From bad1e6c76c0373668f8d2b0b37bf5a1b31ef844b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E4=B8=80=E4=B8=9D?= <percyley@qq.com>
Date: Tue, 14 Feb 2023 21:23:59 +0800
Subject: [PATCH] feat: improve custom loaded fonts

---
 Cargo.toml      |  2 ++
 example/text.js | 32 ++++++++++++++++++++++++++++++++
 src/fonts.rs    | 36 +++++++++++++++++++++++++++++++++++-
 3 files changed, 69 insertions(+), 1 deletion(-)

diff --git a/Cargo.toml b/Cargo.toml
index 77b50ce9..ef92967a 100755
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -22,6 +22,7 @@ pathfinder_content = { version = "0.5.0", default-features = false }
 pathfinder_simd = { version = "0.5.1", features = ["pf-no-simd"] }
 futures = "0.3.21"
 usvg-writer = { git = "https://github.com/zimond/resvg", rev = "6201182c" }
+# usvg-writer = { path = "../resvg/usvg-writer" }
 
 [target.'cfg(all(not(all(target_os = "linux", target_arch = "aarch64", target_env = "musl")), not(all(target_os = "windows", target_arch = "aarch64")), not(target_arch = "wasm32")))'.dependencies]
 mimalloc-rust = { version = "0.2" }
@@ -57,3 +58,4 @@ codegen-units = 1
 
 [patch.crates-io]
 resvg = { git = "https://github.com/zimond/resvg", rev = "6201182c" }
+# resvg = { path = "../resvg" }
diff --git a/example/text.js b/example/text.js
index 29104e98..2e37515c 100644
--- a/example/text.js
+++ b/example/text.js
@@ -30,3 +30,35 @@ async function main() {
 }
 
 main()
+const { promises } = require('fs')
+const { join } = require('path')
+const { performance } = require('perf_hooks')
+
+const { Resvg } = require('../index')
+
+async function main() {
+  const svg = `
+  <svg xmlns="http://www.w3.org/2000/svg" width="200" height="200" viewBox="0 0 200 200">
+    <text fill="blue" font-family="serif" font-size="120">
+      <tspan x="40" y="143">水</tspan>
+    </text>
+  </svg>
+  `
+  const t = performance.now()
+  const resvg = new Resvg(svg, {
+    // background: 'pink',
+    font: {
+      fontFiles: ['./example/SourceHanSerifCN-Light-subset.ttf'], // Load custom fonts.
+      loadSystemFonts: false, // It will be faster to disable loading system fonts.
+      // defaultFontFamily: 'SourceHanSerifCN-Light',
+    },
+    logLevel: 'debug', // Default Value: error
+  })
+  const pngData = resvg.render()
+  const pngBuffer = pngData.asPng()
+  console.info('✨ Done in', performance.now() - t, 'ms')
+
+  await promises.writeFile(join(__dirname, './text2-out.png'), pngBuffer)
+}
+
+main()
diff --git a/src/fonts.rs b/src/fonts.rs
index 52210acc..7d525434 100644
--- a/src/fonts.rs
+++ b/src/fonts.rs
@@ -9,7 +9,7 @@ use crate::options::*;
 use log::{debug, warn};
 
 #[cfg(not(target_arch = "wasm32"))]
-use resvg::usvg_text_layout::fontdb::{Database, Family, Query, Source};
+use resvg::usvg_text_layout::fontdb::{Database, Family, Language, Query, Source};
 
 /// Loads fonts.
 #[cfg(not(target_arch = "wasm32"))]
@@ -62,6 +62,40 @@ pub fn load_fonts(font_options: &JsFontOptions) -> Database {
         fontdb.len(),
         now.elapsed().as_micros() as f64 / 1000.0
     );
+    let mut default_font_family = font_options.default_font_family.clone();
+    // 当默认字体为空时，尝试直接从 font_files 中加载读取字体名称，然后设置到默认的 font-family 中
+    // TODO: 判断只有 font_files 没有 default_font_family 选项的情况
+    if !font_options.default_font_family.is_empty() && font_options.font_files.len() > 0 {
+        fontdb.faces().into_iter().for_each(|face| {
+            let new_family = face
+                .families
+                .iter()
+                .find(|f| f.1 == Language::English_UnitedStates)
+                .unwrap();
+            default_font_family = new_family.0.clone();
+        });
+
+        // If a default font family exists, set all other families to that family.
+        // This prevents fonts from not being rendered in SVG.
+        fontdb.set_serif_family(&default_font_family);
+        fontdb.set_sans_serif_family(&default_font_family);
+        fontdb.set_cursive_family(&default_font_family);
+        fontdb.set_fantasy_family(&default_font_family);
+        fontdb.set_monospace_family(&default_font_family);
+    } else {
+        // Set generic font families
+        // - `serif` - Times New Roman
+        // - `sans-serif` - Arial
+        // - `cursive` - Comic Sans MS
+        // - `fantasy` - Impact (Papyrus on macOS)
+        // - `monospace` - Courier New
+        fontdb.set_serif_family(&font_options.serif_family);
+        fontdb.set_sans_serif_family(&font_options.sans_serif_family);
+        fontdb.set_cursive_family(&font_options.cursive_family);
+        fontdb.set_fantasy_family(&font_options.fantasy_family);
+        fontdb.set_monospace_family(&font_options.monospace_family);
+    }
+    debug!("默认字体 = {} ", font_options.default_font_family,);
 
     // 查找指定字体的路径
     let font_family: &str = &font_options.default_font_family;