RTS-stil enhedsvalg for Unity

I denne tutorial vil jeg vise, hvordan man opretter et RTS (Real-Time Strategy) boks-stil enhedsvalg i Unity.

Sharp Coder Videoafspiller

Så lad os begynde!

Trin 1: Opret de nødvendige scripts

Dette indlæg indeholder 2 scripts:

SC_Selectable.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class SC_Selectable : MonoBehaviour
{
    public Renderer[] renderers; //Assign all child Mesh Renderers

    public Bounds GetObjectBounds()
    {
        Bounds totalBounds = new Bounds();

        for(int i = 0; i < renderers.Length; i++)
        {
            if(totalBounds.center == Vector3.zero)
            {
                totalBounds = renderers[i].bounds;
            }
            else
            {
                totalBounds.Encapsulate(renderers[i].bounds);
            }
        }

        return totalBounds;
    }

    void OnEnable()
    {
        //Add this Object to global list
        if (!SC_SelectionManager.selectables.Contains(this))
        {
            SC_SelectionManager.selectables.Add(this);
        }
    }

    void OnDisable()
    {
        //Remove this Object from global list
        if (SC_SelectionManager.selectables.Contains(this))
        {
            SC_SelectionManager.selectables.Remove(this);
        }
    }
}

SC_SelectionManager.cs

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class SC_SelectionManager : MonoBehaviour
{
    public Texture topLeftBorder;
    public Texture bottomLeftBorder;
    public Texture topRightBorder;
    public Texture bottomRightBorder;

    Texture2D _borderTexture;
    Texture2D borderTexture
    {
        get
        {
            if (_borderTexture == null)
            {
                _borderTexture = new Texture2D(1, 1);
                _borderTexture.SetPixel(0, 0, Color.white);
                _borderTexture.Apply();
            }

            return _borderTexture;
        }
    }

    bool selectionStarted = false;
    Vector3 mousePosition1;

    public static List<SC_Selectable> selectables = new List<SC_Selectable>();
    List<int> selectedObjects = new List<int>();

    // Update is called once per frame
    void Update()
    {
        // Begin selection
        if (Input.GetMouseButtonDown(0))
        {
            selectionStarted = true;
            mousePosition1 = Input.mousePosition;
        }
        // End selection
        if (Input.GetMouseButtonUp(0))
        {
            selectionStarted = false;
        }

        if (selectionStarted)
        {
            // Detect which Objects are inside selection rectangle
            Camera camera = Camera.main;
            selectedObjects.Clear();
            for (int i = 0; i < selectables.Count; i++)
            {
                Bounds viewportBounds = GetViewportBounds(camera, mousePosition1, Input.mousePosition);
                if (viewportBounds.Contains(camera.WorldToViewportPoint(selectables[i].transform.position)))
                {
                    selectedObjects.Add(i);
                }
            }
        }
    }

    void OnGUI()
    {
        if (selectionStarted)
        {
            Rect rect = GetScreenRect(mousePosition1, Input.mousePosition);
            DrawScreenRectBorder(rect, 2, Color.cyan);
        }

        // Draw selection edges
        if(selectedObjects.Count > 0)
        {
            Camera camera = Camera.main;
            for (int i = 0; i < selectedObjects.Count; i++)
            {
                DrawSelectionIndicator(camera, selectables[selectedObjects[i]].GetObjectBounds());
            }
        }
    }

    void DrawScreenRectBorder(Rect rect, float thickness, Color color)
    {
        // Top
        DrawBorderRect(new Rect(rect.xMin, rect.yMin, rect.width, thickness), color);
        // Left
        DrawBorderRect(new Rect(rect.xMin, rect.yMin, thickness, rect.height), color);
        // Right
        DrawBorderRect(new Rect(rect.xMax - thickness, rect.yMin, thickness, rect.height), color);
        // Bottom
        DrawBorderRect(new Rect(rect.xMin, rect.yMax - thickness, rect.width, thickness), color);
    }

    void DrawBorderRect(Rect rect, Color color)
    {
        GUI.color = color;
        GUI.DrawTexture(rect, borderTexture);
        GUI.color = Color.white;
    }

    Rect GetScreenRect(Vector3 screenPosition1, Vector3 screenPosition2)
    {
        // Move origin from bottom left to top left
        screenPosition1.y = Screen.height - screenPosition1.y;
        screenPosition2.y = Screen.height - screenPosition2.y;
        // Calculate corners
        var topLeft = Vector3.Min(screenPosition1, screenPosition2);
        var bottomRight = Vector3.Max(screenPosition1, screenPosition2);
        // Create Rect
        return Rect.MinMaxRect(topLeft.x, topLeft.y, bottomRight.x, bottomRight.y);
    }

    Bounds GetViewportBounds(Camera camera, Vector3 screenPosition1, Vector3 screenPosition2)
    {
        Vector3 v1 = camera.ScreenToViewportPoint(screenPosition1);
        Vector3 v2 = camera.ScreenToViewportPoint(screenPosition2);
        Vector3 min = Vector3.Min(v1, v2);
        Vector3 max = Vector3.Max(v1, v2);
        min.z = camera.nearClipPlane;
        max.z = camera.farClipPlane;

        Bounds bounds = new Bounds();
        bounds.SetMinMax(min, max);
        return bounds;
    }

    void DrawSelectionIndicator(Camera camera, Bounds bounds)
    {
        Vector3 boundPoint1 = bounds.min;
        Vector3 boundPoint2 = bounds.max;
        Vector3 boundPoint3 = new Vector3(boundPoint1.x, boundPoint1.y, boundPoint2.z);
        Vector3 boundPoint4 = new Vector3(boundPoint1.x, boundPoint2.y, boundPoint1.z);
        Vector3 boundPoint5 = new Vector3(boundPoint2.x, boundPoint1.y, boundPoint1.z);
        Vector3 boundPoint6 = new Vector3(boundPoint1.x, boundPoint2.y, boundPoint2.z);
        Vector3 boundPoint7 = new Vector3(boundPoint2.x, boundPoint1.y, boundPoint2.z);
        Vector3 boundPoint8 = new Vector3(boundPoint2.x, boundPoint2.y, boundPoint1.z);

        Vector2[] screenPoints = new Vector2[8];
        screenPoints[0] = camera.WorldToScreenPoint(boundPoint1);
        screenPoints[1] = camera.WorldToScreenPoint(boundPoint2);
        screenPoints[2] = camera.WorldToScreenPoint(boundPoint3);
        screenPoints[3] = camera.WorldToScreenPoint(boundPoint4);
        screenPoints[4] = camera.WorldToScreenPoint(boundPoint5);
        screenPoints[5] = camera.WorldToScreenPoint(boundPoint6);
        screenPoints[6] = camera.WorldToScreenPoint(boundPoint7);
        screenPoints[7] = camera.WorldToScreenPoint(boundPoint8);

        Vector2 topLeftPosition = Vector2.zero;
        Vector2 topRightPosition = Vector2.zero;
        Vector2 bottomLeftPosition = Vector2.zero;
        Vector2 bottomRightPosition = Vector2.zero;

        for (int a = 0; a < screenPoints.Length; a++)
        {
            //Top Left
            if (topLeftPosition.x == 0 || topLeftPosition.x > screenPoints[a].x)
            {
                topLeftPosition.x = screenPoints[a].x;
            }
            if (topLeftPosition.y == 0 || topLeftPosition.y > Screen.height - screenPoints[a].y)
            {
                topLeftPosition.y = Screen.height - screenPoints[a].y;
            }
            //Top Right
            if (topRightPosition.x == 0 || topRightPosition.x < screenPoints[a].x)
            {
                topRightPosition.x = screenPoints[a].x;
            }
            if (topRightPosition.y == 0 || topRightPosition.y > Screen.height - screenPoints[a].y)
            {
                topRightPosition.y = Screen.height - screenPoints[a].y;
            }
            //Bottom Left
            if (bottomLeftPosition.x == 0 || bottomLeftPosition.x > screenPoints[a].x)
            {
                bottomLeftPosition.x = screenPoints[a].x;
            }
            if (bottomLeftPosition.y == 0 || bottomLeftPosition.y < Screen.height - screenPoints[a].y)
            {
                bottomLeftPosition.y = Screen.height - screenPoints[a].y;
            }
            //Bottom Right
            if (bottomRightPosition.x == 0 || bottomRightPosition.x < screenPoints[a].x)
            {
                bottomRightPosition.x = screenPoints[a].x;
            }
            if (bottomRightPosition.y == 0 || bottomRightPosition.y < Screen.height - screenPoints[a].y)
            {
                bottomRightPosition.y = Screen.height - screenPoints[a].y;
            }
        }

        GUI.DrawTexture(new Rect(topLeftPosition.x - 16, topLeftPosition.y - 16, 16, 16), topLeftBorder);
        GUI.DrawTexture(new Rect(topRightPosition.x, topRightPosition.y - 16, 16, 16), topRightBorder);
        GUI.DrawTexture(new Rect(bottomLeftPosition.x - 16, bottomLeftPosition.y, 16, 16), bottomLeftBorder);
        GUI.DrawTexture(new Rect(bottomRightPosition.x, bottomRightPosition.y, 16, 16), bottomRightBorder);
    }
}

Trin 2: Konfigurer RTS-valget

Opret et nyt spilobjekt og kald det "_SelectionManager"
Vedhæft SC_SelectionManager-scriptet til "_SelectionManager"-objektet
Tildel teksturer nedenfor til kantvariabler:

Træk og slip de objekter, du har til hensigt at vælge til scenen (i mit tilfælde brugte jeg modellerne fra RPG/FPS Game Assets for PC/Mobile Industrial Set v2.0-pakken fra Asset Store)

Vedhæft SC_Selectable script til hver model
Tildel Mesh Renderer (eller Mesh Renderers, hvis der er flere objekter) til Renderers array, dette er nødvendigt for at beregne objektgrænser.

Tryk nu på Play og hold museknappen nede for at begynde valget.

Hold markøren over de valgbare Objekter for at vælge dem.

unity3d unity gamedev tutorial klik træk vælg gui ongui udvælgelse værktøj script rts realtid strategi mål