths are now hints +| `glfwCloseWindow` | @ref glfwDestroyWindow | | +| `glfwOpenWindowHint` | @ref glfwWindowHint | Now accepts all `GLFW_*_BITS` tokens | +| `glfwEnable` | @ref glfwSetInputMode | | +| `glfwDisable` | @ref glfwSetInputMode | | +| `glfwGetMousePos` | @ref glfwGetCursorPos | | +| `glfwSetMousePos` | @ref glfwSetCursorPos | | +| `glfwSetMousePosCallback` | @ref glfwSetCursorPosCallback | | +| `glfwSetMouseWheelCallback` | @ref glfwSetScrollCallback | Accepts two-dimensional scroll offsets as doubles | +| `glfwGetJoystickPos` | @ref glfwGetJoystickAxes | | +| `glfwGetWindowParam` | @ref glfwGetWindowAttrib | | +| `glfwGetGLVersion` | @ref glfwGetWindowAttrib | Use `GLFW_CONTEXT_VERSION_MAJOR`, `GLFW_CONTEXT_VERSION_MINOR` and `GLFW_CONTEXT_REVISION` | +| `glfwGetDesktopMode` | @ref glfwGetVideoMode | Returns the current mode of a monitor | +| `glfwGetJoystickParam` | @ref glfwJoystickPresent | The axis and button counts are provided by @ref glfwGetJoystickAxes and @ref glfwGetJoystickButtons | + + +@subsection moving_renamed_types Renamed types + +| GLFW 2 | GLFW 3 | Notes | +| ------------------- | --------------------- | | +| `GLFWmousewheelfun` | @ref GLFWscrollfun | | +| `GLFWmouseposfun` | @ref GLFWcursorposfun | | + + +@subsection moving_renamed_tokens Renamed tokens + +| GLFW 2 | GLFW 3 | Notes | +| --------------------------- | ---------------------------- | ----- | +| `GLFW_OPENGL_VERSION_MAJOR` | `GLFW_CONTEXT_VERSION_MAJOR` | Renamed as it applies to OpenGL ES as well | +| `GLFW_OPENGL_VERSION_MINOR` | `GLFW_CONTEXT_VERSION_MINOR` | Renamed as it applies to OpenGL ES as well | +| `GLFW_FSAA_SAMPLES` | `GLFW_SAMPLES` | Renamed to match the OpenGL API | +| `GLFW_ACTIVE` | `GLFW_FOCUSED` | Renamed to match the window focus callback | +| `GLFW_WINDOW_NO_RESIZE` | `GLFW_RESIZABLE` | The default has been inverted | +| `GLFW_MOUSE_CURSOR` | `GLFW_CURSOR` | Used with @ref glfwSetInputMode | +| `GLFW_KEY_ESC` | `GLFW_KEY_ESCAPE` | | +| `GLFW_KEY_DEL` | `GLFW_KEY_DELETE` | | +| `GLFW_KEY_PAGEUP` | `GLFW_KEY_PAGE_UP` | | +| `GLFW_KEY_PAGEDOWN` | `GLFW_KEY_PAGE_DOWN` | | +| `GLFW_KEY_KP_NUM_LOCK` | `GLFW_KEY_NUM_LOCK` | | +| `GLFW_KEY_LCTRL` | `GLFW_KEY_LEFT_CONTROL` | | +| `GLFW_KEY_LSHIFT` | `GLFW_KEY_LEFT_SHIFT` | | +| `GLFW_KEY_LALT` | `GLFW_KEY_LEFT_ALT` | | +| `GLFW_KEY_LSUPER` | `GLFW_KEY_LEFT_SUPER` | | +| `GLFW_KEY_RCTRL` | `GLFW_KEY_RIGHT_CONTROL` | | +| `GLFW_KEY_RSHIFT` | `GLFW_KEY_RIGHT_SHIFT` | | +| `GLFW_KEY_RALT` | `GLFW_KEY_RIGHT_ALT` | | +| `GLFW_KEY_RSUPER` | `GLFW_KEY_RIGHT_SUPER` | | + +*/ |