From a05213020a90539f0ab659d697fbea920c94af53 Mon Sep 17 00:00:00 2001
From: kekee000 <kekee000@gmail.com>
Date: Sat, 9 Nov 2019 22:30:39 +0800
Subject: [PATCH] add support options to ttfwriter

---
 README.md                       |  1 +
 package.json                    |  2 +-
 src/ttf/table/OS2.js            | 33 ++++++++++++++++++
 src/ttf/ttfwriter.js            |  5 +--
 test/spec/ttf/ttfwriter.spec.js | 61 +++++++++++++++++++++++++++++++++
 5 files changed, 99 insertions(+), 3 deletions(-)

diff --git a/README.md b/README.md
index 73d1b5d..1977a7d 100644
--- a/README.md
+++ b/README.md
@@ -64,6 +64,7 @@ let buffer = font.write({
   type: 'woff', // support ttf, woff, woff2, eot, svg
   hinting: true, // save font hinting
   deflate: null, // deflate function for woff
+  support: {head: {}, hhea: {}} // for user to overwrite head.xMin, head.xMax, head.yMin, head.yMax, hhea etc.
 });
 // fs.writeFileSync('font.woff', buffer);
 
diff --git a/package.json b/package.json
index 88a66a9..90212f5 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "fonteditor-core",
-  "version": "2.0.6",
+  "version": "2.0.7",
   "description": "fonts (ttf, woff, woff2, eot, svg, otf) parse, write, transform, glyph adjust.",
   "keywords": [
     "sfnt",
diff --git a/src/ttf/table/OS2.js b/src/ttf/table/OS2.js
index b89d480..8c8ac99 100644
--- a/src/ttf/table/OS2.js
+++ b/src/ttf/table/OS2.js
@@ -265,6 +265,39 @@ export default table.create(
             ttf.head.xMax = xMax;
             ttf.head.yMax = yMax;
 
+            // head rewrite
+            if (ttf.support.head) {
+                let {xMin, yMin, xMax, yMax} = ttf.support.head;
+                if (xMin != null) {
+                    ttf.head.xMin = xMin;
+                }
+                if (yMin != null) {
+                    ttf.head.yMin = yMin;
+                }
+                if (xMax != null) {
+                    ttf.head.xMax = xMax;
+                }
+                if (yMax != null) {
+                    ttf.head.yMax = yMax;
+                }
+
+            }
+            // hhea rewrite
+            if (ttf.support.hhea) {
+                let {advanceWidthMax, xMaxExtent, minLeftSideBearing, minRightSideBearing} = ttf.support.hhea;
+                if (advanceWidthMax != null) {
+                    ttf.hhea.advanceWidthMax = advanceWidthMax;
+                }
+                if (xMaxExtent != null) {
+                    ttf.hhea.xMaxExtent = xMaxExtent;
+                }
+                if (minLeftSideBearing != null) {
+                    ttf.hhea.minLeftSideBearing = minLeftSideBearing;
+                }
+                if (minRightSideBearing != null) {
+                    ttf.hhea.minRightSideBearing = minRightSideBearing;
+                }
+            }
             // 这里根据存储的maxp来设置新的maxp，避免重复计算maxp
             ttf.maxp = ttf.maxp || {};
             ttf.support.maxp = {
diff --git a/src/ttf/ttfwriter.js b/src/ttf/ttfwriter.js
index 246a26e..68a34ed 100644
--- a/src/ttf/ttfwriter.js
+++ b/src/ttf/ttfwriter.js
@@ -26,7 +26,8 @@ const SUPPORT_TABLES = [
 export default class TTFWriter {
     constructor(options = {}) {
         this.options = {
-            hinting: options.hinting || false // 不保留hints信息
+            hinting: options.hinting || false, // 不保留hints信息
+            support: options.support // 自定义的导出表结构，可以自己修改某些表项目
         };
     }
 
@@ -96,7 +97,7 @@ export default class TTFWriter {
     dump(ttf) {
 
         // 用来做写入缓存的对象，用完后删掉
-        ttf.support = {};
+        ttf.support = Object.assign({}, this.options.support);
 
         // head + directory
         let ttfSize = 12 + ttf.numTables * 16;
diff --git a/test/spec/ttf/ttfwriter.spec.js b/test/spec/ttf/ttfwriter.spec.js
index c02041f..eea05c4 100644
--- a/test/spec/ttf/ttfwriter.spec.js
+++ b/test/spec/ttf/ttfwriter.spec.js
@@ -49,6 +49,67 @@ describe('写ttf数据', function () {
 
     });
 
+    it('test write ttf with support', function () {
+        let buffer = new TTFWriter({
+            support: {
+                head: {
+                    xMin: 1,
+                    yMin: -30,
+                    xMax: 610,
+                    yMax: 485,
+                    minLeftSideBearing: 1,
+                    minRightSideBearing: 1
+                },
+                hhea: {
+                    advanceWidthMax: 1000,
+                    xMaxExtent: 1000,
+                    minLeftSideBearing: 1,
+                    minRightSideBearing: 1
+                }
+            }
+        }).write(fontObject);
+
+        assert.ok(buffer.byteLength > 1000);
+        assert.ok(buffer.byteLength < 10000);
+
+        let ttf = new TTFReader().read(buffer);
+
+        assert.equal(ttf.version, 1);
+
+        assert.equal(ttf.head.magickNumber, 1594834165);
+        assert.equal(ttf.head.unitsPerEm, 512);
+
+        assert.equal(ttf.post.format, 2);
+        assert.equal(ttf.post.underlinePosition, 0);
+        assert.equal(ttf.post.underlineThickness, 0);
+
+        assert.equal(ttf.hhea.ascent, 480);
+        assert.equal(ttf.hhea.descent, -33);
+
+        assert.equal(ttf.maxp.version, 1);
+        assert.equal(ttf.maxp.numGlyphs, 17);
+
+        assert.equal(ttf.glyf[0].advanceWidth, 512);
+        assert.equal(ttf.glyf[0].leftSideBearing, 0);
+        assert.equal(ttf.glyf[0].name, '.notdef');
+        assert.equal(ttf.glyf[3].contours[0].length, 31);
+        assert.equal(ttf.glyf[16].compound, true);
+        assert.equal(ttf.glyf[16].glyfs.length, 2);
+
+        assert.equal(ttf.cmap[0], 1);
+        assert.equal(ttf.cmap[57400], 16);
+        assert.equal(+ttf.head.created === +fontObject.head.created, true);
+        assert.equal(+ttf.head.modified === +fontObject.head.modified, true);
+        assert.equal(ttf.head.xMin, 1);
+        assert.equal(ttf.head.yMin, -30);
+        assert.equal(ttf.head.xMax, 610);
+        assert.equal(ttf.head.yMax, 485);
+        assert.equal(ttf.hhea.advanceWidthMax, 1000);
+        assert.equal(ttf.hhea.xMaxExtent, 1000);
+        assert.equal(ttf.hhea.minLeftSideBearing, 1);
+        assert.equal(ttf.hhea.minRightSideBearing, 1);
+    });
+
     it('test write ttf error', function () {
         assert.throws(function () {
             let ttf = Object.assign({}, fontObject);