From fadbcd91e5f77019d9ec3e346247e3c8ded46f87 Mon Sep 17 00:00:00 2001
From: Sam Edwards <CFSworks@gmail.com>
Date: Sat, 31 Mar 2018 05:22:04 -0600
Subject: [PATCH 01/17] ffmpeg: Bump supported minimums lower for libav 9.20

We need to support this because Ubuntu 14.04 ships with this
version, and has no "backports" option to bring in a newer version
(without use of a PPA or compiling it yourself).

We can consider raising the minimums again once Trusty is EOL.
---
 panda/src/ffmpeg/config_ffmpeg.cxx | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/panda/src/ffmpeg/config_ffmpeg.cxx b/panda/src/ffmpeg/config_ffmpeg.cxx
index be788eb2f8..850cf62937 100644
--- a/panda/src/ffmpeg/config_ffmpeg.cxx
+++ b/panda/src/ffmpeg/config_ffmpeg.cxx
@@ -30,16 +30,19 @@ extern "C" {
   #error Buildsystem error: BUILDING_FFMPEG not defined
 #endif
 
-#if LIBAVCODEC_VERSION_INT < AV_VERSION_INT(54, 86, 100)
-  #error Minimum supported version of libavcodec is 54.86.100.
+// Minimum supported versions:
+// FFmpeg: 1.1
+// libav: 9.20 (for Ubuntu 14.04)
+#if LIBAVCODEC_VERSION_INT < AV_VERSION_INT(54, 35, 1)
+  #error Minimum supported version of libavcodec is 54.35.1.
 #endif
 
-#if LIBAVFORMAT_VERSION_INT < AV_VERSION_INT(54, 59, 106)
-  #error Minimum supported version of libavformat is 54.59.106.
+#if LIBAVFORMAT_VERSION_INT < AV_VERSION_INT(54, 20, 4)
+  #error Minimum supported version of libavformat is 54.20.4.
 #endif
 
-#if LIBAVUTIL_VERSION_INT < AV_VERSION_INT(52, 13, 100)
-  #error Minimum supported version of libavutil is 52.13.100.
+#if LIBAVUTIL_VERSION_INT < AV_VERSION_INT(52, 3, 0)
+  #error Minimum supported version of libavutil is 52.3.0.
 #endif
 
 ConfigureDef(config_ffmpeg);

From e9ae7dcc407d8198a701b761d0431f456c8ad925 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Mon, 2 Apr 2018 23:16:03 +0200
Subject: [PATCH 02/17] Use vector_uchar instead of string for binary
 network/file data

This distinction allows us to better support Python 3, since it will raise exceptions when trying to put arbitrary binary data in a str object.

This also adds some convenience functions for efficiently initializing a Datagram or PTA_uchar from a vector_uchar.
---
 .../src/distributed/cConnectionRepository.cxx |  6 +-
 dtool/src/prc/encryptStreamBuf.cxx            |  7 ++-
 dtool/src/prc/streamReader.cxx                | 12 ++--
 dtool/src/prc/streamReader.h                  |  3 +-
 panda/src/downloader/downloadDb.cxx           | 55 ++++++----------
 panda/src/downloader/downloadDb.h             |  8 +--
 panda/src/downloader/socketStream.cxx         | 19 +++---
 panda/src/downloader/socketStream.h           |  3 +-
 panda/src/express/datagram.I                  | 62 +++----------------
 panda/src/express/datagram.h                  | 13 +---
 panda/src/express/datagramIterator.I          | 11 ++--
 panda/src/express/datagramIterator.cxx        | 14 ++---
 panda/src/express/datagramIterator.h          |  4 +-
 panda/src/express/hashVal.cxx                 |  6 +-
 panda/src/express/hashVal.h                   |  4 +-
 panda/src/express/multifile.cxx               |  6 +-
 panda/src/express/pointerToArray.I            | 26 ++++++++
 panda/src/express/pointerToArray.h            |  2 +
 panda/src/express/pointerToArrayBase.I        | 10 +++
 panda/src/express/pointerToArrayBase.h        |  1 +
 panda/src/gobj/texture.cxx                    |  4 +-
 panda/src/movies/wavAudioCursor.cxx           | 11 ++--
 panda/src/recorder/socketStreamRecorder.cxx   |  6 +-
 pandatool/src/flt/fltBeadID.cxx               | 12 ++--
 pandatool/src/flt/fltRecord.cxx               |  5 +-
 25 files changed, 143 insertions(+), 167 deletions(-)

diff --git a/direct/src/distributed/cConnectionRepository.cxx b/direct/src/distributed/cConnectionRepository.cxx
index 67d6ec1658..e247c2bd55 100644
--- a/direct/src/distributed/cConnectionRepository.cxx
+++ b/direct/src/distributed/cConnectionRepository.cxx
@@ -803,8 +803,9 @@ handle_update_field_owner() {
       Py_DECREF(dclass_this);
 
       // check if we should forward this update to the owner view
+      vector_uchar data = _di.get_remaining_bytes();
       DCPacker packer;
-      packer.set_unpack_data(_di.get_remaining_bytes());
+      packer.set_unpack_data((const char *)data.data(), data.size(), false);
       int field_id = packer.raw_unpack_uint16();
       DCField *field = dclass->get_field_by_index(field_id);
       if (field->is_ownrecv()) {
@@ -845,8 +846,9 @@ handle_update_field_owner() {
       Py_DECREF(dclass_this);
 
       // check if we should forward this update to the owner view
+      vector_uchar data = _di.get_remaining_bytes();
       DCPacker packer;
-      packer.set_unpack_data(_di.get_remaining_bytes());
+      packer.set_unpack_data((const char *)data.data(), data.size(), false);
       int field_id = packer.raw_unpack_uint16();
       DCField *field = dclass->get_field_by_index(field_id);
       if (true) {//field->is_broadcast()) {
diff --git a/dtool/src/prc/encryptStreamBuf.cxx b/dtool/src/prc/encryptStreamBuf.cxx
index 21a33f93c0..dc38ac5894 100644
--- a/dtool/src/prc/encryptStreamBuf.cxx
+++ b/dtool/src/prc/encryptStreamBuf.cxx
@@ -146,14 +146,15 @@ open_read(istream *source, bool owns_source, const string &password) {
   int iv_length = EVP_CIPHER_iv_length(cipher);
   _read_block_size = EVP_CIPHER_block_size(cipher);
 
-  string iv = sr.extract_bytes(iv_length);
+  unsigned char *iv = (unsigned char *)alloca(iv_length);
+  iv_length = (int)sr.extract_bytes(iv, iv_length);
 
   _read_ctx = EVP_CIPHER_CTX_new();
   nassertv(_read_ctx != NULL);
 
   // Initialize the context
   int result;
-  result = EVP_DecryptInit(_read_ctx, cipher, NULL, (unsigned char *)iv.data());
+  result = EVP_DecryptInit(_read_ctx, cipher, NULL, (unsigned char *)iv);
   nassertv(result > 0);
 
   result = EVP_CIPHER_CTX_set_key_length(_read_ctx, key_length);
@@ -170,7 +171,7 @@ open_read(istream *source, bool owns_source, const string &password) {
   unsigned char *key = (unsigned char *)alloca(key_length);
   result =
     PKCS5_PBKDF2_HMAC_SHA1((const char *)password.data(), password.length(),
-                           (unsigned char *)iv.data(), iv.length(),
+                           iv, iv_length,
                            count * iteration_count_factor + 1,
                            key_length, key);
   nassertv(result > 0);
diff --git a/dtool/src/prc/streamReader.cxx b/dtool/src/prc/streamReader.cxx
index 17252f5dd2..e9fa173ad1 100644
--- a/dtool/src/prc/streamReader.cxx
+++ b/dtool/src/prc/streamReader.cxx
@@ -117,16 +117,18 @@ extract_bytes(unsigned char *into, size_t size) {
  * Extracts the indicated number of bytes in the stream and returns them as a
  * string.  Returns empty string at end-of-file.
  */
-string StreamReader::
+vector_uchar StreamReader::
 extract_bytes(size_t size) {
+  vector_uchar buffer;
   if (_in->eof() || _in->fail()) {
-    return string();
+    return buffer;
   }
 
-  char *buffer = (char *)alloca(size);
-  _in->read(buffer, size);
+  buffer.resize(size);
+  _in->read((char *)&buffer[0], size);
   size_t read_bytes = _in->gcount();
-  return string(buffer, read_bytes);
+  buffer.resize(read_bytes);
+  return buffer;
 }
 
 /**
diff --git a/dtool/src/prc/streamReader.h b/dtool/src/prc/streamReader.h
index bedaa0eeb5..1643dd4a9c 100644
--- a/dtool/src/prc/streamReader.h
+++ b/dtool/src/prc/streamReader.h
@@ -19,6 +19,7 @@
 #include "numeric_types.h"
 #include "littleEndian.h"
 #include "bigEndian.h"
+#include "vector_uchar.h"
 
 /**
  * A class to read sequential binary data directly from an istream.  Its
@@ -71,7 +72,7 @@ PUBLISHED:
   EXTENSION(BLOCKING PyObject *readlines());
 
 public:
-  BLOCKING string extract_bytes(size_t size);
+  BLOCKING vector_uchar extract_bytes(size_t size);
   BLOCKING string readline();
 
 private:
diff --git a/panda/src/downloader/downloadDb.cxx b/panda/src/downloader/downloadDb.cxx
index f2a734af17..a210fba8bd 100644
--- a/panda/src/downloader/downloadDb.cxx
+++ b/panda/src/downloader/downloadDb.cxx
@@ -583,9 +583,7 @@ add_multifile_record(PT(MultifileRecord) mfr) {
  * Verifies magic number, returns the number of multifiles or -1 if invalid
  */
 int DownloadDb::Db::
-parse_header(const string &data) {
-  Datagram dg(data);
-
+parse_header(Datagram dg) {
   // Make sure we have a good header
   DatagramIterator di(dg);
   uint32_t magic_number = di.get_uint32();
@@ -623,8 +621,7 @@ parse_header(const string &data) {
  * record
  */
 int DownloadDb::Db::
-parse_record_header(const string &data) {
-  Datagram dg(data);
+parse_record_header(Datagram dg) {
   DatagramIterator di(dg);
   int32_t record_length = di.get_int32();
   downloader_cat.spam()
@@ -639,14 +636,12 @@ parse_record_header(const string &data) {
  * Parses a multifile record (mfr) and returns one
  */
 PT(DownloadDb::MultifileRecord) DownloadDb::Db::
-parse_mfr(const string &data) {
+parse_mfr(Datagram dg) {
 
   PT(DownloadDb::MultifileRecord) mfr = new DownloadDb::MultifileRecord;
 
-  Datagram dg(data);
   DatagramIterator di(dg);
-  int32_t mfr_name_length = di.get_int32();
-  mfr->_name = di.extract_bytes(mfr_name_length);
+  mfr->_name = di.get_string32();
   mfr->_phase = di.get_float64();
   mfr->_size = di.get_int32();
   mfr->_status = di.get_int32();
@@ -676,14 +671,12 @@ parse_mfr(const string &data) {
  * Parses a file record (fr) and returns one
  */
 PT(DownloadDb::FileRecord) DownloadDb::Db::
-parse_fr(const string &data) {
+parse_fr(Datagram dg) {
 
   PT(DownloadDb::FileRecord) fr = new DownloadDb::FileRecord;
 
-  Datagram dg(data);
   DatagramIterator di(dg);
-  int32_t fr_name_length = di.get_int32();
-  fr->_name = di.extract_bytes(fr_name_length);
+  fr->_name = di.get_string32();
 
   // At one time, we stored files in the database with a backslash separator.
   // Nowadays we use a forward slash, but we should make sure we properly
@@ -706,15 +699,14 @@ parse_fr(const string &data) {
 bool DownloadDb::Db::
 read(StreamReader &sr, bool want_server_info) {
   // Read the header
-  string header;
-  header = sr.extract_bytes(_header_length);
+  vector_uchar header = sr.extract_bytes(_header_length);
   if (header.size() != (size_t)_header_length) {
     downloader_cat.error() << "truncated db file" << endl;
     return false;
   }
 
   // Parse the header
-  int num_multifiles = parse_header(header);
+  int num_multifiles = parse_header(Datagram(move(header)));
   if (num_multifiles < 0) {
     downloader_cat.error() << "invalid db header" << endl;
     return false;
@@ -727,26 +719,26 @@ read(StreamReader &sr, bool want_server_info) {
     // of the record
     int mfr_header_length = sizeof(int32_t);
 
-    string mfr_header = sr.extract_bytes(mfr_header_length);
+    vector_uchar mfr_header = sr.extract_bytes(mfr_header_length);
     if (mfr_header.size() != (size_t)mfr_header_length) {
       downloader_cat.error() << "invalid mfr header" << endl;
       return false;
     }
 
     // Parse the header
-    int mfr_length = parse_record_header(mfr_header);
+    int mfr_length = parse_record_header(Datagram(move(mfr_header)));
 
     // Ok, now that we know the size of the mfr, read it in Make a buffer to
     // read the multifile record into do not count the header length twice
     int read_length = (mfr_length - mfr_header_length);
-    string mfr_record = sr.extract_bytes(read_length);
+    vector_uchar mfr_record = sr.extract_bytes(read_length);
     if (mfr_record.size() != (size_t)read_length) {
       downloader_cat.error() << "invalid mfr record" << endl;
       return false;
     }
 
     // Parse the mfr
-    PT(DownloadDb::MultifileRecord) mfr = parse_mfr(mfr_record);
+    PT(DownloadDb::MultifileRecord) mfr = parse_mfr(Datagram(move(mfr_record)));
 
     // Only read in the individual file info if you are the server
     if (want_server_info) {
@@ -758,27 +750,27 @@ read(StreamReader &sr, bool want_server_info) {
         int fr_header_length = sizeof(int32_t);
 
         // Read the header
-        string fr_header = sr.extract_bytes(fr_header_length);
+        vector_uchar fr_header = sr.extract_bytes(fr_header_length);
         if (fr_header.size() != (size_t)fr_header_length) {
           downloader_cat.error() << "invalid fr header" << endl;
           return false;
         }
 
         // Parse the header
-        int fr_length = parse_record_header(fr_header);
+        int fr_length = parse_record_header(Datagram(move(fr_header)));
 
         // Ok, now that we know the size of the mfr, read it in do not count
         // the header length twice
         int read_length = (fr_length - fr_header_length);
 
-        string fr_record = sr.extract_bytes(read_length);
+        vector_uchar fr_record = sr.extract_bytes(read_length);
         if (fr_record.size() != (size_t)read_length) {
           downloader_cat.error() << "invalid fr record" << endl;
           return false;
         }
 
         // Parse the file record
-        PT(DownloadDb::FileRecord) fr = parse_fr(fr_record);
+        PT(DownloadDb::FileRecord) fr = parse_fr(Datagram(move(fr_record)));
 
         // Add this file record to the current multifilerecord
         mfr->add_file_record(fr);
@@ -900,12 +892,10 @@ write_header(ostream &write_stream) {
   // Write the number of multifiles
   dg.add_int32(get_num_multifiles());
 
-  string msg = dg.get_message();
-
   // Seek back to the beginning of the write stream
   write_stream.seekp(0);
   // Overwrite the old bogus header with the real header
-  write_stream.write(msg.data(), msg.length());
+  write_stream.write((const char *)dg.get_data(), dg.get_length());
   return true;
 }
 
@@ -1100,17 +1090,8 @@ read_version_map(StreamReader &sr) {
 
   for (int i = 0; i < num_entries; i++) {
 
-    // Get the length of the file name
-    int name_length = sr.get_int32();
-    if (sr.get_istream()->fail()) {
-      return false;
-    }
-    downloader_cat.spam()
-      << "DownloadDb::read_version_map() - name length: " << name_length
-      << endl;
-
     // Get the file name
-    string name = sr.extract_bytes(name_length);
+    string name = sr.get_string32();
     downloader_cat.spam()
       << "DownloadDb::read_version_map() - name: " << name << endl;
 
diff --git a/panda/src/downloader/downloadDb.h b/panda/src/downloader/downloadDb.h
index 02adedb3d6..b7f206c3b6 100644
--- a/panda/src/downloader/downloadDb.h
+++ b/panda/src/downloader/downloadDb.h
@@ -171,10 +171,10 @@ public:
     bool multifile_exists(string mfname) const;
     PT(MultifileRecord) get_multifile_record_named(string mfname) const;
     void add_multifile_record(PT(MultifileRecord) mfr);
-    int parse_header(const string &data);
-    int parse_record_header(const string &data);
-    PT(MultifileRecord) parse_mfr(const string &data);
-    PT(FileRecord) parse_fr(const string &data);
+    int parse_header(Datagram dg);
+    int parse_record_header(Datagram dg);
+    PT(MultifileRecord) parse_mfr(Datagram dg);
+    PT(FileRecord) parse_fr(Datagram dg);
     bool read(StreamReader &sr, bool want_server_info);
     bool write(StreamWriter &sw, bool want_server_info);
     Filename _filename;
diff --git a/panda/src/downloader/socketStream.cxx b/panda/src/downloader/socketStream.cxx
index af43847fb5..4e441f8f2b 100644
--- a/panda/src/downloader/socketStream.cxx
+++ b/panda/src/downloader/socketStream.cxx
@@ -50,17 +50,17 @@ SSReader::
 bool SSReader::
 do_receive_datagram(Datagram &dg) {
   if (_tcp_header_size == 0) {
-    _data_expected = _data_so_far.length();
+    _data_expected = _data_so_far.size();
   }
   if (_data_expected == 0) {
     // Read the first two bytes: the datagram length.
-    while ((int)_data_so_far.length() < _tcp_header_size) {
+    while ((int)_data_so_far.size() < _tcp_header_size) {
       int ch = _istream->get();
       if (_istream->eof() || _istream->fail()) {
         _istream->clear();
         return false;
       }
-      _data_so_far += (char)ch;
+      _data_so_far.push_back((unsigned char)ch);
     }
 
     Datagram header(_data_so_far);
@@ -70,7 +70,7 @@ do_receive_datagram(Datagram &dg) {
     } else if (_tcp_header_size == 4) {
       _data_expected = di.get_uint32();
     }
-    _data_so_far = _data_so_far.substr(_tcp_header_size);
+    _data_so_far.erase(_data_so_far.begin(), _data_so_far.begin() + _tcp_header_size);
 
     if (_data_expected == 0) {
       // Empty datagram.
@@ -84,20 +84,19 @@ do_receive_datagram(Datagram &dg) {
   static const size_t buffer_size = 1024;
   char buffer[buffer_size];
 
-  size_t read_count = min(_data_expected - _data_so_far.length(),
-                          buffer_size);
+  size_t read_count = min(_data_expected - _data_so_far.size(), buffer_size);
   _istream->read(buffer, read_count);
   size_t count = _istream->gcount();
   while (count != 0) {
-    _data_so_far.append(buffer, count);
+    _data_so_far.insert(_data_so_far.end(), buffer, buffer + count);
 
-    read_count = min(_data_expected - _data_so_far.length(),
+    read_count = min(_data_expected - _data_so_far.size(),
                      buffer_size);
     _istream->read(buffer, read_count);
     count = _istream->gcount();
   }
 
-  if (_data_so_far.length() < _data_expected) {
+  if (_data_so_far.size() < _data_expected) {
     // Not yet here.  Clear the istream error flag and return false to
     // indicate more coming.
     _istream->clear();
@@ -108,7 +107,7 @@ do_receive_datagram(Datagram &dg) {
   dg.append_data(_data_so_far);
 
   _data_expected = 0;
-  _data_so_far = string();
+  _data_so_far.clear();
 
   return true;
 }
diff --git a/panda/src/downloader/socketStream.h b/panda/src/downloader/socketStream.h
index 36065e42af..84ce907a5e 100644
--- a/panda/src/downloader/socketStream.h
+++ b/panda/src/downloader/socketStream.h
@@ -21,6 +21,7 @@
 #include "pdeque.h"
 #include "typedReferenceCount.h"
 #include "pointerTo.h"
+#include "vector_uchar.h"
 
 // At the present, this module is not compiled if OpenSSL is not available,
 // since the only current use for it is to implement OpenSSL-defined
@@ -54,7 +55,7 @@ private:
 
   istream *_istream;
   size_t _data_expected;
-  string _data_so_far;
+  vector_uchar _data_so_far;
   int _tcp_header_size;
 
 #ifdef SIMULATE_NETWORK_DELAY
diff --git a/panda/src/express/datagram.I b/panda/src/express/datagram.I
index fa6063805b..3bd7812969 100644
--- a/panda/src/express/datagram.I
+++ b/panda/src/express/datagram.I
@@ -42,58 +42,16 @@ Datagram(const void *data, size_t size) :
  * Constructs a datagram from an existing block of data.
  */
 INLINE Datagram::
-Datagram(const string &data) :
+Datagram(vector_uchar data) :
+  _data(move(data)),
 #ifdef STDFLOAT_DOUBLE
   _stdfloat_double(true)
 #else
   _stdfloat_double(false)
 #endif
 {
-  append_data(data);
 }
 
-/**
- *
- */
-INLINE Datagram::
-Datagram(const Datagram &copy) :
-  _data(copy._data),
-  _stdfloat_double(copy._stdfloat_double)
-{
-}
-
-/**
- *
- */
-INLINE void Datagram::
-operator = (const Datagram &copy) {
-  _data = copy._data;
-  _stdfloat_double = copy._stdfloat_double;
-}
-
-#ifdef USE_MOVE_SEMANTICS
-/**
- *
- */
-INLINE Datagram::
-Datagram(Datagram &&from) NOEXCEPT :
-  _data(move(from._data)),
-  _stdfloat_double(from._stdfloat_double)
-{
-}
-#endif  // USE_MOVE_SEMANTICS
-
-#ifdef USE_MOVE_SEMANTICS
-/**
- *
- */
-INLINE void Datagram::
-operator = (Datagram &&from) NOEXCEPT {
-  _data = move(from._data);
-  _stdfloat_double = from._stdfloat_double;
-}
-#endif  // USE_MOVE_SEMANTICS
-
 /**
  * Adds a boolean value to the datagram.
  */
@@ -291,7 +249,7 @@ add_string(const string &str) {
   add_uint16((uint16_t)str.length());
 
   // Add the string
-  append_data(str);
+  append_data(str.data(), str.length());
 }
 
 /**
@@ -304,18 +262,18 @@ add_string32(const string &str) {
   add_uint32((uint32_t)str.length());
 
   // Add the string
-  append_data(str);
+  append_data(str.data(), str.length());
 }
 
 /**
  * Adds a variable-length string to the datagram, as a NULL-terminated string.
  */
 INLINE void Datagram::
-add_z_string(string str) {
+add_z_string(const string &str) {
   // We must not have any nested null characters in the string.
   size_t null_pos = str.find('\0');
   // Add the string (sans the null character).
-  append_data(str.substr(0, null_pos));
+  append_data(str.data(), std::min<size_t>(null_pos, str.length()));
 
   // And the null character.
   add_uint8('\0');
@@ -329,11 +287,11 @@ add_z_string(string str) {
 INLINE void Datagram::
 add_fixed_string(const string &str, size_t size) {
   if (str.length() < size) {
-    append_data(str);
+    append_data(str.data(), str.length());
     pad_bytes(size - str.length());
 
   } else { // str.length() >= size
-    append_data(str.substr(0, size));
+    append_data(str.data(), size);
   }
 }
 
@@ -341,8 +299,8 @@ add_fixed_string(const string &str, size_t size) {
  * Appends some more raw data to the end of the datagram.
  */
 INLINE void Datagram::
-append_data(const string &data) {
-  append_data(data.data(), data.length());
+append_data(const vector_uchar &data) {
+  append_data(data.data(), data.size());
 }
 
 /**
diff --git a/panda/src/express/datagram.h b/panda/src/express/datagram.h
index c2cb3b4c8b..9250ac89d3 100644
--- a/panda/src/express/datagram.h
+++ b/panda/src/express/datagram.h
@@ -39,14 +39,7 @@ class EXPCL_PANDAEXPRESS Datagram : public TypedObject {
 PUBLISHED:
   INLINE Datagram();
   INLINE Datagram(const void *data, size_t size);
-  INLINE Datagram(const string &data);
-  INLINE Datagram(const Datagram &copy);
-  INLINE void operator = (const Datagram &copy);
-
-#ifdef USE_MOVE_SEMANTICS
-  INLINE Datagram(Datagram &&from) NOEXCEPT;
-  INLINE void operator = (Datagram &&from) NOEXCEPT;
-#endif
+  INLINE explicit Datagram(vector_uchar data);
 
   virtual ~Datagram();
 
@@ -80,13 +73,13 @@ PUBLISHED:
 
   INLINE void add_string(const string &str);
   INLINE void add_string32(const string &str);
-  INLINE void add_z_string(string str);
+  INLINE void add_z_string(const string &str);
   INLINE void add_fixed_string(const string &str, size_t size);
   void add_wstring(const wstring &str);
 
   void pad_bytes(size_t size);
   void append_data(const void *data, size_t size);
-  INLINE void append_data(const string &data);
+  INLINE void append_data(const vector_uchar &data);
 
   void assign(const void *data, size_t size);
 
diff --git a/panda/src/express/datagramIterator.I b/panda/src/express/datagramIterator.I
index cefde399f2..42c25eeed4 100644
--- a/panda/src/express/datagramIterator.I
+++ b/panda/src/express/datagramIterator.I
@@ -422,14 +422,13 @@ skip_bytes(size_t size) {
  * Returns the remaining bytes in the datagram as a string, but does not
  * extract them from the iterator.
  */
-INLINE string DatagramIterator::
+INLINE vector_uchar DatagramIterator::
 get_remaining_bytes() const {
-  nassertr(_datagram != (const Datagram *)NULL, "");
-  nassertr(_current_index <= _datagram->get_length(), "");
+  nassertr(_datagram != (const Datagram *)NULL, vector_uchar());
+  nassertr(_current_index <= _datagram->get_length(), vector_uchar());
 
-  const char *ptr = (const char *)_datagram->get_data();
-  size_t remaining_size = _datagram->get_length() - _current_index;
-  return string(ptr + _current_index, remaining_size);
+  const unsigned char *ptr = (const unsigned char *)_datagram->get_data();
+  return vector_uchar(ptr + _current_index, ptr + _datagram->get_length());
 }
 
 /**
diff --git a/panda/src/express/datagramIterator.cxx b/panda/src/express/datagramIterator.cxx
index 22ac9ecb19..880719f32b 100644
--- a/panda/src/express/datagramIterator.cxx
+++ b/panda/src/express/datagramIterator.cxx
@@ -119,18 +119,18 @@ get_wstring() {
  * Extracts the indicated number of bytes in the datagram and returns them as
  * a string.
  */
-string DatagramIterator::
+vector_uchar DatagramIterator::
 extract_bytes(size_t size) {
-  nassertr((int)size >= 0, "");
-  nassertr(_datagram != (const Datagram *)NULL, "");
-  nassertr(_current_index + size <= _datagram->get_length(), "");
+  nassertr((int)size >= 0, vector_uchar());
+  nassertr(_datagram != (const Datagram *)NULL, vector_uchar());
+  nassertr(_current_index + size <= _datagram->get_length(), vector_uchar());
 
-  const char *ptr = (const char *)_datagram->get_data();
-  size_t last_index = _current_index;
+  const unsigned char *ptr = (const unsigned char *)_datagram->get_data();
+  ptr += _current_index;
 
   _current_index += size;
 
-  return string(ptr + last_index, size);
+  return vector_uchar(ptr, ptr + size);
 }
 
 /**
diff --git a/panda/src/express/datagramIterator.h b/panda/src/express/datagramIterator.h
index 7126901324..ec76be3f07 100644
--- a/panda/src/express/datagramIterator.h
+++ b/panda/src/express/datagramIterator.h
@@ -62,10 +62,10 @@ PUBLISHED:
   wstring get_wstring();
 
   INLINE void skip_bytes(size_t size);
-  string extract_bytes(size_t size);
+  vector_uchar extract_bytes(size_t size);
   size_t extract_bytes(unsigned char *into, size_t size);
 
-  INLINE string get_remaining_bytes() const;
+  INLINE vector_uchar get_remaining_bytes() const;
   INLINE size_t get_remaining_size() const;
 
   INLINE const Datagram &get_datagram() const;
diff --git a/panda/src/express/hashVal.cxx b/panda/src/express/hashVal.cxx
index 7d52dc5a5e..aa08714668 100644
--- a/panda/src/express/hashVal.cxx
+++ b/panda/src/express/hashVal.cxx
@@ -143,11 +143,11 @@ set_from_hex(const string &text) {
 /**
  * Returns the HashVal as a 16-byte binary string.
  */
-string HashVal::
+vector_uchar HashVal::
 as_bin() const {
   Datagram dg;
   write_datagram(dg);
-  return dg.get_message();
+  return vector_uchar((unsigned char *)dg.get_data(), (unsigned char *)dg.get_data() + dg.get_length());
 }
 
 /**
@@ -155,7 +155,7 @@ as_bin() const {
  * false otherwise.
  */
 bool HashVal::
-set_from_bin(const string &text) {
+set_from_bin(const vector_uchar &text) {
   nassertr(text.size() == 16, false);
   Datagram dg(text);
   DatagramIterator dgi(dg);
diff --git a/panda/src/express/hashVal.h b/panda/src/express/hashVal.h
index d0652d1e01..a4b3754614 100644
--- a/panda/src/express/hashVal.h
+++ b/panda/src/express/hashVal.h
@@ -55,8 +55,8 @@ PUBLISHED:
   string as_hex() const;
   bool set_from_hex(const string &text);
 
-  string as_bin() const;
-  bool set_from_bin(const string &text);
+  vector_uchar as_bin() const;
+  bool set_from_bin(const vector_uchar &text);
 
   INLINE void write_datagram(Datagram &destination) const;
   INLINE void read_datagram(DatagramIterator &source);
diff --git a/panda/src/express/multifile.cxx b/panda/src/express/multifile.cxx
index 0d98849efe..5a7d86f17b 100644
--- a/panda/src/express/multifile.cxx
+++ b/panda/src/express/multifile.cxx
@@ -2402,7 +2402,7 @@ check_signatures() {
     nassertv(stream != NULL);
     StreamReader reader(*stream);
     size_t sig_size = reader.get_uint32();
-    string sig_string = reader.extract_bytes(sig_size);
+    vector_uchar sig_data = reader.extract_bytes(sig_size);
 
     size_t num_certs = reader.get_uint32();
 
@@ -2470,9 +2470,7 @@ check_signatures() {
 
       // Now check that the signature matches the hash.
       int verify_result =
-        EVP_VerifyFinal(md_ctx,
-                        (unsigned char *)sig_string.data(),
-                        sig_string.size(), pkey);
+        EVP_VerifyFinal(md_ctx, sig_data.data(), sig_data.size(), pkey);
       if (verify_result == 1) {
         // The signature matches; save the certificate and its chain.
         _signatures.push_back(chain);
diff --git a/panda/src/express/pointerToArray.I b/panda/src/express/pointerToArray.I
index c3a10f3737..535de63d01 100644
--- a/panda/src/express/pointerToArray.I
+++ b/panda/src/express/pointerToArray.I
@@ -92,6 +92,19 @@ PointerToArray(PointerToArray<Element> &&from) NOEXCEPT :
 }
 #endif  // USE_MOVE_SEMANTICS
 
+#ifdef USE_MOVE_SEMANTICS
+/**
+ * Initializes the PTA from a vector.
+ */
+template<class Element>
+INLINE PointerToArray<Element>::
+PointerToArray(pvector<Element> &&from, TypeHandle type_handle) :
+  PointerToArrayBase<Element>(new ReferenceCountedVector<Element>(move(from))),
+  _type_handle(type_handle)
+{
+}
+#endif  // USE_MOVE_SEMANTICS
+
 /**
  *
  */
@@ -710,6 +723,19 @@ ConstPointerToArray(ConstPointerToArray<Element> &&from) NOEXCEPT :
 }
 #endif  // USE_MOVE_SEMANTICS
 
+#ifdef USE_MOVE_SEMANTICS
+/**
+ * Initializes the PTA from a vector.
+ */
+template<class Element>
+INLINE ConstPointerToArray<Element>::
+ConstPointerToArray(pvector<Element> &&from, TypeHandle type_handle) :
+  PointerToArrayBase<Element>(new ReferenceCountedVector<Element>(move(from))),
+  _type_handle(type_handle)
+{
+}
+#endif  // USE_MOVE_SEMANTICS
+
 /**
  *
  */
diff --git a/panda/src/express/pointerToArray.h b/panda/src/express/pointerToArray.h
index 762a6cb8ce..4e8a052e0f 100644
--- a/panda/src/express/pointerToArray.h
+++ b/panda/src/express/pointerToArray.h
@@ -141,6 +141,7 @@ public:
 
 #ifdef USE_MOVE_SEMANTICS
   INLINE PointerToArray(PointerToArray<Element> &&from) NOEXCEPT;
+  INLINE explicit PointerToArray(pvector<Element> &&from, TypeHandle type_handle = get_type_handle(Element));
 #endif
 
 public:
@@ -302,6 +303,7 @@ PUBLISHED:
 #ifdef USE_MOVE_SEMANTICS
   INLINE ConstPointerToArray(PointerToArray<Element> &&from) NOEXCEPT;
   INLINE ConstPointerToArray(ConstPointerToArray<Element> &&from) NOEXCEPT;
+  INLINE explicit ConstPointerToArray(pvector<Element> &&from, TypeHandle type_handle = get_type_handle(Element));
 #endif
 
   // Duplicating the interface of vector.
diff --git a/panda/src/express/pointerToArrayBase.I b/panda/src/express/pointerToArrayBase.I
index 89acba1206..de8c17d843 100644
--- a/panda/src/express/pointerToArrayBase.I
+++ b/panda/src/express/pointerToArrayBase.I
@@ -39,6 +39,16 @@ ReferenceCountedVector(const Element *begin, const Element *end, TypeHandle type
 {
 }
 
+/**
+ * Creates an array that takes its elements from the given vector.
+ */
+template<class Element>
+INLINE ReferenceCountedVector<Element>::
+ReferenceCountedVector(pvector<Element> &&from) :
+  pvector<Element>(move(from))
+{
+}
+
 /**
  *
  */
diff --git a/panda/src/express/pointerToArrayBase.h b/panda/src/express/pointerToArrayBase.h
index 3220ca4c70..8c33f69be2 100644
--- a/panda/src/express/pointerToArrayBase.h
+++ b/panda/src/express/pointerToArrayBase.h
@@ -43,6 +43,7 @@ public:
   INLINE ReferenceCountedVector(TypeHandle type_handle);
   INLINE ReferenceCountedVector(size_type initial_size, TypeHandle type_handle);
   INLINE ReferenceCountedVector(const Element *begin, const Element *end, TypeHandle type_handle);
+  INLINE ReferenceCountedVector(pvector<Element> &&from);
   ALLOC_DELETED_CHAIN(ReferenceCountedVector<Element>);
 
   INLINE size_type size() const;
diff --git a/panda/src/gobj/texture.cxx b/panda/src/gobj/texture.cxx
index c4a8149ab4..5328b921d9 100644
--- a/panda/src/gobj/texture.cxx
+++ b/panda/src/gobj/texture.cxx
@@ -4207,7 +4207,9 @@ bool Texture::
 do_read_ktx(CData *cdata, istream &in, const string &filename, bool header_only) {
   StreamReader ktx(in);
 
-  if (ktx.extract_bytes(12) != "\xABKTX 11\xBB\r\n\x1A\n") {
+  unsigned char magic[12];
+  if (ktx.extract_bytes(magic, 12) != 12 ||
+      memcmp(magic, "\xABKTX 11\xBB\r\n\x1A\n", 12) != 0) {
     gobj_cat.error()
       << filename << " is not a KTX file.\n";
     return false;
diff --git a/panda/src/movies/wavAudioCursor.cxx b/panda/src/movies/wavAudioCursor.cxx
index 3b220749c4..ccfaa9733e 100644
--- a/panda/src/movies/wavAudioCursor.cxx
+++ b/panda/src/movies/wavAudioCursor.cxx
@@ -106,7 +106,8 @@ WavAudioCursor(WavAudio *src, istream *stream) :
   nassertv(stream != NULL);
 
   // Beginning of "RIFF" chunk.
-  if (_reader.extract_bytes(4) != "RIFF") {
+  unsigned char magic[4];
+  if (_reader.extract_bytes(magic, 4) != 4 || memcmp(magic, "RIFF", 4) != 0) {
     movies_cat.error()
       << ".wav file is not a valid RIFF file.\n";
     return;
@@ -114,7 +115,7 @@ WavAudioCursor(WavAudio *src, istream *stream) :
 
   unsigned int chunk_size = _reader.get_uint32();
 
-  if (_reader.extract_bytes(4) != "WAVE") {
+  if (_reader.extract_bytes(magic, 4) != 4 || memcmp(magic, "WAVE", 4) != 0) {
     movies_cat.error()
       << ".wav file is a RIFF file but does not start with a WAVE chunk.\n";
     return;
@@ -126,10 +127,10 @@ WavAudioCursor(WavAudio *src, istream *stream) :
 
   while ((!have_fmt || !have_data) && _stream->good() && (bytes_read + 8) < chunk_size) {
 
-    string subchunk_id = _reader.extract_bytes(4);
+    _reader.extract_bytes(magic, 4);
     unsigned int subchunk_size = _reader.get_uint32();
 
-    if (subchunk_id == "fmt ") {
+    if (memcmp(magic, "fmt ", 4) == 0) {
       // The format chunk specifies information about the storage.
       nassertv(subchunk_size >= 16);
       have_fmt = true;
@@ -202,7 +203,7 @@ WavAudioCursor(WavAudio *src, istream *stream) :
         _reader.skip_bytes(subchunk_size - read_bytes);
       }
 
-    } else if (subchunk_id == "data") {
+    } else if (memcmp(magic, "data", 4) == 0) {
       // The data chunk contains the actual sammples.
       if (!have_fmt) {
         movies_cat.error()
diff --git a/panda/src/recorder/socketStreamRecorder.cxx b/panda/src/recorder/socketStreamRecorder.cxx
index 1b9493fc03..6209239044 100644
--- a/panda/src/recorder/socketStreamRecorder.cxx
+++ b/panda/src/recorder/socketStreamRecorder.cxx
@@ -82,8 +82,10 @@ play_frame(DatagramIterator &scan, BamReader *manager) {
 
   int num_packets = scan.get_uint16();
   for (int i = 0; i < num_packets; i++) {
-    string packet = scan.get_string();
-    _data.push_back(Datagram(packet));
+    size_t size = scan.get_uint16();
+    vector_uchar packet(size);
+    scan.extract_bytes(&packet[0], size);
+    _data.push_back(Datagram(move(packet)));
   }
 }
 
diff --git a/pandatool/src/flt/fltBeadID.cxx b/pandatool/src/flt/fltBeadID.cxx
index 6346d6282e..f55d3e88cc 100644
--- a/pandatool/src/flt/fltBeadID.cxx
+++ b/pandatool/src/flt/fltBeadID.cxx
@@ -78,9 +78,8 @@ extract_record(FltRecordReader &reader) {
 bool FltBeadID::
 extract_ancillary(FltRecordReader &reader) {
   if (reader.get_opcode() == FO_long_id) {
-    string s = reader.get_iterator().get_remaining_bytes();
-    size_t zero_byte = s.find('\0');
-    _id = s.substr(0, zero_byte);
+    vector_uchar s = reader.get_iterator().get_remaining_bytes();
+    _id.assign((const char *)s.data(), strnlen((const char *)s.data(), s.size()));
     return true;
   }
 
@@ -109,14 +108,11 @@ build_record(FltRecordWriter &writer) const {
 FltError FltBeadID::
 write_ancillary(FltRecordWriter &writer) const {
   if (_id.length() > 7) {
+    Datagram dc;
 
     // Although the manual mentions nothing of this, it is essential that the
     // length of the record be a multiple of 4 bytes.
-    string id = _id;
-    while ((id.length() % 4) != 0) {
-      id += '\0';
-    }
-    Datagram dc(id);
+    dc.add_fixed_string(_id, (_id.length() + 3) & ~3);
 
     FltError result = writer.write_record(FO_long_id, dc);
     if (result != FE_ok) {
diff --git a/pandatool/src/flt/fltRecord.cxx b/pandatool/src/flt/fltRecord.cxx
index c3dc21d070..a0af83e180 100644
--- a/pandatool/src/flt/fltRecord.cxx
+++ b/pandatool/src/flt/fltRecord.cxx
@@ -621,7 +621,8 @@ extract_record(FltRecordReader &) {
 bool FltRecord::
 extract_ancillary(FltRecordReader &reader) {
   if (reader.get_opcode() == FO_comment) {
-    _comment = reader.get_iterator().get_remaining_bytes();
+    vector_uchar s = reader.get_iterator().get_remaining_bytes();
+    _comment.assign((const char *)s.data(), strnlen((const char *)s.data(), s.size()));
     return true;
   }
 
@@ -735,7 +736,7 @@ build_record(FltRecordWriter &) const {
 FltError FltRecord::
 write_ancillary(FltRecordWriter &writer) const {
   if (!_comment.empty()) {
-    Datagram dc(_comment);
+    Datagram dc(_comment.data(), _comment.size());
     FltError result = writer.write_record(FO_comment, dc);
     if (result != FE_ok) {
       return result;

From 7cbdd3b6c49312b90489ba7ebfce5b2b0f22910b Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Wed, 4 Apr 2018 21:36:10 +0200
Subject: [PATCH 03/17] gobj: release GIL for (un)compress_ram_image

---
 panda/src/gobj/texture.h | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/panda/src/gobj/texture.h b/panda/src/gobj/texture.h
index 5816b8c538..890710a216 100644
--- a/panda/src/gobj/texture.h
+++ b/panda/src/gobj/texture.h
@@ -464,10 +464,10 @@ PUBLISHED:
   MAKE_PROPERTY(keep_ram_image, get_keep_ram_image, set_keep_ram_image);
   MAKE_PROPERTY(cacheable, is_cacheable);
 
-  INLINE bool compress_ram_image(CompressionMode compression = CM_on,
-                                 QualityLevel quality_level = QL_default,
-                                 GraphicsStateGuardianBase *gsg = NULL);
-  INLINE bool uncompress_ram_image();
+  BLOCKING INLINE bool compress_ram_image(CompressionMode compression = CM_on,
+                                          QualityLevel quality_level = QL_default,
+                                          GraphicsStateGuardianBase *gsg = NULL);
+  BLOCKING INLINE bool uncompress_ram_image();
 
   INLINE int get_num_ram_mipmap_images() const;
   INLINE bool has_ram_mipmap_image(int n) const;

From 94476fd1f0e402a237f1b4cf5d77347a7ec4f682 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Wed, 4 Apr 2018 21:46:01 +0200
Subject: [PATCH 04/17] glgsg: fix invalid operation error with multisample FBO

Panda is forgetting to reset the current FBO when resolving multisamples.
---
 panda/src/glstuff/glGraphicsBuffer_src.cxx | 1 +
 1 file changed, 1 insertion(+)

diff --git a/panda/src/glstuff/glGraphicsBuffer_src.cxx b/panda/src/glstuff/glGraphicsBuffer_src.cxx
index 43f3dbd809..35daa0b225 100644
--- a/panda/src/glstuff/glGraphicsBuffer_src.cxx
+++ b/panda/src/glstuff/glGraphicsBuffer_src.cxx
@@ -1767,6 +1767,7 @@ resolve_multisamples() {
   }
   glgsg->_glBindFramebuffer(GL_DRAW_FRAMEBUFFER_EXT, fbo);
   glgsg->_glBindFramebuffer(GL_READ_FRAMEBUFFER_EXT, _fbo_multisample);
+  glgsg->_current_fbo = fbo;
 
   // If the depth buffer is shared, resolve it only on the last to render FBO.
   bool do_depth_blit = false;

From 552a649ef3fcad1690f99e53b1d50e7494bce21c Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Wed, 4 Apr 2018 21:48:02 +0200
Subject: [PATCH 05/17] interrogate: add back NULL definition, fixes some
 keyword arguments

I am not sure why the definition of NULL was removed; it might have been by mistake, but in any case it broke code like this:

    img = PNMImage(w, h, color_space=CS_srgb)

since it would not understand the default value (NULL) for the argument preceding color_space.
---
 dtool/src/parser-inc/stdtypedefs.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/dtool/src/parser-inc/stdtypedefs.h b/dtool/src/parser-inc/stdtypedefs.h
index c1febd3955..f971d7e1f2 100644
--- a/dtool/src/parser-inc/stdtypedefs.h
+++ b/dtool/src/parser-inc/stdtypedefs.h
@@ -41,6 +41,11 @@ inline namespace std {
 
 struct timeval;
 
+#ifdef __cplusplus
+#define NULL 0L
+#else
+#define NULL ((void *)0)
+#endif
 typedef decltype(nullptr) nullptr_t;
 
 // One day, we might extend interrogate to be able to parse this,

From 7125a3e5877edc056b6e076285b54f3869dce9f6 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Thu, 5 Apr 2018 20:49:13 +0200
Subject: [PATCH 06/17] interrogate: allow passing None for args that have NULL
 as default value

---
 .../interfaceMakerPythonNative.cxx            | 64 ++++++++++++++++---
 1 file changed, 56 insertions(+), 8 deletions(-)

diff --git a/dtool/src/interrogate/interfaceMakerPythonNative.cxx b/dtool/src/interrogate/interfaceMakerPythonNative.cxx
index 96420ef663..5ae2d3fca9 100644
--- a/dtool/src/interrogate/interfaceMakerPythonNative.cxx
+++ b/dtool/src/interrogate/interfaceMakerPythonNative.cxx
@@ -5414,6 +5414,18 @@ write_function_instance(ostream &out, FunctionRemap *remap,
         parameter_list += ", &" + param_name;
       }
 
+      // If the default value is NULL, we also accept a None value.
+      bool maybe_none = false;
+      if (default_value != nullptr && (return_flags & RF_coerced) == 0) {
+        CPPExpression::Result res = param->get_default_value()->evaluate();
+        if (res._type == CPPExpression::RT_integer ||
+            res._type == CPPExpression::RT_pointer) {
+          if (res.as_integer() == 0) {
+            maybe_none = true;
+          }
+        }
+      }
+
       string class_name = obj_type->get_local_name(&parser);
 
       // need to a forward scope for this class..
@@ -5464,17 +5476,27 @@ write_function_instance(ostream &out, FunctionRemap *remap,
 
           type->output_instance(extra_convert, param_name + "_this", &parser);
 
-          if (is_optional) {
+          if (is_optional && maybe_none) {
+            extra_convert
+              << default_expr << ";\n"
+              << "if (" << param_name << " != NULL && " << param_name << " != Py_None) {\n"
+              << "  " << param_name << "_this";
+          } else if (is_optional) {
             extra_convert
               << default_expr << ";\n"
               << "if (" << param_name << " != NULL) {\n"
               << "  " << param_name << "_this";
+          } else if (maybe_none) {
+            extra_convert
+              << " = NULL;\n"
+              << "if (" << param_name << " != Py_None) {\n"
+              << "  " << param_name << "_this";
           }
 
           extra_convert << " = Dtool_Coerce_" + make_safe_name(class_name) +
             "(" + param_name + ", " + param_name + "_local);\n";
 
-          if (is_optional) {
+          if (is_optional || maybe_none) {
             extra_convert << "}\n";
           }
 
@@ -5485,8 +5507,12 @@ write_function_instance(ostream &out, FunctionRemap *remap,
 
         if (report_errors) {
           // We were asked to report any errors.  Let's do it.
-          if (is_optional) {
+          if (is_optional && maybe_none) {
+            extra_convert << "if (" << param_name << " != NULL && " << param_name << " != Py_None && !" << coerce_call << ") {\n";
+          } else if (is_optional) {
             extra_convert << "if (" << param_name << " != NULL && !" << coerce_call << ") {\n";
+          } else if (maybe_none) {
+            extra_convert << "if (" << param_name << " != Py_None && !" << coerce_call << ") {\n";
           } else {
             extra_convert << "if (!" << coerce_call << ") {\n";
           }
@@ -5509,19 +5535,35 @@ write_function_instance(ostream &out, FunctionRemap *remap,
           }
           extra_convert << "}\n";
 
+        } else if (is_optional && maybe_none) {
+          extra_param_check << " && (" << param_name << " == NULL || " << param_name << " == Py_None || " << coerce_call << ")";
+
         } else if (is_optional) {
           extra_param_check << " && (" << param_name << " == NULL || " << coerce_call << ")";
 
+        } else if (maybe_none) {
+          extra_param_check << " && (" << param_name << " == Py_None || " << coerce_call << ")";
+
         } else {
           extra_param_check << " && " << coerce_call;
         }
 
-      } else {
+      } else { // The regular, non-coercion case.
         type->output_instance(extra_convert, param_name + "_this", &parser);
-        if (is_optional) {
+        if (is_optional && maybe_none) {
           extra_convert
             << default_expr << ";\n"
-            << "if (" << param_name << " != (PyObject *)NULL) {\n"
+            << "if (" << param_name << " != NULL && " << param_name << " != Py_None) {\n"
+            << "  " << param_name << "_this";
+        } else if (is_optional) {
+          extra_convert
+            << default_expr << ";\n"
+            << "if (" << param_name << " != NULL) {\n"
+            << "  " << param_name << "_this";
+        } else if (maybe_none) {
+          extra_convert
+            << " = NULL;\n"
+            << "if (" << param_name << " != Py_None) {\n"
             << "  " << param_name << "_this";
         }
         if (const_ok && !report_errors) {
@@ -5529,7 +5571,7 @@ write_function_instance(ostream &out, FunctionRemap *remap,
           // simpler.  But maybe we should just reorganize these functions
           // entirely?
           extra_convert << " = NULL;\n";
-          int indent_level = is_optional ? 2 : 0;
+          int indent_level = (is_optional || maybe_none) ? 2 : 0;
           indent(extra_convert, indent_level)
             << "DtoolInstance_GetPointer(" << param_name
             << ", " << param_name << "_this"
@@ -5545,9 +5587,15 @@ write_function_instance(ostream &out, FunctionRemap *remap,
             << "\", " << const_ok << ", " << report_errors << ");\n";
         }
 
-        if (is_optional) {
+        if (is_optional && maybe_none) {
+          extra_convert << "}\n";
+          extra_param_check << " && (" << param_name << " == NULL || " << param_name << " == Py_None || " << param_name << "_this != NULL)";
+        } else if (is_optional) {
           extra_convert << "}\n";
           extra_param_check << " && (" << param_name << " == NULL || " << param_name << "_this != NULL)";
+        } else if (maybe_none) {
+          extra_convert << "}\n";
+          extra_param_check << " && (" << param_name << " == Py_None || " << param_name << "_this != NULL)";
         } else {
           extra_param_check << " && " << param_name << "_this != NULL";
         }

From de6d753f79886ab45d8c3cec6b231d15afe64d94 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Fri, 6 Apr 2018 17:16:18 +0200
Subject: [PATCH 07/17] net: don't use get_message() when constructing datagram
 header

This is causing an unnecessary copy operation.
---
 panda/src/net/datagramTCPHeader.cxx | 13 ++++++-------
 panda/src/net/datagramUDPHeader.cxx | 15 ++++++++-------
 2 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/panda/src/net/datagramTCPHeader.cxx b/panda/src/net/datagramTCPHeader.cxx
index 533e3e671b..bd013f0c33 100644
--- a/panda/src/net/datagramTCPHeader.cxx
+++ b/panda/src/net/datagramTCPHeader.cxx
@@ -24,23 +24,23 @@
  */
 DatagramTCPHeader::
 DatagramTCPHeader(const NetDatagram &datagram, int header_size) {
-  const string &str = datagram.get_message();
+  size_t length = datagram.get_length();
   switch (header_size) {
   case 0:
     break;
 
   case datagram_tcp16_header_size:
     {
-      uint16_t size = str.length();
-      nassertv(size == str.length());
+      uint16_t size = (uint16_t)length;
+      nassertv((size_t)size == length);
       _header.add_uint16(size);
     }
     break;
 
   case datagram_tcp32_header_size:
     {
-      uint32_t size = str.length();
-      nassertv(size == str.length());
+      uint32_t size = (uint32_t)length;
+      nassertv((size_t)size == length);
       _header.add_uint32(size);
     }
     break;
@@ -93,8 +93,7 @@ verify_datagram(const NetDatagram &datagram, int header_size) const {
     return true;
   }
 
-  const string &str = datagram.get_message();
-  int actual_size = str.length();
+  int actual_size = (int)datagram.get_length();
   int expected_size = get_datagram_size(header_size);
   if (actual_size == expected_size) {
     return true;
diff --git a/panda/src/net/datagramUDPHeader.cxx b/panda/src/net/datagramUDPHeader.cxx
index b491190187..2191c0241a 100644
--- a/panda/src/net/datagramUDPHeader.cxx
+++ b/panda/src/net/datagramUDPHeader.cxx
@@ -24,10 +24,11 @@
  */
 DatagramUDPHeader::
 DatagramUDPHeader(const NetDatagram &datagram) {
-  const string &str = datagram.get_message();
+  const unsigned char *begin = (const unsigned char *)datagram.get_data();
+  const unsigned char *end = begin + datagram.get_length();
   uint16_t checksum = 0;
-  for (size_t p = 0; p < str.size(); p++) {
-    checksum += (uint16_t)(uint8_t)str[p];
+  for (const unsigned char *p = begin; p != end; ++p) {
+    checksum += (uint16_t)(uint8_t)*p;
   }
 
   // Now pack the header.
@@ -49,11 +50,11 @@ DatagramUDPHeader(const void *data) : _header(data, datagram_udp_header_size) {
  */
 bool DatagramUDPHeader::
 verify_datagram(const NetDatagram &datagram) const {
-  const string &str = datagram.get_message();
-
+  const unsigned char *begin = (const unsigned char *)datagram.get_data();
+  const unsigned char *end = begin + datagram.get_length();
   uint16_t checksum = 0;
-  for (size_t p = 0; p < str.size(); p++) {
-    checksum += (uint16_t)(uint8_t)str[p];
+  for (const unsigned char *p = begin; p != end; ++p) {
+    checksum += (uint16_t)(uint8_t)*p;
   }
 
   if (checksum == get_datagram_checksum()) {

From b4d29e609657e15a807da4832aaed20373b5ab26 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Fri, 6 Apr 2018 17:41:12 +0200
Subject: [PATCH 08/17] express: allow using bytes() on Datagram

Closes: #297
---
 panda/src/express/datagram.I | 12 ++++++++++++
 panda/src/express/datagram.h |  1 +
 tests/putil/test_datagram.py | 10 ++++++++++
 3 files changed, 23 insertions(+)

diff --git a/panda/src/express/datagram.I b/panda/src/express/datagram.I
index 3bd7812969..499bfab48b 100644
--- a/panda/src/express/datagram.I
+++ b/panda/src/express/datagram.I
@@ -316,6 +316,18 @@ get_message() const {
   }
 }
 
+/**
+ * Returns the datagram's data as a bytes object.
+ */
+INLINE vector_uchar Datagram::
+__bytes__() const {
+  if (!_data.empty()) {
+    return vector_uchar(_data.v());
+  } else {
+    return vector_uchar();
+  }
+}
+
 /**
  * Returns a pointer to the beginning of the datagram's data.
  */
diff --git a/panda/src/express/datagram.h b/panda/src/express/datagram.h
index 9250ac89d3..00a46ef36f 100644
--- a/panda/src/express/datagram.h
+++ b/panda/src/express/datagram.h
@@ -84,6 +84,7 @@ PUBLISHED:
   void assign(const void *data, size_t size);
 
   INLINE string get_message() const;
+  INLINE vector_uchar __bytes__() const;
   INLINE const void *get_data() const;
   INLINE size_t get_length() const;
 
diff --git a/tests/putil/test_datagram.py b/tests/putil/test_datagram.py
index 4a34bc88a2..ceadff67b8 100644
--- a/tests/putil/test_datagram.py
+++ b/tests/putil/test_datagram.py
@@ -76,6 +76,16 @@ def datagram_large():
 
     return dg, readback_function
 
+def test_datagram_bytes():
+    """Tests that we can put and get a bytes object on Datagram."""
+    dg = core.Datagram(b'abc\x00')
+    dg.append_data(b'\xff123')
+    assert bytes(dg) == b'abc\x00\xff123'
+
+    dgi = core.DatagramIterator(dg)
+    dgi.get_remaining_bytes() == b'abc\x00\xff123'
+
+
 def test_iterator(datagram_small):
     """This tests Datagram/DatagramIterator, and sort of serves as a self-check
     of the test fixtures too."""

From 22f933a41970e285d6abc4fd6c5d19e50fd423de Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Fri, 6 Apr 2018 20:34:48 +0200
Subject: [PATCH 09/17] tests: disable datagram bytes() test on Python 2

See #297
---
 tests/putil/test_datagram.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/tests/putil/test_datagram.py b/tests/putil/test_datagram.py
index ceadff67b8..1349bd5656 100644
--- a/tests/putil/test_datagram.py
+++ b/tests/putil/test_datagram.py
@@ -1,5 +1,6 @@
 import pytest
 from panda3d import core
+import sys
 
 # Fixtures for generating interesting datagrams (and verification functions) on
 # the fly...
@@ -76,6 +77,7 @@ def datagram_large():
 
     return dg, readback_function
 
+@pytest.mark.skipif(sys.version_info < (3, 0), reason="Requires Python 3")
 def test_datagram_bytes():
     """Tests that we can put and get a bytes object on Datagram."""
     dg = core.Datagram(b'abc\x00')

From d13464104c19be8cb5c41390a6db4aab58ca0817 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Fri, 6 Apr 2018 20:49:43 +0200
Subject: [PATCH 10/17] Fix compilation issue with --nothing on MSVC

I have no idea why this error happens, but it does not seem worth the effort to investigate further, so I'm just reverting the previous change to this file.
---
 dtool/src/dtoolbase/pvector.h | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/dtool/src/dtoolbase/pvector.h b/dtool/src/dtoolbase/pvector.h
index b146947543..14bd542f37 100644
--- a/dtool/src/dtoolbase/pvector.h
+++ b/dtool/src/dtoolbase/pvector.h
@@ -46,9 +46,24 @@ public:
   typedef TYPENAME base_class::size_type size_type;
 
   explicit pvector(TypeHandle type_handle = pvector_type_handle) : base_class(allocator(type_handle)) { }
+  pvector(const pvector<Type> &copy) : base_class(copy) { }
   explicit pvector(size_type n, TypeHandle type_handle = pvector_type_handle) : base_class(n, Type(), allocator(type_handle)) { }
   explicit pvector(size_type n, const Type &value, TypeHandle type_handle = pvector_type_handle) : base_class(n, value, allocator(type_handle)) { }
   pvector(const Type *begin, const Type *end, TypeHandle type_handle = pvector_type_handle) : base_class(begin, end, allocator(type_handle)) { }
+
+#ifdef USE_MOVE_SEMANTICS
+  pvector(pvector<Type> &&from) NOEXCEPT : base_class(move(from)) {};
+
+  pvector<Type> &operator =(pvector<Type> &&from) NOEXCEPT {
+    base_class::operator =(move(from));
+    return *this;
+  }
+#endif
+
+  pvector<Type> &operator =(const pvector<Type> &copy) {
+    base_class::operator =(copy);
+    return *this;
+  }
 };
 
 #endif  // USE_STL_ALLOCATOR

From 753ae3974079ec54a49315381cecc091f25692ff Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Sun, 8 Apr 2018 13:50:33 +0200
Subject: [PATCH 11/17] readme: use MSVC 2015 instead of 2010 (see #288)

[skip ci]
---
 README.md | 22 ++++++++++++----------
 1 file changed, 12 insertions(+), 10 deletions(-)

diff --git a/README.md b/README.md
index fde01c38f0..cf45f0dfd2 100644
--- a/README.md
+++ b/README.md
@@ -43,24 +43,26 @@ Building Panda3D
 Windows
 -------
 
-We currently build using the Microsoft Visual C++ 2010 compiler.  You do not
-need Microsoft Visual Studio to build Panda3D, though - the relevant compilers
-are included as part of the Windows 7.1 SDK.
+We currently build using the Microsoft Visual C++ 2015 compiler.  You will
+also need to install the [Windows 10 SDK](https://developer.microsoft.com/en-us/windows/downloads/windows-10-sdk),
+and if you intend to target Windows XP, you will also need the
+[Windows 7.1 SDK](https://www.microsoft.com/en-us/download/details.aspx?id=8279).
 
 You will also need to have the third-party dependency libraries available for
 the build scripts to use.  These are available from one of these two URLs,
-depending on whether you are on a 32-bit or 64-bit system:
-https://www.panda3d.org/download/panda3d-1.9.4/panda3d-1.9.4-tools-win32.zip
-https://www.panda3d.org/download/panda3d-1.9.4/panda3d-1.9.4-tools-win64.zip
+depending on whether you are on a 32-bit or 64-bit system, or you can
+[click here](https://github.com/rdb/panda3d-thirdparty) for instructions on
+building them from source.
 
-(It is also possible to build using MSVC 2015 and 2017, which requires a
-different set of thirdparty libraries, but that is not described here.)
+http://rdb.name/thirdparty-vc14-x64.7z
+http://rdb.name/thirdparty-vc14.7z
 
 After acquiring these dependencies, you may simply build Panda3D from the
-command prompt using the following command:
+command prompt using the following command.  (Add the `--windows-sdk=10`
+option if you don't need to support Windows XP.)
 
 ```bash
-makepanda\makepanda.bat --everything --installer --no-eigen
+makepanda\makepanda.bat --everything --installer --no-eigen --threads=2
 ```
 
 When the build succeeds, it will produce an .exe file that you can use to

From 9ca0d089a669f3f3e63f58f329d354055917700b Mon Sep 17 00:00:00 2001
From: Younguk Kim <bluekyu.dev@gmail.com>
Date: Tue, 10 Apr 2018 19:45:54 +0900
Subject: [PATCH 12/17] event: fix a crash when removing a task is not owned by
 user

---
 panda/src/event/asyncTaskChain.cxx | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/panda/src/event/asyncTaskChain.cxx b/panda/src/event/asyncTaskChain.cxx
index 47299d31ef..c7d732eca9 100644
--- a/panda/src/event/asyncTaskChain.cxx
+++ b/panda/src/event/asyncTaskChain.cxx
@@ -477,6 +477,7 @@ do_remove(AsyncTask *task, bool upon_death) {
     {
       int index = find_task_on_heap(_sleeping, task);
       nassertr(index != -1, false);
+      PT(AsyncTask) hold_task = task;
       _sleeping.erase(_sleeping.begin() + index);
       make_heap(_sleeping.begin(), _sleeping.end(), AsyncTaskSortWakeTime());
       cleanup_task(task, upon_death, false);
@@ -486,6 +487,7 @@ do_remove(AsyncTask *task, bool upon_death) {
   case AsyncTask::S_active:
     {
       // Active, but not being serviced, easy.
+      PT(AsyncTask) hold_task = task;
       int index = find_task_on_heap(_active, task);
       if (index != -1) {
         _active.erase(_active.begin() + index);
@@ -769,7 +771,6 @@ cleanup_task(AsyncTask *task, bool upon_death, bool clean_exit) {
   }
 
   nassertv(task->_chain == this);
-  PT(AsyncTask) hold_task = task;
 
   task->_state = AsyncTask::S_inactive;
   task->_chain = nullptr;

From 607af9ff4963db086b1233e195db45f7aeda68c1 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Tue, 10 Apr 2018 15:29:43 +0200
Subject: [PATCH 13/17] flt: fix compile error on macOS 10.6 (which has no
 strnlen)

---
 pandatool/src/flt/fltBeadID.cxx | 4 ++--
 pandatool/src/flt/fltRecord.cxx | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/pandatool/src/flt/fltBeadID.cxx b/pandatool/src/flt/fltBeadID.cxx
index f55d3e88cc..32348d583e 100644
--- a/pandatool/src/flt/fltBeadID.cxx
+++ b/pandatool/src/flt/fltBeadID.cxx
@@ -78,8 +78,8 @@ extract_record(FltRecordReader &reader) {
 bool FltBeadID::
 extract_ancillary(FltRecordReader &reader) {
   if (reader.get_opcode() == FO_long_id) {
-    vector_uchar s = reader.get_iterator().get_remaining_bytes();
-    _id.assign((const char *)s.data(), strnlen((const char *)s.data(), s.size()));
+    DatagramIterator &di = reader.get_iterator();
+    _id = di.get_fixed_string(di.get_remaining_size());
     return true;
   }
 
diff --git a/pandatool/src/flt/fltRecord.cxx b/pandatool/src/flt/fltRecord.cxx
index a0af83e180..53844f0636 100644
--- a/pandatool/src/flt/fltRecord.cxx
+++ b/pandatool/src/flt/fltRecord.cxx
@@ -621,8 +621,8 @@ extract_record(FltRecordReader &) {
 bool FltRecord::
 extract_ancillary(FltRecordReader &reader) {
   if (reader.get_opcode() == FO_comment) {
-    vector_uchar s = reader.get_iterator().get_remaining_bytes();
-    _comment.assign((const char *)s.data(), strnlen((const char *)s.data(), s.size()));
+    DatagramIterator &di = reader.get_iterator();
+    _comment = di.get_fixed_string(di.get_remaining_size());
     return true;
   }
 

From e1675f1a539c22fdb3c5ebdacaa6a5c0fb383152 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Tue, 10 Apr 2018 15:31:48 +0200
Subject: [PATCH 14/17] makepanda: fix compile error on Windows with some
 versions of flex

---
 makepanda/makepanda.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/makepanda/makepanda.py b/makepanda/makepanda.py
index b772a4a9e7..3f597f90b7 100755
--- a/makepanda/makepanda.py
+++ b/makepanda/makepanda.py
@@ -552,6 +552,7 @@ if (COMPILER == "MSVC"):
     PkgDisable("EGL")
     PkgDisable("CARBON")
     PkgDisable("COCOA")
+    DefSymbol("FLEX", "YY_NO_UNISTD_H")
     if (PkgSkip("PYTHON")==0):
         IncDirectory("ALWAYS", SDK["PYTHON"] + "/include")
         LibDirectory("ALWAYS", SDK["PYTHON"] + "/libs")
@@ -1396,7 +1397,7 @@ def CompileBison(wobj, wsrc, opts):
         CopyFile(wdsth, GetOutputDir()+"/tmp/"+ifile+".h")
 
     # Finally, compile the generated source file.
-    CompileCxx(wobj,wdstc,opts)
+    CompileCxx(wobj, wdstc, opts + ["FLEX"])
 
 ########################################################################
 ##

From 0cef19fd900977bd67eb7ed17200a62aa317f28c Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Wed, 11 Apr 2018 17:29:49 +0200
Subject: [PATCH 15/17] putil: more validation in
 DatagramInputFile::get_datagram

Intended to fix test_file_corrupt for 32-bit platforms.

See discussion in 89be2c19af74c62b57961469c779b324c69979f1
---
 panda/src/putil/datagramInputFile.cxx | 28 ++++++++++++++++++---------
 1 file changed, 19 insertions(+), 9 deletions(-)

diff --git a/panda/src/putil/datagramInputFile.cxx b/panda/src/putil/datagramInputFile.cxx
index f3bd8a081e..f81381d02e 100644
--- a/panda/src/putil/datagramInputFile.cxx
+++ b/panda/src/putil/datagramInputFile.cxx
@@ -138,35 +138,45 @@ get_datagram(Datagram &data) {
     return true;
   }
 
-  streamsize num_bytes = (streamsize)num_bytes_32;
+  size_t num_bytes = (size_t)num_bytes_32;
   if (num_bytes_32 == (uint32_t)-1) {
     // Another special case for a value larger than 32 bits.
-    num_bytes = reader.get_uint64();
-  }
+    uint64_t num_bytes_64 = reader.get_uint64();
 
-  // Make sure we have a reasonable datagram size for putting into memory.
-  nassertr(num_bytes == (size_t)num_bytes, false);
+    if (_in->fail() || _in->eof()) {
+      _error = true;
+      return false;
+    }
+
+    num_bytes = (size_t)num_bytes_64;
+
+    // Make sure we have a reasonable datagram size for putting into memory.
+    if (num_bytes_64 != (uint64_t)num_bytes) {
+      _error = true;
+      return false;
+    }
+  }
 
   // Now, read the datagram itself. We construct an empty datagram, use
   // pad_bytes to make it big enough, and read *directly* into the datagram's
   // internal buffer. Doing this saves us a copy operation.
   data = Datagram();
 
-  streamsize bytes_read = 0;
+  size_t bytes_read = 0;
   while (bytes_read < num_bytes) {
-    streamsize bytes_left = num_bytes - bytes_read;
+    size_t bytes_left = num_bytes - bytes_read;
 
     // Hold up a second - datagrams >4MB are pretty large by bam/network
     // standards. Let's take it 4MB at a time just in case the length is
     // corrupt, so we don't allocate potentially a few GBs of RAM only to
     // find a truncated file.
-    bytes_left = min(bytes_left, (streamsize)4*1024*1024);
+    bytes_left = min(bytes_left, (size_t)4*1024*1024);
 
     PTA_uchar buffer = data.modify_array();
     buffer.resize(buffer.size() + bytes_left);
     unsigned char *ptr = &buffer.p()[bytes_read];
 
-    _in->read((char *)ptr, bytes_left);
+    _in->read((char *)ptr, (streamsize)bytes_left);
     if (_in->fail() || _in->eof()) {
       _error = true;
       return false;

From f979c4d3121ded6bc0ea3f2cfea68c5d686ab137 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Wed, 11 Apr 2018 17:41:16 +0200
Subject: [PATCH 16/17] makepanda: don't use pkg-config for assimp

It seems that they removed the -I option, which we need to build with.  This commit is intended to fix the Ubuntu Bionic build.
---
 makepanda/makepanda.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/makepanda/makepanda.py b/makepanda/makepanda.py
index 3f597f90b7..5ae064b649 100755
--- a/makepanda/makepanda.py
+++ b/makepanda/makepanda.py
@@ -828,7 +828,7 @@ if (COMPILER=="GCC"):
         SmartPkgEnable("EIGEN",     "eigen3",    (), ("Eigen/Dense",), target_pkg = 'ALWAYS')
         SmartPkgEnable("ARTOOLKIT", "",          ("AR"), "AR/ar.h")
         SmartPkgEnable("FCOLLADA",  "",          ChooseLib(fcollada_libs, "FCOLLADA"), ("FCollada", "FCollada/FCollada.h"))
-        SmartPkgEnable("ASSIMP",    "assimp", ("assimp"), "assimp")
+        SmartPkgEnable("ASSIMP",    "",          ("assimp"), "assimp")
         SmartPkgEnable("FFMPEG",    ffmpeg_libs, ffmpeg_libs, ("libavformat/avformat.h", "libavcodec/avcodec.h", "libavutil/avutil.h"))
         SmartPkgEnable("SWSCALE",   "libswscale", "libswscale", ("libswscale/swscale.h"), target_pkg = "FFMPEG", thirdparty_dir = "ffmpeg")
         SmartPkgEnable("SWRESAMPLE","libswresample", "libswresample", ("libswresample/swresample.h"), target_pkg = "FFMPEG", thirdparty_dir = "ffmpeg")

From 4877e8350d58cafa42f12fe026c795656a4984a3 Mon Sep 17 00:00:00 2001
From: rdb <git@rdb.name>
Date: Wed, 18 Apr 2018 18:25:29 +0200
Subject: [PATCH 17/17] tests: fix unit test on 64-bit Ubuntu due to float
 imprecision

[skip ci]
---
 tests/bullet/test_bullet_bam.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tests/bullet/test_bullet_bam.py b/tests/bullet/test_bullet_bam.py
index c6b9d2c282..11523a4f51 100644
--- a/tests/bullet/test_bullet_bam.py
+++ b/tests/bullet/test_bullet_bam.py
@@ -88,8 +88,8 @@ def test_minkowski_sum_shape():
     assert type(shape) is type(shape2)
     assert shape.margin == shape2.margin
     assert shape.name == shape2.name
-    assert shape.transform_a.compare_to(shape2.transform_a, True) == 0
-    assert shape.transform_b.compare_to(shape2.transform_b, True) == 0
+    assert shape.transform_a.mat.compare_to(shape2.transform_a.mat) == 0
+    assert shape.transform_b.mat.compare_to(shape2.transform_b.mat) == 0
     assert type(shape.shape_a) == type(shape2.shape_a)
     assert type(shape.shape_b) == type(shape2.shape_b)