Method NewFrame

lib/imgui/imgui.cpp:3586–3803

}

void ImGui::NewFrame()
{
    IM_ASSERT(GImGui != NULL && "No current context. Did you call ImGui::CreateContext() and ImGui::SetCurrentContext() ?");
    ImGuiContext& g = *GImGui;

#ifdef IMGUI_ENABLE_TEST_ENGINE
    ImGuiTestEngineHook_PreNewFrame(&g);
#endif

    // Check and assert for various common IO and Configuration mistakes
    NewFrameSanityChecks();

    // Load settings on first frame (if not explicitly loaded manually before)
    if (!g.SettingsLoaded)
    {
        IM_ASSERT(g.SettingsWindows.empty());
        if (g.IO.IniFilename)
            LoadIniSettingsFromDisk(g.IO.IniFilename);
        g.SettingsLoaded = true;
    }

    // Save settings (with a delay after the last modification, so we don't spam disk too much)
    if (g.SettingsDirtyTimer > 0.0f)
    {
        g.SettingsDirtyTimer -= g.IO.DeltaTime;
        if (g.SettingsDirtyTimer <= 0.0f)
        {
            if (g.IO.IniFilename != NULL)
                SaveIniSettingsToDisk(g.IO.IniFilename);
            else
                g.IO.WantSaveIniSettings = true;  // Let user know they can call SaveIniSettingsToMemory(). user will need to clear io.WantSaveIniSettings themselves.
            g.SettingsDirtyTimer = 0.0f;
        }
    }

    g.Time += g.IO.DeltaTime;
    g.WithinFrameScope = true;
    g.FrameCount += 1;
    g.TooltipOverrideCount = 0;
    g.WindowsActiveCount = 0;

    // Setup current font and draw list shared data
    g.IO.Fonts->Locked = true;
    SetCurrentFont(GetDefaultFont());
    IM_ASSERT(g.Font->IsLoaded());
    g.DrawListSharedData.ClipRectFullscreen = ImVec4(0.0f, 0.0f, g.IO.DisplaySize.x, g.IO.DisplaySize.y);
    g.DrawListSharedData.CurveTessellationTol = g.Style.CurveTessellationTol;
    g.DrawListSharedData.SetCircleSegmentMaxError(g.Style.CircleSegmentMaxError);
    g.DrawListSharedData.InitialFlags = ImDrawListFlags_None;
    if (g.Style.AntiAliasedLines)
        g.DrawListSharedData.InitialFlags |= ImDrawListFlags_AntiAliasedLines;
    if (g.Style.AntiAliasedFill)
        g.DrawListSharedData.InitialFlags |= ImDrawListFlags_AntiAliasedFill;
    if (g.IO.BackendFlags & ImGuiBackendFlags_RendererHasVtxOffset)
        g.DrawListSharedData.InitialFlags |= ImDrawListFlags_AllowVtxOffset;

    g.BackgroundDrawList.Clear();
    g.BackgroundDrawList.PushTextureID(g.IO.Fonts->TexID);