commit f927a3047c84be70387c0292f93d02aeb357f304
Author:     ManoloFLTK <41016272+ManoloFLTK@users.noreply.github.com>
AuthorDate: Thu Aug 18 08:53:19 2022 +0200
Commit:     ManoloFLTK <41016272+ManoloFLTK@users.noreply.github.com>
CommitDate: Thu Aug 18 08:53:19 2022 +0200

    Simplify class Fl_OpenGL_Display_Device.

 src/Fl_Device.cxx                               |  1 +
 src/Fl_Gl_Device_Plugin.cxx                     |  9 ++--
 src/Fl_Gl_Window.cxx                            | 47 ++++++++++++++++++-
 src/drivers/OpenGL/Fl_OpenGL_Display_Device.H   |  5 +-
 src/drivers/OpenGL/Fl_OpenGL_Display_Device.cxx | 61 +------------------------
 5 files changed, 53 insertions(+), 70 deletions(-)

diff --git src/Fl_Device.cxx src/Fl_Device.cxx
index c0ca99b..c4f1dec 100644
--- src/Fl_Device.cxx
+++ src/Fl_Device.cxx
@@ -24,6 +24,7 @@
   +- Fl_Surface_Device: any kind of surface that we can draw onto -> uses an Fl_Graphics_Driver
       |
       +- Fl_Display_Device: some kind of video device (one object per app)
+      +- Fl_OpenGL_Display_Device: supports adding FLTK child widgets to an Fl_Gl_Window
       +- Fl_Widget_Surface: any FLTK widget can be drawn to it
           |
           +- Fl_Copy_Surface: draw into the clipboard (in vectorial form if the platform supports it)
diff --git src/Fl_Gl_Device_Plugin.cxx src/Fl_Gl_Device_Plugin.cxx
index 79188ed..6abdbb5 100644
--- src/Fl_Gl_Device_Plugin.cxx
+++ src/Fl_Gl_Device_Plugin.cxx
@@ -1,7 +1,7 @@
 //
 // implementation of class Fl_Gl_Device_Plugin for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 2010-2016 by Bill Spitzak and others.
+// Copyright 2010-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -17,7 +17,8 @@
 #include <config.h>
 #include <FL/Fl_Gl_Window.H>
 #include <FL/Fl_RGB_Image.H>
-#include "drivers/OpenGL/Fl_OpenGL_Display_Device.H"
+#include <FL/Fl_Device.H>
+#include "Fl_Gl_Window_Driver.H"
 
 
 /**
@@ -31,7 +32,7 @@ public:
   virtual int print(Fl_Widget *w) {
     Fl_Gl_Window *glw = w->as_gl_window();
     if (!glw) return 0;
-    Fl_RGB_Image *img = Fl_OpenGL_Display_Device::capture_gl_rectangle(glw, 0, 0, glw->w(), glw->h());
+    Fl_RGB_Image *img =  Fl_Gl_Window_Driver::driver(glw)->capture_gl_rectangle(0, 0, glw->w(), glw->h());
     img->scale(glw->w(), glw->h());
     img->draw(0, 0);
     delete img;
@@ -40,7 +41,7 @@ public:
   virtual Fl_RGB_Image* rectangle_capture(Fl_Widget *widget, int x, int y, int w, int h) {
     Fl_Gl_Window *glw = widget->as_gl_window();
     if (!glw) return NULL;
-    return Fl_OpenGL_Display_Device::capture_gl_rectangle(glw, x, y, w, h);
+    return Fl_Gl_Window_Driver::driver(glw)->capture_gl_rectangle(x, y, w, h);
   }
 };
 
diff --git src/Fl_Gl_Window.cxx src/Fl_Gl_Window.cxx
index f0e608c..c5cda4a 100644
--- src/Fl_Gl_Window.cxx
+++ src/Fl_Gl_Window.cxx
@@ -1,7 +1,7 @@
 //
 // OpenGL window code for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2021 by Bill Spitzak and others.
+// Copyright 1998-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -341,7 +341,7 @@ void Fl_Gl_Window::draw_overlay() {}
 
 void Fl_Gl_Window::draw_begin() {
   Fl_Surface_Device::push_current( Fl_OpenGL_Display_Device::display_device() );
-  Fl_OpenGL_Graphics_Driver *drv = (Fl_OpenGL_Graphics_Driver*)fl_graphics_driver;
+  Fl_OpenGL_Graphics_Driver *drv = (Fl_OpenGL_Graphics_Driver*)Fl_Surface_Device::surface()->driver();
   drv->pixels_per_unit_ = pixels_per_unit();
 
   if (!valid()) {
@@ -543,6 +543,49 @@ Fl_Font_Descriptor** Fl_Gl_Window_Driver::fontnum_to_fontdescriptor(int fnum) {
   return &(fl_fonts[fnum].first);
 }
 
+/* Captures a rectangle of a Fl_Gl_Window and returns it as an RGB image.
+ This is the platform-independent version. Some platforms may override it.
+ */
+Fl_RGB_Image* Fl_Gl_Window_Driver::capture_gl_rectangle(int x, int y, int w, int h)
+{
+  Fl_Gl_Window *glw = pWindow;
+  glw->flush(); // forces a GL redraw, necessary for the glpuzzle demo
+  // Read OpenGL context pixels directly.
+  // For extra safety, save & restore OpenGL states that are changed
+  glPushClientAttrib(GL_CLIENT_PIXEL_STORE_BIT);
+  glPixelStorei(GL_PACK_ALIGNMENT, 4); /* Force 4-byte alignment */
+  glPixelStorei(GL_PACK_ROW_LENGTH, 0);
+  glPixelStorei(GL_PACK_SKIP_ROWS, 0);
+  glPixelStorei(GL_PACK_SKIP_PIXELS, 0);
+  //
+  float s = glw->pixels_per_unit();
+  if (s != 1) {
+    x = int(x * s); y = int(y * s); w = int(w * s); h = int(h * s);
+  }
+  // Read a block of pixels from the frame buffer
+  int mByteWidth = w * 3;
+  mByteWidth = (mByteWidth + 3) & ~3;    // Align to 4 bytes
+  uchar *baseAddress = new uchar[mByteWidth * h];
+  glReadPixels(x, glw->pixel_h() - (y+h), w, h,
+               GL_RGB, GL_UNSIGNED_BYTE,
+               baseAddress);
+  glPopClientAttrib();
+  // GL gives a bottom-to-top image, convert it to top-to-bottom
+  uchar *tmp = new uchar[mByteWidth];
+  uchar *p = baseAddress ;
+  uchar *q = baseAddress + (h-1)*mByteWidth;
+  for (int i = 0; i < h/2; i++, p += mByteWidth, q -= mByteWidth) {
+    memcpy(tmp, p, mByteWidth);
+    memcpy(p, q, mByteWidth);
+    memcpy(q, tmp, mByteWidth);
+  }
+  delete[] tmp;
+
+  Fl_RGB_Image *img = new Fl_RGB_Image(baseAddress, w, h, 3, mByteWidth);
+  img->alloc_array = 1;
+  return img;
+}
+
 /**
  \}
  \endcond
diff --git src/drivers/OpenGL/Fl_OpenGL_Display_Device.H src/drivers/OpenGL/Fl_OpenGL_Display_Device.H
index 8e6d1c8..2245ee9 100644
--- src/drivers/OpenGL/Fl_OpenGL_Display_Device.H
+++ src/drivers/OpenGL/Fl_OpenGL_Display_Device.H
@@ -1,7 +1,7 @@
 //
 // Definition of class Fl_OpenGL_Display_Device for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 2010-2016 by Bill Spitzak and others.
+// Copyright 2010-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -17,8 +17,6 @@
 #include <FL/Fl_Device.H>
 
 class Fl_OpenGL_Graphics_Driver;
-class Fl_Gl_Window;
-class Fl_RGB_Image;
 
 /**
  OpenGL Surface.
@@ -28,5 +26,4 @@ class FL_EXPORT Fl_OpenGL_Display_Device : public Fl_Surface_Device {
   Fl_OpenGL_Display_Device(Fl_OpenGL_Graphics_Driver *graphics_driver);
 public:
   static Fl_OpenGL_Display_Device *display_device();
-  static Fl_RGB_Image* capture_gl_rectangle(Fl_Gl_Window*, int, int, int, int);
 };
diff --git src/drivers/OpenGL/Fl_OpenGL_Display_Device.cxx src/drivers/OpenGL/Fl_OpenGL_Display_Device.cxx
index 1d0b25c..007408a 100644
--- src/drivers/OpenGL/Fl_OpenGL_Display_Device.cxx
+++ src/drivers/OpenGL/Fl_OpenGL_Display_Device.cxx
@@ -1,7 +1,7 @@
 //
 // implementation of class Fl_OpenGL_Display_Device for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 2010-2017 by Bill Spitzak and others.
+// Copyright 2010-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -14,20 +14,9 @@
 //     https://www.fltk.org/bugs.php
 //
 
-#include <config.h>
-#include <FL/Fl_Gl_Window.H>
-#include "../../Fl_Gl_Window_Driver.H"
-#include <FL/Fl_Image.H>
-#include "../../Fl_Screen_Driver.H"
-#include "../../Fl_Window_Driver.H"
-#include <FL/gl.h>
-#include <string.h>
-
 #include "Fl_OpenGL_Graphics_Driver.H"
 #include "Fl_OpenGL_Display_Device.H"
 
-// TODO: much of Fl_Gl_Choice should probably go here
-
 Fl_OpenGL_Display_Device *Fl_OpenGL_Display_Device::display_device() {
   static Fl_OpenGL_Display_Device *display = new Fl_OpenGL_Display_Device(new Fl_OpenGL_Graphics_Driver());
   return display;
@@ -37,51 +26,3 @@ Fl_OpenGL_Display_Device::Fl_OpenGL_Display_Device(Fl_OpenGL_Graphics_Driver *gr
 : Fl_Surface_Device(graphics_driver)
 {
 }
-
-Fl_RGB_Image* Fl_OpenGL_Display_Device::capture_gl_rectangle(Fl_Gl_Window* glw, int x, int y, int w, int h)
-{
-  return Fl_Gl_Window_Driver::driver(glw)->capture_gl_rectangle(x, y, w, h);
-}
-
-/* Captures a rectangle of a Fl_Gl_Window and returns it as a RGB image.
- This is the platform-independent version. Some platforms may re-implement it.
- */
-Fl_RGB_Image* Fl_Gl_Window_Driver::capture_gl_rectangle(int x, int y, int w, int h)
-{
-  Fl_Gl_Window *glw = pWindow;
-  glw->flush(); // forces a GL redraw, necessary for the glpuzzle demo
-  // Read OpenGL context pixels directly.
-  // For extra safety, save & restore OpenGL states that are changed
-  glPushClientAttrib(GL_CLIENT_PIXEL_STORE_BIT);
-  glPixelStorei(GL_PACK_ALIGNMENT, 4); /* Force 4-byte alignment */
-  glPixelStorei(GL_PACK_ROW_LENGTH, 0);
-  glPixelStorei(GL_PACK_SKIP_ROWS, 0);
-  glPixelStorei(GL_PACK_SKIP_PIXELS, 0);
-  //
-  float s = glw->pixels_per_unit();
-  if (s != 1) {
-    x = int(x * s); y = int(y * s); w = int(w * s); h = int(h * s);
-  }
-  // Read a block of pixels from the frame buffer
-  int mByteWidth = w * 3;
-  mByteWidth = (mByteWidth + 3) & ~3;    // Align to 4 bytes
-  uchar *baseAddress = new uchar[mByteWidth * h];
-  glReadPixels(x, glw->pixel_h() - (y+h), w, h,
-               GL_RGB, GL_UNSIGNED_BYTE,
-               baseAddress);
-  glPopClientAttrib();
-  // GL gives a bottom-to-top image, convert it to top-to-bottom
-  uchar *tmp = new uchar[mByteWidth];
-  uchar *p = baseAddress ;
-  uchar *q = baseAddress + (h-1)*mByteWidth;
-  for (int i = 0; i < h/2; i++, p += mByteWidth, q -= mByteWidth) {
-    memcpy(tmp, p, mByteWidth);
-    memcpy(p, q, mByteWidth);
-    memcpy(q, tmp, mByteWidth);
-  }
-  delete[] tmp;
-
-  Fl_RGB_Image *img = new Fl_RGB_Image(baseAddress, w, h, 3, mByteWidth);
-  img->alloc_array = 1;
-  return img;
-}