[feature][API] add SaveAsImage()

CHANGELOG.md

@@ -58,6 +58,7 @@
 
 ## master
 
+* (2022.09.22) 增加`SaveAsImage()`接口保存图表到图片
 * (2022.09.21) 修复`InsertSerie()`接口不刷新图表的问题
 * (2022.09.21) 优化`PolarChart`对`Line`热力图的支持
 * (2022.09.20) 增加`PolarChart`对`Heatmap`热力图的支持

Editor/Charts/BaseChartEditor.cs

@@ -16,6 +16,7 @@ namespace XCharts.Editor
             public static readonly GUIContent btnAddComponent = new GUIContent("Add Main Component", "");
             public static readonly GUIContent btnCovertXYAxis = new GUIContent("Covert XY Axis", "");
             public static readonly GUIContent btnRebuildChartObject = new GUIContent("Rebuild Chart Object", "");
+            public static readonly GUIContent btnSaveAsImage = new GUIContent("Save As Image", "");
             public static readonly GUIContent btnCheckWarning = new GUIContent("Check Warning", "");
             public static readonly GUIContent btnHideWarning = new GUIContent("Hide Warning", "");
         }
@@ -279,6 +280,10 @@ namespace XCharts.Editor
             {
                 m_Chart.RebuildChartObject();
             }
+            if (GUILayout.Button(Styles.btnSaveAsImage))
+            {
+                m_Chart.SaveAsImage();
+            }
             if (m_CheckWarning)
             {
                 EditorGUILayout.BeginHorizontal();

Plugins.meta

@@ -0,0 +1,8 @@
+fileFormatVersion: 2
+guid: 6558d1464a47441d18df18c4a403b2f2
+folderAsset: yes
+DefaultImporter:
+  externalObjects: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Plugins/Download.jslib

@@ -0,0 +1,24 @@
+mergeInto(LibraryManager.library, {
+    Download: function (str, fn) {
+        var msg = UTF8ToString(str);
+        var fname = UTF8ToString(fn);
+        function fixBinary(bin) {
+            var length = bin.length;
+            var buf = new ArrayBuffer(length);
+            var arr = new Uint8Array(buf);
+            for (var i = 0; i < length; i++) {
+                arr[i] = bin.charCodeAt(i);
+            }
+            return buf;
+        }
+        var binary = fixBinary(atob(msg));
+        var data = new Blob([binary]);
+        var link = document.createElement('a');
+        link.download = fname;
+        link.href = URL.createObjectURL(data);
+        document.body.appendChild(link);
+        link.click();
+        document.body.removeChild(link);
+    }
+});
+

Plugins/Download.jslib.meta

@@ -0,0 +1,34 @@
+fileFormatVersion: 2
+guid: 821b9cd60f13648a396c76481da2191c
+PluginImporter:
+  externalObjects: {}
+  serializedVersion: 2
+  iconMap: {}
+  executionOrder: {}
+  isPreloaded: 0
+  isOverridable: 0
+  platformData:
+  - first:
+      Any: 
+    second:
+      enabled: 0
+      settings: {}
+  - first:
+      Editor: Editor
+    second:
+      enabled: 0
+      settings:
+        DefaultValueInitialized: true
+  - first:
+      Facebook: WebGL
+    second:
+      enabled: 1
+      settings: {}
+  - first:
+      WebGL: WebGL
+    second:
+      enabled: 1
+      settings: {}
+  userData: 
+  assetBundleName: 
+  assetBundleVariant: 

Runtime/Internal/BaseChart.API.cs

@@ -588,5 +588,15 @@ namespace XCharts.Runtime
             SerieHelper.GetItemColor(out color, out toColor, serie, null, m_Theme);
             return color;
         }
+
+        /// <summary>
+        /// 保存图表为图片。
+        /// </summary>
+        /// <param name="imageType">type of image: png, jpg, exr</param>
+        /// <param name="savePath">save path</param>
+        public void SaveAsImage(string imageType = "png", string savePath = "")
+        {
+            StartCoroutine(SaveAsImageSync(imageType, savePath));
+        }
     }
 }

Runtime/Internal/BaseChart.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections;
 using System.Collections.Generic;
 using System.Reflection;
 using UnityEngine;
@@ -741,5 +742,11 @@ namespace XCharts.Runtime
             InitComponentHandlers();
             InitSerieHandlers();
         }
+
+        private IEnumerator SaveAsImageSync(string imageType, string path)
+        {
+            yield return new WaitForEndOfFrame();
+            ChartHelper.SaveAsImage(rectTransform, canvas, imageType, path);
+        }
     }
 }

Runtime/Internal/Utilities/ChartHelper.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Runtime.InteropServices;
 using System.Text;
 using System.Text.RegularExpressions;
 using UnityEngine;
@@ -896,5 +897,62 @@ namespace XCharts.Runtime
             if (valueOrRate >= -maxRate && valueOrRate <= maxRate) return valueOrRate * total;
             else return valueOrRate;
         }
+
+        [DllImport("__Internal")]
+        private static extern void Download(string base64str, string fileName);
+
+        public static Texture2D SaveAsImage(RectTransform rectTransform, Canvas canvas, string imageType = "png", string path = "")
+        {
+            var cam = canvas.renderMode == RenderMode.ScreenSpaceOverlay ? null : canvas.worldCamera;
+            var pos = RectTransformUtility.WorldToScreenPoint(cam, rectTransform.position);
+            var width = rectTransform.rect.width * canvas.scaleFactor;
+            var height = rectTransform.rect.height * canvas.scaleFactor;
+            var posX = pos.x + rectTransform.rect.xMin * canvas.scaleFactor;
+            var posY = pos.y + rectTransform.rect.yMin * canvas.scaleFactor;
+            var rect = new Rect(posX, posY, width, height);
+            var tex = new Texture2D((int) width, (int) height, TextureFormat.RGBA32, false);
+            tex.ReadPixels(rect, 0, 0);
+            tex.Apply();
+            byte[] bytes;
+            switch (imageType)
+            {
+                case "png":
+                    bytes = tex.EncodeToPNG();
+                    break;
+                case "jpg":
+                    bytes = tex.EncodeToJPG();
+                    break;
+                case "exr":
+                    bytes = tex.EncodeToEXR();
+                    break;
+                default:
+                    Debug.LogError("SaveAsImage ERROR: not support image type:" + imageType);
+                    return null;
+            }
+            var fileName = rectTransform.name + "." + imageType;
+#if UNITY_WEBGL
+            string base64str = Convert.ToBase64String(bytes);
+            Download(base64str, fileName);
+            Debug.Log("SaveAsImage: download by brower:" + fileName);
+            return tex;
+#endif
+            if (string.IsNullOrEmpty(path))
+            {
+                var dir = Application.persistentDataPath + "/SavedImage";
+#if UNITY_EDITOR
+                dir = Application.dataPath + "/../SavedImage";
+#else
+                dir = Application.persistentDataPath + "/SavedImage";
+#endif
+                if (!System.IO.Directory.Exists(dir))
+                {
+                    System.IO.Directory.CreateDirectory(dir);
+                }
+                path = dir + "/" + fileName;
+            }
+            System.IO.File.WriteAllBytes(path, bytes);
+            Debug.Log("SaveAsImage:" + path);
+            return tex;
+        }
     }
 }