Unity-DebugX/Runtime/Gizmos/DebugX.text.cs

using DCFApixels.DebugXCore;
#if UNITY_EDITOR
using UnityEditor;
#endif
using UnityEngine;
using UnityEngine.Rendering;

namespace DCFApixels
{
    using IN = System.Runtime.CompilerServices.MethodImplAttribute;

    public static partial class DebugX
    {
        public readonly partial struct DrawHandler
        {
            #region Text
            [IN(LINE)] public DrawHandler TextWorldScale(Vector3 position, object text) => Gizmo(new TextGizmo(position, text, DebugXTextSettings.Default, true));
            [IN(LINE)] public DrawHandler TextWorldScale(Vector3 position, object text, DebugXTextSettings settings) => Gizmo(new TextGizmo(position, text, settings, true));
            [IN(LINE)] public DrawHandler Text(Vector3 position, object text) => Gizmo(new TextGizmo(position, text, DebugXTextSettings.Default, false));
            [IN(LINE)] public DrawHandler Text(Vector3 position, object text, DebugXTextSettings settings) => Gizmo(new TextGizmo(position, text, settings, false));

            private readonly struct TextGizmo : IGizmo<TextGizmo>
            {
                public readonly Vector3 Position;
                public readonly string Text;
                public readonly DebugXTextSettings Settings;
                public readonly bool IsWorldSpaceScale;
                [IN(LINE)]
                public TextGizmo(Vector3 position, object text, DebugXTextSettings settings, bool isWorldSpaceScale)
                {
                    Position = position;
                    Text = text.ToString();
                    Settings = settings;
                    IsWorldSpaceScale = isWorldSpaceScale;
                }

                public IGizmoRenderer<TextGizmo> RegisterNewRenderer() { return new Renderer(); }

                #region Renderer
                private class Renderer : IGizmoRenderer<TextGizmo>
                {
                    private static GUIStyle _labelStyle; 
                    private static GUIContent _labelDummy;
                    private static Texture2D _whiteTexture;
                    public int ExecuteOrder => default(UnlitMat).GetExecuteOrder();
                    public bool IsStaticRender => false;
                    public void Prepare(Camera camera, GizmosList<TextGizmo> list) { }
                    public void Render(Camera camera, GizmosList<TextGizmo> list, CommandBuffer cb)
                    {
                        Render_UnityGizmos(camera, list);
                    }
                    public void Render_UnityGizmos(Camera camera, GizmosList<TextGizmo> list)
                    {
                        if (Event.current.type != EventType.Repaint) { return; }
                        Color dfColor = GUI.color;

                        if (camera == null) { return; }
                        InitStatic();
                        var zoom = GetCameraZoom(camera);
                        var isSceneView = camera.name == "SceneCamera";
                        //Handles.BeginGUI();
                        foreach (ref readonly var item in list)
                        {
                            _labelDummy.text = item.Value.Text;
                            GUIStyle style = _labelStyle;

                            style.fontSize = item.Value.IsWorldSpaceScale
                                ? Mathf.FloorToInt(item.Value.Settings.FontSize / zoom)
                                : item.Value.Settings.FontSize;

                            style.alignment = item.Value.Settings.TextAnchor;
                            if (!(WorldToGUIPointWithDepth(camera, item.Value.Position).z < 0f))
                            {
                                Rect rect = WorldPointToSizedRect(camera, item.Value.Position, _labelDummy, _labelStyle);

                                GL.PushMatrix();
                                GL.LoadPixelMatrix(0, Screen.width, Screen.height - (isSceneView ? 50 : 0), 0);


                                Color c = item.Value.Settings.BackgroundColor * GlobalColor;
                                GUI.color = c;
                                var mat = DebugXAssets.Materials.Unlit;
                                mat.SetColor(ColorPropertyID, c);
                                Graphics.DrawTexture(rect, _whiteTexture, mat);

                                GUI.color = item.Color * GlobalColor;
                                style.Draw(rect, _labelDummy, false, false, false, false);


                                GL.PopMatrix();
                            }
                        }
                        GUI.color = dfColor;
                        DebugXAssets.Materials.Unlit.SetColor(ColorPropertyID, Color.white);
                    }


                    #region Utils
                    public static Vector3 WorldToGUIPointWithDepth(Camera camera, Vector3 world)
                    {
#if UNITY_EDITOR
                        world = Handles.matrix.MultiplyPoint(world);
#endif
                        Vector3 vector = camera.WorldToScreenPoint(world);
                        vector.y = camera.pixelHeight - vector.y;
                        Vector2 vector2 = (Vector2)(vector);
#if UNITY_EDITOR
                        vector2 = EditorGUIUtility.PixelsToPoints(vector);
#endif
                        return new Vector3(vector2.x, vector2.y, vector.z);
                    }
                    public static Rect WorldPointToSizedRect(Camera camera, Vector3 position, GUIContent content, GUIStyle style)
                    {
                        Vector2 vector = (Vector2)WorldToGUIPointWithDepth(camera, position);
                        Vector2 vector2 = style.CalcSize(content);
                        Rect rect = new Rect(vector.x, vector.y, vector2.x, vector2.y);
                        switch (style.alignment)
                        {
                            case TextAnchor.UpperCenter:
                                rect.x -= rect.width * 0.5f;
                                break;
                            case TextAnchor.UpperRight:
                                rect.x -= rect.width;
                                break;
                            case TextAnchor.MiddleLeft:
                                rect.y -= rect.height * 0.5f;
                                break;
                            case TextAnchor.MiddleCenter:
                                rect.x -= rect.width * 0.5f;
                                rect.y -= rect.height * 0.5f;
                                break;
                            case TextAnchor.MiddleRight:
                                rect.x -= rect.width;
                                rect.y -= rect.height * 0.5f;
                                break;
                            case TextAnchor.LowerLeft:
                                rect.y -= rect.height;
                                break;
                            case TextAnchor.LowerCenter:
                                rect.x -= rect.width * 0.5f;
                                rect.y -= rect.height;
                                break;
                            case TextAnchor.LowerRight:
                                rect.x -= rect.width;
                                rect.y -= rect.height;
                                break;
                        }
                        return style.padding.Add(rect);
                    }
                    #endregion


                    private void InitStatic()
                    {
                        if (_labelStyle == null || _labelDummy == null || _whiteTexture == null)
                        {
                            GUIStyleState GenerateGUIStyleState()
                            {
                                var result = new GUIStyleState();
                                result.textColor = Color.white;
                                result.background = null;
                                return result;
                            }
                            GUISkin skin = (GUISkin)typeof(GUI).GetField("s_Skin", System.Reflection.BindingFlags.NonPublic | System.Reflection.BindingFlags.Static).GetValue(null);  //GUI.s_Skin
                            //GUISkin skin = GUI.skin;
                            _labelStyle = new GUIStyle(skin.label)
                            {
                                richText = false,
                                padding = new RectOffset(1, 1, 1, 1),
                                margin = new RectOffset(0, 0, 0, 0),
                                normal = GenerateGUIStyleState(),
                                active = GenerateGUIStyleState(),
                                hover = GenerateGUIStyleState(),
                                focused = GenerateGUIStyleState(),
                            };

                            _labelDummy = new GUIContent();

                            _whiteTexture = new Texture2D(2, 2);
                            Color32[] color = new Color32[]
                            {
                                new Color32(255,255,255,255),
                                new Color32(255,255,255,255),
                                new Color32(255,255,255,255),
                                new Color32(255,255,255,255),
                            };
                            _whiteTexture.SetPixels32(color);
                            _whiteTexture.Apply();
                        }
                    }
                    private static float GetCameraZoom(Camera camera)
                    {
                        const float DEFAULT_ZOOM = 1f;

                        if (camera != null)
                        {
                            return camera.orthographicSize;
                        }
                        return DEFAULT_ZOOM;

                        //var currentDrawingSceneView = SceneView.currentDrawingSceneView;
                        //
                        //if (currentDrawingSceneView == null)
                        //{
                        //    return DEFAULT_ZOOM;
                        //}
                        //
                        //var localCamera = currentDrawingSceneView.camera;
                        //
                        //if (localCamera != null)
                        //{
                        //    return localCamera.orthographicSize;
                        //}
                        //
                        //return DEFAULT_ZOOM;
                    }
                }
                #endregion
            }

#endregion
        }
    }
}