diff --git a/dtool/src/dtoolbase/dtoolbase.cxx b/dtool/src/dtoolbase/dtoolbase.cxx
index a45a1de4e0..3bd34815c9 100644
--- a/dtool/src/dtoolbase/dtoolbase.cxx
+++ b/dtool/src/dtoolbase/dtoolbase.cxx
@@ -62,4 +62,12 @@ default_thread_consider_yield() {
 void (*global_thread_yield)() = default_thread_yield;
 void (*global_thread_consider_yield)() = default_thread_consider_yield;
 
+#ifdef HAVE_PYTHON
+static PyThreadState *
+default_thread_state_swap(PyThreadState *state) {
+  return nullptr;
+}
+PyThreadState *(*global_thread_state_swap)(PyThreadState *tstate) = default_thread_state_swap;
+#endif  // HAVE_PYTHON
+
 #endif  // HAVE_THREADS && SIMPLE_THREADS
diff --git a/dtool/src/dtoolbase/dtoolbase_cc.h b/dtool/src/dtoolbase/dtoolbase_cc.h
index 36da6b2b0b..8894469422 100644
--- a/dtool/src/dtoolbase/dtoolbase_cc.h
+++ b/dtool/src/dtoolbase/dtoolbase_cc.h
@@ -233,6 +233,15 @@ INLINE void thread_consider_yield() {
   (*global_thread_consider_yield)();
 }
 
+#ifdef HAVE_PYTHON
+typedef struct _ts PyThreadState;
+extern EXPCL_DTOOL_DTOOLBASE PyThreadState *(*global_thread_state_swap)(PyThreadState *tstate);
+
+INLINE PyThreadState *thread_state_swap(PyThreadState *tstate) {
+  return (*global_thread_state_swap)(tstate);
+}
+#endif  // HAVE_PYTHON
+
 #else
 
 INLINE void thread_yield() {
diff --git a/dtool/src/dtoolutil/textEncoder.I b/dtool/src/dtoolutil/textEncoder.I
index c9eeb0ec66..aa6b42fdb5 100644
--- a/dtool/src/dtoolutil/textEncoder.I
+++ b/dtool/src/dtoolutil/textEncoder.I
@@ -316,7 +316,7 @@ unicode_ispunct(char32_t character) {
   const UnicodeLatinMap::Entry *entry = UnicodeLatinMap::look_up(character);
   if (entry == nullptr) {
     // Some punctuation marks aren't listed in the map.
-    return (character >= 0 && character < 128 && ispunct(character));
+    return (character < 128 && ispunct(character));
   }
   return entry->_char_type == UnicodeLatinMap::CT_punct;
 }
diff --git a/dtool/src/interrogatedb/py_panda.cxx b/dtool/src/interrogatedb/py_panda.cxx
index 38e774eb88..b2fa4ba3a1 100644
--- a/dtool/src/interrogatedb/py_panda.cxx
+++ b/dtool/src/interrogatedb/py_panda.cxx
@@ -754,6 +754,11 @@ PyObject *Dtool_PyModuleInitHelper(LibraryDef *defs[], const char *modulename) {
       PyErr_Clear();
     }
     initialized_main_dir = true;
+
+    // Also, while we are at it, initialize the thread swap hook.
+#if defined(HAVE_THREADS) && defined(SIMPLE_THREADS)
+    global_thread_state_swap = PyThreadState_Swap;
+#endif
   }
 
   PyModule_AddIntConstant(module, "Dtool_PyNativeInterface", 1);
diff --git a/dtool/src/parser-inc/Python.h b/dtool/src/parser-inc/Python.h
index ddd660072d..5f1a98a825 100644
--- a/dtool/src/parser-inc/Python.h
+++ b/dtool/src/parser-inc/Python.h
@@ -28,7 +28,7 @@ typedef _typeobject PyTypeObject;
 typedef struct {} PyStringObject;
 typedef struct {} PyUnicodeObject;
 
-class PyThreadState;
+typedef struct _ts PyThreadState;
 typedef int Py_ssize_t;
 typedef struct bufferinfo Py_buffer;
 
diff --git a/panda/src/glstuff/glGraphicsBuffer_src.cxx b/panda/src/glstuff/glGraphicsBuffer_src.cxx
index eab850bdba..d5a8763fc8 100644
--- a/panda/src/glstuff/glGraphicsBuffer_src.cxx
+++ b/panda/src/glstuff/glGraphicsBuffer_src.cxx
@@ -1097,6 +1097,15 @@ bind_slot_multisample(bool rb_resize, Texture **attach, RenderTexturePlane slot,
 #endif
       glgsg->_glBindRenderbuffer(GL_RENDERBUFFER_EXT, _rbm[slot]);
       GLuint format = GL_DEPTH_COMPONENT;
+#ifndef OPENGLES
+      if (_fb_properties.get_float_depth()) {
+        if (!glgsg->_use_remapped_depth_range) {
+          format = GL_DEPTH_COMPONENT32F;
+        } else {
+          format = GL_DEPTH_COMPONENT32F_NV;
+        }
+      } else
+#endif
       if (tex) {
         switch (tex->get_format()) {
           case Texture::F_depth_component16:
diff --git a/panda/src/gobj/preparedGraphicsObjects.cxx b/panda/src/gobj/preparedGraphicsObjects.cxx
index 4f6ecea1ed..96fcd80269 100644
--- a/panda/src/gobj/preparedGraphicsObjects.cxx
+++ b/panda/src/gobj/preparedGraphicsObjects.cxx
@@ -1619,8 +1619,8 @@ begin_frame(GraphicsStateGuardianBase *gsg, Thread *current_thread) {
        ++qsi) {
     Shader *shader = qsi->first;
     ShaderContext *sc = shader->prepare_now(this, gsg);
-    if (qti->second != nullptr) {
-      qti->second->set_result(sc);
+    if (qsi->second != nullptr) {
+      qsi->second->set_result(sc);
     }
   }
 
diff --git a/panda/src/gobj/textureReloadRequest.cxx b/panda/src/gobj/textureReloadRequest.cxx
index 4c17b550b7..b63acb6090 100644
--- a/panda/src/gobj/textureReloadRequest.cxx
+++ b/panda/src/gobj/textureReloadRequest.cxx
@@ -40,7 +40,7 @@ do_task() {
       // become a kind of a leak (if the texture is never rendered again on
       // this GSG, we'll just end up carrying the texture memory in RAM
       // forever, instead of dumping it as soon as it gets prepared).
-      _texture->prepare(_pgo);
+      _pgo->enqueue_texture(_texture);
     }
   }
 
diff --git a/panda/src/net/connection.cxx b/panda/src/net/connection.cxx
index aecfc111ac..27f5c8bb24 100644
--- a/panda/src/net/connection.cxx
+++ b/panda/src/net/connection.cxx
@@ -445,7 +445,7 @@ do_flush() {
     if (data_sent > 0) {
       total_sent += data_sent;
     }
-    double last_report = 0;
+
     while (!okflag && tcp->Active() &&
            (data_sent > 0 || tcp->GetLastError() == LOCAL_BLOCKING_ERROR)) {
       if (data_sent == 0) {
diff --git a/panda/src/pipeline/blockerSimple.I b/panda/src/pipeline/blockerSimple.I
index 0188281728..89be34a412 100644
--- a/panda/src/pipeline/blockerSimple.I
+++ b/panda/src/pipeline/blockerSimple.I
@@ -11,14 +11,6 @@
  * @date 2007-06-20
  */
 
-/**
- *
- */
-INLINE BlockerSimple::
-BlockerSimple() {
-  _flags = 0;
-}
-
 /**
  *
  */
diff --git a/panda/src/pipeline/blockerSimple.h b/panda/src/pipeline/blockerSimple.h
index 71ae25c41d..d375d5dc16 100644
--- a/panda/src/pipeline/blockerSimple.h
+++ b/panda/src/pipeline/blockerSimple.h
@@ -28,7 +28,7 @@
  */
 class EXPCL_PANDA_PIPELINE BlockerSimple {
 protected:
-  INLINE BlockerSimple();
+  constexpr BlockerSimple() = default;
   INLINE ~BlockerSimple();
 
 protected:
@@ -38,7 +38,7 @@ protected:
     F_has_waiters  = 0x40000000,
   };
 
-  unsigned int _flags;
+  unsigned int _flags = 0;
 
   friend class ThreadSimpleManager;
 };
diff --git a/panda/src/pipeline/contextSwitch_longjmp_src.c b/panda/src/pipeline/contextSwitch_longjmp_src.c
index c3640b8f1f..5dec92804a 100644
--- a/panda/src/pipeline/contextSwitch_longjmp_src.c
+++ b/panda/src/pipeline/contextSwitch_longjmp_src.c
@@ -1,8 +1,4 @@
-/* Filename: contextSwitch_longjmp_src.c
- * Created by:  drose (15Apr10)
- *
- * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
- *
+/**
  * PANDA 3D SOFTWARE
  * Copyright (c) Carnegie Mellon University.  All rights reserved.
  *
@@ -10,7 +6,10 @@
  * license.  You should have received a copy of this license along
  * with this source code in a file named "LICENSE."
  *
- * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+ * @file contextSwitch_longjmp_src.c
+ * @author drose
+ * @date 2010-04-15
+ */
 
 /* This is the implementation of user-space context switching using
    setmp() / longjmp().  This is the hackier implementation,
@@ -90,14 +89,14 @@ void
 cs_longjmp(cs_jmp_buf env) {
   _asm {
     mov eax, env;
-    
+
     mov ebx, [eax + 0];
     mov edi, [eax + 4];
     mov esi, [eax + 8];
     mov ebp, [eax + 12];
     mov esp, [eax + 16];
     mov edx, [eax + 20];
-    
+
     frstor [eax + 24];  /* restore floating-point state */
 
     mov eax, 1;   /* return 1 from setjmp: pass 2 return */
@@ -251,7 +250,7 @@ setup_context_1(void) {
 }
 
 void
-init_thread_context(struct ThreadContext *context, 
+init_thread_context(struct ThreadContext *context,
                     unsigned char *stack, size_t stack_size,
                     ThreadFunction *thread_func, void *data) {
   /* Copy all of the input parameters to static variables, then begin
@@ -263,7 +262,7 @@ init_thread_context(struct ThreadContext *context,
   st_data = data;
 
   setup_context_1();
-}  
+}
 
 void
 save_thread_context(struct ThreadContext *context,
diff --git a/panda/src/pipeline/contextSwitch_posix_src.c b/panda/src/pipeline/contextSwitch_posix_src.c
index 6f5df46445..f553cefc45 100644
--- a/panda/src/pipeline/contextSwitch_posix_src.c
+++ b/panda/src/pipeline/contextSwitch_posix_src.c
@@ -1,8 +1,4 @@
-/* Filename: contextSwitch_posix_src.c
- * Created by:  drose (15Apr10)
- *
- * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
- *
+/**
  * PANDA 3D SOFTWARE
  * Copyright (c) Carnegie Mellon University.  All rights reserved.
  *
@@ -10,7 +6,10 @@
  * license.  You should have received a copy of this license along
  * with this source code in a file named "LICENSE."
  *
- * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+ * @file contextSwitch_posix_src.c
+ * @author drose
+ * @date 2010-04-15
+ */
 
 /* This is the implementation of user-space context switching using
    posix threads to manage the different execution contexts.  This
@@ -44,7 +43,7 @@ struct ThreadContext {
   pthread_mutex_t _ready_mutex;
   pthread_cond_t _ready_cvar;
   int _ready_flag;
-  
+
   /* This is set FALSE while the thread is alive, and TRUE if the
      thread is to be terminated when it next wakes up. */
   int _terminated;
@@ -83,19 +82,19 @@ thread_main(void *data) {
 }
 
 void
-init_thread_context(struct ThreadContext *context, 
+init_thread_context(struct ThreadContext *context,
                     unsigned char *stack, size_t stack_size,
                     ThreadFunction *thread_func, void *data) {
   context->_thread_func = thread_func;
   context->_data = data;
 
-  pthread_attr_t attr; 
-  pthread_attr_init(&attr); 
+  pthread_attr_t attr;
+  pthread_attr_init(&attr);
   pthread_attr_setstacksize(&attr, stack_size);
-  pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEM); 
+  pthread_attr_setscope(&attr, PTHREAD_SCOPE_SYSTEM);
 
-  pthread_create(&(context->_thread), &attr, thread_main, context); 
-  pthread_attr_destroy(&attr); 
+  pthread_create(&(context->_thread), &attr, thread_main, context);
+  pthread_attr_destroy(&attr);
 }
 
 void
@@ -142,7 +141,7 @@ switch_to_thread_context(struct ThreadContext *from_context,
     /* We've been rudely terminated.  Exit gracefully. */
     pthread_exit(NULL);
   }
-  
+
   /* Now we have been signaled again, and we're ready to resume the
      thread. */
   longjmp(from_context->_jmp_context, 1);
@@ -164,7 +163,7 @@ alloc_thread_context() {
   pthread_mutexattr_init(&attr);
   // The symbol PTHREAD_MUTEX_DEFAULT isn't always available?
   //  pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_DEFAULT);
-  int result = pthread_mutex_init(&context->_ready_mutex, &attr);
+  pthread_mutex_init(&context->_ready_mutex, &attr);
   pthread_mutexattr_destroy(&attr);
 
   pthread_cond_init(&context->_ready_cvar, NULL);
diff --git a/panda/src/pipeline/contextSwitch_ucontext_src.c b/panda/src/pipeline/contextSwitch_ucontext_src.c
index f589dbb5bf..f08c6d9afe 100644
--- a/panda/src/pipeline/contextSwitch_ucontext_src.c
+++ b/panda/src/pipeline/contextSwitch_ucontext_src.c
@@ -1,8 +1,4 @@
-/* Filename: contextSwitch_ucontext_src.c
- * Created by:  drose (15Apr10)
- *
- * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
- *
+/**
  * PANDA 3D SOFTWARE
  * Copyright (c) Carnegie Mellon University.  All rights reserved.
  *
@@ -10,7 +6,10 @@
  * license.  You should have received a copy of this license along
  * with this source code in a file named "LICENSE."
  *
- * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+ * @file contextSwitch_ucontext_src.c
+ * @author drose
+ * @date 2010-04-15
+ */
 
 /* This is the implementation of user-space context switching using
    getcontext() / setcontext().  This is the preferred implementation,
@@ -43,7 +42,7 @@ begin_context(ThreadFunction *thread_func, void *data) {
 }
 
 void
-init_thread_context(struct ThreadContext *context, 
+init_thread_context(struct ThreadContext *context,
                     unsigned char *stack, size_t stack_size,
                     ThreadFunction *thread_func, void *data) {
   if (getcontext(&context->_ucontext) != 0) {
diff --git a/panda/src/pipeline/contextSwitch_windows_src.c b/panda/src/pipeline/contextSwitch_windows_src.c
index 9f157d8eec..727eef43b9 100644
--- a/panda/src/pipeline/contextSwitch_windows_src.c
+++ b/panda/src/pipeline/contextSwitch_windows_src.c
@@ -1,8 +1,4 @@
-/* Filename: contextSwitch_windows_src.c
- * Created by:  drose (15Apr10)
- *
- * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
- *
+/**
  * PANDA 3D SOFTWARE
  * Copyright (c) Carnegie Mellon University.  All rights reserved.
  *
@@ -10,7 +6,10 @@
  * license.  You should have received a copy of this license along
  * with this source code in a file named "LICENSE."
  *
- * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+ * @file contextSwitch_windows_src.c
+ * @author drose
+ * @date 2010-04-15
+ */
 
 /* This is the implementation of user-space context switching using
    native Windows threading constructs to manage the different
@@ -37,7 +36,7 @@ struct ThreadContext {
   /* This event is in the signaled state when the thread is ready to
      roll. */
   HANDLE _ready;
-  
+
   /* This is set FALSE while the thread is alive, and TRUE if the
      thread is to be terminated when it next wakes up. */
   int _terminated;
@@ -71,13 +70,13 @@ thread_main(LPVOID data) {
 }
 
 void
-init_thread_context(struct ThreadContext *context, 
+init_thread_context(struct ThreadContext *context,
                     unsigned char *stack, size_t stack_size,
                     ThreadFunction *thread_func, void *data) {
   context->_thread_func = thread_func;
   context->_data = data;
 
-  context->_thread = CreateThread(NULL, stack_size, 
+  context->_thread = CreateThread(NULL, stack_size,
                                   thread_main, context, 0, NULL);
 }
 
@@ -117,7 +116,7 @@ switch_to_thread_context(struct ThreadContext *from_context,
     /* We've been rudely terminated.  Exit gracefully. */
     ExitThread(1);
   }
-  
+
   /* Now we have been signaled again, and we're ready to resume the
      thread. */
   longjmp(from_context->_jmp_context, 1);
diff --git a/panda/src/pipeline/pythonThread.cxx b/panda/src/pipeline/pythonThread.cxx
index ab41070fb8..53a811401e 100644
--- a/panda/src/pipeline/pythonThread.cxx
+++ b/panda/src/pipeline/pythonThread.cxx
@@ -225,7 +225,7 @@ call_python_func(PyObject *function, PyObject *args) {
 
     } else {
       // No exception.  Restore the thread state normally.
-      PyThreadState *state = PyThreadState_Swap(orig_thread_state);
+      PyThreadState_Swap(orig_thread_state);
       thread_states.push_back(new_thread_state);
       // PyThreadState_Clear(new_thread_state);
       // PyThreadState_Delete(new_thread_state);
diff --git a/panda/src/pipeline/threadSimpleImpl.I b/panda/src/pipeline/threadSimpleImpl.I
index 001f3037d4..d712892883 100644
--- a/panda/src/pipeline/threadSimpleImpl.I
+++ b/panda/src/pipeline/threadSimpleImpl.I
@@ -51,14 +51,6 @@ is_threading_supported() {
   return true;
 }
 
-/**
- *
- */
-INLINE bool ThreadSimpleImpl::
-is_true_threads() {
-  return (is_os_threads != 0);
-}
-
 /**
  *
  */
diff --git a/panda/src/pipeline/threadSimpleImpl.cxx b/panda/src/pipeline/threadSimpleImpl.cxx
index a631421503..14d6f7561f 100644
--- a/panda/src/pipeline/threadSimpleImpl.cxx
+++ b/panda/src/pipeline/threadSimpleImpl.cxx
@@ -141,8 +141,8 @@ start(ThreadPriority priority, bool joinable) {
 
 #ifdef HAVE_PYTHON
   // Query the current Python thread state.
-  _python_state = PyThreadState_Swap(nullptr);
-  PyThreadState_Swap(_python_state);
+  _python_state = thread_state_swap(nullptr);
+  thread_state_swap(_python_state);
 #endif  // HAVE_PYTHON
 
   init_thread_context(_context, _stack, _stack_size, st_begin_thread, this);
@@ -201,6 +201,14 @@ prepare_for_exit() {
   manager->prepare_for_exit();
 }
 
+/**
+ *
+ */
+bool ThreadSimpleImpl::
+is_true_threads() {
+  return (is_os_threads != 0);
+}
+
 /**
  *
  */
@@ -238,7 +246,7 @@ st_begin_thread(void *data) {
 void ThreadSimpleImpl::
 begin_thread() {
 #ifdef HAVE_PYTHON
-  PyThreadState_Swap(_python_state);
+  thread_state_swap(_python_state);
 #endif  // HAVE_PYTHON
 
 #ifdef HAVE_POSIX_THREADS
diff --git a/panda/src/pipeline/threadSimpleImpl.h b/panda/src/pipeline/threadSimpleImpl.h
index c552dd1357..5bd6af3fdc 100644
--- a/panda/src/pipeline/threadSimpleImpl.h
+++ b/panda/src/pipeline/threadSimpleImpl.h
@@ -63,7 +63,7 @@ public:
 
   INLINE static void bind_thread(Thread *thread);
   INLINE static bool is_threading_supported();
-  INLINE static bool is_true_threads();
+  static bool is_true_threads();
   INLINE static bool is_simple_threads();
   INLINE static void sleep(double seconds);
   INLINE static void yield();
diff --git a/panda/src/pipeline/threadSimpleManager.cxx b/panda/src/pipeline/threadSimpleManager.cxx
index 4d9890dfd4..861e19cd77 100644
--- a/panda/src/pipeline/threadSimpleManager.cxx
+++ b/panda/src/pipeline/threadSimpleManager.cxx
@@ -20,7 +20,9 @@
 #include "mainThread.h"
 
 #ifdef WIN32
-#define WIN32_LEAN_AND_MEAN
+#ifndef WIN32_LEAN_AND_MEAN
+#define WIN32_LEAN_AND_MEAN 1
+#endif
 #include <windows.h>
 #endif
 
@@ -235,7 +237,7 @@ next_context() {
 
 #ifdef HAVE_PYTHON
   // Save the current Python thread state.
-  _current_thread->_python_state = PyThreadState_Swap(nullptr);
+  _current_thread->_python_state = thread_state_swap(nullptr);
 #endif  // HAVE_PYTHON
 
 #ifdef DO_PSTATS
@@ -256,7 +258,7 @@ next_context() {
 #endif  // DO_PSTATS
 
 #ifdef HAVE_PYTHON
-  PyThreadState_Swap(_current_thread->_python_state);
+  thread_state_swap(_current_thread->_python_state);
 #endif  // HAVE_PYTHON
 }
 
@@ -468,16 +470,6 @@ init_pointers() {
     _pointers_initialized = true;
     _global_ptr = new ThreadSimpleManager;
     Thread::get_main_thread();
-
-#ifdef HAVE_PYTHON
-    // Ensure that the Python threading system is initialized and ready to go.
-
-#if PY_VERSION_HEX >= 0x03020000
-    Py_Initialize();
-#endif
-
-    PyEval_InitThreads();
-#endif
   }
 }
 
diff --git a/panda/src/windisplay/winGraphicsWindow.cxx b/panda/src/windisplay/winGraphicsWindow.cxx
index b42ee43992..703aba0149 100644
--- a/panda/src/windisplay/winGraphicsWindow.cxx
+++ b/panda/src/windisplay/winGraphicsWindow.cxx
@@ -293,13 +293,29 @@ set_properties_now(WindowProperties &properties) {
       _properties.set_fixed_size(properties.get_fixed_size());
       properties.clear_fixed_size();
     }
+    // When switching undecorated mode, Windows will keep the window at the
+    // current outer size, whereas we want to keep it with the configured
+    // inner size.  Store the current size and origin.
+    LPoint2i top_left = _properties.get_origin();
+    LPoint2i bottom_right = top_left + _properties.get_size();
+
     DWORD window_style = make_style(_properties);
     SetWindowLong(_hWnd, GWL_STYLE, window_style);
 
+    // Now calculate the proper size and origin with the new window style.
+    RECT view_rect;
+    SetRect(&view_rect, top_left[0], top_left[1],
+            bottom_right[0], bottom_right[1]);
+    WINDOWINFO wi;
+    GetWindowInfo(_hWnd, &wi);
+    AdjustWindowRectEx(&view_rect, wi.dwStyle, FALSE, wi.dwExStyle);
+
     // We need to call this to ensure that the style change takes effect.
-    SetWindowPos(_hWnd, HWND_NOTOPMOST, 0, 0, 0, 0,
-      SWP_NOMOVE | SWP_NOSIZE | SWP_NOZORDER | SWP_NOACTIVATE |
-      SWP_FRAMECHANGED | SWP_NOSENDCHANGING | SWP_SHOWWINDOW);
+    SetWindowPos(_hWnd, HWND_NOTOPMOST, view_rect.left, view_rect.top,
+                 view_rect.right - view_rect.left,
+                 view_rect.bottom - view_rect.top,
+                 SWP_NOZORDER | SWP_NOACTIVATE | SWP_FRAMECHANGED |
+                 SWP_NOSENDCHANGING | SWP_SHOWWINDOW);
   }
 
   if (properties.has_title()) {