Detection of water by texture. Online Maps. Atlas of Examples

Tags:

Math

Detect the location on the water or on the land by additional texture.

Usage instructions:
Link to additional Texture
Add this script to map GameObject, select additional texture and start the scene.
Important: Make sure «Read / Write Enabled - ON» in Texture Importer.
Move your mouse over the map and click "P" to check whether there is water at the point under the cursor.
The result will be shown in the console.

DetectWaterByTextureExample.cs

/*         INFINITY CODE         */
/*   https://infinity-code.com   */

using OnlineMaps;
using UnityEngine;

namespace OnlineMapsExamples
{
    /// <summary>
    /// Example of detection of water by texture.
    /// This example requires a texture:
    /// https://infinity-code.com/atlas/online-maps/images/mapForDetectWaterBW4.jpg
    /// </summary>
    [AddComponentMenu(Utils.ExampleMenuPath + "DetectWaterByTextureExample")]
    public class DetectWaterByTextureExample : MonoBehaviour
    {
        /// <summary>
        /// Reference to the map. If not specified, the current instance will be used.
        /// </summary>
        public Map map;
        
        /// <summary>
        /// Color of water on the texture.
        /// </summary>
        public Color32 waterColor = Color.black;

        // Set map 2048x2048, with Read / Write Enabled
        public Texture2D mapForDetectWater;

        private void Start()
        {
            // If map is not specified, use the current instance.
            if (!map && !(map = Map.instance))
            {
                Debug.LogError("Map not found");
            }
        }

        private void Update()
        {
            // Check if the P key is released
            if (!InputManager.GetKeyUp(KeyCode.P)) return;
            
            // Get the coordinates under the cursor.
            GeoPoint cursorLocation = map.control.ScreenToLocation();
                
            // Check if there is water at this point
            bool hasWater = HasWater(cursorLocation);
            Debug.Log(hasWater ? "Has Water" : "No Water");
        }

        private bool HasWater(GeoPoint location)
        {
            // Convert geo coordinates to tile coordinates
            MercatorPoint mercatorPoint = location.ToMercator(map);

            // Check pixel color
            Color color = mapForDetectWater.GetPixelBilinear((float)mercatorPoint.x, (float)(1 - mercatorPoint.y));
            Debug.Log(mercatorPoint.x + "   " + mercatorPoint.y);

            return color == waterColor;
        }
    }
}