// When IMGUI_UNLIMITED_FRAME_RATE is defined we render into latest image acquired from the swapchain but we display the image which was rendered before.
// When IMGUI_UNLIMITED_FRAME_RATE is defined we render into latest image acquired from the swapchain but we display the image which was rendered before.
// Hence we must render once and increase the g_FrameIndex without presenting, which we do before entering the render loop.
// Hence we must render once and increase the g_FrameIndex without presenting, which we do before entering the render loop.