feat: 首次提交

components/firstui/fui-autograph/gcanvas/env/tool.js

@@ -0,0 +1,25 @@
+// 本文件由FirstUI授权予新疆天衡创新研究院有限公司（手机号：1 8  6 14  0  7 2 549，身份证尾号：5A07X5）专用，请尊重知识产权，勿私下传播，违者追究法律责任。
+
+export function ArrayBufferToBase64 (buffer) {
+    var binary = '';
+    var bytes = new Uint8ClampedArray(buffer);
+    for (var len = bytes.byteLength, i = 0; i < len; i++) {
+        binary += String.fromCharCode(bytes[i]);
+    }
+    return btoa(binary);
+}
+
+export function Base64ToUint8ClampedArray(base64String) {
+	const padding = '='.repeat((4 - base64String.length % 4) % 4);
+	const base64 = (base64String + padding)
+		.replace(/\-/g, '+')
+		.replace(/_/g, '/');
+
+	const rawData = atob(base64);
+	const outputArray = new Uint8ClampedArray(rawData.length);
+
+	for (let i = 0; i < rawData.length; ++i) {
+		outputArray[i] = rawData.charCodeAt(i);
+	}
+	return outputArray;
+}