Function prepare_windows

pub fn prepare_windows(
    windows: ResMut<'_, ExtractedWindows>,
    window_surfaces: ResMut<'_, WindowSurfaces>,
    render_device: Res<'_, RenderDevice>,
    render_adapter: Res<'_, RenderAdapter>,
    screenshot_pipeline: Res<'_, ScreenshotToScreenPipeline>,
    pipeline_cache: Res<'_, PipelineCache>,
    pipelines: ResMut<'_, SpecializedRenderPipelines<ScreenshotToScreenPipeline>>,
    msaa: ResMut<'_, Msaa>,
    render_instance: Res<'_, RenderInstance>,
)

(re)configures window surfaces, and obtains a swapchain texture for rendering.

NOTE: get_current_texture in prepare_windows can take a long time if the GPU workload is the performance bottleneck. This can be seen in profiles as multiple prepare-set systems all taking an unusually long time to complete, and all finishing at about the same time as the prepare_windows system. Improvements in bevy are planned to avoid this happening when it should not but it will still happen as it is easy for a user to create a large GPU workload relative to the GPU performance and/or CPU workload. This can be caused by many reasons, but several of them are:

• GPU workload is more than your current GPU can manage
• Error / performance bug in your custom shaders
• wgpu was unable to detect a proper GPU hardware-accelerated device given the chosen Backends, WgpuLimits, and/or WgpuFeatures. For example, on Windows currently DirectX 11 is not supported by wgpu 0.12 and so if your GPU/drivers do not support Vulkan, it may be that a software renderer called “Microsoft Basic Render Driver” using DirectX 12 will be chosen and performance will be very poor. This is visible in a log message that is output during renderer initialization. Future versions of wgpu will support DirectX 11, but another alternative is to try to use ANGLE and Backends::GL if your GPU/drivers support OpenGL 4.3 / OpenGL ES 3.0 or later.