--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/balloon_help.c	Mon Aug 13 09:30:11 2007 +0200
@@ -0,0 +1,613 @@
+/*
+ * Balloon Help
+ *
+ * Version: 1.337 (Sun Apr 13 04:52:10 1997)
+ *
+ * Written by Douglas Keller <dkeller@vnet.ibm.com>
+ *
+ *
+ */
+
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+#include <X11/extensions/shape.h>
+
+#include <X11/Intrinsic.h>
+
+#include "balloon_help.h"
+
+#define max(x,y) (x>y?x:y)
+
+#undef bool
+#define bool int
+
+#define MARGIN_WIDTH      4
+#define POINTER_OFFSET    8
+#define BORDER_WIDTH      2
+#define BORDER_WIDTH_HALF 1
+
+#define CONE_HEIGHT    20
+#define CONE_WIDTH     50
+
+#define SHAPE_CONE_TOP          (1<<0)
+#define SHAPE_CONE_LEFT         (1<<1)
+#define SHAPE_CONE_TOP_LEFT     (SHAPE_CONE_TOP | SHAPE_CONE_LEFT)
+#define SHAPE_CONE_TOP_RIGHT    (SHAPE_CONE_TOP)
+#define SHAPE_CONE_BOTTOM_LEFT  (SHAPE_CONE_LEFT)
+#define SHAPE_CONE_BOTTOM_RIGHT (0)
+#define SHAPE_CONE_FREE         (-1)
+
+
+static Display* b_dpy;
+
+static XFontStruct* b_fontStruct;
+static GC b_gc;
+
+static GC b_shineGC;
+static GC b_shadowGC;
+
+static Window b_win;
+static bool   b_winMapped;
+
+static Pixmap b_mask;
+static int    b_maskWidth, b_maskHeight;
+static GC     b_maskGC;
+
+static const char* b_text;
+static int b_width, b_height;
+
+static int b_lastX, b_lastY;
+
+static XtIntervalId b_timer;
+static unsigned long b_delay;
+
+static int b_screenWidth, b_screenHeight;
+
+static int b_lastShape;
+
+/*============================================================================
+
+============================================================================*/
+
+static GC create_gc( Display* dpy, Window win, unsigned long fg, unsigned long bg,
+                     XFontStruct* fontStruct )
+{
+  XGCValues gcv;
+  unsigned long mask;
+
+  gcv.foreground = fg;
+  gcv.background = bg;
+  gcv.font       = fontStruct->fid;
+  gcv.join_style = JoinMiter;
+  gcv.line_width = BORDER_WIDTH;
+
+  mask = GCFont | GCBackground | GCForeground | GCJoinStyle | GCLineWidth;
+
+  return XCreateGC( dpy, win, mask, &gcv );
+}
+
+static void destroy_gc( Display* dpy, GC gc )
+{
+  if( gc )
+  {
+    XFreeGC( dpy, gc );
+  }
+}
+
+/*============================================================================
+
+============================================================================*/
+
+static Window create_window( Display* dpy, unsigned long bg )
+{
+  Window win;
+  XSetWindowAttributes attr;
+  unsigned long attr_mask;
+
+  attr_mask              = CWOverrideRedirect | CWBackPixel | CWSaveUnder;
+  attr.override_redirect = True;
+  attr.background_pixel  = bg;
+  attr.save_under        = True;
+
+  win =
+    XCreateWindow( dpy,
+                   DefaultRootWindow( dpy ),
+                   0, 0, 1, 1,
+                   0,
+                   CopyFromParent, InputOutput, CopyFromParent,
+                   attr_mask, &attr );
+
+  XSelectInput( dpy, win,
+                SubstructureRedirectMask |
+                SubstructureNotifyMask |
+                ExposureMask |
+                EnterWindowMask |
+                LeaveWindowMask );
+  return win;
+}
+
+static void destroy_window( Display* dpy, Window win )
+{
+  if( win )
+  {
+    XDestroyWindow( dpy, win );
+  }
+}
+
+/*============================================================================
+
+============================================================================*/
+
+static void get_pointer_xy( Display* dpy, int* x_return, int* y_return )
+{
+  int dummy;
+  unsigned int mask;
+  Window dummy_win;
+
+  XQueryPointer( dpy, RootWindow(dpy, DefaultScreen(dpy)), &dummy_win, &dummy_win,
+                 x_return, y_return, &dummy, &dummy, &mask );
+}
+
+/*============================================================================
+
+============================================================================*/
+
+static void create_pixmap_mask( int width, int height )
+{
+  b_maskWidth  = width;
+  b_maskHeight = height;
+  b_mask = XCreatePixmap( b_dpy, b_win, width, height, 1 );
+}
+
+static void destroy_pixmap_mask( void )
+{
+  XFreePixmap( b_dpy, b_mask );
+}
+
+static void grow_pixmap_mask( int width, int height )
+{
+  if( width > b_maskWidth || height > b_maskHeight )
+  {
+    destroy_pixmap_mask();
+    create_pixmap_mask( width, height );
+  }
+}
+
+/*============================================================================
+
+============================================================================*/
+
+static void text_extent( XFontStruct* fontStruct, const char* text, int len,
+                         int* width, int* height )
+{
+  XCharStruct extent;
+  int dummy;
+
+  XTextExtents( fontStruct, text, len, &dummy, &dummy, &dummy, &extent );
+
+  *width  = extent.width;
+  *height = fontStruct->ascent + fontStruct->descent;
+}
+
+static void get_text_size( Display* dpy, XFontStruct* fontStruct, const char* text,
+                           int* max_width, int* max_height )
+{
+  int width;
+  int height;
+  const char* start;
+  const char* end;
+
+  *max_width = *max_height = 0;
+
+  start = text;
+  while( (end = strchr(start, '\n')) )
+  {
+    text_extent( fontStruct, start, end - start, &width, &height );
+    *max_width  = max( width, *max_width );
+    *max_height += height;
+
+    start = end + 1;
+  }
+  text_extent( fontStruct, start, strlen(start), &width, &height );
+  *max_width  = max( width, *max_width );
+  *max_height += height;
+
+  /* Min width */
+  *max_width  = max( *max_width, CONE_WIDTH / 2 * 3 );
+
+}
+
+static void draw_text( Display* dpy, Window win, GC gc, XFontStruct* fontStruct,
+                       int x, int y, const char* text )
+{
+  const char* start;
+  const char* end;
+  int font_height;
+
+  y += fontStruct->ascent;
+
+  font_height = fontStruct->ascent + fontStruct->descent;
+
+  start = text;
+  while( (end = strchr(start, '\n')) )
+  {
+    XDrawString( dpy, win, gc, x, y, start, end - start );
+
+    start = end + 1;
+    y += font_height;
+  }
+  XDrawString( dpy, win, gc, x, y, start, strlen(start) );
+}
+
+/*============================================================================
+
+============================================================================*/
+
+static int get_shape( int last_shape, int x, int y, int width, int height,
+                      int screen_width, int screen_height )
+{
+  /* Can we use last_shape */
+  if( SHAPE_CONE_TOP_LEFT == last_shape )
+  {
+    if( (x + width < screen_width) && (y + height < screen_height) )
+    {
+      return last_shape;
+    }
+  }
+  else if( SHAPE_CONE_TOP_RIGHT == last_shape )
+  {
+    if( (x - width > 0) && (y + height < screen_height) )
+    {
+      return last_shape;
+    }
+  }
+  else if( SHAPE_CONE_BOTTOM_LEFT == last_shape )
+  {
+    if( (x + width < screen_width) && (y - height > 0) )
+    {
+      return last_shape;
+    }
+  }
+  else if( SHAPE_CONE_BOTTOM_RIGHT == last_shape )
+  {
+    if( (x - width > 0) && (y - height > 0) )
+    {
+      return last_shape;
+    }
+  }
+
+  /* Try to pick a shape that will not get changed, ie if top left quadrant, top_left */
+  if( x < screen_width / 2 )
+  {
+    if( y < screen_height / 2 )
+    {
+      return SHAPE_CONE_TOP_LEFT;
+    }
+    else
+    {
+      return SHAPE_CONE_BOTTOM_LEFT;
+    }
+  }
+  else
+  {
+    if( y < screen_height / 2 )
+    {
+      return SHAPE_CONE_TOP_RIGHT;
+    }
+    else
+    {
+      return SHAPE_CONE_BOTTOM_RIGHT;
+    }
+  }
+
+  /* ### if width or height is greater than 1/2 the width or height then we might
+     run off the screen */
+
+  abort();
+
+  return 0;
+}
+
+static void make_mask( int shape, int x, int y, int width, int height )
+{
+  XPoint cone[ 3 ];
+
+  grow_pixmap_mask( width, height );
+
+  /* Clear mask */
+  XSetForeground( b_dpy, b_maskGC, 0 );
+  XFillRectangle( b_dpy, b_mask, b_maskGC,
+                  0, 0, width, height );
+
+  /* Enable text area */
+  XSetForeground( b_dpy, b_maskGC, 1 );
+  XFillRectangle( b_dpy, b_mask, b_maskGC,
+                  0, shape & SHAPE_CONE_TOP ? CONE_HEIGHT : 0, width, height - CONE_HEIGHT );
+
+  /* Enable for cone area */
+  cone[0].x = (shape & SHAPE_CONE_LEFT) ? CONE_WIDTH / 2 : width - (CONE_WIDTH / 2);
+  cone[0].y = (shape & SHAPE_CONE_TOP)  ? CONE_HEIGHT    : height - CONE_HEIGHT;
+  cone[1].x = (shape & SHAPE_CONE_LEFT) ? 0              : width;
+  cone[1].y = (shape & SHAPE_CONE_TOP)  ? 0              : height;
+  cone[2].x = (shape & SHAPE_CONE_LEFT) ? CONE_WIDTH     : width - CONE_WIDTH;
+  cone[2].y = (shape & SHAPE_CONE_TOP)  ? CONE_HEIGHT    : height - CONE_HEIGHT;
+
+  XFillPolygon( b_dpy, b_mask, b_maskGC, cone, 3, Nonconvex, CoordModeOrigin );
+
+}
+
+static void show_help( XtPointer data, XtIntervalId* id )
+{
+  int x, y;
+  int shape;
+  XPoint border[ 3 ];
+
+  if( id == NULL || (id && b_timer) && b_text )
+  {
+    b_timer = None;
+
+    /* size */
+    get_text_size( b_dpy, b_fontStruct, b_text, &b_width, &b_height );
+    b_width  += 2 * MARGIN_WIDTH + 2 * BORDER_WIDTH;
+    b_height += 2 * MARGIN_WIDTH + 2 * BORDER_WIDTH + CONE_HEIGHT;
+
+    /* origin */
+    get_pointer_xy( b_dpy, &x, &y );
+
+    /* guess at shape */
+    shape = get_shape( b_lastShape, x, y, b_width, b_height, b_screenWidth, b_screenHeight );
+
+    x += (shape & SHAPE_CONE_LEFT) ? POINTER_OFFSET : -POINTER_OFFSET;
+    y += (shape & SHAPE_CONE_TOP)  ? POINTER_OFFSET : -POINTER_OFFSET;
+
+    /* make sure it is still ok with offset */
+    shape = get_shape( shape, x, y, b_width, b_height, b_screenWidth, b_screenHeight );
+
+    b_lastX = x;
+    b_lastY = y;
+    b_lastShape = shape;
+
+
+    make_mask( shape, x, y, b_width, b_height );
+
+    XShapeCombineMask( b_dpy, b_win, ShapeBounding, 0, 0, b_mask, ShapeSet );
+
+    XMoveResizeWindow( b_dpy, b_win,
+                       (shape & SHAPE_CONE_LEFT) ? x : x - b_width,
+                       (shape & SHAPE_CONE_TOP)  ? y : y - b_height,
+                       b_width, b_height );
+
+    XClearWindow( b_dpy, b_win );
+
+    XMapRaised( b_dpy, b_win );
+    b_winMapped = True;
+
+    draw_text( b_dpy, b_win, b_gc, b_fontStruct,
+               BORDER_WIDTH + MARGIN_WIDTH,
+               BORDER_WIDTH + MARGIN_WIDTH + ((shape & SHAPE_CONE_TOP) ? CONE_HEIGHT : 0),
+               b_text );
+
+    /* 3d border */
+    /* shine- top left */
+    border[0].x = 0 + BORDER_WIDTH_HALF;
+    border[0].y = ((shape & SHAPE_CONE_TOP) ? b_height : b_height - CONE_HEIGHT) - BORDER_WIDTH_HALF;
+    border[1].x = 0 + BORDER_WIDTH_HALF;
+    border[1].y = ((shape & SHAPE_CONE_TOP) ? CONE_HEIGHT : 0) + BORDER_WIDTH_HALF;
+    border[2].x = b_width - BORDER_WIDTH_HALF;
+    border[2].y = border[1].y;
+    XDrawLines( b_dpy, b_win, b_shineGC, border, 3, CoordModeOrigin );
+
+    /* shadow- bottom right */
+    border[0].x = 0 + BORDER_WIDTH_HALF;
+    border[0].y = ((shape & SHAPE_CONE_TOP) ? b_height : b_height - CONE_HEIGHT) - BORDER_WIDTH_HALF;
+    border[1].x = b_width - BORDER_WIDTH_HALF;
+    border[1].y = border[0].y;
+    border[2].x = b_width - BORDER_WIDTH_HALF;
+    border[2].y = ((shape & SHAPE_CONE_TOP) ? CONE_HEIGHT : 0) + BORDER_WIDTH_HALF;
+    XDrawLines( b_dpy, b_win, b_shadowGC, border, 3, CoordModeOrigin );
+
+    /* cone */
+    if( SHAPE_CONE_TOP_LEFT == shape )
+    {
+      XClearArea( b_dpy, b_win,
+                  CONE_WIDTH / 2 + BORDER_WIDTH,
+                  CONE_HEIGHT,
+                  CONE_WIDTH / 2 - BORDER_WIDTH,
+                  BORDER_WIDTH, False );
+      XDrawLine( b_dpy, b_win, b_shadowGC,
+                 0,
+                 0,
+                 CONE_WIDTH / 2 + BORDER_WIDTH_HALF,
+                 CONE_HEIGHT );
+      XDrawLine( b_dpy, b_win, b_shineGC,
+                 0,
+                 0,
+                 CONE_WIDTH - BORDER_WIDTH_HALF,
+                 CONE_HEIGHT );
+    }
+    else if( SHAPE_CONE_TOP_RIGHT == shape )
+    {
+      XClearArea( b_dpy, b_win,
+                  b_width - CONE_WIDTH + BORDER_WIDTH,
+                  CONE_HEIGHT,
+                  CONE_WIDTH / 2 - BORDER_WIDTH,
+                  BORDER_WIDTH, False );
+      XDrawLine( b_dpy, b_win, b_shadowGC,
+                 b_width,
+                 0,
+                 b_width - CONE_WIDTH / 2 - BORDER_WIDTH_HALF,
+                 CONE_HEIGHT );
+      XDrawLine( b_dpy, b_win, b_shineGC,
+                 b_width,
+                 0,
+                 b_width - CONE_WIDTH + BORDER_WIDTH_HALF,
+                 CONE_HEIGHT );
+    }
+    else if( SHAPE_CONE_BOTTOM_LEFT == shape )
+    {
+      XClearArea( b_dpy, b_win,
+                  CONE_WIDTH / 2 + BORDER_WIDTH,
+                  b_height - CONE_HEIGHT - BORDER_WIDTH,
+                  CONE_WIDTH / 2 - BORDER_WIDTH,
+                  BORDER_WIDTH, False );
+      XDrawLine( b_dpy, b_win, b_shadowGC,
+                 0,
+                 b_height - 1,
+                 CONE_WIDTH,
+                 b_height - 1 - CONE_HEIGHT );
+      XDrawLine( b_dpy, b_win, b_shineGC,
+                 0,
+                 b_height - 1,
+                 CONE_WIDTH / 2 + BORDER_WIDTH,
+                 b_height - 1 - CONE_HEIGHT );
+    }
+    else if( SHAPE_CONE_BOTTOM_RIGHT == shape )
+    {
+      XClearArea( b_dpy, b_win,
+                  b_width - 1 - CONE_WIDTH + BORDER_WIDTH,
+                  b_height - CONE_HEIGHT - BORDER_WIDTH,
+                  CONE_WIDTH / 2 - BORDER_WIDTH - 1,
+                  BORDER_WIDTH, False );
+      XDrawLine( b_dpy, b_win, b_shadowGC,
+                 b_width - 1,
+                 b_height - 1,
+                 b_width - 1 - CONE_WIDTH,
+                 b_height - 1 - CONE_HEIGHT );
+      XDrawLine( b_dpy, b_win, b_shineGC,
+                 b_width - 1,
+                 b_height - 1,
+                 b_width - 1 - CONE_WIDTH / 2 - BORDER_WIDTH,
+                 b_height - 1 - CONE_HEIGHT);
+    }
+  }
+
+}
+
+/*============================================================================
+
+============================================================================*/
+
+void balloon_help_create( Display* dpy,
+                          Pixel fg, Pixel bg, Pixel shine, Pixel shadow,
+                          XFontStruct* font )
+{
+  if( b_dpy ) balloon_help_destroy();
+
+  b_dpy = dpy;
+
+  b_fontStruct = font;
+
+  b_win = create_window( dpy, bg );
+  b_gc  = create_gc( dpy, b_win, fg, bg, b_fontStruct );
+
+  b_shineGC  = create_gc( dpy, b_win, shine, bg, b_fontStruct );
+  b_shadowGC = create_gc( dpy, b_win, shadow, bg, b_fontStruct );
+
+  create_pixmap_mask( 1, 1 );
+  b_maskGC = create_gc( dpy, b_mask, bg, fg, b_fontStruct );
+
+  b_winMapped = False;
+  b_timer     = None;
+  b_delay     = 500;
+
+  b_screenWidth  = DisplayWidth( b_dpy, DefaultScreen(b_dpy) );
+  b_screenHeight = DisplayHeight( b_dpy, DefaultScreen(b_dpy) );
+
+  b_lastShape = SHAPE_CONE_FREE;
+}
+
+void balloon_help_destroy( void )
+{
+  assert( b_dpy != NULL );
+  b_dpy = NULL;
+
+  destroy_window( b_dpy, b_win );
+  destroy_gc( b_dpy, b_gc );
+
+  destroy_gc( b_dpy, b_shineGC );
+  destroy_gc( b_dpy, b_shadowGC );
+
+  destroy_pixmap_mask();
+  destroy_gc( b_dpy, b_maskGC );
+
+  if( b_timer ) XtRemoveTimeOut( b_timer );
+}
+
+void balloon_help_set_delay( unsigned long milliseconds )
+{
+  b_delay = milliseconds;
+}
+
+void balloon_help_show( const char* text )
+{
+  assert( b_dpy != NULL );
+
+  /* We don't copy the text */
+  b_text = text;
+  b_lastShape = SHAPE_CONE_FREE;
+
+  if( b_winMapped )
+  {
+    /* If help is already being shown, don't delay just update */
+    show_help( NULL, NULL );
+  }
+  else
+  {
+    b_timer =
+      XtAppAddTimeOut( XtDisplayToApplicationContext(b_dpy),
+                       b_delay, show_help, NULL );
+  }
+}
+
+void balloon_help_hide( void )
+{
+  assert( b_dpy != NULL );
+
+  b_text = NULL;
+  XUnmapWindow( b_dpy, b_win );
+  b_winMapped = False;
+  if( b_timer )
+  {
+    XtRemoveTimeOut( b_timer );
+    b_timer = None;
+  }
+}
+
+void balloon_help_move_to_pointer( void )
+{
+  assert( b_dpy != NULL );
+
+  if( b_winMapped )
+  {
+    int x, y;
+    int shape = b_lastShape;
+
+    get_pointer_xy( b_dpy, &x, &y );
+
+    x += (shape & SHAPE_CONE_LEFT) ? POINTER_OFFSET : -POINTER_OFFSET;
+    y += (shape & SHAPE_CONE_TOP)  ? POINTER_OFFSET : -POINTER_OFFSET;
+
+    shape = get_shape( shape, x, y, b_width, b_height, b_screenWidth, b_screenHeight );
+
+    if( shape == b_lastShape )
+    {
+      b_lastX = x;
+      b_lastY = y;
+
+      XMoveWindow( b_dpy, b_win,
+                   shape & SHAPE_CONE_LEFT ? x : x - b_width,
+                   shape & SHAPE_CONE_TOP  ? y : y - b_height );
+    }
+    else
+    {
+      /* text would be off screen, rebuild with new shape */
+      b_lastShape = SHAPE_CONE_FREE;
+      show_help( NULL, NULL );
+    }
+  }
+}