Update tri and cube with stage

These changes were cherry-picked from nvidia-dev-20150218 and
KhronosGroup/GDC-stable.
diff --git a/demos/zlib/contrib/iostream/test.cpp b/demos/zlib/contrib/iostream/test.cpp
new file mode 100644
index 0000000..7d265b3
--- /dev/null
+++ b/demos/zlib/contrib/iostream/test.cpp
@@ -0,0 +1,24 @@
+
+#include "zfstream.h"
+
+int main() {
+
+  // Construct a stream object with this filebuffer.  Anything sent
+  // to this stream will go to standard out.
+  gzofstream os( 1, ios::out );
+
+  // This text is getting compressed and sent to stdout.
+  // To prove this, run 'test | zcat'.
+  os << "Hello, Mommy" << endl;
+
+  os << setcompressionlevel( Z_NO_COMPRESSION );
+  os << "hello, hello, hi, ho!" << endl;
+
+  setcompressionlevel( os, Z_DEFAULT_COMPRESSION )
+    << "I'm compressing again" << endl;
+
+  os.close();
+
+  return 0;
+
+}
diff --git a/demos/zlib/contrib/iostream/zfstream.cpp b/demos/zlib/contrib/iostream/zfstream.cpp
new file mode 100644
index 0000000..d0cd85f
--- /dev/null
+++ b/demos/zlib/contrib/iostream/zfstream.cpp
@@ -0,0 +1,329 @@
+
+#include "zfstream.h"
+
+gzfilebuf::gzfilebuf() :
+  file(NULL),
+  mode(0),
+  own_file_descriptor(0)
+{ }
+
+gzfilebuf::~gzfilebuf() {
+
+  sync();
+  if ( own_file_descriptor )
+    close();
+
+}
+
+gzfilebuf *gzfilebuf::open( const char *name,
+                            int io_mode ) {
+
+  if ( is_open() )
+    return NULL;
+
+  char char_mode[10];
+  char *p = char_mode;
+
+  if ( io_mode & ios::in ) {
+    mode = ios::in;
+    *p++ = 'r';
+  } else if ( io_mode & ios::app ) {
+    mode = ios::app;
+    *p++ = 'a';
+  } else {
+    mode = ios::out;
+    *p++ = 'w';
+  }
+
+  if ( io_mode & ios::binary ) {
+    mode |= ios::binary;
+    *p++ = 'b';
+  }
+
+  // Hard code the compression level
+  if ( io_mode & (ios::out|ios::app )) {
+    *p++ = '9';
+  }
+
+  // Put the end-of-string indicator
+  *p = '\0';
+
+  if ( (file = gzopen(name, char_mode)) == NULL )
+    return NULL;
+
+  own_file_descriptor = 1;
+
+  return this;
+
+}
+
+gzfilebuf *gzfilebuf::attach( int file_descriptor,
+                              int io_mode ) {
+
+  if ( is_open() )
+    return NULL;
+
+  char char_mode[10];
+  char *p = char_mode;
+
+  if ( io_mode & ios::in ) {
+    mode = ios::in;
+    *p++ = 'r';
+  } else if ( io_mode & ios::app ) {
+    mode = ios::app;
+    *p++ = 'a';
+  } else {
+    mode = ios::out;
+    *p++ = 'w';
+  }
+
+  if ( io_mode & ios::binary ) {
+    mode |= ios::binary;
+    *p++ = 'b';
+  }
+
+  // Hard code the compression level
+  if ( io_mode & (ios::out|ios::app )) {
+    *p++ = '9';
+  }
+
+  // Put the end-of-string indicator
+  *p = '\0';
+
+  if ( (file = gzdopen(file_descriptor, char_mode)) == NULL )
+    return NULL;
+
+  own_file_descriptor = 0;
+
+  return this;
+
+}
+
+gzfilebuf *gzfilebuf::close() {
+
+  if ( is_open() ) {
+
+    sync();
+    gzclose( file );
+    file = NULL;
+
+  }
+
+  return this;
+
+}
+
+int gzfilebuf::setcompressionlevel( int comp_level ) {
+
+  return gzsetparams(file, comp_level, -2);
+
+}
+
+int gzfilebuf::setcompressionstrategy( int comp_strategy ) {
+
+  return gzsetparams(file, -2, comp_strategy);
+
+}
+
+
+streampos gzfilebuf::seekoff( streamoff off, ios::seek_dir dir, int which ) {
+
+  return streampos(EOF);
+
+}
+
+int gzfilebuf::underflow() {
+
+  // If the file hasn't been opened for reading, error.
+  if ( !is_open() || !(mode & ios::in) )
+    return EOF;
+
+  // if a buffer doesn't exists, allocate one.
+  if ( !base() ) {
+
+    if ( (allocate()) == EOF )
+      return EOF;
+    setp(0,0);
+
+  } else {
+
+    if ( in_avail() )
+      return (unsigned char) *gptr();
+
+    if ( out_waiting() ) {
+      if ( flushbuf() == EOF )
+        return EOF;
+    }
+
+  }
+
+  // Attempt to fill the buffer.
+
+  int result = fillbuf();
+  if ( result == EOF ) {
+    // disable get area
+    setg(0,0,0);
+    return EOF;
+  }
+
+  return (unsigned char) *gptr();
+
+}
+
+int gzfilebuf::overflow( int c ) {
+
+  if ( !is_open() || !(mode & ios::out) )
+    return EOF;
+
+  if ( !base() ) {
+    if ( allocate() == EOF )
+      return EOF;
+    setg(0,0,0);
+  } else {
+    if (in_avail()) {
+        return EOF;
+    }
+    if (out_waiting()) {
+      if (flushbuf() == EOF)
+        return EOF;
+    }
+  }
+
+  int bl = blen();
+  setp( base(), base() + bl);
+
+  if ( c != EOF ) {
+
+    *pptr() = c;
+    pbump(1);
+
+  }
+
+  return 0;
+
+}
+
+int gzfilebuf::sync() {
+
+  if ( !is_open() )
+    return EOF;
+
+  if ( out_waiting() )
+    return flushbuf();
+
+  return 0;
+
+}
+
+int gzfilebuf::flushbuf() {
+
+  int n;
+  char *q;
+
+  q = pbase();
+  n = pptr() - q;
+
+  if ( gzwrite( file, q, n) < n )
+    return EOF;
+
+  setp(0,0);
+
+  return 0;
+
+}
+
+int gzfilebuf::fillbuf() {
+
+  int required;
+  char *p;
+
+  p = base();
+
+  required = blen();
+
+  int t = gzread( file, p, required );
+
+  if ( t <= 0) return EOF;
+
+  setg( base(), base(), base()+t);
+
+  return t;
+
+}
+
+gzfilestream_common::gzfilestream_common() :
+  ios( gzfilestream_common::rdbuf() )
+{ }
+
+gzfilestream_common::~gzfilestream_common()
+{ }
+
+void gzfilestream_common::attach( int fd, int io_mode ) {
+
+  if ( !buffer.attach( fd, io_mode) )
+    clear( ios::failbit | ios::badbit );
+  else
+    clear();
+
+}
+
+void gzfilestream_common::open( const char *name, int io_mode ) {
+
+  if ( !buffer.open( name, io_mode ) )
+    clear( ios::failbit | ios::badbit );
+  else
+    clear();
+
+}
+
+void gzfilestream_common::close() {
+
+  if ( !buffer.close() )
+    clear( ios::failbit | ios::badbit );
+
+}
+
+gzfilebuf *gzfilestream_common::rdbuf()
+{
+  return &buffer;
+}
+
+gzifstream::gzifstream() :
+  ios( gzfilestream_common::rdbuf() )
+{
+  clear( ios::badbit );
+}
+
+gzifstream::gzifstream( const char *name, int io_mode ) :
+  ios( gzfilestream_common::rdbuf() )
+{
+  gzfilestream_common::open( name, io_mode );
+}
+
+gzifstream::gzifstream( int fd, int io_mode ) :
+  ios( gzfilestream_common::rdbuf() )
+{
+  gzfilestream_common::attach( fd, io_mode );
+}
+
+gzifstream::~gzifstream() { }
+
+gzofstream::gzofstream() :
+  ios( gzfilestream_common::rdbuf() )
+{
+  clear( ios::badbit );
+}
+
+gzofstream::gzofstream( const char *name, int io_mode ) :
+  ios( gzfilestream_common::rdbuf() )
+{
+  gzfilestream_common::open( name, io_mode );
+}
+
+gzofstream::gzofstream( int fd, int io_mode ) :
+  ios( gzfilestream_common::rdbuf() )
+{
+  gzfilestream_common::attach( fd, io_mode );
+}
+
+gzofstream::~gzofstream() { }
diff --git a/demos/zlib/contrib/iostream/zfstream.h b/demos/zlib/contrib/iostream/zfstream.h
new file mode 100644
index 0000000..ed79098
--- /dev/null
+++ b/demos/zlib/contrib/iostream/zfstream.h
@@ -0,0 +1,128 @@
+
+#ifndef zfstream_h
+#define zfstream_h
+
+#include <fstream.h>
+#include "zlib.h"
+
+class gzfilebuf : public streambuf {
+
+public:
+
+  gzfilebuf( );
+  virtual ~gzfilebuf();
+
+  gzfilebuf *open( const char *name, int io_mode );
+  gzfilebuf *attach( int file_descriptor, int io_mode );
+  gzfilebuf *close();
+
+  int setcompressionlevel( int comp_level );
+  int setcompressionstrategy( int comp_strategy );
+
+  inline int is_open() const { return (file !=NULL); }
+
+  virtual streampos seekoff( streamoff, ios::seek_dir, int );
+
+  virtual int sync();
+
+protected:
+
+  virtual int underflow();
+  virtual int overflow( int = EOF );
+
+private:
+
+  gzFile file;
+  short mode;
+  short own_file_descriptor;
+
+  int flushbuf();
+  int fillbuf();
+
+};
+
+class gzfilestream_common : virtual public ios {
+
+  friend class gzifstream;
+  friend class gzofstream;
+  friend gzofstream &setcompressionlevel( gzofstream &, int );
+  friend gzofstream &setcompressionstrategy( gzofstream &, int );
+
+public:
+  virtual ~gzfilestream_common();
+
+  void attach( int fd, int io_mode );
+  void open( const char *name, int io_mode );
+  void close();
+
+protected:
+  gzfilestream_common();
+
+private:
+  gzfilebuf *rdbuf();
+
+  gzfilebuf buffer;
+
+};
+
+class gzifstream : public gzfilestream_common, public istream {
+
+public:
+
+  gzifstream();
+  gzifstream( const char *name, int io_mode = ios::in );
+  gzifstream( int fd, int io_mode = ios::in );
+
+  virtual ~gzifstream();
+
+};
+
+class gzofstream : public gzfilestream_common, public ostream {
+
+public:
+
+  gzofstream();
+  gzofstream( const char *name, int io_mode = ios::out );
+  gzofstream( int fd, int io_mode = ios::out );
+
+  virtual ~gzofstream();
+
+};
+
+template<class T> class gzomanip {
+  friend gzofstream &operator<<(gzofstream &, const gzomanip<T> &);
+public:
+  gzomanip(gzofstream &(*f)(gzofstream &, T), T v) : func(f), val(v) { }
+private:
+  gzofstream &(*func)(gzofstream &, T);
+  T val;
+};
+
+template<class T> gzofstream &operator<<(gzofstream &s, const gzomanip<T> &m)
+{
+  return (*m.func)(s, m.val);
+}
+
+inline gzofstream &setcompressionlevel( gzofstream &s, int l )
+{
+  (s.rdbuf())->setcompressionlevel(l);
+  return s;
+}
+
+inline gzofstream &setcompressionstrategy( gzofstream &s, int l )
+{
+  (s.rdbuf())->setcompressionstrategy(l);
+  return s;
+}
+
+inline gzomanip<int> setcompressionlevel(int l)
+{
+  return gzomanip<int>(&setcompressionlevel,l);
+}
+
+inline gzomanip<int> setcompressionstrategy(int l)
+{
+  return gzomanip<int>(&setcompressionstrategy,l);
+}
+
+#endif