Cannot select from multiple available GPUs used by QQuickWindow.

ShenC

There are no appropriate functions that can set the GPU used by QQuickWindow/QQuickView.

I'm using qt6.3 on windows11. I get two GPUs on my laptop:

Device name: AMD Radeon(TM) Graphics
Device type: 1
Device name: NVIDIA GeForce RTX 3060 Laptop GPU
Device type: 2

I'm trying to use the vulkan api to render the qml scene. But I cannot set the GPU I want to use before showing a QQuickWindow object. One of the related functions is QQuickWindow::setGraphicsDevice, which is not feasible since it takes an already existing VkPhysicalDevice object. A VkPhysicalDevice object can only be created after showing a QQuickWindow object.

Meanwhile the widget class QVulkanWindow gives us a convenient function QVulkanWindow::setPhysicalDeviceIndex for doing this.

Perhaps the setting up with class QQuickRenderControl is possible for doing this, but there are too much stuff to take care of for merely selecting a GPU device. I thought it should be a common demand literally.

ShenC

Should I post this somewhere like feature request page, or there is an another solution for selecting from GPUs?

GrecKo

I would post this in https://lists.qt-project.org/listinfo/interest if I were you.