Include a stripped-down version of FLTK in tree and add a USE_INCLUDED_FLTK option to build against it.


git-svn-id: svn://svn.code.sf.net/p/tigervnc/code/trunk@4603 3789f03b-4d11-0410-bbf8-ca57d06f2519
diff --git a/common/fltk/src/Fl_Double_Window.cxx b/common/fltk/src/Fl_Double_Window.cxx
new file mode 100644
index 0000000..927eccb
--- /dev/null
+++ b/common/fltk/src/Fl_Double_Window.cxx
@@ -0,0 +1,462 @@
+//
+// "$Id: Fl_Double_Window.cxx 8383 2011-02-06 12:20:16Z AlbrechtS $"
+//
+// Double-buffered window code for the Fast Light Tool Kit (FLTK).
+//
+// Copyright 1998-2010 by Bill Spitzak and others.
+//
+// This library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Library General Public
+// License as published by the Free Software Foundation; either
+// version 2 of the License, or (at your option) any later version.
+//
+// This library is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+// Library General Public License for more details.
+//
+// You should have received a copy of the GNU Library General Public
+// License along with this library; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+// USA.
+//
+// Please report all bugs and problems on the following page:
+//
+//     http://www.fltk.org/str.php
+//
+
+#include <config.h>
+#include <FL/Fl.H>
+#include <FL/Fl_Double_Window.H>
+#include <FL/Fl_Printer.H>
+#include <FL/x.H>
+#include <FL/fl_draw.H>
+
+// On systems that support double buffering "naturally" the base
+// Fl_Window class will probably do double-buffer and this subclass
+// does nothing.
+
+#if USE_XDBE
+
+#include <X11/extensions/Xdbe.h>
+
+static int use_xdbe;
+
+static int can_xdbe() {
+  static int tried;
+  if (!tried) {
+    tried = 1;
+    int event_base, error_base;
+    if (!XdbeQueryExtension(fl_display, &event_base, &error_base)) return 0;
+    Drawable root = RootWindow(fl_display,fl_screen);
+    int numscreens = 1;
+    XdbeScreenVisualInfo *a = XdbeGetVisualInfo(fl_display,&root,&numscreens);
+    if (!a) return 0;
+    for (int j = 0; j < a->count; j++) {
+      if (a->visinfo[j].visual == fl_visual->visualid
+	  /*&& a->visinfo[j].perflevel > 0*/) {
+        use_xdbe = 1; break;
+      }
+    }
+    XdbeFreeVisualInfo(a);
+  }
+  return use_xdbe;
+}
+#endif
+
+void Fl_Double_Window::show() {
+  Fl_Window::show();
+}
+
+static void fl_copy_offscreen_to_display(int x, int y, int w, int h, Fl_Offscreen pixmap, int srcx, int srcy);
+
+/** \addtogroup fl_drawings
+ @{
+ */
+/** Copy a rectangular area of the given offscreen buffer into the current drawing destination.
+ \param x,y	position where to draw the copied rectangle
+ \param w,h	size of the copied rectangle
+ \param pixmap  offscreen buffer containing the rectangle to copy
+ \param srcx,srcy origin in offscreen buffer of rectangle to copy
+ */
+void fl_copy_offscreen(int x, int y, int w, int h, Fl_Offscreen pixmap, int srcx, int srcy) {
+  if (fl_graphics_driver == Fl_Display_Device::display_device()->driver()) {
+    fl_copy_offscreen_to_display(x, y, w, h, pixmap, srcx, srcy);
+  }
+  else { // when copy is not to the display
+    fl_begin_offscreen(pixmap);
+    uchar *img = fl_read_image(NULL, srcx, srcy, w, h, 0);
+    fl_end_offscreen();
+    fl_draw_image(img, x, y, w, h, 3, 0);
+    delete[] img;
+  }
+}
+/** @} */
+
+#if defined(USE_X11)
+
+static void fl_copy_offscreen_to_display(int x, int y, int w, int h, Fl_Offscreen pixmap, int srcx, int srcy) {
+  XCopyArea(fl_display, pixmap, fl_window, fl_gc, srcx, srcy, w, h, x, y);
+}
+
+
+// maybe someone feels inclined to implement alpha blending on X11?
+char fl_can_do_alpha_blending() {
+  return 0;
+}
+#elif defined(WIN32)
+
+// Code used to switch output to an off-screen window.  See macros in
+// win32.H which save the old state in local variables.
+
+typedef struct { BYTE a; BYTE b; BYTE c; BYTE d; } FL_BLENDFUNCTION;
+typedef BOOL (WINAPI* fl_alpha_blend_func)
+    (HDC,int,int,int,int,HDC,int,int,int,int,FL_BLENDFUNCTION);
+static fl_alpha_blend_func fl_alpha_blend = NULL;
+static FL_BLENDFUNCTION blendfunc = { 0, 0, 255, 1};
+
+/*
+ * This function checks if the version of MSWindows that we
+ * curently run on supports alpha blending for bitmap transfers
+ * and finds the required function if so.
+ */
+char fl_can_do_alpha_blending() {
+  static char been_here = 0;
+  static char can_do = 0;
+  // do this test only once
+  if (been_here) return can_do;
+  been_here = 1;
+  // load the library that implements alpha blending
+  HMODULE hMod = LoadLibrary("MSIMG32.DLL");
+  // give up if that doesn't exist (Win95?)
+  if (!hMod) return 0;
+  // now find the blending function inside that dll
+  fl_alpha_blend = (fl_alpha_blend_func)GetProcAddress(hMod, "AlphaBlend");
+  // give up if we can't find it (Win95)
+  if (!fl_alpha_blend) return 0;
+  // we have the call, but does our display support alpha blending?
+  // get the desktop's device context
+  HDC dc = GetDC(0L);
+  if (!dc) return 0;
+  // check the device capabilities flags. However GetDeviceCaps
+  // does not return anything useful, so we have to do it manually:
+
+  HBITMAP bm = CreateCompatibleBitmap(dc, 1, 1);
+  HDC new_gc = CreateCompatibleDC(dc);
+  int save = SaveDC(new_gc);
+  SelectObject(new_gc, bm);
+  /*COLORREF set = */ SetPixel(new_gc, 0, 0, 0x01010101);
+  BOOL alpha_ok = fl_alpha_blend(dc, 0, 0, 1, 1, new_gc, 0, 0, 1, 1, blendfunc);
+  RestoreDC(new_gc, save);
+  DeleteDC(new_gc);
+  DeleteObject(bm);
+  ReleaseDC(0L, dc);
+
+  if (alpha_ok) can_do = 1;
+  return can_do;
+}
+
+HDC fl_makeDC(HBITMAP bitmap) {
+  HDC new_gc = CreateCompatibleDC(fl_gc);
+  SetTextAlign(new_gc, TA_BASELINE|TA_LEFT);
+  SetBkMode(new_gc, TRANSPARENT);
+#if USE_COLORMAP
+  if (fl_palette) SelectPalette(new_gc, fl_palette, FALSE);
+#endif
+  SelectObject(new_gc, bitmap);
+  return new_gc;
+}
+
+static void fl_copy_offscreen_to_display(int x,int y,int w,int h,HBITMAP bitmap,int srcx,int srcy) {
+  HDC new_gc = CreateCompatibleDC(fl_gc);
+  int save = SaveDC(new_gc);
+  SelectObject(new_gc, bitmap);
+  BitBlt(fl_gc, x, y, w, h, new_gc, srcx, srcy, SRCCOPY);
+  RestoreDC(new_gc, save);
+  DeleteDC(new_gc);
+}
+
+void fl_copy_offscreen_with_alpha(int x,int y,int w,int h,HBITMAP bitmap,int srcx,int srcy) {
+  HDC new_gc = CreateCompatibleDC(fl_gc);
+  int save = SaveDC(new_gc);
+  SelectObject(new_gc, bitmap);
+  BOOL alpha_ok = 0;
+  // first try to alpha blend
+  // if to printer, always try alpha_blend
+  int to_display = Fl_Surface_Device::surface()->class_name() == Fl_Display_Device::class_id; // true iff display output
+  if ( (to_display && fl_can_do_alpha_blending()) || Fl_Surface_Device::surface()->class_name() == Fl_Printer::class_id) {
+    alpha_ok = fl_alpha_blend(fl_gc, x, y, w, h, new_gc, srcx, srcy, w, h, blendfunc);
+  }
+  // if that failed (it shouldn't), still copy the bitmap over, but now alpha is 1
+  if (!alpha_ok) {
+    BitBlt(fl_gc, x, y, w, h, new_gc, srcx, srcy, SRCCOPY);
+  }
+  RestoreDC(new_gc, save);
+  DeleteDC(new_gc);
+}
+
+extern void fl_restore_clip();
+
+#elif defined(__APPLE_QUARTZ__) || defined(FL_DOXYGEN)
+
+char fl_can_do_alpha_blending() {
+  return 1;
+}
+
+Fl_Offscreen fl_create_offscreen_with_alpha(int w, int h) {
+  void *data = calloc(w*h,4);
+  CGColorSpaceRef lut = CGColorSpaceCreateDeviceRGB();
+  CGContextRef ctx = CGBitmapContextCreate(
+    data, w, h, 8, w*4, lut, kCGImageAlphaPremultipliedLast);
+  CGColorSpaceRelease(lut);
+  return (Fl_Offscreen)ctx;
+}
+
+/** \addtogroup fl_drawings
+ @{
+ */
+
+/** 
+  Creation of an offscreen graphics buffer.
+ \param w,h     width and height in pixels of the buffer.
+ \return    the created graphics buffer.
+ */
+Fl_Offscreen fl_create_offscreen(int w, int h) {
+  void *data = calloc(w*h,4);
+  CGColorSpaceRef lut = CGColorSpaceCreateDeviceRGB();
+  CGContextRef ctx = CGBitmapContextCreate(
+    data, w, h, 8, w*4, lut, kCGImageAlphaNoneSkipLast);
+  CGColorSpaceRelease(lut);
+  return (Fl_Offscreen)ctx;
+}
+
+static void bmProviderRelease (void *src, const void *data, size_t size) {
+  CFIndex count = CFGetRetainCount(src);
+  CFRelease(src);
+  if(count == 1) free((void*)data);
+}
+
+static void fl_copy_offscreen_to_display(int x,int y,int w,int h,Fl_Offscreen osrc,int srcx,int srcy) {
+  CGContextRef src = (CGContextRef)osrc;
+  void *data = CGBitmapContextGetData(src);
+  int sw = CGBitmapContextGetWidth(src);
+  int sh = CGBitmapContextGetHeight(src);
+  CGImageAlphaInfo alpha = CGBitmapContextGetAlphaInfo(src);
+  CGColorSpaceRef lut = CGColorSpaceCreateDeviceRGB();
+  // when output goes to a Quartz printercontext, release of the bitmap must be
+  // delayed after the end of the print page
+  CFRetain(src);
+  CGDataProviderRef src_bytes = CGDataProviderCreateWithData( src, data, sw*sh*4, bmProviderRelease);
+  CGImageRef img = CGImageCreate( sw, sh, 8, 4*8, 4*sw, lut, alpha,
+    src_bytes, 0L, false, kCGRenderingIntentDefault);
+  // fl_push_clip();
+  CGRect rect = { { x, y }, { w, h } };
+  Fl_X::q_begin_image(rect, srcx, srcy, sw, sh);
+  CGContextDrawImage(fl_gc, rect, img);
+  Fl_X::q_end_image();
+  CGImageRelease(img);
+  CGColorSpaceRelease(lut);
+  CGDataProviderRelease(src_bytes);
+}
+
+/**  Deletion of an offscreen graphics buffer.
+ \param ctx     the buffer to be deleted.
+ */
+void fl_delete_offscreen(Fl_Offscreen ctx) {
+  if (!ctx) return;
+  void *data = CGBitmapContextGetData((CGContextRef)ctx);
+  CFIndex count = CFGetRetainCount(ctx);
+  CGContextRelease((CGContextRef)ctx);
+  if(count == 1) free(data);
+}
+
+const int stack_max = 16;
+static int stack_ix = 0;
+static CGContextRef stack_gc[stack_max];
+static Window stack_window[stack_max];
+static Fl_Surface_Device *_ss;
+
+/**  Send all subsequent drawing commands to this offscreen buffer.
+ \param ctx     the offscreen buffer.
+ */
+void fl_begin_offscreen(Fl_Offscreen ctx) {
+  _ss = Fl_Surface_Device::surface(); 
+  Fl_Display_Device::display_device()->set_current();
+  if (stack_ix<stack_max) {
+    stack_gc[stack_ix] = fl_gc;
+    stack_window[stack_ix] = fl_window;
+  } else 
+    fprintf(stderr, "FLTK CGContext Stack overflow error\n");
+  stack_ix++;
+
+  fl_gc = (CGContextRef)ctx;
+  fl_window = 0;
+  CGContextSaveGState(fl_gc);
+  fl_push_no_clip();
+}
+
+/** Quit sending drawing commands to the current offscreen buffer.
+ */
+void fl_end_offscreen() {
+  Fl_X::q_release_context();
+  fl_pop_clip();
+  if (stack_ix>0)
+    stack_ix--;
+  else
+    fprintf(stderr, "FLTK CGContext Stack underflow error\n");
+  if (stack_ix<stack_max) {
+    fl_gc = stack_gc[stack_ix];
+    fl_window = stack_window[stack_ix];
+  }
+  _ss->set_current();
+}
+
+/** @} */
+
+extern void fl_restore_clip();
+
+#else
+# error unsupported platform
+#endif
+
+/**
+  Forces the window to be redrawn.
+*/
+void Fl_Double_Window::flush() {flush(0);}
+
+/**
+  Forces the window to be redrawn.
+  \param[in] eraseoverlay non-zero to erase overlay, zero to ignore
+
+  Fl_Overlay_Window relies on flush(1) copying the back buffer to the
+  front everywhere, even if damage() == 0, thus erasing the overlay,
+  and leaving the clip region set to the entire window.
+*/
+void Fl_Double_Window::flush(int eraseoverlay) {
+  make_current(); // make sure fl_gc is non-zero
+  Fl_X *myi = Fl_X::i(this);
+  if (!myi->other_xid) {
+#if USE_XDBE
+    if (can_xdbe()) {
+      myi->other_xid = XdbeAllocateBackBufferName(fl_display, fl_xid(this), XdbeCopied);
+      myi->backbuffer_bad = 1;
+    } else
+#endif
+#if defined(USE_X11) || defined(WIN32)
+    myi->other_xid = fl_create_offscreen(w(), h());
+    clear_damage(FL_DAMAGE_ALL);
+#elif defined(__APPLE_QUARTZ__)
+    if (force_doublebuffering_) {
+      myi->other_xid = fl_create_offscreen(w(), h());
+      clear_damage(FL_DAMAGE_ALL);
+    }
+#else
+# error unsupported platform
+#endif
+  }
+#if USE_XDBE
+  if (use_xdbe) {
+    if (myi->backbuffer_bad || eraseoverlay) {
+      // Make sure we do a complete redraw...
+      if (myi->region) {XDestroyRegion(myi->region); myi->region = 0;}
+      clear_damage(FL_DAMAGE_ALL);
+      myi->backbuffer_bad = 0;
+    }
+
+    // Redraw as needed...
+    if (damage()) {
+      fl_clip_region(myi->region); myi->region = 0;
+      fl_window = myi->other_xid;
+      draw();
+      fl_window = myi->xid;
+    }
+
+    // Copy contents of back buffer to window...
+    XdbeSwapInfo s;
+    s.swap_window = fl_xid(this);
+    s.swap_action = XdbeCopied;
+    XdbeSwapBuffers(fl_display, &s, 1);
+    return;
+  } else
+#endif
+  if (damage() & ~FL_DAMAGE_EXPOSE) {
+    fl_clip_region(myi->region); myi->region = 0;
+#ifdef WIN32
+    HDC _sgc = fl_gc;
+    fl_gc = fl_makeDC(myi->other_xid);
+    int save = SaveDC(fl_gc);
+    fl_restore_clip(); // duplicate region into new gc
+    draw();
+    RestoreDC(fl_gc, save);
+    DeleteDC(fl_gc);
+    fl_gc = _sgc;
+    //# if defined(FLTK_USE_CAIRO)
+    //if Fl::cairo_autolink_context() Fl::cairo_make_current(this); // capture gc changes automatically to update the cairo context adequately
+    //# endif
+#elif defined(__APPLE__)
+    if ( myi->other_xid ) {
+      fl_begin_offscreen( myi->other_xid );
+      fl_clip_region( 0 );   
+      draw();
+      fl_end_offscreen();
+    } else {
+      draw();
+    }
+#else // X:
+    fl_window = myi->other_xid;
+    draw();
+    fl_window = myi->xid;
+#endif
+  }
+  if (eraseoverlay) fl_clip_region(0);
+  // on Irix (at least) it is faster to reduce the area copied to
+  // the current clip region:
+  int X,Y,W,H; fl_clip_box(0,0,w(),h(),X,Y,W,H);
+  if (myi->other_xid) fl_copy_offscreen(X, Y, W, H, myi->other_xid, X, Y);
+}
+
+void Fl_Double_Window::resize(int X,int Y,int W,int H) {
+  int ow = w();
+  int oh = h();
+  Fl_Window::resize(X,Y,W,H);
+#if USE_XDBE
+  if (use_xdbe) {
+    Fl_X* myi = Fl_X::i(this);
+    if (myi && myi->other_xid && (ow < w() || oh < h())) {
+      // STR #2152: Deallocate the back buffer to force creation of a new one.
+      XdbeDeallocateBackBufferName(fl_display,myi->other_xid);
+      myi->other_xid = 0;
+    }
+    return;
+  }
+#endif
+  Fl_X* myi = Fl_X::i(this);
+  if (myi && myi->other_xid && (ow != w() || oh != h())) {
+    fl_delete_offscreen(myi->other_xid);
+    myi->other_xid = 0;
+  }
+}
+
+void Fl_Double_Window::hide() {
+  Fl_X* myi = Fl_X::i(this);
+  if (myi && myi->other_xid) {
+#if USE_XDBE
+    if (!use_xdbe)
+#endif
+      fl_delete_offscreen(myi->other_xid);
+  }
+  Fl_Window::hide();
+}
+
+/**
+  The destructor <I>also deletes all the children</I>. This allows a
+  whole tree to be deleted at once, without having to keep a pointer to
+  all the children in the user code.
+*/
+Fl_Double_Window::~Fl_Double_Window() {
+  hide();
+}
+
+//
+// End of "$Id: Fl_Double_Window.cxx 8383 2011-02-06 12:20:16Z AlbrechtS $".
+//