glfw/src/x11_monitor.c

//========================================================================
// GLFW - An OpenGL library
// Platform:    X11 (Unix)
// API version: 3.0
// WWW:         http://www.glfw.org/
//------------------------------------------------------------------------
// Copyright (c) 2002-2006 Marcus Geelnard
// Copyright (c) 2006-2010 Camilla Berglund <elmindreda@elmindreda.org>
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
//    claim that you wrote the original software. If you use this software
//    in a product, an acknowledgment in the product documentation would
//    be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such, and must not
//    be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source
//    distribution.
//
//========================================================================

#include "internal.h"

#include <stdlib.h>
#include <string.h>


//========================================================================
// Create a monitor struct from the specified information
//========================================================================

#if defined (_GLFW_HAS_XRANDR)
static _GLFWmonitor** createMonitor(_GLFWmonitor** current,
                                    XRROutputInfo* outputInfo,
                                    XRRCrtcInfo* crtcInfo)
{
    *current = malloc(sizeof(_GLFWmonitor));
    memset(*current, 0, sizeof(_GLFWmonitor));

    (*current)->physicalWidth  = outputInfo->mm_width;
    (*current)->physicalHeight = outputInfo->mm_height;

    (*current)->name = strdup(outputInfo->name);

    (*current)->screenX = crtcInfo->x;
    (*current)->screenY = crtcInfo->y;

    (*current)->X11.output = outputInfo;
    return &((*current)->next);
}
#endif /*_GLFW_HAS_XRANDR*/


//////////////////////////////////////////////////////////////////////////
//////                       GLFW platform API                      //////
//////////////////////////////////////////////////////////////////////////

//========================================================================
// Destroy a monitor struct
//========================================================================

_GLFWmonitor* _glfwDestroyMonitor(_GLFWmonitor* monitor)
{
    _GLFWmonitor* result;

    result = monitor->next;

#if defined (_GLFW_HAS_XRANDR)
    XRRFreeOutputInfo(monitor->X11.output);
#endif /*_GLFW_HAS_XRANDR*/

    free(monitor->modes);
    free(monitor->name);
    free(monitor);

    return result;
}


//========================================================================
// Return a list of available monitors
//========================================================================

_GLFWmonitor* _glfwCreateMonitors(void)
{
    _GLFWmonitor* monitorList = NULL;

    if (_glfwLibrary.X11.RandR.available)
    {
#if defined (_GLFW_HAS_XRANDR)
        int oi;
        XRRScreenResources* resources;
        _GLFWmonitor** monitor = &monitorList;

        resources = XRRGetScreenResources(_glfwLibrary.X11.display,
                                          _glfwLibrary.X11.root);

        for (oi = 0;  oi < resources->noutput;  oi++)
        {
            // physical device
            XRROutputInfo* outputInfo = NULL;
            // logical surface
            XRRCrtcInfo* crtcInfo = NULL;

            outputInfo = XRRGetOutputInfo(_glfwLibrary.X11.display,
                                          resources,
                                          resources->outputs[oi]);

            if (outputInfo->connection == RR_Connected)
            {
                int ci;

                for (ci = 0;  ci < outputInfo->ncrtc;  ci++)
                {
                    if (outputInfo->crtc == outputInfo->crtcs[ci])
                    {
                        crtcInfo = XRRGetCrtcInfo(_glfwLibrary.X11.display,
                                                  resources,
                                                  outputInfo->crtcs[ci]);
                        break;
                    }
                }

                monitor = createMonitor(monitor, outputInfo, crtcInfo);

                // Freeing of the outputInfo is done in _glfwDestroyMonitor
                XRRFreeCrtcInfo(crtcInfo);
            }
        }
#endif /*_GLFW_HAS_XRANDR*/
    }

    return monitorList;
}