v2.0.07-20230405

system/ico.php

@@ -0,0 +1,80 @@
+<?php
+//首字母头像
+output_ico(); 
+ 
+//输出svg图像
+function output_ico() {
+    //防盗链
+    if(empty($_SERVER['HTTP_REFERER']) || !strstr($_SERVER['HTTP_REFERER'],$_SERVER['HTTP_HOST'])){
+        header('HTTP/1.1 404 Not Found');header("status: 404 Not Found");exit('404 Not Found');
+    }
+    
+    $text = $_GET['text'] ?? '空';
+    header('Cache-Control: max-age=604800');
+    header('Content-Type:image/svg+xml');
+    echo letter_avatar($text);
+}
+
+
+function letter_avatar($text){
+    $total = unpack('L', hash('adler32', $text, true))[1];
+    $hue = $total % 360;
+    list($r, $g, $b) = hsv2rgb($hue / 360, 0.3, 0.9);
+
+    $bg = "rgb({$r},{$g},{$b})";
+    $color = "#ffffff";
+    $first = mb_strtoupper(mb_substr($text, 0, 1));
+    $src = '<svg xmlns="http://www.w3.org/2000/svg" version="1.1" height="100" width="100"><rect fill="' . $bg . '" x="0" y="0" width="100" height="100"></rect><text x="50" y="50" font-size="50" text-copy="fast" fill="' . $color . '" text-anchor="middle" text-rights="admin" alignment-baseline="central">' . $first . '</text></svg>';
+    $value = $src;
+    return $value;
+}
+
+
+function hsv2rgb($h, $s, $v){
+    $r = $g = $b = 0;
+    $i = floor($h * 6);
+    $f = $h * 6 - $i;
+    $p = $v * (1 - $s);
+    $q = $v * (1 - $f * $s);
+    $t = $v * (1 - (1 - $f) * $s);
+
+    switch ($i % 6) {
+        case 0:
+            $r = $v;
+            $g = $t;
+            $b = $p;
+            break;
+        case 1:
+            $r = $q;
+            $g = $v;
+            $b = $p;
+            break;
+        case 2:
+            $r = $p;
+            $g = $v;
+            $b = $t;
+            break;
+        case 3:
+            $r = $p;
+            $g = $q;
+            $b = $v;
+            break;
+        case 4:
+            $r = $t;
+            $g = $p;
+            $b = $v;
+            break;
+        case 5:
+            $r = $v;
+            $g = $p;
+            $b = $q;
+            break;
+    }
+
+    return [
+        floor($r * 255),
+        floor($g * 255),
+        floor($b * 255)
+    ];
+}
+