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coryleachcoryleach
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Fixes to hex mesh gen
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3 files changed

+301
-148
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3 files changed

+301
-148
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‎Runtime/Utility/HexMeshUtility.cs

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using System;
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using System.Collections.Generic;
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using UnityEngine;
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namespace Gameframe.Procgen
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{
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public enum HexDirection
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{
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NE = 0,
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E = 1,
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SE = 2,
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SW = 3,
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W = 4,
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NW = 5
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}
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public class HexMeshData
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{
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public float outerRadius;
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public float innerRadius;
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public List<Vector3> vertices;
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public List<int> triangles;
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public List<Color> colors;
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public Vector3[] corners;
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private float border = 0.25f;
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public float Border => border;
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public float Solid => 1 - border;
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public HexMeshData()
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{
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}
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public HexMeshData(float radius, float border = 0.2f)
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{
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this.border = Mathf.Clamp01(border);
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outerRadius = radius;
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innerRadius = outerRadius * Mathf.Sqrt(3f) * 0.5f;
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vertices = new List<Vector3>();
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triangles = new List<int>();
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colors = new List<Color>();
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corners = new [] {
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new Vector3(0f, 0f, outerRadius),
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new Vector3(innerRadius, 0f, 0.5f * outerRadius),
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new Vector3(innerRadius, 0f, -0.5f * outerRadius),
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new Vector3(0f, 0f, -outerRadius),
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new Vector3(-innerRadius, 0f, -0.5f * outerRadius),
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new Vector3(-innerRadius, 0f, 0.5f * outerRadius),
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new Vector3(0f, 0f, outerRadius)
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};
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}
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public Vector3 GetBridge(HexDirection direction)
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{
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return (corners[(int)direction] + corners[(int)direction + 1]) * 0.5f * border;
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}
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public Vector3 GetFirstCorner(HexDirection direction)
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{
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return corners[(int) direction];
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}
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public Vector3 GetSecondCorner(HexDirection direction)
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{
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return corners[(int) direction + 1];
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}
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public Vector3 GetFirstSolidCorner(HexDirection direction)
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{
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return corners[(int) direction] * Solid;
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}
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public Vector3 GetSecondSolidCorner(HexDirection direction)
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{
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return corners[(int) direction + 1] * Solid;
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}
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public Mesh CreateMesh()
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{
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Mesh mesh = new Mesh();
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mesh.vertices = vertices.ToArray();
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mesh.triangles = triangles.ToArray();
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mesh.colors = colors.ToArray();
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mesh.RecalculateNormals();
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return mesh;
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}
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}
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public static class HexMeshUtility
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{
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public static HexDirection Previous(this HexDirection direction)
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{
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return direction == HexDirection.NE ? HexDirection.NW : (direction - 1);
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}
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public static HexDirection Next(this HexDirection direction)
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{
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return direction == HexDirection.NW ? HexDirection.NE : (direction + 1);
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}
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public static int GetNeighbor(int index, HexDirection hexDirection, int mapWidth, int mapHeight)
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{
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int y = index / mapWidth;
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int x = index - (y * mapWidth);
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switch (hexDirection)
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{
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case HexDirection.NE:
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//Only odd numbered rows shift a column
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if ((y & 1) == 1)
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{
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x++;
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}
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y++;
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break;
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case HexDirection.E:
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x++;
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break;
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case HexDirection.SE:
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//Only odd numbered rows shift a column
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if ((y & 1) == 1)
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{
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x++;
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}
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y--;
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break;
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case HexDirection.SW:
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//Only even numbered rows shift a column
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if ((y & 1) == 0)
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{
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x--;
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}
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y--;
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break;
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case HexDirection.W:
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x--;
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break;
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case HexDirection.NW:
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//Only even numbered rows shift a column
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if ((y & 1) == 0)
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{
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x--;
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}
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y++;
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break;
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default:
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throw new ArgumentOutOfRangeException(nameof(hexDirection), hexDirection, null);
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}
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if (x < 0 || x >= mapWidth)
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{
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return -1;
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}
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if (y < 0 || y >= mapHeight)
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{
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return -1;
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}
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return y * mapWidth + x;
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}
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public static Mesh GenerateHexagonMesh(float radius, int startX, int startY, int chunkWidth, int chunkHeight, int mapWidth, int mapHeight, float[] heightMap, Func<float,Color> colorFunction, Func<float,float> elevationFunction)
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{
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var meshData = new HexMeshData(radius, 0.3f);
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for (int dy = 0; dy < chunkHeight && (startY + dy) < mapHeight; dy++)
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{
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for (int dx = 0; dx < chunkWidth && (startX + dx) < mapWidth; dx++)
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{
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int x = startX + dx;
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int y = startY + dy;
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var index = (y * mapWidth) + x;
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var xOffset = x + y * 0.5f - (int)(y / 2);
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var center = new Vector3(xOffset*meshData.innerRadius*2,0,y*meshData.outerRadius*1.5f);
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for (var direction = 0; direction < 6; direction++)
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{
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var elevation = elevationFunction?.Invoke(heightMap[index]) ?? 0;
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var previousNeighborElevation = elevation;
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var neighborElevation = elevation;
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var nextNeighborElevation = elevation;
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var neighbor = GetNeighbor(index, (HexDirection)direction, mapWidth, mapHeight);
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if (neighbor != -1)
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{
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neighborElevation = Mathf.Min(elevation,elevationFunction?.Invoke(heightMap[neighbor]) ?? 0);
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}
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neighbor = GetNeighbor(index, ((HexDirection)direction).Previous(), mapWidth, mapHeight);
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if (neighbor != -1)
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{
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previousNeighborElevation = Mathf.Min(elevation,elevationFunction?.Invoke(heightMap[neighbor]) ?? 0);
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}
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neighbor = GetNeighbor(index, ((HexDirection)direction).Next(), mapWidth, mapHeight);
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if (neighbor != -1)
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{
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nextNeighborElevation = Mathf.Min(elevation,elevationFunction?.Invoke(heightMap[neighbor]) ?? 0);
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}
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center.y = elevation;
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var color = colorFunction?.Invoke(heightMap[index]) ?? Color.white;
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AddTriangle(meshData, center, neighborElevation, previousNeighborElevation, nextNeighborElevation, (HexDirection)direction, color);
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}
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}
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}
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return meshData.CreateMesh();
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}
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private static void AddTriangle(HexMeshData meshData, Vector3 center, float neighborElevation, float previousElevation, float nextElevation, HexDirection direction, Color color)
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{
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var v1 = center;
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var v2 = center + meshData.GetFirstSolidCorner(direction);
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var v3 = center + meshData.GetSecondSolidCorner(direction);
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//Add inner solid triangle
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AddTriangle(meshData, v1, v2, v3, color);
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//Add Quad To Fill Border Gap
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var v4 = v2 + meshData.GetBridge(direction);
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v4.y = neighborElevation;
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var v5 = v3 + meshData.GetBridge(direction);
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v5.y = neighborElevation;
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AddQuad(meshData, v2, v3, v4, v5, color);
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//Add Triangles to fill gap on sides of quad
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var v6 = center + meshData.GetFirstCorner(direction);
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v6.y = Mathf.Min(neighborElevation,previousElevation);
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AddTriangle(meshData,v2, v6, v4, color);
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var v7 = center + meshData.GetSecondCorner(direction);
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v7.y = Mathf.Min(neighborElevation,nextElevation);
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AddTriangle(meshData,v3, v5, v7, color);
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}
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private static void AddTriangle(HexMeshData meshData, Vector3 v1, Vector3 v2, Vector3 v3, Color color)
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{
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var vertexIndex = meshData.vertices.Count;
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meshData.vertices.Add(v1);
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meshData.vertices.Add(v2);
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meshData.vertices.Add(v3);
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meshData.colors.Add(color);
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meshData.colors.Add(color);
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meshData.colors.Add(color);
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meshData.triangles.Add(vertexIndex);
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meshData.triangles.Add(vertexIndex + 1);
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meshData.triangles.Add(vertexIndex + 2);
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}
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private static void AddQuad(HexMeshData meshData, Vector3 v1, Vector3 v2, Vector3 v3, Vector3 v4, Color color)
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{
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var vertexIndex = meshData.vertices.Count;
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meshData.vertices.Add(v1);
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meshData.vertices.Add(v2);
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meshData.vertices.Add(v3);
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meshData.vertices.Add(v4);
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meshData.colors.Add(color);
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meshData.colors.Add(color);
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meshData.colors.Add(color);
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meshData.colors.Add(color);
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meshData.triangles.Add(vertexIndex);
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meshData.triangles.Add(vertexIndex + 2);
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meshData.triangles.Add(vertexIndex + 1);
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meshData.triangles.Add(vertexIndex + 1);
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meshData.triangles.Add(vertexIndex + 2);
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meshData.triangles.Add(vertexIndex + 3);
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}
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}
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}
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‎Runtime/Utility/HexMeshUtility.cs.meta

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