代码以下:ide
using System.Collections; using System.Collections.Generic; using UnityEngine; using UnityEngine.UI; [AddComponentMenu("UI/Effects/Gradient")] public class Gradient : BaseMeshEffect { [SerializeField] private Color32 topColor = Color.white; [SerializeField] private Color32 bottomColor = Color.black; public override void ModifyMesh(VertexHelper vh) { if (!IsActive()) { return; } var vertexList = new List<UIVertex>(); vh.GetUIVertexStream(vertexList); int count = vertexList.Count; ApplyGradient(vertexList, 0, count); vh.Clear(); vh.AddUIVertexTriangleStream(vertexList); } private void ApplyGradient(List<UIVertex> vertexList, int start, int end) { float bottomY = vertexList[0].position.y; float topY = vertexList[0].position.y; for (int i = start; i < end; ++i) { float y = vertexList[i].position.y; if (y > topY) { topY = y; } else if (y < bottomY) { bottomY = y; } } float uiElementHeight = topY - bottomY; for (int i = start; i < end; ++i) { UIVertex uiVertex = vertexList[i]; uiVertex.color = Color32.Lerp(bottomColor, topColor, (uiVertex.position.y - bottomY)/uiElementHeight); vertexList[i] = uiVertex; } } }