diff --git a/3rd/SDL/sync.py b/3rd/SDL/sync.py
new file mode 100755
index 000000000..dbb3d10a2
--- /dev/null
+++ b/3rd/SDL/sync.py
@@ -0,0 +1,24 @@
+#!/usr/bin/python
+
+import os
+import glob
+import copy
+import shutil
+import platform
+
+def joinPath(root, subdir):
+  return os.path.normpath(os.path.join(root, subdir))
+
+# XXX: make sure no no ascii chars in the path name.
+
+SRC_ROOT_DIR=joinPath(os.getcwd(), '../../../3rd/SDL/');
+DST_ROOT_DIR=os.getcwd();
+
+def copyFiles(src):
+    s = joinPath(SRC_ROOT_DIR, src)
+    d = joinPath(DST_ROOT_DIR, src)
+    print(s + '->' + d)
+    shutil.rmtree(d, True)
+    shutil.copytree(s, d)
+
+copyFiles('src');
diff --git a/3rd/agg/README.md b/3rd/agg/README.md
new file mode 100644
index 000000000..24f0b110f
--- /dev/null
+++ b/3rd/agg/README.md
@@ -0,0 +1,3 @@
+# Anti-Grain Geometry
+
+本目录从agg仓库同步而来：https://github.com/zlgopen/agg
diff --git a/3rd/agge/README.md b/3rd/agge/README.md
new file mode 100644
index 000000000..09ed9d2e3
--- /dev/null
+++ b/3rd/agge/README.md
@@ -0,0 +1,3 @@
+# Anti-Grain Evolution
+
+本目录从agge仓库同步而来：https://github.com/zlgopen/agge