Procedural Mesh based on Curve Tool
Developed a tool to generate a art-direct-able procedural mesh in real-time based on curve shape.
Unity did not have a curve editor so curve editor itself was created by me as well.
Wrote shaders to support its look properly.
C#, HLSL, Unity
Inspired by Zelda: Breath of the wind's magnet VFX
1. Mesh is generated with a custom curve (curve editor itself is also developed since Unity does not have one)
2. Mesh's shape is creatively modified with animation curve tool and curve shape itself. (Watch video starting at 1:37 below for detail)
using System.Collections.Generic;using UnityEngine;[ExecuteInEditMode]public class ProceduralMeshGenerator : BezierCurveBase{ public enum OrientEnum { XOriented, YOriented, ZOriented }; [Header("Create Procedural Mesh")] public GameObject MeshObj; public bool CreateMesh = false; public bool IsTwoSided = true; public OrientEnum Orient; public bool FlipSide = false; public bool FlipUV = false; public float CustomCurveMultL = 1.0f; public float CustomCurveMultR = 1.0f; //let's say you edit from inspector, but you can built at runtime if you prefer public AnimationCurve CurveL = AnimationCurve.Linear(0f, 1f, 1f, 1f); //AnimationCurve.EaseInOut(0f, 0.1f, 1f, 0.9f); //let's say you edit from inspector, but you can built at runtime if you prefer public AnimationCurve CurveR = AnimationCurve.Linear(0f, 1f, 1f, 1f); // AnimationCurve.EaseInOut(0f, 0.1f, 1f, 0.9f); private MeshFilter Filter; private List<Vector3> Vertices = new List<Vector3>(); private List<Vector2> UVs = new List<Vector2>(); private List<int> Triangles = new List<int>(); private Vector3[] CrossVectors = new Vector3[2]; private Mesh ProceduralMesh; protected override void Update() { base.Update(); if (CreateMesh) { if (!MeshObj) { MeshObj = new GameObject(); MeshObj.AddComponent<MeshFilter>(); MeshObj.AddComponent<MeshRenderer>(); MeshObj.transform.parent = transform; MeshObj.transform.position = new Vector3(0f, 0f, 0f); MeshObj.transform.localScale = new Vector3(1f, 1f, 1f); MeshObj.name = "ProceduralMesh"; Filter = MeshObj.GetComponent<MeshFilter>(); Filter.sharedMesh = new Mesh(); } else if (MeshObj && !Filter) { Filter = MeshObj.GetComponent<MeshFilter>(); Filter.sharedMesh = new Mesh(); } CreateProceduralMesh(); } else if (MeshObj && Filter) { RemoveProceduralMesh(); } } private void CreateProceduralMesh() { Vertices.Clear(); Triangles.Clear(); UVs.Clear(); Vector3[] pos = new Vector3[Resolution]; GetCorePoints(ref pos); float t; float lastId = (float)(pos.Length - 1); for (int i = 0; i < pos.Length; i++) { t = i / (lastId); // 0.0 ~ 1.0 CalculateSideVectors(ref pos, i, CustomCurveMultR * CurveR.Evaluate(t), CustomCurveMultL * CurveL.Evaluate(t)); AddCurvePoint(CrossVectors[1], CrossVectors[0], i, pos.Length - 1); } Mesh mesh = Filter.sharedMesh; mesh.Clear(); /* Vector3[] normales = new Vector3[vertices.Length]; for (int n = 0; n < normales.Length; n++) normales[n] = Vector3.up; */ mesh.vertices = Vertices.ToArray(); //mesh.normals = normales; mesh.uv = UVs.ToArray(); mesh.triangles = Triangles.ToArray(); mesh.RecalculateBounds(); //mesh.RecalculateNormals(); if (MeshObj != null) { MeshObj.transform.position = Vector3.zero; MeshObj.transform.localScale = Vector3.one; MeshObj.transform.rotation = Quaternion.identity; } } private void RemoveProceduralMesh() { Vertices.Clear(); Triangles.Clear(); UVs.Clear(); Mesh mesh = Filter.sharedMesh; mesh.Clear(); DestroyImmediate(MeshObj); } private void CalculateSideVectors(ref Vector3[] pos, int i, float WidthR, float WidthL) { Vector3 tangent; if (i + 1 >= pos.Length) { tangent = (pos[i] - pos[i - 1]).normalized; } else tangent = (pos[i + 1] - pos[i]).normalized; float sign = 1f; //if (FlipSide) // sign = -1f; Vector3 upvector = new Vector3(sign, pos[i].y, pos[i].z); // XOriented as default if (Orient == OrientEnum.YOriented) upvector = new Vector3(pos[i].x, sign, pos[i].z); else if (Orient == OrientEnum.ZOriented) upvector = new Vector3(pos[i].x, pos[i].y, sign); Vector3 toUpvector = (upvector - pos[i]); Vector3 CrossL = Vector3.Cross(tangent, toUpvector).normalized; Vector3 CrossR = CrossL * -1f; Vector3 r = pos[i] + CrossR * WidthR; Vector3 l = pos[i] + CrossL * WidthL; CrossVectors[0] = r; CrossVectors[1] = l; } private void GetCorePoints(ref Vector3[] pos) { Vector3 prevPos = P0.transform.position; pos[0] = prevPos; float lastId = (float)(Resolution - 1); for (int c = 1; c < Resolution; c++) { float t = c / lastId; pos[c] = CurveMath.CalculateBezierPoint(t, P0.transform.position, P0_Tangent.transform.position, P1_Tangent.transform.position, P1.transform.position); prevPos = pos[c]; } } private void AddCurvePoint(Vector3 R, Vector3 L, int id, int count) { int start; Vertices.Add(R); Vertices.Add(L); if (FlipUV) { UVs.Add(new Vector2(0f, (float)id / count)); UVs.Add(new Vector2(1f, (float)id / count)); } else { UVs.Add(new Vector2((float)id / count, 0f)); UVs.Add(new Vector2((float)id / count, 1f)); } if (FlipSide) { if (Vertices.Count >= 4) { start = Vertices.Count - 4; Triangles.Add(start + 0); Triangles.Add(start + 2); Triangles.Add(start + 1); Triangles.Add(start + 1); Triangles.Add(start + 2); Triangles.Add(start + 3); // also create side for back so its two sided rendering mesh ,. or use custom shader if (IsTwoSided) { start = Vertices.Count - 4; Triangles.Add(start + 0); Triangles.Add(start + 1); Triangles.Add(start + 2); Triangles.Add(start + 1); Triangles.Add(start + 3); Triangles.Add(start + 2); } } } else { if (Vertices.Count >= 4) { start = Vertices.Count - 4; Triangles.Add(start + 0); Triangles.Add(start + 1); Triangles.Add(start + 2); Triangles.Add(start + 1); Triangles.Add(start + 3); Triangles.Add(start + 2); // also create side for back so its two sided rendering mesh ,. or use custom shader if (IsTwoSided) { start = Vertices.Count - 4; Triangles.Add(start + 0); Triangles.Add(start + 2); Triangles.Add(start + 1); Triangles.Add(start + 1); Triangles.Add(start + 2); Triangles.Add(start + 3); } } } } public override void OnDestroy() { base.OnDestroy(); DestroyImmediate(MeshObj); }}