NX Graphics Subsystem

Last Updated: December 5, 2008

1.0 Introduction

1.1 Overview
1.2 Objectives
1.3 Organization

1.3.1 NX Graphics Library (NXGL)

1.3.2 NX (NXSU and NXMU)

1.3.3 NX Tool Kit (NXTK)

1.3.4 NX Fonts Support (NXFONTS)

1.3.5 NX Widgets (NXWIDGETS)

2.0 NX User APIs

2.1 NX Header Files
2.2 NX Graphics Library (NXGL)

2.2.1 NXGL Types

2.2.1 nxgl_rgb2yuv()

2.2.2 nxgl_yuv2rgb()

2.2.3 nxgl_rectcopy()

2.2.4 nxgl_rectoffset()

2.2.5 nxgl_vectoradd()

2.2.6 nxgl_vectorsubtract()

2.2.7 nxgl_rectintersect()

2.2.8 nxgl_rectunion()

2.2.9 nxgl_nonintersecting()

2.2.10 nxgl_rectoverlap()

2.2.11 nxgl_rectinside()

2.2.12 nxgl_rectsize()

2.2.13 nxgl_nullrect()

2.2.14 nxgl_runoffset()

2.2.15 nxgl_runcopy()

2.2.16 nxgl_trapoffset()

2.2.17 nxgl_trapcopy()

2.2.18 nxgl_colorcopy

2.3 NX

2.3.1 Pre-Processor Definitions

2.3.2 NX Types

2.3.3 NX Server Callbacks

2.3.3.1 redraw()

2.3.3.2 position()

2.3.3.3 mousein()

2.3.3.4 kbdin()

2.3.4 nx_runinstance() (and nx_run() macro)2.3.5 nx_connectinstance() (and nx_connect() macro) 2.3.6 nx_open() 2.3.7 nx_disconnect() 2.3.8 nx_close() 2.3.9 nx_eventhandler() 2.3.10 nx_eventnotify() 2.3.11 nx_openwindow() 2.3.12 nx_closewindow() 2.3.13 nx_requestbkgd() 2.3.14 nx_releasebkgd() 2.3.15 nx_getposition() 2.3.16 nx_setposition() 2.3.17 nx_setsize() 2.3.18 nx_raise() 2.3.19 nx_lower() 2.3.20 nx_fill() 2.3.21 nx_filltrapezoid() 2.3.22 nx_setbgcolor() 2.3.23 nx_move() 2.3.24 nx_bitmap() 2.3.25 nx_kbdin() 2.3.26 nx_mousein()

2.4 NX Tool Kit (NXTK)

2.4.1 NXTK Types()

2.4.2 nxtk_openwindow()

2.4.3 nxtk_closewindow()

2.4.4 nxtk_getposition()

2.4.5 nxtk_setposition()

2.4.6 nxtk_setsize()

2.4.7 nxtk_raise()

2.4.8 nxtk_lower()

2.4.9 nxtk_fillwindow()

2.4.10 nxtk_filltrapwindow()

2.4.11 nxtk_movewindow()

2.4.12 nxtk_bitmapwindow()

2.4.13 nxtk_opentoolbar()

2.4.14 nxtk_closetoolbar()

2.4.15 nxtk_filltoolbar()

2.4.16 nxtk_filltraptoolbar()

2.4.17 nxtk_movetoolbar()

2.4.18 nxtk_bitmaptoolbar()

2.5 NX Fonts Support (NXFONTS)

2.5.1 NXFONTS Types()

2.5.2 nxf_getfontset()

2.5.3 nxf_getbitmap()

2.5.4 nxf_convert_*bpp()

Appendix A graphics/ Directory Structure
Appendix B NX Configuration Options

B.1 General Configuration Settings

B.2 NXGL Configuration Settings

B.3 NX Configuration Settings

B.4 NX Multi-User (Only) Configuration Settings

B.5 NXTK Configuration Settings

B.6 NXFONTS Configuration Settings

Appendix C NX Test Coverage

1.0 Introduction

1.1 Overview

This document describes the tiny graphics support included in NuttX. It includes an overview description of that graphics support, detailed descriptions of the NuttX graphics APIs, and discussion of code organization, and OS configuration options.

Figure 1. This sceen shot shows the final frame for the NuttX example at examples/nx running on the simulated, Linux x86 platform with simulated framebuffer output to an X window. This picture shows to framed windows with (blank) toolbars. Each window has displayed text as received from the NX keyboard interface The second window has just been raised to the top of the display.

1.2 Objectives

The objective of this development was to provide a tiny windowing system in the spirit of X, but greatly scaled down and appropriate for most resource-limited embedded environments. The current NX implementation supports the general following, high-level features:

Virtual Vertical Graphics Space. Windows that reside in a virtual, vertical space so that it makes sense to talk about one window being on top of another and obcuring the window below it.
Client/Server Model. A standard client server/model was adopted. NX may be considered a server and other logic that presents the windows are NX clients.
Single- and Multi-User Support. NX includes front-end logic to either a simple single-thread/single-user architecture or a separate NX server thread that can serve multiple NX client threads. In the single-user case, the NX server is simply a set of library calls; in the multi-user case, NX is a server thread/daemon the serializes graphics operations from multiple clients. Other some unique start-up/connection logic, the APIs supported by the single-user and multi-user front-ends are identical. Providing both front-ends is consistent with the NuttX commitment to scalability.
Minimal Graphics Toolset. The actual implementation of the graphics operations is performed by common, back-end logic. This back-end supports only a primitive set of graphic and rendering operations.
Framebuffer Device Interface. NX supports any graphics device using the NuttX framebuffer driver interface. (However, the dependency of NX on framebuffer drivers is minimal and the logic could be extended to other interfaces -- such as a serial LCD -- with some minimal effort).
Transparent to NX Client. The window client on "sees" the sub-window that is operates in and does not need to be concerned with the virtual, vertical space (other that to respond to redraw requests from NX when needed).
Framed Windows and Toolbars. NX also adds the capability to support windows with frames and toolbars on top of the basic windowing support. These are windows such as those shown in the screenshot above. These framed windows sub-divide one one window into three relatively independent subwindows: A frame, the contained window and an (optional) toolbar window.
Mouse Support. NX provides support for a mouse or other X/Y pointing devices. APIs are provided to allow external devices to give X/Y position information and mouse button presses to NX. NX will then provide the mouse input to the relevant window clients via callbacks. Client windows only receive the mouse input callback if the mouse is positioned over a visible portion of the client window; X/Y position is provided to the client in the relative coordinate system of the client window.
Keyboard input. NX also supports keyboard/keypad devices. APIs are provided to allow external devices to give keypad information to NX. NX will then provide the mouse input to the top window on the display (the window that has the focus) via a callback function.

1.3 Organization

NX is organized into 6 (and perhaps someday 7 or 8) logical modules. These logical modules also correspond to the directory organization. That NuttX directory organization is discussed in Appendix B of this document. The logic modules are discussed in the following sub-paragraphs.

1.3.1 NX Graphics Library (`NXGL`)

NXGLIB is a standalone library that contains low-level graphics utilities and direct framebuffer rendering logic. NX is built on top NXGLIB.

1.3.2 NX (`NXSU` and `NXMU`)

NX is the tiny NuttX windowing system for raw windows (i.e., simple regions of graphics memory). NX includes both a small-footprint, single user implementaton (NXSU) and a somewhat larger multi-user implentation (NXMU as described below). Both conform to the same APIs as defined in include/nuttx/nx.h and, hence, are interchangable¹. NX can be used without NXWIDGETS and without NXTOOLKIT for raw window displays.

¹NXMU and NXSU are interchangeable other than (1) certain start-up and intialization APIs (as described below), and (2) timing. With NXSU, NX APIs execute immediately; with NXMU, NX APIs defer and serialize the operations and, hence, introduce different timing and potential race conditions that you would not experience with NXSU.

NXNULL? At one time, I also envisoned a NULL front-end that did not support windowing at all but, rather, simply provided the entire framebuffer memory as one dumb window. This has the advantage that the same NX APIs can be used on the one dumb window as for the other NX windows. This would be in the NuttX spirit of scalability.

However, the same end result can be obtained by using the nx_requestbkgd() API. It still may be possible to reduce the footprint in this usage case by developing and even thinner NXNULL front-end. That is a possible future development.

1.3.3 NX Tool Kit (`NXTK`)

NXTK is a s set of C graphics tools that provide higher-level window drawing operations. This is the module where the framed windows and toolbar logic is implemented. NXTK is built on top of NX and does not depend on NXWIDGETS.

1.3.4 NX Fonts Support (`NXFONTS`)

A set of C graphics tools for present (bitmap) font images. The font implementation is at a very low level or graphics operation, comparable to the logic in NXGLIB. NXFONTS does not depend on any NX module other than some utilities and types from NXGLIB.

1.3.5 NX Widgets (`NXWIDGETS`)

I had originally planned a high level, C++, object-oriented library for object-oriented access to graphics widgets. However, C++ compilers are not available for some of the targets supported by NuttX. So I have decided to implement the entire solution in C. That decision makes the solution somewhat more difficult to work with, but supports all platforms.

At this point, the amount of C in the implementation would make conversion to C++ a more difficult job. I leave the C++ widget interface to any contributor who may have an interest in such things.

2.0 NX User APIs

2.1 NX Header Files

include/nuttx/nxglib.h: Describes the NXGLIB C interfaces
include/nuttx/nx.h: Describes the NX C interfaces
include/nutt/nxtk.h: Describe the NXTOOLKIT C interfaces
include/nutt/nxfont.h: Describe sthe NXFONT C interfaces
include/nuttx/nxwidgets.h: Will describe the NXWIDGETS classes (no longer planned)



2.2 NX Graphics Library (NXGL)


  NXGL provides many APIs, some available for use internally by NX and
  others for use by applications as well.
  Only those APIs intended for application usage are documented here
  See include/nuttx/nxglib.h for the full set of APIs;
  those APIs might be of interest if you are rendering directly into
  framebuffer memory.


2.2.1 NXGL Types


  nxgl_mxpixel_t.
  Holds one device pixel.
  NXGLIB will select the smallest size for the nxgl_mxpixel_t
  that just contains the pixel:  byte if 16, 24, and 32 resolution
  support is disabled, uint16 if 24, and 32 resolution
  support is disabled, or uint32.



  nxgl_coord_t
  A given coordinate is limited to the screen height an width.  If either
  of those values exceed 32,767 pixels, then the following will have to need
  to change:

typedef sint16 nxgl_coord_t;



  struct nxgl_point_s. Describes a point on the display:

struct nxgl_point_s
{
  nxgl_coord_t x;         /* X position, range: 0 to screen width - 1 */
  nxgl_coord_t y;         /* Y position, range: 0 to screen height - 1 */
};



  struct nxgl_size_s. Describes the size of a rectangular region.

struct nxgl_size_s
{
  nxgl_coord_t w;        /* Width in pixels */
  nxgl_coord_t h;        /* Height in rows */
};



  struct nxgl_rect_s. Describes a positioned rectangle on the display.

struct nxgl_rect_s
{
  struct nxgl_point_s pt1; /* Upper, left-hand corner */
  struct nxgl_point_s pt2; /* Lower, right-hand corner */
};



  struct nxgl_run_s.
  Describes a run, i.e., a horizontal line.  Note that the start/end positions
  have fractional precision.  This is necessary for good joining of trapezoids
  when a more complex shape is decomposed into trapezoids

struct nxgl_run_s
{
  b16_t        x1;        /* Left X position, range: 0 to x2 */
  b16_t        x2;        /* Right X position, range: x1 to screen width - 1 */
  nxgl_coord_t y;         /* Top Y position, range: 0 to screen height - 1 */
};



  struct nxgl_trapezoid_s.
  Describes a horizontal trapezoid on the display in terms the run at the
  top of the trapezoid and the run at the bottom

struct nxgl_trapezoid_s
{
  struct nxgl_run_s top;  /* Top run */
  struct nxgl_run_s bot;  /* bottom run */
};


2.2.1 nxgl_rgb2yuv()
Function Prototype:
#include <nuttx/nxglib.h>
void nxgl_rgb2yuv(ubyte r, ubyte g, ubyte b, ubyte *y, ubyte *u, ubyte *v);


  Description:
  Convert 8-bit RGB triplet to 8-bit YUV triplet.


2.2.2 nxgl_yuv2rgb()
Function Prototype:
#include <nuttx/nxglib.h>
void nxgl_yuv2rgb(ubyte y, ubyte u, ubyte v, ubyte *r, ubyte *g, ubyte *b);


  Description:
  Convert 8-bit RGB triplet to 8-bit YUV triplet.


2.2.3 nxgl_rectcopy()
Function Prototype:
#include <nuttx/nxglib.h>
void nxgl_rectcopy(FAR struct nxgl_rect_s *dest,
                   FAR const struct nxgl_rect_s *src);


  Description:
  This is essentially memcpy()for rectangles.  We don't do structure
  assignments because some compilers are not good at that.


2.2.4 nxgl_rectoffset()
Function Prototype:
#include <nuttx/nxglib.h>
void nxgl_rectoffset(FAR struct nxgl_rect_s *dest,
                     FAR const struct nxgl_rect_s *src,
                     nxgl_coord_t dx, nxgl_coord_t dy);


  Description:
   Offset the rectangle position by the specified dx, dy values.


2.2.5 nxgl_vectoradd()
Function Prototype:
#include <nuttx/nxglib.h>
void nxgl_vectoradd(FAR struct nxgl_point_s *dest,
                    FAR const struct nxgl_point_s *v1,
                    FAR const struct nxgl_point_s *v2);


  Description:
  Add two 2x1 vectors and save the result to a third.


2.2.6 nxgl_vectorsubtract()
Function Prototype:
#include <nuttx/nxglib.h>
void nxgl_vectsubtract(FAR struct nxgl_point_s *dest,
                       FAR const struct nxgl_point_s *v1,
                       FAR const struct nxgl_point_s *v2);


  Description:
  Add subtract vector v2 from vector v1 and return the result in vector dest.


2.2.7 nxgl_rectintersect()
Function Prototype:
#include <nuttx/nxglib.h>
void nxgl_rectintersect(FAR struct nxgl_rect_s *dest,
                        FAR const struct nxgl_rect_s *src1,
                        FAR const struct nxgl_rect_s *src2);


  Description:
   Return the rectangle representing the intersection of the two rectangles.


2.2.8 nxgl_rectunion()
Function Prototype:
#include <nuttx/nxglib.h>
void nxgl_rectunion(FAR struct nxgl_rect_s *dest,
                    FAR const struct nxgl_rect_s *src1,
                    FAR const struct nxgl_rect_s *src2);


  Description:
  Given two rectanges, src1 and src2, return the larger rectangle that 
  contains both, dest.


2.2.9 nxgl_nonintersecting()
Function Prototype:
#include <nuttx/nxglib.h>
nxgl_nonintersecting(FAR struct nxgl_rect_s result[4],
                     FAR const struct nxgl_rect_s *rect1,
                     FAR const struct nxgl_rect_s *rect2);


  Description:
  Return the regions of rectangle rect1 that do not intersect with
  rect2.  This will four rectangles, some of which may be
  degenerate (and can be picked off with nxgl_nullrect()).


2.2.10 nxgl_rectoverlap()
Function Prototype:
#include <nuttx/nxglib.h>
boolean nxgl_rectoverlap(FAR struct nxgl_rect_s *rect1,
                         FAR struct nxgl_rect_s *rect2);


  Description:
  Return TRUE if the two rectangles overlap.


2.2.11 nxgl_rectinside()
Function Prototype:
#include <nuttx/nxglib.h>
boolean nxgl_rectinside(FAR const struct nxgl_rect_s *rect,
                        FAR const struct nxgl_point_s *pt);


  Description:
  Return TRUE if the point pt lies within rect.


2.2.12 nxgl_rectsize()
Function Prototype:
#include <nuttx/nxglib.h>
void nxgl_rectsize(FAR struct nxgl_size_s *size,
                   FAR const struct nxgl_rect_s *rect);


  Description:
  Return the size of the specified rectangle.


2.2.13 nxgl_nullrect()
Function Prototype:
#include <nuttx/nxglib.h>
boolean nxgl_nullrect(FAR const struct nxgl_rect_s *rect);


  Description:
   Return TRUE if the area of the retangle is <= 0.


2.2.14 nxgl_runoffset()
Function Prototype:
#include <nuttx/nxglib.h>
void nxgl_runoffset(FAR struct nxgl_run_s *dest,
                    FAR const struct nxgl_run_s *src,
                    nxgl_coord_t dx, nxgl_coord_t dy);


  Description:
  Offset the run position by the specified dx, dy values.


2.2.15 nxgl_runcopy()
Function Prototype:
#include <nuttx/nxglib.h>
void nxgl_runcopy(FAR struct nxgl_run_s *dest,
                  FAR const struct nxgl_run_s *src);


  Description:
  This is essentially memcpy()for runs.  We don't do structure assignments
  because some compilers are not good at that.


2.2.16 nxgl_trapoffset()
Function Prototype:
#include <nuttx/nxglib.h>
void nxgl_trapoffset(FAR struct nxgl_trapezoid_s *dest,
                     FAR const struct nxgl_trapezoid_s *src,
                     nxgl_coord_t dx, nxgl_coord_t dy);


  Description:
  Offset the trapezoid position by the specified dx, dy values.


2.2.1 nxgl_trapcopy()
Function Prototype:
#include <nuttx/nxglib.h>
void nxgl_trapcopy(FAR struct nxgl_trapezoid_s *dest,
                   FAR const struct nxgl_trapezoid_s *src);


  Description:
  This is essentially memcpy()for trapezoids.  We don't do structure
  assignments because some compilers are not good at that.


2.2.1 nxgl_colorcopy
Function Prototype:
#include <nuttx/nxglib.h>
nxgl_colorcopy(nxgl_mxpixel_t dest[CONFIG_NX_NPLANES],
               const nxgl_mxpixel_t src[CONFIG_NX_NPLANES]);


  Description:
  This is essentially memcpy()for colors.  This does very little for us
  other than hide all of the conditional compilation for planar colors
  in one place.


2.3 NX

2.3.1 Pre-Processor Definitions


  The default server message queue name used by the
  nx_run() macro:

#define NX_DEFAULT_SERVER_MQNAME "/dev/nxs"



  Mouse button bits:

#define NX_MOUSE_NOBUTTONS    0x00
#define NX_MOUSE_LEFTBUTTON   0x01
#define NX_MOUSE_CENTERBUTTON 0x02
#define NX_MOUSE_RIGHTBUTTON  0x04


2.3.2 NX Types


  The interface to the NX server is managed using a opaque handle:

typedef FAR void *NXHANDLE;



  The interface to a specific window is managed using an opaque handle:

typedef FAR void *NXWINDOW;



  These define callbacks that must be provided to
  nx_openwindow().
  In the multi-user model, these callbacks will be invoked as part of the
  processing performed by
  nx_eventhandler().

struct nx_callback_s
{
  void (*redraw)(NXWINDOW hwnd, FAR const struct nxgl_rect_s *rect,
                 boolean more, FAR void *arg);
  void (*position)(NXWINDOW hwnd, FAR const struct nxgl_size_s *size,
                   FAR const struct nxgl_point_s *pos,
                   FAR const struct nxgl_rect_s *bounds,
                   FAR void *arg);
#ifdef CONFIG_NX_MOUSE
  void (*mousein)(NXWINDOW hwnd, FAR const struct nxgl_point_s *pos,
                  ubyte buttons, FAR void *arg);
#endif
#ifdef CONFIG_NX_KBD
  void (*kbdin)(NXWINDOW hwnd, ubyte nch, FAR const ubyte *ch, FAR void *arg);
#endif
};


2.3.3 NX Server Callbacks

2.3.3.1 redraw()
Callback Function Prototype:
void redraw(NXWINDOW hwnd, FAR const struct nxgl_rect_s *rect,
            boolean more, FAR void *arg);


  Description:
  NX requests that the client re-draw the portion of the window within
  with rectangle.


  Input Parameters:
  

    hwnd
    
The handle created by nx_openwindow()
      or nx_requestbkgd()
    
rect
    
The rectangle that needs to be re-drawn (in window relative coordinates)
    
more
    
TRUE: More re-draw requests will follow
    
arg
    
User provided argument (see nx_openwindow())
  


  Returned Value: None


2.3.3.2 position()
Callback Function Prototype:
void position(NXWINDOW hwnd, FAR const struct nxgl_size_s *size,
              FAR const struct nxgl_point_s *pos,
              FAR const struct nxgl_rect_s *bounds,
              FAR void *arg);


  Description:
  The size or position of the window has changed (or the window was
  just created with zero size.


  Input Parameters:
  

    hwnd
    
The handle created by nx_openwindow()
      or nx_requestbkgd()
    
size
    
The size of the window
    
pos
    
The position of the upper left hand corner of the window on
      the overall display
    
bounds
    
The bounding rectangle that the describes the entire display
    
arg
    
User provided argument (see nx_openwindow())
  


  Returned Value: None


2.3.3.3 mousein()
Callback Function Prototype:
#ifdef CONFIG_NX_MOUSE
void mousein(NXWINDOW hwnd, FAR const struct nxgl_point_s *pos,
             ubyte buttons, FAR void *arg);
#endif


  Description:
  New mouse data is available for the window


  Input Parameters:
  

    hwnd
    
The handle created by nx_openwindow()
      or nx_requestbkgd()
    
pos
    
The (x,y) position of the mouse
    
buttons
    
See NX_MOUSE_* definitions
    
arg
    
User provided argument (see nx_openwindow())
  


  Returned Value: None


2.3.3.4 kbdin()
Callback Function Prototype:
#ifdef CONFIG_NX_KBD
void (*kbdin)(NXWINDOW hwnd, ubyte nch, FAR const ubyte *ch, FAR void *arg);
#endif


  Description:
  New keyboard/keypad data is available for the window.


  Input Parameters:
  

    hwnd
    
The handle created by nx_openwindow()
      or nx_requestbkgd()
    
nch
    
The number of characters that are available in ch[]
    
ch
    
The array of characters
    
arg
    
User provided argument (see nx_openwindow())
  


  Returned Value: NOne


2.3.4 nx_runinstance() (and nx_run() macro)

Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

#ifdef CONFIG_NX_MULTIUSER
int nx_runinstance(FAR const char *mqname, FAR struct fb_vtable_s *fb);
#define nx_run(fb) nx_runinstance(NX_DEFAULT_SERVER_MQNAME, fb)
#endif


  Description:
  This is the server entry point.  It does not return; the calling thread
  is dedicated to supporting NX server.


  NOTE that multiple instances of the NX server may run at the same time,
  with different callback and message queue names.  nx_run() is simply
  a macro that can be used when only one server instance is required.  In
  that case, a default server name is used.


  Multiple user mode only!


  Input Parameters:
  

    mqname
    

     - The name for the server incoming message queue
    
fb
    
Vtable "object" of the framebuffer "driver" to use
  


  Returned Value:
  This function usually does not return.  If it does return, it will
  return ERROR and errno will be set appropriately.


2.3.5 nx_connectinstance() (and nx_connect() macro)
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

#ifdef CONFIG_NX_MULTIUSER
NXHANDLE nx_connectinstance(FAR const char *svrmqname);
#define nx_connect(cb) nx_connectinstance(NX_DEFAULT_SERVER_MQNAME)
#endif


  Description:
  Open a connection from a client to the NX server.  One one client
  connection is normally needed per thread as each connection can host
  multiple windows.


  NOTES:


  
    This function returns before the connection is fully instantiated.
    it is necessary to wait for the connection event before using the
    returned handle.
  
  
    Multiple instances of the NX server may run at the same time,
    each with different message queue names.
  
  
    nx_connect() is simply a macro that can be used when only one
    server instance is required.  In that case, a default server name
    is used.
  


  Multiple user mode only!


  Input Parameters:
  

    svrmqname
    
The name for the server incoming message queue
  


  Returned Value:


    Success: A non-NULL handle used with subsequent NX accesses

    Failure:  NULL is returned and errno is set appropriately.


2.3.6 nx_open()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

#ifndef CONFIG_NX_MULTIUSER
NXHANDLE nx_open(FAR struct fb_vtable_s *fb);
#endif


  Description:
    Create, initialize and return an NX handle for use in subsequent
    NX API calls.  nx_open() is the single user equivalent of
    nx_connect() plus
    nx_run().


    Single user mode only!


  Input Parameters:
  

    fb
    
Vtable "object" of the framebuffer "driver" to use
    
cb
    
Callbacks used to process received NX server messages
  


  Returned Value:


    Success: A non-NULL handle used with subsequent NX accesses

    Failure:  NULL is returned and errno is set appropriately.


2.3.7 nx_disconnect()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

#ifdef CONFIG_NX_MULTIUSER
void nx_disconnect(NXHANDLE handle);
#endif


  Description:
  Disconnect a client from the NX server and/or free resources reserved
  by nx_connect()/nx_connectinstance().
  nx_disconnect() is muliti-user equivalent of
  nx_close().


  Multiple user mode only!


  Input Parameters:
  

    handle
    
The handle returned by nx_connect().
  


  Returned Value: None.


2.3.8 nx_close()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

#ifndef CONFIG_NX_MULTIUSER
void nx_close(NXHANDLE handle);
#endif


  Description:
  Close the single user NX interface.  nx_close is single-user equivalent
  of nx_disconnect().


  Single user mode only!


  Input Parameters:
  

    handle
    
The handle returned by nx_open().
  


  Returned Value: None


2.3.9 nx_eventhandler()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

#ifdef CONFIG_NX_MULTIUSER
int nx_eventhandler(NXHANDLE handle);
#else
#  define nx_eventhandler(handle) (OK)
#endif


  Description:
  The client code must call this function periodically to process
  incoming messages from the server.  If CONFIG_NX_BLOCKING is defined,
  then this function not return until a server message is received.


  When CONFIG_NX_BLOCKING is not defined, the client must exercise
  caution in the looping to assure that it does not eat up all of
  the CPU bandwidth calling nx_eventhandler repeatedly.
  nx_eventnotify()
  may be called to get a signal event whenever a new incoming server
  event is avaiable.


  Input Parameters:
  

    handle
    
The handle returned by nx_connect().
  


  Returned Value:


  
    OK: No errors occurred.  If CONFIG_NX_BLOCKING is defined,
    then one or more server messages were processed.
  
  
    ERROR: An error occurred and errno has been set appropriately.
    Of particular interest, it will return errno == EHOSTDOWN when the
    server is disconnected.  After that event, the handle can no longer be used.
  


2.3.10 nx_eventnotify()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

#if defined(CONFIG_NX_MULTIUSER) && !defined(CONFIG_DISABLE_SIGNALS)
int nx_eventnotify(NXHANDLE handle, int signo);
#else
#  define nx_eventnotify(handle, signo) (OK)
#endif


  Description:
  Rather than calling nx_eventhandler() periodically,
  the client may register to receive a signal when a server event is available.
  The client can then call nv_eventhandler() only when
  incoming events are available.


  The underlying implementation used mq_notifiy() and, as a result,
  the client must observe the rules for using mq_notifiy():
  

    
      Only one event is signaled.  Upon receipt of the signal, if the client
      wishes further notifications, it must call nx_eventnotify() again.
    
    
      The signal will only be issued when the message queue transitions from empty to
      not empty.
    
  


  Input Parameters:
  

    handle
    
The handle returned by nx_connect().
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.3.11 nx_openwindow()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

NXWINDOW nx_openwindow(NXHANDLE handle,
                       FAR const struct nx_callback_s *cb,
                       FAR void *arg);


  Description: Create a new window.


  Input Parameters:
  

    handle
    
The handle returned by nx_connect()
       or nx_open().
    
cb
    
Callbacks used to process window events
    
arg
    
User provided value that will be returned with NX callbacks.
  


  Returned Value:


    Success: A non-NULL handle used with subsequent NX accesses

    Failure:  NULL is returned and errno is set appropriately.


2.3.12 nx_closewindow()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

int nx_closewindow(NXWINDOW hwnd);


  Description:
  Destroy a window created by nx_openwindow() window.


  Input Parameters:
  

    hwnd
    
The handle returned by nx_openwindow()
       that identifies the window to be  destroyed.
       This handle must not have been one returned by
       nx_requestbkgd().
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.3.13 nx_requestbkgd()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

int nx_requestbkgd(NXHANDLE handle,
                   FAR const struct nx_callback_s *cb,
                   FAR void *arg);


  Description:
  NX normally controls a separate window called the background window.
  It repaints the window as necessary using only a solid color fill.  The
  background window always represents the entire screen and is always
  below other windows.  It is useful for an application to control the
  background window in the following conditions:


  
    If you want to implement a windowless solution.  The single screen
    can be used to creat a truly simple graphic environment.  In this
    case, you should probably also de-select CONFIG_NX_MULTIUSER as well.
  
  
    When you want more on the background than a solid color.  For
    example, if you want an image in the background, or animations in the
    background, or live video, etc.
  


  This API only requests the handle of the background window.  That
  handle will be returned asynchronously in a subsequent position and
  redraw callbacks.


  Cautions:


  
    The following should never be called using the background window.
    They are guaranteed to cause severe crashes:
    nx_setposition(),
    nx_setsize(),
    nx_raise(), or
    nx_lower().
  
  
    Neither nx_requestbkgd() nor
    nx_releasebkgd () should be called more than once.
    Multiple instances of the background window are not supported.
  



  Input Parameters:
  

    handle
    
The handle returned by nx_connect()
       or nx_open().
    
cb
    
Callbacks to use for processing background window events
    
arg
    
User provided argument (see nx_openwindow())
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.3.14 nx_releasebkgd()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

int nx_releasebkgd(NXWINDOW hwnd);


  Description:
  Release the background window previously acquired using
  nx_requestbkgd()
  and return control of the background to NX.


  Input Parameters:
  

    handle
    
The handle returned indirectly by
      nx_requestbkgd().
      This handle must not have been one created by
      nx_openwindow().
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.3.15 nx_getposition()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

int nx_getposition(NXWINDOW hwnd);


  Description:
   Request the position and size information for the selected window.  The
   values will be return asynchronously through the client callback function
   pointer.


  Input Parameters:
  

    hwnd
    
The handle returned by nx_openwindow() or
      nx_requestbkgd().
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.3.16 nx_setposition()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

int nx_setposition(NXWINDOW hwnd, FAR struct nxgl_point_s *pos);


  Description:
  Set the position and size for the selected window.


  Input Parameters:
  

    hwnd
    
The handle returned by nx_openwindow().
      This handle must not have been created by 
      nx_requestbkgd().
    
pos
    
The new position of the window
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.3.17 nx_setsize()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

int nx_setsize(NXWINDOW hwnd, FAR struct nxgl_size_s *size);


  Description: Set the size of the selected window.


  Input Parameters:
  

    hwnd
    
The handle returned by nx_openwindow().
      This handle must not have been created by 
      nx_requestbkgd().
    
size
    
The new size of the window (in pixels).
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.3.18 nx_raise()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

int nx_raise(NXWINDOW hwnd);


  Description: Bring the specified window to the top of the display.


  Input Parameters:
  

    hwnd
    
The handle returned by nx_openwindow().
      This handle must not have been created by 
      nx_requestbkgd().
    

    

  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.3.19 nx_lower()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

int nx_lower(NXWINDOW hwnd);


  Description: Lower the specified window to the bottom of the display.


  Input Parameters:
  

    hwnd
    
The handle returned by nx_openwindow().
      This handle must not have been created by 
      nx_requestbkgd().
    

    

  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.3.20 nx_fill()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

int nx_fill(NXWINDOW hwnd, FAR const struct nxgl_rect_s *rect,
                   nxgl_mxpixel_t color[CONFIG_NX_NPLANES]);


  Description:
   Fill the specified rectangle in the window with the specified color.


  Input Parameters:
  

    hwnd
    
The handle returned by nx_openwindow()
      or nx_requestbkgd()
    
rect
    
The location to be filled
    
color
    
The color to use in the fill
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.3.21 nx_filltrapezoid()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

int nx_filltrapezoid(NXWINDOW hwnd, FAR const struct nxgl_rect_s *clip,
                            FAR const struct nxgl_trapezoid_s *trap,
                            nxgl_mxpixel_t color[CONFIG_NX_NPLANES]);


  Description:
  Fill the specified trapezoidal region in the window with the specified color.


  Input Parameters:
  

    hwnd
    
The handle returned by nx_openwindow()
      or nx_requestbkgd()
    
clip
    
Clipping rectangle relative to window (may be null)
    
trap
    
The trapezoidal region to be filled
    
color
    
The color to use in the fill
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.3.22 nx_setbgcolor()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

int nx_setbgcolor(NXHANDLE handle,
                  nxgl_mxpixel_t color[CONFIG_NX_NPLANES]);


  Description: Set the color of the background.


  Input Parameters:
  

    handle
    
The handle created by nx_openwindow()
      or nx_requestbkgd()
    
color
    
The color to use in the background
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.3.23 nx_move()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

int nx_move(NXWINDOW hwnd, FAR const struct nxgl_rect_s *rect,
                   FAR const struct nxgl_point_s *offset);


  Description: Move a rectangular region within the window.


  Input Parameters:
  

    hwnd
    
The handle returned by nx_openwindow()
      or nx_requestbkgd() that specifies
      the window within which the move is to be done
    
rect
    
Describes the (source) rectangular region to move
    
offset
    
The offset to move the region
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.3.24 nx_bitmap()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

int nx_bitmap(NXWINDOW hwnd, FAR const struct nxgl_rect_s *dest,
                     FAR const void *src[CONFIG_NX_NPLANES],
                     FAR const struct nxgl_point_s *origin,
                     unsigned int stride);


  Description:
  Copy a rectangular region of a larger image into the rectangle in the
  specified window.


  Input Parameters:
  

    hwnd
    
The handle returned by nx_openwindow()
      or nx_requestbkgd() that specifies the
      window that will receive the bitmap image.
    
dest
    
 Describes the rectangular on the display that will receive the the bit map.
    
src
    
The start of the source image.  This is an array source images of size
      CONFIG_NX_NPLANES (probably 1).
    
origin
    
The origin of the upper, left-most corner of the full bitmap.
     Both dest and origin are in window coordinates, however, the origin
     may lie outside of the display.
    
stride
    
The width of the full source image in bytes.
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.3.25 nx_kbdin()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

#ifdef CONFIG_NX_KBD
int nx_kbdchin(NXHANDLE handle, ubyte ch);
int nx_kbdin(NXHANDLE handle, ubyte nch, FAR const ubyte *ch);
#endif


  Description:
  Used by a thread or interrupt handler that manages some kind of keypad
  hardware to report text information to the NX server.  That text
  data will be routed by the NX server to the appropriate window client.


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.3.26 nx_mousein()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>

#ifdef CONFIG_NX_MOUSE
int nx_mousein(NXHANDLE handle, nxgl_coord_t x, nxgl_coord_t y, ubyte buttons);
#endif


  Description:
  Used by a thread or interrupt handler that manages some kind of pointing
  hardware to report new positional data to the NX server.  That positional
  data will be routed by the NX server to the appropriate window client.


  Input Parameters:
  

    
    

  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4 NX Tool Kit (NXTK)

2.4.1 NXTK Types()


  This is the handle that can be used to access the window data region.

typedef FAR void *NXTKWINDOW;


2.4.2 nxtk_openwindow()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

NXTKWINDOW nxtk_openwindow(NXHANDLE handle,
                           FAR const struct nx_callback_s *cb,
                           FAR void *arg);


  Description: Create a new, framed window.


  Input Parameters:
  

    handle
    
The handle returned by nx_connect()
       or nx_open().
    
cb
    
Callbacks used to process window events
    
arg
    
User provided argument (see nx_openwindow())
  


  Returned Value:


    Success: A non-NULL handle used with subsequent NXTK window accesses

    Failure:  NULL is returned and errno is set appropriately.


2.4.3 nxtk_closewindow()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_closewindow(NXTKWINDOW hfwnd);


  Description:
  Close the window opened by nxtk_openwindow().


  Input Parameters:
  

    hfwnd
    
A handle previously returned by
      nxtk_openwindow().
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4.4 nxtk_getposition()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_getposition(NXTKWINDOW hfwnd);


  Description:
  Request the position and size information for the selected framed window.
  The size/position for the client window and toolbar will be return
  asynchronously through the client callback function pointer.


  Input Parameters:
  

    hfwnd
    
A handle previously returned by
      nxtk_openwindow().
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4.5 nxtk_setposition()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_setposition(NXTKWINDOW hfwnd, FAR struct nxgl_point_s *pos);


  Description:
  Set the position for the selected client window.  This position does not
  include the offsets for the borders nor for any toolbar.  Those offsets
  will be added in to set the full window position.


  Input Parameters:
  

    hfwnd
    
A handle previously returned by
      nxtk_openwindow().
    
pos
    
The new position of the client sub-window
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4.6 nxtk_setsize()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_setsize(NXTKWINDOW hfwnd, FAR struct nxgl_size_s *size);


  Description:
  Set the size for the selected client window.  This size does not
  include the sizes of the borders nor for any toolbar.  Those sizes
  will be added in to set the full window size.


  Input Parameters:
  

    hfwnd
    
A handle previously returned by
      nxtk_openwindow().
    
size
    
The new size of the client sub-window.
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4.7 nxtk_raise()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_raise(NXTKWINDOW hfwnd);


  Description:
  Bring the window containing the specified client sub-window to the top
  of the display.


  Input Parameters:
  

    hfwnd
    
A handle previously returned by
      nxtk_openwindow()
      specifying the window to be raised.
    

    

  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4.8 nxtk_lower()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_lower(NXTKWINDOW hfwnd);


  Description:
  Lower the window containing the specified client sub-window to the
  bottom of the display.


  Input Parameters:
  

     hfwnd
    
A handle previously returned by
      nxtk_openwindow()
      specifying the window to be lowered.
   

    

  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4.9 nxtk_fillwindow()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_fillwindow(NXTKWINDOW hfwnd, FAR const struct nxgl_rect_s *rect,
                    nxgl_mxpixel_t color[CONFIG_NX_NPLANES]);


  Description:
  Fill the specified rectangle in the client window with the specified color.


  Input Parameters:
  

    hfwnd
    
A handle previously returned by
      nxtk_openwindow().
    
rect
    
The location within the client window to be filled
    
color
    
The color to use in the fill
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4.10 nxtk_filltrapwindow()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_filltrapwindow(NXTKWINDOW hfwnd,
                        FAR const struct nxgl_trapezoid_s *trap,
                        nxgl_mxpixel_t color[CONFIG_NX_NPLANES]);


  Description:
  Fill the specified trapezoid in the client window with the specified color


  Input Parameters:
  

    hfwnd
    
A handle previously returned by
      nxtk_openwindow().
    
trap
    
The trapezoidal region to be filled.
    
color
    
The color to use in the fill.
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4.11 nxtk_movewindow()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_movewindow(NXTKWINDOW hfwnd, FAR const struct nxgl_rect_s *rect,
                    FAR const struct nxgl_point_s *offset);


  Description:
  Move a rectangular region within the client sub-window of a framed window.


  Input Parameters:
  

    hfwnd
    
A handle previously returned by
      nxtk_openwindow()
      specifying the client sub-window within which the move is to be done.
    
rect
    
Describes the rectangular region relative to the client sub-window to move.
    
offset
    
The offset to move the region
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4.12 nxtk_bitmapwindow()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_bitmapwindow(NXTKWINDOW hfwnd,
                      FAR const struct nxgl_rect_s *dest,
                      FAR const void *src[CONFIG_NX_NPLANES],
                      FAR const struct nxgl_point_s *origin,
                      unsigned int stride);


  Description:
  Copy a rectangular region of a larger image into the rectangle in the
  specified client sub-window.


  Input Parameters:
  

    hfwnd
    
A handle previously returned by
      nxtk_openwindow()
      specifying the client sub-window that will receive the bitmap.
    
dest
    
Describes the rectangular region on in the client sub-window
      will receive the bit map.
    
src
    
The start of the source image(s). This is an array source
      images of size CONFIG_NX_NPLANES (probably 1).
    
origin
    
The origin of the upper, left-most corner of the full bitmap.
      Both dest and origin are in sub-window coordinates, however, the
      origin may lie outside of the sub-window display.
    
stride
    
The width of the full source image in pixels.
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4.13 nxtk_opentoolbar()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_opentoolbar(NXTKWINDOW hfwnd, nxgl_coord_t height,
                     FAR const struct nx_callback_s *cb,
                     FAR void *arg);


  Description:
  Create a tool bar at the top of the specified framed window.


  Input Parameters:
  

    hfwnd
    
A handle previously returned by
      nxtk_openwindow().
    
height
    
The requested height of the toolbar in pixels.
    

    
Callbacks used to process toolbar events.
    

    
User provided value that will be returned with toolbar callbacks.
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4.14 nxtk_closetoolbar()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_closetoolbar(NXTKWINDOW hfwnd);


  Description:
  Remove the tool bar at the top of the specified framed window.


  Input Parameters:
  

    hfwnd
    
A handle previously returned by
      nxtk_openwindow().
    

    

  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4.15 nxtk_filltoolbar()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_filltoolbar(NXTKWINDOW hfwnd, FAR const struct nxgl_rect_s *rect,
                     nxgl_mxpixel_t color[CONFIG_NX_NPLANES]);


  Description:
  Fill the specified rectangle in the toolbar sub-window with the specified color.


  Input Parameters:
  

    hfwnd
    
A handle previously returned by
      nxtk_openwindow().
    
rect
    
The location within the toolbar window to be filled.
    
color
    
The color to use in the fill.
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4.16 nxtk_filltraptoolbar()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_filltraptoolbar(NXTKWINDOW hfwnd, FAR const struct nxgl_trapezoid_s *trap,
                         nxgl_mxpixel_t color[CONFIG_NX_NPLANES]);


  Description:
  Fill the specified trapezoid in the toolbar sub-window with the specified color.


  Input Parameters:
  

    hfwnd
    
A handle previously returned by
      nxtk_openwindow().
    
trap
    
The trapezoidal region to be filled
    
color
    
The color to use in the fill
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4.17 nxtk_movetoolbar()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_movetoolbar(NXTKWINDOW hfwnd, FAR const struct nxgl_rect_s *rect,
                     FAR const struct nxgl_point_s *offset);


  Description:
   Move a rectangular region within the toolbar sub-window of a framed window.


  Input Parameters:
  

    hfwnd
    
A handle identifying sub-window containing the toolbar within which the move is
      to be done.
      This handle must have previously been returned by
      nxtk_openwindow().
    
rect
    
Describes the rectangular region relative to the toolbar sub-window to move.
    
offset
    
The offset to move the region
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.4.18 nxtk_bitmaptoolbar()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nx.h>
#include <nuttx/nxtk.h>

int nxtk_bitmaptoolbar(NXTKWINDOW hfwnd,
                       FAR const struct nxgl_rect_s *dest,
                       FAR const void *src[CONFIG_NX_NPLANES],
                       FAR const struct nxgl_point_s *origin,
                       unsigned int stride);


  Description:
  Copy a rectangular region of a larger image into the rectangle in the
  specified toolbar sub-window.


  Input Parameters:
  

    hfwnd
    
A handle previously returned by
      nxtk_openwindow().
    
dest
    
Describes the rectangular region on in the toolbar sub-window
           will receive the bit map.
    
src
    
The start of the source image.
    
origin
    
The origin of the upper, left-most corner of the full bitmap.
           Both dest and origin are in sub-window coordinates, however, the
           origin may lie outside of the sub-window display.
    
stride
    
The width of the full source image in bytes.
  


  Returned Value:
  OK on success;
  ERROR on failure with errno set appropriately


2.5 NX Fonts Support (NXFONTS)

2.5.1 NXFONTS Types()

  This structures provides the metrics for one glyph:

struct nx_fontmetic_s
{
  uint32 stride   : 2;      /* Width of one font row in bytes */
  uint32 width    : 6;      /* Width of the font in bits */
  uint32 height   : 6;      /* Height of the font in rows */
  uint32 xoffset  : 6;      /* Top, left-hand corner X-offset in pixels */
  uint32 yoffset  : 6;      /* Top, left-hand corner y-offset in pixels */
  uint32 unused   : 6;
};



  This structure binds the glyph metrics to the glyph bitmap:

struct nx_fontbitmap_s
{
  struct nx_fontmetic_s metric; /* Character metrics */
  FAR const ubyte *bitmap;      /* Pointer to the character bitmap */
};



  This structure describes one contiguous grouping of glyphs that
  can be described by an array starting with encoding first and
  extending through (first + nchars - 1).

struct nx_fontset_s
{
  ubyte  first;             /* First bitmap character code */
  ubyte  nchars;            /* Number of bitmap character codes */
  FAR const struct nx_fontbitmap_s *bitmap;
};



  This structure describes the overall fontset:

struct nx_font_s
{
  ubyte  mxheight;          /* Max height of one glyph in rows */
  ubyte  mxwidth;           /* Max width of any glyph in pixels */
  ubyte  mxbits;            /* Max number of bits per character code */
  ubyte  spwidth;           /* The width of a space in pixels */
};


2.5.2 nxf_getfontset()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nxfonts.h>

FAR const struct nx_font_s *nxf_getfontset(void);


  Description:
  Return information about the current font set.


  Input Parameters: None


  Returned Value:
  An instance of struct nx_font_s describing the font set.


2.5.3 nxf_getbitmap()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nxfonts.h>

FAR const struct nx_fontbitmap_s *nxf_getbitmap(uint16 ch);


  Description:
  Return font bitmap information for the selected character encoding.


  Input Parameters:
  

    
    

  


  Returned Value:
  An instance of struct nx_fontbitmap_s describing the glyph.


2.5.4 nxf_convert_*bpp()
Function Prototype:
#include <nuttx/nxglib.h>
#include <nuttx/nxfonts.h>

int nxf_convert_2bpp(FAR ubyte *dest, uint16 height,
                     uint16 width, uint16 stride, uint16 ch,
                     nxgl_mxpixel_t color);
int nxf_convert_4bpp(FAR ubyte *dest, uint16 height,
                     uint16 width, uint16 stride, uint16 ch,
                     nxgl_mxpixel_t color);
int nxf_convert_8bpp(FAR ubyte *dest, uint16 height,
                     uint16 width, uint16 stride, uint16 ch,
                     nxgl_mxpixel_t color);
int nxf_convert_16bpp(FAR uint16 *dest, uint16 height,
                      uint16 width, uint16 stride, uint16 ch,
                      nxgl_mxpixel_t color);
int nxf_convert_24bpp(FAR uint32 *dest, uint16 height,
                      uint16 width, uint16 stride, uint16 ch,
                      nxgl_mxpixel_t color);
int nxf_convert_32bpp(FAR uint32 *dest, uint16 height,
                      uint16 width, uint16 stride, uint16 ch,
                      nxgl_mxpixel_t color);


  Description: Convert the 1BPP font to a new pixel depth.


  Input Parameters:
  

    dest
    
The destination buffer provided by the caller.
    
height
    
The max height of the returned char in rows.
    
width
    
The max width of the returned char in pixels.
    
stride
    
The width of the destination buffer in bytes.
    
ch
    
The character code to convert.
    
color
    
The color to use for '1' bits in the font bitmap (0 bits are transparent).
  


  Returned Value:
  On Success, these functions returns the actual width of the font in bytes.
  on failed, a negated errno is retured.



  
    
      Appendix A graphics/ Directory Structure
    
  



  
    graphics/nxglib
      
The NuttX tiny graphics library.
      The directory contains generic utilities support operations on primitive graphics objects
      and logic to rasterize directly into a framebuffer.
      It has no concept of windows (other than the one, framebuffer  window).

    
graphics/nxbe
      
This is the back-end of a tiny windowing system.
      It can be used with either of two front-ends to complete a windowing system (see
      nxmu and nxsu/ below).
      It contains most of the important window management logic:  clipping, window controls,
      window drawing, etc.

    
graphics/nxsu
      
This is the NX single user front end.
      When combined with the generic back-end (nxbe), it implements a
      single threaded, single user windowing system.
      The files in this directory present the window APIs described in
      include/nuttx/nx.h.
      The single user front-end is selected when CONFIG_NX_MULTIUSER is not
      defined in the NuttX configuration file.

    
graphics/nxsu
      
This is the NX multi user front end.
      When combined with the generic back-end (nxbe), it implements a
      multi-threaded, multi-user windowing system.
      The files in this directory present the window APIs described in
      include/nuttx/nx.h.
      The multi-user front end includes a graphics server that executes on its own thread;
      multiple graphics clients then communicate with the server via a POSIX message
      queue to serialize window operations from many threads.
      The multi-user front-end is selected when CONFIG_NX_MULTIUSER is defined
      in the NuttX configuration file.

    
graphics/nxfonts
      
This is where the NXFONTS implementation resides.
      This is a relatively low-level set of charset set/glyph management APIs.
      See include/nuttx/nxfonts.h.

    
graphics/nxtk
      
This is where the NXTOOLKIT implementation resides.
      This toolkit is built on top of NX and works with either the single-user or
      multi-user NX version.
      See include/nuttx/nxtk.h.

    
graphics/nxwidgets
      
At one time, I planned to put NXWIDGETS implementation here, but not anymore.
  




  
    
      Appendix B NX Configuration Options
    
  


B.1 General Configuration Settings


  
    CONFIG_NX
    Enables overall support for graphics library and NX
  


B.2 NXGL Configuration Settings


  
    CONFIG_NX_NPLANES:
      
Some YUV color formats requires support for multiple planes,
      one for each color component.  Unless you have such special
      hardware, this value should be undefined or set to 1.
    
CONFIG_NX_DISABLE_1BPP, CONFIG_NX_DISABLE_2BPP,
    CONFIG_NX_DISABLE_4BPP, CONFIG_NX_DISABLE_8BPP
    CONFIG_NX_DISABLE_16BPP, CONFIG_NX_DISABLE_24BPP, and
    CONFIG_NX_DISABLE_32BPP:
      
NX supports a variety of pixel depths.  You can save some
      memory by disabling support for unused color depths.
    
CONFIG_NX_PACKEDMSFIRST:
      
If a pixel depth of less than 8-bits is used, then NX needs
      to know if the pixels pack from the MS to LS or from LS to MS
  


B.3 NX Configuration Settings


  
    CONFIG_NX_MOUSE:
      
Build in support for mouse input.
    
CONFIG_NX_KBD:
      
Build in support of keypad/keyboard input.
  


B.4 NX Multi-User (Only) Configuration Settings


  
    CONFIG_NX_MULTIUSER:
      
Configures NX in multi-user mode.
    
CONFIG_NX_BLOCKING
      
Open the client message queues in blocking mode.  In this case,
    
nx_eventhandler()  will not return until a message is received and processed.
    
CONFIG_NX_MXSERVERMSGS and CONFIG_NX_MXCLIENTMSGS
      
Specifies the maximum number of messages that can fit in
      the message queues.  No additional resources are allocated, but
      this can be set to prevent flooding of the client or server with
      too many messages (CONFIG_PREALLOC_MQ_MSGS controls how many
      messages are pre-allocated).
  


B.5 NXTK Configuration Settings


  
    CONFIG_NXTK_BORDERWIDTH:
      
Specifies with with of the border (in pixels) used with
      framed windows.   The default is 4.
    
CONFIG_NXTK_BORDERCOLOR1 and CONFIG_NXTK_BORDERCOLOR2:
      
Specify the colors of the border used with framed windows.
    
CONFIG_NXTK_BORDERCOLOR2 is the shadow side color and so
      
is normally darker.  The default is medium and dark grey,
      respectively
    
CONFIG_NXTK_AUTORAISE:
      
If set, a window will be raised to the top if the mouse position
      is over a visible portion of the window.  Default: A mouse
      button must be clicked over a visible portion of the window.
  


B.6 NXFONTS Configuration Settings


  
    CONFIG_NXFONTS_CHARBITS:
      
The number of bits in the character set.  Current options are
      only 7 and 8.  The default is 7.
    
CONFIG_NXFONT_SANS:
      
At present, there is only one font.  But if there were were more,
      then this option would select the sans serif font.
  



  
    
      Appendix C NX Test Coverage
    
  



  The primary test tool for debugging NX resides at examples/nx.
  At present, that test only exercises a subset of NX; the remainder is essentially
  untested.
  The following table describes the testing performed on each NX API:


Table C.1: NX Test Coverage


  To be provided

NX Graphics Subsystem

Table of Contents

1.0 Introduction

1.1 Overview

1.2 Objectives

1.3 Organization

1.3.1 NX Graphics Library (NXGL)

1.3.2 NX (NXSU and NXMU)

1.3.3 NX Tool Kit (NXTK)

1.3.4 NX Fonts Support (NXFONTS)

1.3.5 NX Widgets (NXWIDGETS)

2.0 NX User APIs

2.1 NX Header Files

2.2 NX Graphics Library (NXGL)

2.2.1 NXGL Types

2.2.1 nxgl_rgb2yuv()

2.2.2 nxgl_yuv2rgb()

2.2.3 nxgl_rectcopy()

2.2.4 nxgl_rectoffset()

2.2.5 nxgl_vectoradd()

2.2.6 nxgl_vectorsubtract()

2.2.7 nxgl_rectintersect()

2.2.8 nxgl_rectunion()

2.2.9 nxgl_nonintersecting()

2.2.10 nxgl_rectoverlap()

2.2.11 nxgl_rectinside()

2.2.12 nxgl_rectsize()

2.2.13 nxgl_nullrect()

2.2.14 nxgl_runoffset()

2.2.15 nxgl_runcopy()

2.2.16 nxgl_trapoffset()

2.2.1 nxgl_trapcopy()

2.2.1 nxgl_colorcopy

2.3 NX

2.3.1 Pre-Processor Definitions

2.3.2 NX Types

2.3.3 NX Server Callbacks

2.3.3.1 redraw()

2.3.3.2 position()

2.3.3.3 mousein()

2.3.3.4 kbdin()

2.3.4 nx_runinstance() (and nx_run() macro)

2.3.5 nx_connectinstance() (and nx_connect() macro)

2.3.6 nx_open()

2.3.7 nx_disconnect()

2.3.8 nx_close()

2.3.9 nx_eventhandler()

2.3.10 nx_eventnotify()

2.3.11 nx_openwindow()

2.3.12 nx_closewindow()

2.3.13 nx_requestbkgd()

2.3.14 nx_releasebkgd()

2.3.15 nx_getposition()

2.3.16 nx_setposition()

2.3.17 nx_setsize()

2.3.18 nx_raise()

2.3.19 nx_lower()

2.3.20 nx_fill()

2.3.21 nx_filltrapezoid()

2.3.22 nx_setbgcolor()

2.3.23 nx_move()

2.3.24 nx_bitmap()

2.3.25 nx_kbdin()

2.3.26 nx_mousein()

2.4 NX Tool Kit (NXTK)

2.4.1 NXTK Types()

2.4.2 nxtk_openwindow()

2.4.3 nxtk_closewindow()

2.4.4 nxtk_getposition()

2.4.5 nxtk_setposition()

2.4.6 nxtk_setsize()

2.4.7 nxtk_raise()

2.4.8 nxtk_lower()

2.4.9 nxtk_fillwindow()

2.4.10 nxtk_filltrapwindow()

2.4.11 nxtk_movewindow()

2.4.12 nxtk_bitmapwindow()

2.4.13 nxtk_opentoolbar()

2.4.14 nxtk_closetoolbar()

2.4.15 nxtk_filltoolbar()

1.3.1 NX Graphics Library (`NXGL`)

1.3.2 NX (`NXSU` and `NXMU`)

1.3.3 NX Tool Kit (`NXTK`)

1.3.4 NX Fonts Support (`NXFONTS`)

1.3.5 NX Widgets (`NXWIDGETS`)

2.2 NX Graphics Library (`NXGL`)

2.2.1 `nxgl_rgb2yuv()`

2.2.2 `nxgl_yuv2rgb()`

2.2.3 `nxgl_rectcopy()`

2.2.4 `nxgl_rectoffset()`

2.2.5 `nxgl_vectoradd()`

2.2.6 `nxgl_vectorsubtract()`

2.2.7 `nxgl_rectintersect()`

2.2.8 `nxgl_rectunion()`

2.2.9 `nxgl_nonintersecting()`

2.2.10 `nxgl_rectoverlap()`

2.2.11 `nxgl_rectinside()`

2.2.12 `nxgl_rectsize()`

2.2.13 `nxgl_nullrect()`

2.2.14 `nxgl_runoffset()`

2.2.15 `nxgl_runcopy()`

2.2.16 `nxgl_trapoffset()`

2.2.1 `nxgl_trapcopy()`

2.2.1 `nxgl_colorcopy`

2.3.3.1 `redraw()`

2.3.3.2 `position()`

2.3.3.3 `mousein()`

2.3.3.4 `kbdin()`

2.3.4 `nx_runinstance()` (and `nx_run() macro)`

2.3.5 `nx_connectinstance()` (and `nx_connect()` macro)

2.3.6 `nx_open()`

2.3.7 `nx_disconnect()`

2.3.8 `nx_close()`

2.3.9 `nx_eventhandler()`

2.3.10 `nx_eventnotify()`

2.3.11 `nx_openwindow()`

2.3.12 `nx_closewindow()`

2.3.13 `nx_requestbkgd()`

2.3.14 `nx_releasebkgd()`

2.3.15 `nx_getposition()`

2.3.16 `nx_setposition()`

2.3.17 `nx_setsize()`

2.3.18 `nx_raise()`

2.3.19 `nx_lower()`

2.3.20 `nx_fill()`

2.3.21 `nx_filltrapezoid()`

2.3.22 `nx_setbgcolor()`

2.3.23 `nx_move()`

2.3.24 `nx_bitmap()`

2.3.25 `nx_kbdin()`

2.3.26 `nx_mousein()`

2.4 NX Tool Kit (`NXTK`)

2.4.1 `NXTK Types()`

2.4.2 `nxtk_openwindow()`

2.4.3 `nxtk_closewindow()`

2.4.4 `nxtk_getposition()`

2.4.5 `nxtk_setposition()`

2.4.6 `nxtk_setsize()`

2.4.7 `nxtk_raise()`

2.4.8 `nxtk_lower()`

2.4.9 `nxtk_fillwindow()`

2.4.10 `nxtk_filltrapwindow()`

2.4.11 `nxtk_movewindow()`

2.4.12 `nxtk_bitmapwindow()`

2.4.13 `nxtk_opentoolbar()`

2.4.14 `nxtk_closetoolbar()`

2.4.15 `nxtk_filltoolbar()`

2.4.16 `nxtk_filltraptoolbar()`

2.4.17 `nxtk_movetoolbar()`

2.4.18 `nxtk_bitmaptoolbar()`

2.5 NX Fonts Support (`NXFONTS`)

2.5.1 `NXFONTS Types()`

2.5.2 `nxf_getfontset()`

2.5.3 `nxf_getbitmap()`

2.5.4 `nxf_convert_*bpp()`

Appendix A `graphics/` Directory Structure