RobustToolbox/Robust.Client/UserInterface/Tooltips.cs

using System;
using System.Numerics;
using Robust.Client.UserInterface.Controls;
using Robust.Shared.Maths;

namespace Robust.Client.UserInterface
{
    /// <summary>
    /// Utilities for working with tooltips.
    /// </summary>
    public static class Tooltips
    {

        /// <summary>
        /// Positions the provided control as a tooltip within the bounds of its parent UserInterfaceManager screen
        /// under the current mouse position. Sizing Based on its current combined minimum size.
        /// Defaults to the top left corner
        /// of the control being placed at the mouse position but
        /// adjusting to a different corner if the control would go beyond the edge of the bounds.
        /// </summary>
        /// <param name="tooltip">control to position (current size will be used to determine bounds)</param>
        public static void PositionTooltip(Control tooltip)
        {
            PositionTooltip(tooltip.Root!.Size,
                tooltip.UserInterfaceManager.MousePositionScaled.Position,
                tooltip);
        }

        /// <summary>
        /// Positions the provided control as a tooltip within the provided screenBounds based on its current
        /// combined minimum size.
        /// Defaults to the top left corner
        /// of the control being placed at the indicated position but
        /// adjusting to a different corner if the control would go beyond the edge of the bounds.
        /// </summary>
        /// <param name="screenBounds">max x and y screen coordinates for the tooltip to occupy, tooltip
        /// will be shifted to avoid exceeding these bounds.</param>
        /// <param name="screenPosition">position to place the tooltip at, in screen coordinates</param>
        /// <param name="tooltip">control to position (current size will be used to determine bounds)</param>
        public static void PositionTooltip(Vector2 screenBounds, Vector2 screenPosition, Control tooltip)
        {
            tooltip.Measure(Vector2Helpers.Infinity);
            var combinedMinSize = tooltip.DesiredSize;

            // If it overflows right bounds then just place left on the edge.
            var right = MathF.Min(screenPosition.X + combinedMinSize.X, screenBounds.X);

            // However, better to clamp the end of the tooltip instead of the start.
            var left = MathF.Max(0f, right - combinedMinSize.X);

            var bottom = MathF.Min(screenPosition.Y, screenBounds.Y);
            var top = MathF.Max(0f, bottom - combinedMinSize.Y);

            LayoutContainer.SetPosition(tooltip, new Vector2(left, top));
        }
    }
}