Question

我有Qt 5.3在DirectFB 1.7.4之上运行（以及qdirectfbintegration的一个小补丁，因为没有实现platformNativeInterface）。

我以3840x2160分辨率出现，然后使用下面的代码更改为1920x1080分辨率。分辨率发生变化，我可以确认查看fbset输出。我看到的问题是，在将分辨率更改为1920x1080后，Qt仍将其报告为3840x2160。

有谁知道如何强制Qt重新检查/更新它报告的分辨率？或者directfb插件中可能缺少什么来通知Qt引擎盖下发生了什么变化？

感谢。

IDirectFB * dfb = (IDirectFB*)m_app->platformNativeInterface();
if(dfb){
    std::cerr << "######## New resolution is " << width << "x" << height << std::endl;

    IDirectFBDisplayLayer *layer;
    DFBDisplayLayerConfig config;

    std::cerr << "######## Getting primary IDirectFBDisplayLayer" << std::endl;
    /* Get an interface to the primary layer. */
    dfb->GetDisplayLayer(dfb, DLID_PRIMARY, &layer);
    if(layer){
        DFBResult dres;
        std::cerr << "######## Got the primary display layer, setting admin" << std::endl;
        // This level allows window stack mode switches
        dres = layer->SetCooperativeLevel(layer, DLSCL_ADMINISTRATIVE);
        if(dres != DFB_OK){
            std::cerr << "######## Error: " << DirectFBErrorString(dres) << std::endl;
        }

        std::cerr << "######## Getting layer configuration" << std::endl;
        // Get layer configuration
        dres = layer->GetConfiguration(layer, &config);
        if(dres != DFB_OK){
            std::cerr << "######## Error: " << DirectFBErrorString(dres) << std::endl;
        }
        // Set the new resolution
        std::cerr << "######## Setting layer resolution" << std::endl;
        config.width = width;
        config.height = height;
        dres = layer->SetConfiguration(layer, &config);
        if(dres != DFB_OK){
            std::cerr << "######## Error: " << DirectFBErrorString(dres) << std::endl;
        }
    }

    // Print out resolution from Qt
    QRect res = QApplication::desktop()->screenGeometry();
    std::cerr << "######## QApplication resolution is now " << res.width() << "x" << res.height() << std::endl;

我从控制台看到的输出是： ######## New resolution is 1920x1080 ######## Getting primary IDirectFBDisplayLayer ######## Got the primary display layer, setting admin ######## Getting layer configuration ######## Setting layer resolution (*) FBDev/Mode: Setting 1920x1080 ARGB (*) FBDev/Mode: Switched to 1920x1080 (virtual 1920x2160) at 32 bit (ARGB), pitch 7680 ######## QApplication resolution is now 3840x2160 root@output:~# fbset mode "1920x1080-24" # D: 74.250 MHz, H: 27.000 kHz, V: 24.000 Hz geometry 1920 1080 1920 2160 32 timings 13468 148 638 36 4 44 5 accel false rgba 8/16,8/8,8/0,8/24 endmode

Answer 1

directfb qpa插件缺少几个功能。我正在处理插件的一些更新，我会在提交时发布一个链接。

对于临时解决方法：

WindowSystemInterface::handleScreenGeometryChange(m_app->screens().first(), QRect(0,0,width,height));

正在努力更新Qt中的分辨率。

QDesktopWidget :: screenGeometry返回不正确的值

1 个答案: