From 467b2c2739dfda204d9ceeee17755ee53041aae4 Mon Sep 17 00:00:00 2001
From: Du Yifeng <a4r5t6y@yeah.net>
Date: Mon, 25 May 2026 20:43:43 +0800
Subject: [PATCH] [FIX] fixed an issue that Chinese, Japanese and Korean
 characters dont display correctly on graph

Configures Matplotlib font fallback stack to include available system CJK fonts.
This ensures Chinese, Japanese, and Korean characters render correctly in graphs.
---
 graphs/gui/canvasPanel.py |  2 +
 graphs/mpl_fonts.py       | 84 +++++++++++++++++++++++++++++++++++++++
 2 files changed, 86 insertions(+)
 create mode 100644 graphs/mpl_fonts.py

diff --git a/graphs/gui/canvasPanel.py b/graphs/gui/canvasPanel.py
index 4c862f6001..47ab4199ee 100644
--- a/graphs/gui/canvasPanel.py
+++ b/graphs/gui/canvasPanel.py
@@ -30,6 +30,7 @@
 from logbook import Logger
 
 
+from graphs.mpl_fonts import configure_matplotlib_font
 from graphs.style import BASE_COLORS, LIGHTNESSES, STYLES, hsl_to_hsv
 from gui.utils.numberFormatter import roundToPrec
 
@@ -43,6 +44,7 @@
     mpl_version = int(mpl.__version__[0]) or -1
     if mpl_version >= 2:
         mpl.use('wxagg')
+        configure_matplotlib_font()
         graphFrame_enabled = True
     else:
         graphFrame_enabled = False
diff --git a/graphs/mpl_fonts.py b/graphs/mpl_fonts.py
new file mode 100644
index 0000000000..75d5977445
--- /dev/null
+++ b/graphs/mpl_fonts.py
@@ -0,0 +1,84 @@
+# =============================================================================
+# Copyright (C) 2026 Du Yifeng
+#
+# This file is part of pyfa.
+#
+# pyfa is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+#
+# pyfa is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with pyfa.  If not, see <http://www.gnu.org/licenses/>.
+# =============================================================================
+"""
+Configures Matplotlib font fallback stack to include available system CJK fonts.
+This ensures Chinese, Japanese, and Korean characters render correctly in graphs.
+"""
+
+import platform
+
+
+def configure_matplotlib_font():
+    """
+    Configure matplotlib to use fonts that can render CJK text.
+    """
+    try:
+        import matplotlib as mpl
+        from matplotlib import font_manager
+    except ImportError:
+        return
+
+    candidates = []
+
+    try:
+        # noinspection PyPackageRequirements
+        import wx
+        gui_face = wx.SystemSettings.GetFont(wx.SYS_DEFAULT_GUI_FONT).GetFaceName()
+        if gui_face:
+            candidates.append(gui_face)
+    except Exception:
+        pass
+
+    candidates.extend([
+        'Noto Sans CJK KR', 'Noto Sans CJK JP', 'Noto Sans CJK SC', 'Noto Sans CJK TC',
+        'Source Han Sans KR', 'Source Han Sans JP', 'Source Han Sans CN', 'Source Han Sans TW',
+    ])
+
+    system = platform.system()
+    if system == 'Windows':
+        candidates.extend([
+            'Microsoft YaHei', 'Microsoft JhengHei', 'SimHei', 'SimSun',
+            'Malgun Gothic', 'Gulim', 'Dotum', 'Batang',
+            'Yu Gothic', 'Meiryo', 'Arial Unicode MS',
+        ])
+    elif system == 'Darwin':
+        candidates.extend([
+            'Apple SD Gothic Neo', 'AppleGothic', 'PingFang SC', 'PingFang TC',
+            'Hiragino Sans GB', 'Hiragino Sans', 'Heiti SC', 'Arial Unicode MS',
+        ])
+    else:
+        candidates.extend([
+            'NanumGothic', 'UnDotum', 'WenQuanYi Micro Hei', 'WenQuanYi Zen Hei',
+            'Droid Sans Fallback',
+        ])
+
+    candidates.append('DejaVu Sans')
+
+    # Filter out unavailable fonts to prevent Matplotlib warnings
+    available = {f.name for f in font_manager.fontManager.ttflist}
+    
+    resolved = []
+    for name in candidates:
+        if name in available and name not in resolved:
+            resolved.append(name)
+
+    if resolved:
+        mpl.rcParams['font.family'] = resolved
+
+    mpl.rcParams['axes.unicode_minus'] = False