From 7a6b8e102104fab8a446bb4313f98371638b2584 Mon Sep 17 00:00:00 2001
From: Jiang-Red <1343396474@qq.com>
Date: Wed, 11 Jan 2023 22:06:04 +0800
Subject: [PATCH] zbputils -> rendercard

---
 utils.go | 39 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 39 insertions(+)

diff --git a/utils.go b/utils.go
index 29db211..4efb0ff 100644
--- a/utils.go
+++ b/utils.go
@@ -3,6 +3,7 @@ package rendercard
 import (
 	"image"
 	"image/color"
+	"strings"
 
 	"github.com/Coloured-glaze/gg"
 )
@@ -40,3 +41,41 @@ func Transparency(dst image.Image, magnification float64) image.Image {
 	}
 	return dstr
 }
+
+// Truncate 截断文字
+func Truncate(fontfile string, texts []string, maxW, fontsize float64) ([]string, error) {
+	one := gg.NewContext(1, 1)
+	err := one.LoadFontFace(fontfile, fontsize)
+	if err != nil {
+		return nil, err
+	}
+	newtexts := make([]string, 0, len(texts)*2)
+	for i := 0; i < len(texts); i++ {
+		newlinetext, textw, tmpw := "", 0.0, 0.0
+		text := texts[i]
+		for len(texts[i]) > 0 {
+			var tmp strings.Builder
+			tmp.Grow(len(text))
+			res := make([]rune, 0, len(text))
+			for _, r := range text {
+				tmp.WriteRune(r)
+				width, _ := one.MeasureString(tmp.String()) // 获取文字宽度
+				if width > maxW {                           // 如果宽度大于文字边距
+					break // 跳出
+				} else {
+					res = append(res, r) // 写入
+				}
+				newlinetext = string(res)
+			}
+			newtexts = append(newtexts, newlinetext)
+			if tmpw > textw {
+				textw = tmpw
+			}
+			if len(newlinetext) >= len(texts[i]) {
+				break
+			}
+			texts[i] = texts[i][len(newlinetext):]
+		}
+	}
+	return newtexts, nil
+}