Method UpdateWindowManualResize

KBotExt/imgui/imgui.cpp:5791–5934

Handle resize for: Resize Grips, Borders, Gamepad Return true when using auto-fit (double-click on resize grip)

// Handle resize for: Resize Grips, Borders, Gamepad
// Return true when using auto-fit (double-click on resize grip)
static bool ImGui::UpdateWindowManualResize(ImGuiWindow* window, const ImVec2& size_auto_fit, int* border_held, int resize_grip_count, ImU32 resize_grip_col[4], const ImRect& visibility_rect)
{
	ImGuiContext& g = *GImGui;
	ImGuiWindowFlags flags = window->Flags;

	if ((flags & ImGuiWindowFlags_NoResize) || (flags & ImGuiWindowFlags_AlwaysAutoResize) || window->AutoFitFramesX > 0 || window->AutoFitFramesY > 0)
		return false;
	if (window->WasActive == false) // Early out to avoid running this code for e.g. a hidden implicit/fallback Debug window.
		return false;

	bool ret_auto_fit = false;
	const int resize_border_count = g.IO.ConfigWindowsResizeFromEdges ? 4 : 0;
	const float grip_draw_size = IM_FLOOR(ImMax(g.FontSize * 1.35f, window->WindowRounding + 1.0f + g.FontSize * 0.2f));
	const float grip_hover_inner_size = IM_FLOOR(grip_draw_size * 0.75f);
	const float grip_hover_outer_size = g.IO.ConfigWindowsResizeFromEdges ? WINDOWS_HOVER_PADDING : 0.0f;

	ImRect clamp_rect = visibility_rect;
	const bool window_move_from_title_bar = g.IO.ConfigWindowsMoveFromTitleBarOnly && !(window->Flags & ImGuiWindowFlags_NoTitleBar);
	if (window_move_from_title_bar)
		clamp_rect.Min.y -= window->TitleBarHeight();

	ImVec2 pos_target(FLT_MAX, FLT_MAX);
	ImVec2 size_target(FLT_MAX, FLT_MAX);

	// Resize grips and borders are on layer 1
	window->DC.NavLayerCurrent = ImGuiNavLayer_Menu;

	// Manual resize grips
	PushID("#RESIZE");
	for (int resize_grip_n = 0; resize_grip_n < resize_grip_count; resize_grip_n++)
	{
		const ImGuiResizeGripDef& def = resize_grip_def[resize_grip_n];
		const ImVec2 corner = ImLerp(window->Pos, window->Pos + window->Size, def.CornerPosN);

		// Using the FlattenChilds button flag we make the resize button accessible even if we are hovering over a child window
		bool hovered, held;
		ImRect resize_rect(corner - def.InnerDir * grip_hover_outer_size, corner + def.InnerDir * grip_hover_inner_size);
		if (resize_rect.Min.x > resize_rect.Max.x) ImSwap(resize_rect.Min.x, resize_rect.Max.x);
		if (resize_rect.Min.y > resize_rect.Max.y) ImSwap(resize_rect.Min.y, resize_rect.Max.y);
		ImGuiID resize_grip_id = window->GetID(resize_grip_n); // == GetWindowResizeCornerID()
		ItemAdd(resize_rect, resize_grip_id, NULL, ImGuiItemFlags_NoNav);
		ButtonBehavior(resize_rect, resize_grip_id, &hovered, &held, ImGuiButtonFlags_FlattenChildren | ImGuiButtonFlags_NoNavFocus);
		//GetForegroundDrawList(window)->AddRect(resize_rect.Min, resize_rect.Max, IM_COL32(255, 255, 0, 255));
		if (hovered || held)
			g.MouseCursor = (resize_grip_n & 1) ? ImGuiMouseCursor_ResizeNESW : ImGuiMouseCursor_ResizeNWSE;

		if (held && g.IO.MouseClickedCount[0] == 2 && resize_grip_n == 0)
		{
			// Manual auto-fit when double-clicking
			size_target = CalcWindowSizeAfterConstraint(window, size_auto_fit);
			ret_auto_fit = true;
			ClearActiveID();
		}
		else if (held)
		{
			// Resize from any of the four corners
			// We don't use an incremental MouseDelta but rather compute an absolute target size based on mouse position
			ImVec2 clamp_min = ImVec2(def.CornerPosN.x == 1.0f ? clamp_rect.Min.x : -FLT_MAX, (def.CornerPosN.y == 1.0f || (def.CornerPosN.y == 0.0f && window_move_from_title_bar)) ? clamp_rect.Min.y : -FLT_MAX);