add ParasiteBuffer

panda/src/display/Sources.pp

@@ -34,6 +34,7 @@
     graphicsWindowInputDevice.I  \
     graphicsWindowInputDevice.h \
     graphicsDevice.h graphicsDevice.I \
+    parasiteBuffer.I parasiteBuffer.h \
     windowProperties.I windowProperties.h \
     hardwareChannel.I  \
     hardwareChannel.h \
@@ -56,6 +57,7 @@
     graphicsThreadingModel.cxx \
     graphicsWindow.cxx graphicsWindowInputDevice.cxx  \
     graphicsDevice.cxx \
+    parasiteBuffer.cxx \
     windowProperties.cxx \
     hardwareChannel.cxx \
     savedFrameBuffer.cxx
@@ -81,6 +83,7 @@
     graphicsThreadingModel.I graphicsThreadingModel.h \
     graphicsWindowInputDevice.I graphicsWindowInputDevice.h \
     graphicsDevice.I graphicsDevice.h \
+    parasiteBuffer.I parasiteBuffer.h \
     windowProperties.I windowProperties.h \
     hardwareChannel.I hardwareChannel.h \
     lensStack.I lensStack.h \

panda/src/display/config_display.cxx

@@ -26,6 +26,7 @@
 #include "graphicsWindow.h"
 #include "graphicsChannel.h"
 #include "graphicsLayer.h"
+#include "parasiteBuffer.h"
 #include "hardwareChannel.h"
 #include "textureContext.h"
 #include "geomNodeContext.h"
@@ -116,6 +117,7 @@ init_libdisplay() {
   GraphicsChannel::init_type();
   GraphicsLayer::init_type();
   HardwareChannel::init_type();
+  ParasiteBuffer::init_type();
   TextureContext::init_type();
   GeomNodeContext::init_type();
   GeomContext::init_type();

panda/src/display/display_composite2.cxx

@@ -9,3 +9,4 @@
 #include "graphicsWindow.cxx"
 #include "graphicsBuffer.cxx"
 #include "graphicsOutput.cxx"
+#include "parasiteBuffer.cxx"

panda/src/display/graphicsBuffer.cxx

@@ -38,7 +38,8 @@ GraphicsBuffer(GraphicsPipe *pipe, GraphicsStateGuardian *gsg,
 
   if (display_cat.is_debug()) {
     display_cat.debug()
-      << "Creating new offscreen buffer using GSG " << (void *)gsg << "\n";
+      << "Creating new offscreen buffer " << get_name()
+      << " using GSG " << (void *)gsg << "\n";
   }
 
   if (want_texture) {

panda/src/display/graphicsEngine.cxx

@@ -18,6 +18,7 @@
 
 #include "graphicsEngine.h"
 #include "graphicsPipe.h"
+#include "parasiteBuffer.h"
 #include "config_display.h"
 #include "pipeline.h"
 #include "drawCullHandler.h"
@@ -274,6 +275,54 @@ make_buffer(GraphicsStateGuardian *gsg, const string &name,
   return buffer;
 }
 
+////////////////////////////////////////////////////////////////////
+//     Function: GraphicsEngine::make_parasite
+//       Access: Published
+//  Description: Creates a new offscreen parasite buffer based on the
+//               indicated host.  See parasiteBuffer.h.  The
+//               GraphicsEngine becomes the owner of the buffer; it
+//               will persist at least until remove_window() is called
+//               later.
+//
+//               This usually returns a ParasiteBuffer object, but it
+//               may actually return a GraphicsWindow if show-buffers
+//               is configured true.
+////////////////////////////////////////////////////////////////////
+GraphicsOutput *GraphicsEngine::
+make_parasite(GraphicsOutput *host, const string &name, 
+              int sort, int x_size, int y_size) {
+  GraphicsStateGuardian *gsg = host->get_gsg();
+
+  if (show_buffers) {
+    GraphicsWindow *window = make_window(gsg, name, sort);
+    if (window != (GraphicsWindow *)NULL) {
+      WindowProperties props;
+      props.set_size(x_size, y_size);
+      props.set_fixed_size(true);
+      props.set_title(name);
+      window->request_properties(props);
+
+      window->_texture = new Texture();
+      window->_texture->set_name(name);
+      window->_copy_texture = true;
+
+      return window;
+    }
+  }
+
+  GraphicsThreadingModel threading_model = get_threading_model();
+  nassertr(gsg != (GraphicsStateGuardian *)NULL, NULL);
+  nassertr(this == gsg->get_engine(), NULL);
+  nassertr(threading_model.get_draw_name() ==
+           gsg->get_threading_model().get_draw_name(), NULL);
+
+  ParasiteBuffer *buffer = new ParasiteBuffer(host, name, x_size, y_size);
+  buffer->_sort = sort;
+  do_add_window(buffer, gsg, threading_model);
+
+  return buffer;
+}
+
 ////////////////////////////////////////////////////////////////////
 //     Function: GraphicsEngine::remove_window
 //       Access: Published

panda/src/display/graphicsEngine.h

@@ -79,6 +79,8 @@ PUBLISHED:
   GraphicsOutput *make_buffer(GraphicsStateGuardian *gsg, const string &name,
                               int sort,
                               int x_size, int y_size, bool want_texture);
+  GraphicsOutput *make_parasite(GraphicsOutput *host, const string &name,
+                                int sort, int x_size, int y_size);
 
   bool remove_window(GraphicsOutput *window);
   void remove_all_windows();

panda/src/display/graphicsWindow.cxx

@@ -45,7 +45,8 @@ GraphicsWindow(GraphicsPipe *pipe, GraphicsStateGuardian *gsg,
 
   if (display_cat.is_debug()) {
     display_cat.debug()
-      << "Creating new window using GSG " << (void *)gsg << "\n";
+      << "Creating new window " << get_name()
+      << " using GSG " << (void *)gsg << "\n";
   }
 
   // Some default properties for windows unless specified otherwise.

panda/src/display/parasiteBuffer.I

@@ -0,0 +1,18 @@
+// Filename: parasiteBuffer.I
+// Created by:  drose (27Feb04)
+//
+////////////////////////////////////////////////////////////////////
+//
+// PANDA 3D SOFTWARE
+// Copyright (c) 2001 - 2004, Disney Enterprises, Inc.  All rights reserved
+//
+// All use of this software is subject to the terms of the Panda 3d
+// Software license.  You should have received a copy of this license
+// along with this source code; you will also find a current copy of
+// the license at http://etc.cmu.edu/panda3d/docs/license/ .
+//
+// To contact the maintainers of this program write to
+// panda3d-general@lists.sourceforge.net .
+//
+////////////////////////////////////////////////////////////////////
+

panda/src/display/parasiteBuffer.cxx

@@ -0,0 +1,90 @@
+// Filename: parasiteBuffer.cxx
+// Created by:  drose (27Feb04)
+//
+////////////////////////////////////////////////////////////////////
+//
+// PANDA 3D SOFTWARE
+// Copyright (c) 2001 - 2004, Disney Enterprises, Inc.  All rights reserved
+//
+// All use of this software is subject to the terms of the Panda 3d
+// Software license.  You should have received a copy of this license
+// along with this source code; you will also find a current copy of
+// the license at http://etc.cmu.edu/panda3d/docs/license/ .
+//
+// To contact the maintainers of this program write to
+// panda3d-general@lists.sourceforge.net .
+//
+////////////////////////////////////////////////////////////////////
+
+
+#include "parasiteBuffer.h"
+
+TypeHandle ParasiteBuffer::_type_handle;
+
+////////////////////////////////////////////////////////////////////
+//     Function: ParasiteBuffer::Constructor
+//       Access: Public
+//  Description: Normally, the ParasiteBuffer constructor is not
+//               called directly; these are created instead via the
+//               GraphicsEngine::make_parasite() function.
+////////////////////////////////////////////////////////////////////
+ParasiteBuffer::
+ParasiteBuffer(GraphicsOutput *host, const string &name,
+               int x_size, int y_size) :
+  GraphicsOutput(host->get_pipe(), host->get_gsg(), name),
+  _host(host)
+{
+#ifdef DO_MEMORY_USAGE
+  MemoryUsage::update_type(this, this);
+#endif
+  
+  if (display_cat.is_debug()) {
+    display_cat.debug()
+      << "Creating new parasite buffer " << get_name()
+      << " on " << _host->get_name() << "\n";
+  }
+
+  _texture = new Texture();
+  _texture->set_name(_name);
+  _copy_texture = true;
+
+  _x_size = x_size;
+  _y_size = y_size;
+  _has_size = true;
+
+  _is_valid = true;
+
+  nassertv(_x_size < host->get_x_size() && _y_size < host->get_y_size());
+}
+
+////////////////////////////////////////////////////////////////////
+//     Function: ParasiteBuffer::Destructor
+//       Access: Published, Virtual
+//  Description: 
+////////////////////////////////////////////////////////////////////
+ParasiteBuffer::
+~ParasiteBuffer() {
+}
+
+////////////////////////////////////////////////////////////////////
+//     Function: ParasiteBuffer::is_active
+//       Access: Published, Virtual
+//  Description: Returns true if the window is ready to be rendered
+//               into, false otherwise.
+////////////////////////////////////////////////////////////////////
+bool ParasiteBuffer::
+is_active() const {
+  return _host->is_active();
+}
+
+////////////////////////////////////////////////////////////////////
+//     Function: ParasiteBuffer::make_current
+//       Access: Public, Virtual
+//  Description: This function will be called within the draw thread
+//               during begin_frame() to ensure the graphics context
+//               is ready for drawing.
+////////////////////////////////////////////////////////////////////
+void ParasiteBuffer::
+make_current() {
+  _host->make_current();
+}

panda/src/display/parasiteBuffer.h

@@ -0,0 +1,91 @@
+// Filename: parasiteBuffer.h
+// Created by:  drose (27Feb04)
+//
+////////////////////////////////////////////////////////////////////
+//
+// PANDA 3D SOFTWARE
+// Copyright (c) 2001 - 2004, Disney Enterprises, Inc.  All rights reserved
+//
+// All use of this software is subject to the terms of the Panda 3d
+// Software license.  You should have received a copy of this license
+// along with this source code; you will also find a current copy of
+// the license at http://etc.cmu.edu/panda3d/docs/license/ .
+//
+// To contact the maintainers of this program write to
+// panda3d-general@lists.sourceforge.net .
+//
+////////////////////////////////////////////////////////////////////
+
+#ifndef PARASITEBUFFER_H
+#define PARASITEBUFFER_H
+
+#include "pandabase.h"
+
+#include "graphicsOutput.h"
+#include "texture.h"
+#include "pointerTo.h"
+
+////////////////////////////////////////////////////////////////////
+//       Class : ParasiteBuffer
+// Description : This is a special GraphicsOutput type that acts a lot
+//               like a GraphicsBuffer, effectively allowing rendering
+//               to an offscreen buffer, except it does not create any
+//               framebuffer space for itself.  Instead, it renders
+//               into the framebuffer owned by some other
+//               GraphicsOutput.
+//
+//               The x_size and y_size must therefore fit within the
+//               bounds of the source GraphicsOutput.
+//
+//               Since the framebuffer will be subsequently cleared
+//               when the actual owner draws in it later, this only
+//               makes sense if we are going to copy the contents of
+//               the framebuffer to a texture immediately after we
+//               draw it.  Thus, has_texture() is implicitly true for
+//               a ParasiteBuffer.
+//
+//               This class is useful to render offscreen to a texture
+//               while preventing the waste of framebuffer memory for
+//               API's that are unable to render directly into a
+//               texture (and must render into a separate framebuffer
+//               first and then copy to texture).  It is also the only
+//               way to render to a texture on API's that do not
+//               support offscreen rendering.
+////////////////////////////////////////////////////////////////////
+class EXPCL_PANDA ParasiteBuffer : public GraphicsOutput {
+public:
+  ParasiteBuffer(GraphicsOutput *host, const string &name,
+                 int x_size, int y_size);
+
+PUBLISHED:
+  virtual ~ParasiteBuffer();
+
+  virtual bool is_active() const;
+
+public:
+  virtual void make_current();
+
+private:
+  PT(GraphicsOutput) _host;
+  
+public:
+  static TypeHandle get_class_type() {
+    return _type_handle;
+  }
+  static void init_type() {
+    GraphicsOutput::init_type();
+    register_type(_type_handle, "ParasiteBuffer",
+                  GraphicsOutput::get_class_type());
+  }
+  virtual TypeHandle get_type() const {
+    return get_class_type();
+  }
+  virtual TypeHandle force_init_type() {init_type(); return get_class_type();}
+
+private:
+  static TypeHandle _type_handle;
+};
+
+#include "parasiteBuffer.I"
+
+#endif