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902 lines
34 KiB
Plaintext
902 lines
34 KiB
Plaintext
/*!
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@page window Window guide
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@tableofcontents
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This guide introduces the window related functions of GLFW. There are also
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guides for the other areas of GLFW.
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- @ref intro
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- @ref context
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- @ref monitor
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- @ref input
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@section window_object Window objects
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The @ref GLFWwindow object encapsulates both a window and a context. They are
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created with @ref glfwCreateWindow and destroyed with @ref glfwDestroyWindow, or
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@ref glfwTerminate, if any remain. As the window and context are inseparably
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linked, the object pointer is used as both a context and window handle.
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To see the event stream provided to the various window related callbacks, run
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the `events` test program.
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@subsection window_creation Window creation
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A window and its OpenGL or OpenGL ES context are created with @ref
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glfwCreateWindow, which returns a handle to the created window object. For
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example, this creates a 640 by 480 windowed mode window:
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@code
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GLFWwindow* window = glfwCreateWindow(640, 480, "My Title", NULL, NULL);
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@endcode
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If window creation fails, `NULL` will be returned, so it is necessary to check
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the return value.
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The window handle is passed to all window related functions and is provided to
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along with all input events, so event handlers can tell which window received
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the event.
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@subsubsection window_full_screen Full screen windows
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To create a full screen window, you need to specify which monitor the window
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should use. In most cases, the user's primary monitor is a good choice.
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For more information about retrieving monitors, see @ref monitor_monitors.
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@code
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GLFWwindow* window = glfwCreateWindow(640, 480, "My Title", glfwGetPrimaryMonitor(), NULL);
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@endcode
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Full screen windows cover the entire display area of a monitor, have no border
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or decorations.
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Each field of the @ref GLFWvidmode structure corresponds to a function parameter
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or window hint and combine to form the _desired video mode_ for that window.
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The supported video mode most closely matching the desired video mode will be
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set for the chosen monitor as long as the window has input focus. For more
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information about retrieving video modes, see @ref monitor_modes.
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Video mode field | Corresponds to
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----------------------- | ------------------------
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GLFWvidmode.width | `width` parameter
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GLFWvidmode.height | `height` parameter
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GLFWvidmode.redBits | `GLFW_RED_BITS` hint
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GLFWvidmode.greenBits | `GLFW_GREEN_BITS` hint
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GLFWvidmode.blueBits | `GLFW_BLUE_BITS` hint
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GLFWvidmode.refreshRate | `GLFW_REFRESH_RATE` hint
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Once you have a full screen window, you can change its resolution with @ref
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glfwSetWindowSize. The new video mode will be selected and set the same way as
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the video mode chosen by @ref glfwCreateWindow.
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By default, the original video mode of the monitor will be restored and the
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window iconified if it loses input focus, to allow the user to switch back to
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the desktop. This behavior can be disabled with the `GLFW_AUTO_ICONIFY` window
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hint, for example if you wish to simultaneously cover multiple windows with full
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screen windows.
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@subsubsection window_windowed_full_screen "Windowed full screen" windows
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If the closest match for the desired video mode is the current one, the video
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mode will not be changed, making window creation faster and application
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switching much smoother. This is sometimes called _windowed full screen_ or
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_borderless full screen_ window and counts as a full screen window. To create
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such a window, simply request the current video mode.
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@code
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const GLFWvidmode* mode = glfwGetVideoMode(monitor);
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glfwWindowHint(GLFW_RED_BITS, mode->redBits);
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glfwWindowHint(GLFW_GREEN_BITS, mode->greenBits);
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glfwWindowHint(GLFW_BLUE_BITS, mode->blueBits);
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glfwWindowHint(GLFW_REFRESH_RATE, mode->refreshRate);
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GLFWwindow* window = glfwCreateWindow(mode->width, mode->height, "My Title", monitor, NULL);
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@endcode
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@subsection window_destruction Window destruction
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When a window is no longer needed, destroy it with @ref glfwDestroyWindow.
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@code
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glfwDestroyWindow(window);
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@endcode
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Window destruction always succeeds. Before the actual destruction, all
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callbacks are removed so no further events will be delivered for the window.
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All windows remaining when @ref glfwTerminate is called are destroyed as well.
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When a full screen window is destroyed, the original video mode of its monitor
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is restored, but the gamma ramp is left untouched.
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@subsection window_hints Window creation hints
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There are a number of hints that can be set before the creation of a window and
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context. Some affect the window itself, others affect the framebuffer or
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context. These hints are set to their default values each time the library is
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initialized with @ref glfwInit, can be set individually with @ref glfwWindowHint
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and reset all at once to their defaults with @ref glfwDefaultWindowHints.
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Note that hints need to be set _before_ the creation of the window and context
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you wish to have the specified attributes.
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@subsubsection window_hints_hard Hard and soft constraints
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Some window hints are hard constraints. These must match the available
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capabilities _exactly_ for window and context creation to succeed. Hints
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that are not hard constraints are matched as closely as possible, but the
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resulting context and framebuffer may differ from what these hints requested.
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The following hints are always hard constraints:
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- `GLFW_STEREO`
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- `GLFW_DOUBLEBUFFER`
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- `GLFW_CLIENT_API`
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The following additional hints are hard constraints when requesting an OpenGL
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context, but are ignored when requesting an OpenGL ES context:
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- `GLFW_OPENGL_FORWARD_COMPAT`
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- `GLFW_OPENGL_PROFILE`
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@subsubsection window_hints_wnd Window related hints
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`GLFW_RESIZABLE` specifies whether the windowed mode window will be resizable
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_by the user_. The window will still be resizable using the @ref
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glfwSetWindowSize function. This hint is ignored for full screen windows.
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`GLFW_VISIBLE` specifies whether the windowed mode window will be initially
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visible. This hint is ignored for full screen windows.
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`GLFW_DECORATED` specifies whether the windowed mode window will have window
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decorations such as a border, a close widget, etc. An undecorated window may
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still allow the user to generate close events on some platforms. This hint is
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ignored for full screen windows.
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`GLFW_FOCUSED` specifies whether the windowed mode window will be given input
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focus when created. This hint is ignored for full screen and initially hidden
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windows.
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`GLFW_AUTO_ICONIFY` specifies whether the full screen window will
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automatically iconify and restore the previous video mode on input focus loss.
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This hint is ignored for windowed mode windows.
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`GLFW_FLOATING` specifies whether the windowed mode window will be floating
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above other regular windows, also called topmost or always-on-top. This is
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intended primarily for debugging purposes and cannot be used to implement proper
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full screen windows. This hint is ignored for full screen windows.
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@subsubsection window_hints_fb Framebuffer related hints
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`GLFW_RED_BITS`, `GLFW_GREEN_BITS`, `GLFW_BLUE_BITS`, `GLFW_ALPHA_BITS`,
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`GLFW_DEPTH_BITS` and `GLFW_STENCIL_BITS` specify the desired bit depths of the
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various components of the default framebuffer. `GLFW_DONT_CARE` means the
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application has no preference.
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`GLFW_ACCUM_RED_BITS`, `GLFW_ACCUM_GREEN_BITS`, `GLFW_ACCUM_BLUE_BITS` and
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`GLFW_ACCUM_ALPHA_BITS` specify the desired bit depths of the various components
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of the accumulation buffer. `GLFW_DONT_CARE` means the application has no
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preference.
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@par
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Accumulation buffers are a legacy OpenGL feature and should not be used in new
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code.
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`GLFW_AUX_BUFFERS` specifies the desired number of auxiliary buffers.
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`GLFW_DONT_CARE` means the application has no preference.
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@par
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Auxiliary buffers are a legacy OpenGL feature and should not be used in new
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code.
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`GLFW_STEREO` specifies whether to use stereoscopic rendering. This is a hard
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constraint.
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`GLFW_SAMPLES` specifies the desired number of samples to use for multisampling.
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Zero disables multisampling. `GLFW_DONT_CARE` means the application has no
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preference.
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`GLFW_SRGB_CAPABLE` specifies whether the framebuffer should be sRGB capable.
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If supported, the created context will provide `GL_ARB_framebuffer_sRGB` or
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`GL_EXT_framebuffer_sRGB`.
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`GLFW_DOUBLEBUFFER` specifies whether the framebuffer should be double buffered.
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You nearly always want to use double buffering. This is a hard constraint.
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@subsubsection window_hints_mtr Monitor related hints
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`GLFW_REFRESH_RATE` specifies the desired refresh rate for full screen windows.
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If set to `GLFW_DONT_CARE`, the highest available refresh rate will be used.
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This hint is ignored for windowed mode windows.
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@subsubsection window_hints_ctx Context related hints
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`GLFW_CLIENT_API` specifies which client API to create the context for.
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Possible values are `GLFW_OPENGL_API`, `GLFW_OPENGL_ES_API` and `GLFW_NO_API`.
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This is a hard constraint.
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`GLFW_CONTEXT_VERSION_MAJOR` and `GLFW_CONTEXT_VERSION_MINOR` specify the client
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API version that the created context must be compatible with. The exact
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behavior of these hints depend on the requested client API.
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@par
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__OpenGL:__ `GLFW_CONTEXT_VERSION_MAJOR` and `GLFW_CONTEXT_VERSION_MINOR` are not hard
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constraints, but creation will fail if the OpenGL version of the created context
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is less than the one requested. It is therefore perfectly safe to use the
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default of version 1.0 for legacy code and you may still get
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backwards-compatible contexts of version 3.0 and above when available.
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@par
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While there is no way to ask the driver for a context of the highest supported
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version, GLFW will attempt to provide this when you ask for a version 1.0
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context, which is the default for these hints.
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@par
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__OpenGL ES:__ `GLFW_CONTEXT_VERSION_MAJOR` and `GLFW_CONTEXT_VERSION_MINOR` are not hard
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constraints, but creation will fail if the OpenGL ES version of the created
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context is less than the one requested. Additionally, OpenGL ES 1.x cannot be
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returned if 2.0 or later was requested, and vice versa. This is because OpenGL
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ES 3.x is backward compatible with 2.0, but OpenGL ES 2.0 is not backward
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compatible with 1.x.
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`GLFW_OPENGL_FORWARD_COMPAT` specifies whether the OpenGL context should be
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forward-compatible, i.e. one where all functionality deprecated in the requested
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version of OpenGL is removed. This may only be used if the requested OpenGL
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version is 3.0 or above. If OpenGL ES is requested, this hint is ignored.
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@par
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Forward-compatibility is described in detail in the
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[OpenGL Reference Manual](https://www.opengl.org/registry/).
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`GLFW_OPENGL_DEBUG_CONTEXT` specifies whether to create a debug OpenGL context,
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which may have additional error and performance issue reporting functionality.
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If OpenGL ES is requested, this hint is ignored.
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`GLFW_OPENGL_PROFILE` specifies which OpenGL profile to create the context for.
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Possible values are one of `GLFW_OPENGL_CORE_PROFILE` or
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`GLFW_OPENGL_COMPAT_PROFILE`, or `GLFW_OPENGL_ANY_PROFILE` to not request
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a specific profile. If requesting an OpenGL version below 3.2,
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`GLFW_OPENGL_ANY_PROFILE` must be used. If OpenGL ES is requested,
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this hint is ignored.
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@par
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OpenGL profiles are described in detail in the
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[OpenGL Reference Manual](https://www.opengl.org/registry/).
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`GLFW_CONTEXT_ROBUSTNESS` specifies the robustness strategy to be used by the
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context. This can be one of `GLFW_NO_RESET_NOTIFICATION` or
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`GLFW_LOSE_CONTEXT_ON_RESET`, or `GLFW_NO_ROBUSTNESS` to not request
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a robustness strategy.
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`GLFW_CONTEXT_RELEASE_BEHAVIOR` specifies the release behavior to be
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used by the context. Possible values are one of `GLFW_ANY_RELEASE_BEHAVIOR`,
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`GLFW_RELEASE_BEHAVIOR_FLUSH` or `GLFW_RELEASE_BEHAVIOR_NONE`. If the
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behavior is `GLFW_ANY_RELEASE_BEHAVIOR`, the default behavior of the context
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creation API will be used. If the behavior is `GLFW_RELEASE_BEHAVIOR_FLUSH`,
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the pipeline will be flushed whenever the context is released from being the
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current one. If the behavior is `GLFW_RELEASE_BEHAVIOR_NONE`, the pipeline will
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not be flushed on release.
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@par
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Context release behaviors are described in detail by the
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[GL_KHR_context_flush_control](https://www.opengl.org/registry/specs/KHR/context_flush_control.txt)
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extension.
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`GLFW_CONTEXT_NO_ERROR` specifies whether errors should be generated by the
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context. If enabled, situations that would have generated errors instead cause
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undefined behavior.
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@par
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The no error mode for OpenGL and OpenGL ES is described in detail by the
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[GL_KHR_no_error](https://www.opengl.org/registry/specs/KHR/no_error.txt)
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extension.
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@note This hint is experimental in its current state. There are currently
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(October 2015) no corresponding WGL or GLX extensions. That makes this hint
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a [hard constraint](@ref window_hints_hard) for those backends, as creation will
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fail if unsupported context flags are requested. Once the extensions are
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available, they will be required and creation of `GL_KHR_no_error` contexts may
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fail on early drivers where this flag is supported without those extensions
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being listed.
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@subsubsection window_hints_values Supported and default values
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Window hint | Default value | Supported values
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------------------------------- | --------------------------- | ----------------
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`GLFW_RESIZABLE` | `GLFW_TRUE` | `GLFW_TRUE` or `GLFW_FALSE`
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`GLFW_VISIBLE` | `GLFW_TRUE` | `GLFW_TRUE` or `GLFW_FALSE`
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`GLFW_DECORATED` | `GLFW_TRUE` | `GLFW_TRUE` or `GLFW_FALSE`
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`GLFW_FOCUSED` | `GLFW_TRUE` | `GLFW_TRUE` or `GLFW_FALSE`
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`GLFW_AUTO_ICONIFY` | `GLFW_TRUE` | `GLFW_TRUE` or `GLFW_FALSE`
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`GLFW_FLOATING` | `GLFW_FALSE` | `GLFW_TRUE` or `GLFW_FALSE`
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`GLFW_RED_BITS` | 8 | 0 to `INT_MAX` or `GLFW_DONT_CARE`
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`GLFW_GREEN_BITS` | 8 | 0 to `INT_MAX` or `GLFW_DONT_CARE`
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`GLFW_BLUE_BITS` | 8 | 0 to `INT_MAX` or `GLFW_DONT_CARE`
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`GLFW_ALPHA_BITS` | 8 | 0 to `INT_MAX` or `GLFW_DONT_CARE`
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`GLFW_DEPTH_BITS` | 24 | 0 to `INT_MAX` or `GLFW_DONT_CARE`
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`GLFW_STENCIL_BITS` | 8 | 0 to `INT_MAX` or `GLFW_DONT_CARE`
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`GLFW_ACCUM_RED_BITS` | 0 | 0 to `INT_MAX` or `GLFW_DONT_CARE`
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`GLFW_ACCUM_GREEN_BITS` | 0 | 0 to `INT_MAX` or `GLFW_DONT_CARE`
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`GLFW_ACCUM_BLUE_BITS` | 0 | 0 to `INT_MAX` or `GLFW_DONT_CARE`
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`GLFW_ACCUM_ALPHA_BITS` | 0 | 0 to `INT_MAX` or `GLFW_DONT_CARE`
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`GLFW_AUX_BUFFERS` | 0 | 0 to `INT_MAX` or `GLFW_DONT_CARE`
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`GLFW_SAMPLES` | 0 | 0 to `INT_MAX` or `GLFW_DONT_CARE`
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`GLFW_REFRESH_RATE` | `GLFW_DONT_CARE` | 0 to `INT_MAX` or `GLFW_DONT_CARE`
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`GLFW_STEREO` | `GLFW_FALSE` | `GLFW_TRUE` or `GLFW_FALSE`
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`GLFW_SRGB_CAPABLE` | `GLFW_FALSE` | `GLFW_TRUE` or `GLFW_FALSE`
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`GLFW_DOUBLEBUFFER` | `GLFW_TRUE` | `GLFW_TRUE` or `GLFW_FALSE`
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`GLFW_CLIENT_API` | `GLFW_OPENGL_API` | `GLFW_OPENGL_API`, `GLFW_OPENGL_ES_API` or `GLFW_NO_API`
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`GLFW_CONTEXT_VERSION_MAJOR` | 1 | Any valid major version number of the chosen client API
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`GLFW_CONTEXT_VERSION_MINOR` | 0 | Any valid minor version number of the chosen client API
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`GLFW_CONTEXT_ROBUSTNESS` | `GLFW_NO_ROBUSTNESS` | `GLFW_NO_ROBUSTNESS`, `GLFW_NO_RESET_NOTIFICATION` or `GLFW_LOSE_CONTEXT_ON_RESET`
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`GLFW_CONTEXT_RELEASE_BEHAVIOR` | `GLFW_ANY_RELEASE_BEHAVIOR` | `GLFW_ANY_RELEASE_BEHAVIOR`, `GLFW_RELEASE_BEHAVIOR_FLUSH` or `GLFW_RELEASE_BEHAVIOR_NONE`
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`GLFW_OPENGL_FORWARD_COMPAT` | `GLFW_FALSE` | `GLFW_TRUE` or `GLFW_FALSE`
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`GLFW_OPENGL_DEBUG_CONTEXT` | `GLFW_FALSE` | `GLFW_TRUE` or `GLFW_FALSE`
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`GLFW_OPENGL_PROFILE` | `GLFW_OPENGL_ANY_PROFILE` | `GLFW_OPENGL_ANY_PROFILE`, `GLFW_OPENGL_COMPAT_PROFILE` or `GLFW_OPENGL_CORE_PROFILE`
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@section window_events Window event processing
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See @ref events.
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@section window_properties Window properties and events
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@subsection window_userptr User pointer
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Each window has a user pointer that can be set with @ref
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glfwSetWindowUserPointer and fetched with @ref glfwGetWindowUserPointer. This
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can be used for any purpose you need and will not be modified by GLFW throughout
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the life-time of the window.
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The initial value of the pointer is `NULL`.
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@subsection window_close Window closing and close flag
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When the user attempts to close the window, for example by clicking the close
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widget or using a key chord like Alt+F4, the _close flag_ of the window is set.
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The window is however not actually destroyed and, unless you watch for this
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state change, nothing further happens.
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The current state of the close flag is returned by @ref glfwWindowShouldClose
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and can be set or cleared directly with @ref glfwSetWindowShouldClose. A common
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pattern is to use the close flag as a main loop condition.
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@code
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while (!glfwWindowShouldClose(window))
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{
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render(window);
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glfwSwapBuffers(window);
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glfwPollEvents();
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}
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@endcode
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If you wish to be notified when the user attempts to close a window, set a close
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callback.
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@code
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glfwSetWindowCloseCallback(window, window_close_callback);
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@endcode
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The callback function is called directly _after_ the close flag has been set.
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It can be used for example to filter close requests and clear the close flag
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again unless certain conditions are met.
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@code
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void window_close_callback(GLFWwindow* window)
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{
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if (!time_to_close)
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glfwSetWindowShouldClose(window, GLFW_FALSE);
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}
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@endcode
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@subsection window_size Window size
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The size of a window can be changed with @ref glfwSetWindowSize. For windowed
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mode windows, this sets the size, in
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[screen coordinates](@ref coordinate_systems) of the _client area_ or _content
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area_ of the window. The window system may impose limits on window size.
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@code
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glfwSetWindowSize(window, 640, 480);
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@endcode
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For full screen windows, the specified size becomes the new resolution of the
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window's *desired video mode*. The video mode most closely matching the new
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desired video mode is set immediately. The window is resized to fit the
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resolution of the set video mode.
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If you wish to be notified when a window is resized, whether by the user or
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the system, set a size callback.
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@code
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glfwSetWindowSizeCallback(window, window_size_callback);
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@endcode
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The callback function receives the new size, in screen coordinates, of the
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client area of the window when it is resized.
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@code
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|
void window_size_callback(GLFWwindow* window, int width, int height)
|
|
{
|
|
}
|
|
@endcode
|
|
|
|
There is also @ref glfwGetWindowSize for directly retrieving the current size of
|
|
a window.
|
|
|
|
@code
|
|
int width, height;
|
|
glfwGetWindowSize(window, &width, &height);
|
|
@endcode
|
|
|
|
@note Do not pass the window size to `glViewport` or other pixel-based OpenGL
|
|
calls. The window size is in screen coordinates, not pixels. Use the
|
|
[framebuffer size](@ref window_fbsize), which is in pixels, for pixel-based
|
|
calls.
|
|
|
|
The above functions work with the size of the client area, but decorated windows
|
|
typically have title bars and window frames around this rectangle. You can
|
|
retrieve the extents of these with @ref glfwGetWindowFrameSize.
|
|
|
|
@code
|
|
int left, top, right, bottom;
|
|
glfwGetWindowFrameSize(window, &left, &top, &right, &bottom);
|
|
@endcode
|
|
|
|
The returned values are the distances, in screen coordinates, from the edges of
|
|
the client area to the corresponding edges of the full window. As they are
|
|
distances and not coordinates, they are always zero or positive.
|
|
|
|
|
|
@subsection window_fbsize Framebuffer size
|
|
|
|
While the size of a window is measured in screen coordinates, OpenGL works with
|
|
pixels. The size you pass into `glViewport`, for example, should be in pixels.
|
|
On some machines screen coordinates and pixels are the same, but on others they
|
|
will not be. There is a second set of functions to retrieve the size, in
|
|
pixels, of the framebuffer of a window.
|
|
|
|
If you wish to be notified when the framebuffer of a window is resized, whether
|
|
by the user or the system, set a size callback.
|
|
|
|
@code
|
|
glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
|
|
@endcode
|
|
|
|
The callback function receives the new size of the framebuffer when it is
|
|
resized, which can for example be used to update the OpenGL viewport.
|
|
|
|
@code
|
|
void framebuffer_size_callback(GLFWwindow* window, int width, int height)
|
|
{
|
|
glViewport(0, 0, width, height);
|
|
}
|
|
@endcode
|
|
|
|
There is also @ref glfwGetFramebufferSize for directly retrieving the current
|
|
size of the framebuffer of a window.
|
|
|
|
@code
|
|
int width, height;
|
|
glfwGetFramebufferSize(window, &width, &height);
|
|
glViewport(0, 0, width, height);
|
|
@endcode
|
|
|
|
The size of a framebuffer may change independently of the size of a window, for
|
|
example if the window is dragged between a regular monitor and a high-DPI one.
|
|
|
|
|
|
@subsection window_sizelimits Window size limits
|
|
|
|
The minimum and maximum size of the client area of a windowed mode window can be
|
|
enforced with @ref glfwSetWindowSizeLimits. The user may resize the window to
|
|
any size and aspect ratio within the specified limits, unless the aspect ratio
|
|
is also set.
|
|
|
|
@code
|
|
glfwSetWindowSizeLimits(window, 200, 200, 400, 400);
|
|
@endcode
|
|
|
|
To specify only a minimum size or only a maximum one, set the other pair to
|
|
`GLFW_DONT_CARE`.
|
|
|
|
@code
|
|
glfwSetWindowSizeLimits(window, 640, 480, GLFW_DONT_CARE, GLFW_DONT_CARE);
|
|
@endcode
|
|
|
|
To disable size limits for a window, set them all to `GLFW_DONT_CARE`.
|
|
|
|
The aspect ratio of the client area of a windowed mode window can be enforced
|
|
with @ref glfwSetWindowAspectRatio. The user may resize the window freely
|
|
unless size limits are also set, but the size will be constrained to maintain
|
|
the aspect ratio.
|
|
|
|
@code
|
|
glfwSetWindowAspectRatio(window, 16, 9);
|
|
@endcode
|
|
|
|
The aspect ratio is specified as a numerator and denominator, corresponding to
|
|
the width and height, respectively. If you want a window to maintain its
|
|
current aspect ratio, simply use its current size as the ratio.
|
|
|
|
@code
|
|
int width, height;
|
|
glfwGetWindowSize(window, &width, &height);
|
|
glfwSetWindowAspectRatio(window, width, height);
|
|
@endcode
|
|
|
|
To disable the aspect ratio limit for a window, set both terms to
|
|
`GLFW_DONT_CARE`.
|
|
|
|
You can have both size limits and aspect ratio set for a window, but the results
|
|
are undefined if they conflict.
|
|
|
|
|
|
@subsection window_pos Window position
|
|
|
|
The position of a windowed-mode window can be changed with @ref
|
|
glfwSetWindowPos. This moves the window so that the upper-left corner of its
|
|
client area has the specified [screen coordinates](@ref coordinate_systems).
|
|
The window system may put limitations on window placement.
|
|
|
|
@code
|
|
glfwSetWindowPos(window, 100, 100);
|
|
@endcode
|
|
|
|
If you wish to be notified when a window is moved, whether by the user, system
|
|
or your own code, set a position callback.
|
|
|
|
@code
|
|
glfwSetWindowPosCallback(window, window_pos_callback);
|
|
@endcode
|
|
|
|
The callback function receives the new position of the upper-left corner of the
|
|
client area when the window is moved.
|
|
|
|
@code
|
|
void window_pos_callback(GLFWwindow* window, int xpos, int ypos)
|
|
{
|
|
}
|
|
@endcode
|
|
|
|
There is also @ref glfwGetWindowPos for directly retrieving the current position
|
|
of the client area of the window.
|
|
|
|
@code
|
|
int xpos, ypos;
|
|
glfwGetWindowPos(window, &xpos, &ypos);
|
|
@endcode
|
|
|
|
|
|
@subsection window_title Window title
|
|
|
|
All GLFW windows have a title, although undecorated or full screen windows may
|
|
not display it or only display it in a task bar or similar interface. You can
|
|
set a UTF-8 encoded window title with @ref glfwSetWindowTitle.
|
|
|
|
@code
|
|
glfwSetWindowTitle(window, "My Window");
|
|
@endcode
|
|
|
|
The specified string is copied before the function returns, so there is no need
|
|
to keep it around.
|
|
|
|
As long as your source file is encoded as UTF-8, you can use any Unicode
|
|
characters directly in the source.
|
|
|
|
@code
|
|
glfwSetWindowTitle(window, "星を追う子ども");
|
|
@endcode
|
|
|
|
If you are using C++11 or C11, you can use a UTF-8 string literal.
|
|
|
|
@code
|
|
glfwSetWindowTitle(window, u8"This is always a UTF-8 string");
|
|
@endcode
|
|
|
|
|
|
@subsection window_monitor Window monitor
|
|
|
|
Full screen windows are associated with a specific monitor. You can get the
|
|
handle for this monitor with @ref glfwGetWindowMonitor.
|
|
|
|
@code
|
|
GLFWmonitor* monitor = glfwGetWindowMonitor(window);
|
|
@endcode
|
|
|
|
This monitor handle is one of those returned by @ref glfwGetMonitors.
|
|
|
|
For windowed mode windows, this function returns `NULL`. This is the
|
|
recommended way to tell full screen windows from windowed mode windows.
|
|
|
|
|
|
@subsection window_iconify Window iconification
|
|
|
|
Windows can be iconified (i.e. minimized) with @ref glfwIconifyWindow.
|
|
|
|
@code
|
|
glfwIconifyWindow(window);
|
|
@endcode
|
|
|
|
When a full screen window is iconified, the original video mode of its monitor
|
|
is restored until the user or application restores the window.
|
|
|
|
Iconified windows can be restored with @ref glfwRestoreWindow.
|
|
|
|
@code
|
|
glfwRestoreWindow(window);
|
|
@endcode
|
|
|
|
When a full screen window is restored, the desired video mode is restored to its
|
|
monitor as well.
|
|
|
|
If you wish to be notified when a window is iconified or restored, whether by
|
|
the user, system or your own code, set a iconify callback.
|
|
|
|
@code
|
|
glfwSetWindowIconifyCallback(window, window_iconify_callback);
|
|
@endcode
|
|
|
|
The callback function receives changes in the iconification state of the window.
|
|
|
|
@code
|
|
void window_iconify_callback(GLFWwindow* window, int iconified)
|
|
{
|
|
if (iconified)
|
|
{
|
|
// The window was iconified
|
|
}
|
|
else
|
|
{
|
|
// The window was restored
|
|
}
|
|
}
|
|
@endcode
|
|
|
|
You can also get the current iconification state with @ref glfwGetWindowAttrib.
|
|
|
|
@code
|
|
int iconified = glfwGetWindowAttrib(window, GLFW_ICONIFIED);
|
|
@endcode
|
|
|
|
|
|
@subsection window_hide Window visibility
|
|
|
|
Windowed mode windows can be hidden with @ref glfwHideWindow.
|
|
|
|
@code
|
|
glfwHideWindow(window);
|
|
@endcode
|
|
|
|
This makes the window completely invisible to the user, including removing it
|
|
from the task bar, dock or window list. Full screen windows cannot be hidden
|
|
and calling @ref glfwHideWindow on a full screen window does nothing.
|
|
|
|
Hidden windows can be shown with @ref glfwShowWindow.
|
|
|
|
@code
|
|
glfwShowWindow(window);
|
|
@endcode
|
|
|
|
Windowed mode windows can be created initially hidden with the `GLFW_VISIBLE`
|
|
[window hint](@ref window_hints_wnd). Windows created hidden are completely
|
|
invisible to the user until shown. This can be useful if you need to set up
|
|
your window further before showing it, for example moving it to a specific
|
|
location.
|
|
|
|
You can also get the current visibility state with @ref glfwGetWindowAttrib.
|
|
|
|
@code
|
|
int visible = glfwGetWindowAttrib(window, GLFW_VISIBLE);
|
|
@endcode
|
|
|
|
|
|
@subsection window_focus Window input focus
|
|
|
|
If you wish to be notified when a window gains or loses input focus, whether by
|
|
the user, system or your own code, set a focus callback.
|
|
|
|
@code
|
|
glfwSetWindowFocusCallback(window, window_focus_callback);
|
|
@endcode
|
|
|
|
The callback function receives changes in the input focus state of the window.
|
|
|
|
@code
|
|
void window_focus_callback(GLFWwindow* window, int focused)
|
|
{
|
|
if (focused)
|
|
{
|
|
// The window gained input focus
|
|
}
|
|
else
|
|
{
|
|
// The window lost input focus
|
|
}
|
|
}
|
|
@endcode
|
|
|
|
You can also get the current input focus state with @ref glfwGetWindowAttrib.
|
|
|
|
@code
|
|
int focused = glfwGetWindowAttrib(window, GLFW_FOCUSED);
|
|
@endcode
|
|
|
|
|
|
@subsection window_refresh Window damage and refresh
|
|
|
|
If you wish to be notified when the contents of a window is damaged and needs
|
|
to be refreshed, set a window refresh callback.
|
|
|
|
@code
|
|
glfwSetWindowRefreshCallback(m_handle, window_refresh_callback);
|
|
@endcode
|
|
|
|
The callback function is called when the contents of the window needs to be
|
|
refreshed.
|
|
|
|
@code
|
|
void window_refresh_callback(GLFWwindow* window)
|
|
{
|
|
draw_editor_ui(window);
|
|
glfwSwapBuffers(window);
|
|
}
|
|
@endcode
|
|
|
|
@note On compositing window systems such as Aero, Compiz or Aqua, where the
|
|
window contents are saved off-screen, this callback might only be called when
|
|
the window or framebuffer is resized.
|
|
|
|
|
|
@subsection window_attribs Window attributes
|
|
|
|
Windows have a number of attributes that can be returned using @ref
|
|
glfwGetWindowAttrib. Some reflect state that may change during the lifetime of
|
|
the window, while others reflect the corresponding hints and are fixed at the
|
|
time of creation. Some are related to the actual window and others to its
|
|
context.
|
|
|
|
@code
|
|
if (glfwGetWindowAttrib(window, GLFW_FOCUSED))
|
|
{
|
|
// window has input focus
|
|
}
|
|
@endcode
|
|
|
|
|
|
@subsubsection window_attribs_wnd Window related attributes
|
|
|
|
`GLFW_FOCUSED` indicates whether the specified window has input focus. Initial
|
|
input focus is controlled by the [window hint](@ref window_hints_wnd) with the
|
|
same name.
|
|
|
|
`GLFW_ICONIFIED` indicates whether the specified window is iconified, whether by
|
|
the user or with @ref glfwIconifyWindow.
|
|
|
|
`GLFW_VISIBLE` indicates whether the specified window is visible. Window
|
|
visibility can be controlled with @ref glfwShowWindow and @ref glfwHideWindow
|
|
and initial visibility is controlled by the [window hint](@ref window_hints_wnd)
|
|
with the same name.
|
|
|
|
`GLFW_RESIZABLE` indicates whether the specified window is resizable _by the
|
|
user_. This is set on creation with the [window hint](@ref window_hints_wnd)
|
|
with the same name.
|
|
|
|
`GLFW_DECORATED` indicates whether the specified window has decorations such as
|
|
a border, a close widget, etc. This is set on creation with the
|
|
[window hint](@ref window_hints_wnd) with the same name.
|
|
|
|
`GLFW_FLOATING` indicates whether the specified window is floating, also called
|
|
topmost or always-on-top. This is controlled by the
|
|
[window hint](@ref window_hints_wnd) with the same name.
|
|
|
|
|
|
@subsubsection window_attribs_ctx Context related attributes
|
|
|
|
`GLFW_CLIENT_API` indicates the client API provided by the window's context;
|
|
either `GLFW_OPENGL_API`, `GLFW_OPENGL_ES_API` or `GLFW_NO_API`.
|
|
|
|
`GLFW_CONTEXT_VERSION_MAJOR`, `GLFW_CONTEXT_VERSION_MINOR` and
|
|
`GLFW_CONTEXT_REVISION` indicate the client API version of the window's context.
|
|
|
|
`GLFW_OPENGL_FORWARD_COMPAT` is `GLFW_TRUE` if the window's context is an OpenGL
|
|
forward-compatible one, or `GLFW_FALSE` otherwise.
|
|
|
|
`GLFW_OPENGL_DEBUG_CONTEXT` is `GLFW_TRUE` if the window's context is an OpenGL
|
|
debug context, or `GLFW_FALSE` otherwise.
|
|
|
|
`GLFW_OPENGL_PROFILE` indicates the OpenGL profile used by the context. This is
|
|
`GLFW_OPENGL_CORE_PROFILE` or `GLFW_OPENGL_COMPAT_PROFILE` if the context uses
|
|
a known profile, or `GLFW_OPENGL_ANY_PROFILE` if the OpenGL profile is unknown
|
|
or the context is an OpenGL ES context. Note that the returned profile may not
|
|
match the profile bits of the context flags, as GLFW will try other means of
|
|
detecting the profile when no bits are set.
|
|
|
|
`GLFW_CONTEXT_ROBUSTNESS` indicates the robustness strategy used by the context.
|
|
This is `GLFW_LOSE_CONTEXT_ON_RESET` or `GLFW_NO_RESET_NOTIFICATION` if the
|
|
window's context supports robustness, or `GLFW_NO_ROBUSTNESS` otherwise.
|
|
|
|
|
|
@subsubsection window_attribs_fb Framebuffer related attributes
|
|
|
|
The attributes of the default framebuffer (i.e. the framebuffer attached to the
|
|
window) are not provided by this function but can be queried with both OpenGL
|
|
and OpenGL ES.
|
|
|
|
If you are using version 3.0 or later of OpenGL or OpenGL ES, the
|
|
`glGetFramebufferAttachmentParameteriv` function can be used to retrieve the
|
|
number of bits for the red, green, blue, alpha, depth and stencil buffer
|
|
channels. Otherwise, the `glGetIntegerv` function can be used.
|
|
|
|
The number of MSAA samples are always retrieved with `glGetIntegerv`. For
|
|
contexts supporting framebuffer objects, the number of samples of the currently
|
|
bound framebuffer is returned.
|
|
|
|
Attribute | glGetIntegerv | glGetFramebufferAttachmentParameteriv
|
|
------------ | ----------------- | -------------------------------------
|
|
Red bits | `GL_RED_BITS` | `GL_FRAMEBUFFER_ATTACHMENT_RED_SIZE`
|
|
Green bits | `GL_GREEN_BITS` | `GL_FRAMEBUFFER_ATTACHMENT_GREEN_SIZE`
|
|
Blue bits | `GL_BLUE_BITS` | `GL_FRAMEBUFFER_ATTACHMENT_BLUE_SIZE`
|
|
Alpha bits | `GL_ALPHA_BITS` | `GL_FRAMEBUFFER_ATTACHMENT_ALPHA_SIZE`
|
|
Depth bits | `GL_DEPTH_BITS` | `GL_FRAMEBUFFER_ATTACHMENT_DEPTH_SIZE`
|
|
Stencil bits | `GL_STENCIL_BITS` | `GL_FRAMEBUFFER_ATTACHMENT_STENCIL_SIZE`
|
|
MSAA samples | `GL_SAMPLES` | _Not provided by this function_
|
|
|
|
When calling `glGetFramebufferAttachmentParameteriv`, the red, green, blue and
|
|
alpha sizes can be queried from the `GL_BACK_LEFT`, while the depth and stencil
|
|
sizes can be queried from the `GL_DEPTH` and `GL_STENCIL` attachments,
|
|
respectively.
|
|
|
|
|
|
@section buffer_swap Buffer swapping
|
|
|
|
GLFW windows are by default double buffered. That means that you have two
|
|
rendering buffers; a front buffer and a back buffer. The front buffer is
|
|
the one being displayed and the back buffer the one you render to.
|
|
|
|
When the entire frame has been rendered, it is time to swap the back and the
|
|
front buffers in order to display what has been rendered and begin rendering
|
|
a new frame. This is done with @ref glfwSwapBuffers.
|
|
|
|
@code
|
|
glfwSwapBuffers(window);
|
|
@endcode
|
|
|
|
Sometimes it can be useful to select when the buffer swap will occur. With the
|
|
function @ref glfwSwapInterval it is possible to select the minimum number of
|
|
monitor refreshes the driver wait should from the time @ref glfwSwapBuffers was
|
|
called before swapping the buffers:
|
|
|
|
@code
|
|
glfwSwapInterval(1);
|
|
@endcode
|
|
|
|
If the interval is zero, the swap will take place immediately when @ref
|
|
glfwSwapBuffers is called without waiting for a refresh. Otherwise at least
|
|
interval retraces will pass between each buffer swap. Using a swap interval of
|
|
zero can be useful for benchmarking purposes, when it is not desirable to
|
|
measure the time it takes to wait for the vertical retrace. However, a swap
|
|
interval of one lets you avoid tearing.
|
|
|
|
Note that this may not work on all machines, as some drivers have
|
|
user-controlled settings that override any swap interval the application
|
|
requests.
|
|
|
|
*/
|