Method NavUpdateWindowing

KBotExt/imgui/imgui.cpp:12059–12246

Windowing management mode Keyboard: CTRL+Tab (change focus/move/resize), Alt (toggle menu layer) Gamepad: Hold Menu/Square (change focus/move/resize), Tap Menu/Square (toggle menu layer)

// Keyboard: CTRL+Tab (change focus/move/resize), Alt (toggle menu layer)
// Gamepad:  Hold Menu/Square (change focus/move/resize), Tap Menu/Square (toggle menu layer)
static void ImGui::NavUpdateWindowing()
{
	ImGuiContext& g = *GImGui;
	ImGuiIO& io = g.IO;

	ImGuiWindow* apply_focus_window = NULL;
	bool apply_toggle_layer = false;

	ImGuiWindow* modal_window = GetTopMostPopupModal();
	bool allow_windowing = (modal_window == NULL); // FIXME: This prevent CTRL+TAB from being usable with windows that are inside the Begin-stack of that modal.
	if (!allow_windowing)
		g.NavWindowingTarget = NULL;

	// Fade out
	if (g.NavWindowingTargetAnim && g.NavWindowingTarget == NULL)
	{
		g.NavWindowingHighlightAlpha = ImMax(g.NavWindowingHighlightAlpha - io.DeltaTime * 10.0f, 0.0f);
		if (g.DimBgRatio <= 0.0f && g.NavWindowingHighlightAlpha <= 0.0f)
			g.NavWindowingTargetAnim = NULL;
	}

	// Start CTRL+Tab or Square+L/R window selection
	const ImGuiID owner_id = ImHashStr("###NavUpdateWindowing");
	const bool nav_gamepad_active = (io.ConfigFlags & ImGuiConfigFlags_NavEnableGamepad) != 0 && (io.BackendFlags & ImGuiBackendFlags_HasGamepad) != 0;
	const bool nav_keyboard_active = (io.ConfigFlags & ImGuiConfigFlags_NavEnableKeyboard) != 0;
	const bool keyboard_next_window = allow_windowing && g.ConfigNavWindowingKeyNext && Shortcut(g.ConfigNavWindowingKeyNext, owner_id, ImGuiInputFlags_Repeat | ImGuiInputFlags_RouteAlways);
	const bool keyboard_prev_window = allow_windowing && g.ConfigNavWindowingKeyPrev && Shortcut(g.ConfigNavWindowingKeyPrev, owner_id, ImGuiInputFlags_Repeat | ImGuiInputFlags_RouteAlways);
	const bool start_windowing_with_gamepad = allow_windowing && nav_gamepad_active && !g.NavWindowingTarget && IsKeyPressed(ImGuiKey_NavGamepadMenu, 0, ImGuiInputFlags_None);
	const bool start_windowing_with_keyboard = allow_windowing && !g.NavWindowingTarget && (keyboard_next_window || keyboard_prev_window); // Note: enabled even without NavEnableKeyboard!
	if (start_windowing_with_gamepad || start_windowing_with_keyboard)
		if (ImGuiWindow* window = g.NavWindow ? g.NavWindow : FindWindowNavFocusable(g.WindowsFocusOrder.Size - 1, -INT_MAX, -1))
		{
			g.NavWindowingTarget = g.NavWindowingTargetAnim = window->RootWindow;
			g.NavWindowingTimer = g.NavWindowingHighlightAlpha = 0.0f;
			g.NavWindowingAccumDeltaPos = g.NavWindowingAccumDeltaSize = ImVec2(0.0f, 0.0f);
			g.NavWindowingToggleLayer = start_windowing_with_gamepad ? true : false; // Gamepad starts toggling layer
			g.NavInputSource = start_windowing_with_keyboard ? ImGuiInputSource_Keyboard : ImGuiInputSource_Gamepad;

			// Register ownership of our mods. Using ImGuiInputFlags_RouteGlobalHigh in the Shortcut() calls instead would probably be correct but may have more side-effects.
			if (keyboard_next_window || keyboard_prev_window)
				SetKeyOwnersForKeyChord((g.ConfigNavWindowingKeyNext | g.ConfigNavWindowingKeyPrev) & ImGuiMod_Mask_, owner_id);
		}

	// Gamepad update
	g.NavWindowingTimer += io.DeltaTime;
	if (g.NavWindowingTarget && g.NavInputSource == ImGuiInputSource_Gamepad)
	{
		// Highlight only appears after a brief time holding the button, so that a fast tap on PadMenu (to toggle NavLayer) doesn't add visual noise
		g.NavWindowingHighlightAlpha = ImMax(g.NavWindowingHighlightAlpha, ImSaturate((g.NavWindowingTimer - NAV_WINDOWING_HIGHLIGHT_DELAY) / 0.05f));

		// Select window to focus
		const int focus_change_dir = (int)IsKeyPressed(ImGuiKey_GamepadL1) - (int)IsKeyPressed(ImGuiKey_GamepadR1);
		if (focus_change_dir != 0)
		{
			NavUpdateWindowingHighlightWindow(focus_change_dir);
			g.NavWindowingHighlightAlpha = 1.0f;
		}