make precision correct when calling conversion between LttTime and double

[lttv.git] / ltt / branches / poly / lttv / modules / gui / controlflow / drawing.c

/* This file is part of the Linux Trace Toolkit viewer
 * Copyright (C) 2003-2004 Mathieu Desnoyers
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License Version 2 as
 * published by the Free Software Foundation;
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, 
 * MA 02111-1307, USA.
 */

#include <gtk/gtk.h>
#include <gdk/gdk.h>

#include <lttv/lttv.h>
#include <lttv/tracecontext.h>
#include <lttvwindow/lttvwindow.h>
#include <lttv/state.h>
#include <lttv/hook.h>

#include "drawing.h"
#include "eventhooks.h"
#include "cfv.h"
#include "cfv-private.h"

#define g_info(format...) g_log (G_LOG_DOMAIN, G_LOG_LEVEL_INFO, format)
#define g_debug(format...) g_log (G_LOG_DOMAIN, G_LOG_LEVEL_DEBUG, format)

/*****************************************************************************
 *                              drawing functions                            *
 *****************************************************************************/

static gboolean
expose_ruler( GtkWidget *widget, GdkEventExpose *event, gpointer user_data );

static gboolean
motion_notify_ruler(GtkWidget *widget, GdkEventMotion *event, gpointer user_data);


//FIXME Colors will need to be dynamic. Graphic context part not done so far.
typedef enum 
{
  RED,
  GREEN,
  BLUE,
  WHITE,
  BLACK

} ControlFlowColors;

/* Vector of unallocated colors */
static GdkColor CF_Colors [] = 
{
  { 0, 0xffff, 0x0000, 0x0000 },  // RED
  { 0, 0x0000, 0xffff, 0x0000 },  // GREEN
  { 0, 0x0000, 0x0000, 0xffff },  // BLUE
  { 0, 0xffff, 0xffff, 0xffff },  // WHITE
  { 0, 0x0000, 0x0000, 0x0000 } // BLACK
};


/* Function responsible for updating the exposed area.
 * It must do an events request to the lttvwindow API to ask for this update.
 * Note : this function cannot clear the background, because it may
 * erase drawing already present (SAFETY).
 */
void drawing_data_request(Drawing_t *drawing,
      GdkPixmap **pixmap,
      gint x, gint y,
      gint width,
      gint height)
{
  if(width < 0) return ;
  if(height < 0) return ;

  if(drawing->gc == NULL) {
    drawing->gc = gdk_gc_new(drawing->drawing_area->window);
    gdk_gc_copy(drawing->gc, drawing->drawing_area->style->black_gc);
  }


  
  TimeWindow time_window =
              lttvwindow_get_time_window(drawing->control_flow_data->tab);

  ControlFlowData *control_flow_data = drawing->control_flow_data;
  Tab *tab = control_flow_data->tab;
  //    (ControlFlowData*)g_object_get_data(
  //               G_OBJECT(drawing->drawing_area), "control_flow_data");

  LttTime start, time_end;
  LttTime window_end = ltt_time_add(time_window.time_width,
                                    time_window.start_time);

  g_debug("req : window start_time : %u, %u", time_window.start_time.tv_sec, 
                                       time_window.start_time.tv_nsec);

  g_debug("req : window time width : %u, %u", time_window.time_width.tv_sec, 
                                       time_window.time_width.tv_nsec);
  
  g_debug("req : window_end : %u, %u", window_end.tv_sec, 
                                       window_end.tv_nsec);

  g_debug("x is : %i, x+width is : %i", x, x+width);

  convert_pixels_to_time(drawing->width, x,
        time_window.start_time,
        window_end,
        &start);

  convert_pixels_to_time(drawing->width, x+width,
        time_window.start_time,
        window_end,
        &time_end);
  
  EventsRequest *events_request = g_new(EventsRequest, 1);
  // Create the hooks
  LttvHooks *event = lttv_hooks_new();
  LttvHooks *before_chunk_traceset = lttv_hooks_new();
  LttvHooks *after_chunk_traceset = lttv_hooks_new();
  LttvHooks *before_request_hook = lttv_hooks_new();
  LttvHooks *after_request_hook = lttv_hooks_new();

  lttv_hooks_add(before_chunk_traceset,
                 before_chunk,
                 events_request,
                 LTTV_PRIO_DEFAULT);

  lttv_hooks_add(after_chunk_traceset,
                 after_chunk,
                 events_request,
                 LTTV_PRIO_DEFAULT);

  lttv_hooks_add(before_request_hook,
                 before_request,
                 events_request,
                 LTTV_PRIO_DEFAULT);

  lttv_hooks_add(after_request_hook,
                 after_request,
                 events_request,
                 LTTV_PRIO_DEFAULT);


  lttv_hooks_add(event,
                 draw_before_hook,
                 events_request,
                 LTTV_PRIO_STATE-5);
  lttv_hooks_add(event,
                 draw_after_hook,
                 events_request,
                 LTTV_PRIO_STATE+5);

  // Fill the events request
  events_request->owner = control_flow_data;
  events_request->viewer_data = control_flow_data;
  events_request->servicing = FALSE;
  events_request->start_time = start;
  events_request->start_position = NULL;
  events_request->stop_flag = FALSE;
  events_request->end_time = time_end;
  events_request->num_events = G_MAXUINT;
  events_request->end_position = NULL;
  events_request->before_chunk_traceset = before_chunk_traceset;
  events_request->before_chunk_trace = NULL;
  events_request->before_chunk_tracefile = NULL;
  events_request->event = event;
  events_request->event_by_id = NULL;
  events_request->after_chunk_tracefile = NULL;
  events_request->after_chunk_trace = NULL;
  events_request->after_chunk_traceset = after_chunk_traceset;
  events_request->before_request = before_request_hook;
  events_request->after_request = after_request_hook;

  g_debug("req : start : %u, %u", start.tv_sec, 
                                      start.tv_nsec);

  g_debug("req : end : %u, %u", time_end.tv_sec, 
                                     time_end.tv_nsec);

  lttvwindow_events_request_remove_all(tab,
                                       control_flow_data);
  lttvwindow_events_request(tab, events_request);
}
 

static void set_last_start(gpointer key, gpointer value, gpointer user_data)
{
  ProcessInfo *process_info = (ProcessInfo*)key;
  HashedProcessData *hashed_process_data = (HashedProcessData*)value;
  guint x = (guint)user_data;

  hashed_process_data->x = x;

  return;
}

void drawing_data_request_begin(EventsRequest *events_request, LttvTracesetState *tss)
{
  g_debug("Begin of data request");
  ControlFlowData *cfd = events_request->viewer_data;
  LttvTracesetContext *tsc = LTTV_TRACESET_CONTEXT(tss);
  TimeWindow time_window = 
    lttvwindow_get_time_window(cfd->tab);
  LttTime end_time = ltt_time_add(time_window.start_time,
                                    time_window.time_width);
  guint width = cfd->drawing->width;
  guint x=0;

  cfd->drawing->last_start = events_request->start_time;

  convert_time_to_pixels(
          time_window.start_time,
          end_time,
          events_request->start_time,
          width,
          &x);

  g_hash_table_foreach(cfd->process_list->process_hash, set_last_start,
                            (gpointer)x);
}

void drawing_chunk_begin(EventsRequest *events_request, LttvTracesetState *tss)
{
  g_debug("Begin of chunk");
  ControlFlowData *cfd = events_request->viewer_data;
  LttvTracesetContext *tsc = LTTV_TRACESET_CONTEXT(tss);
  LttTime current_time = lttv_traceset_context_get_current_tfc(tsc)->timestamp;

  cfd->drawing->last_start = current_time;
}


void drawing_request_expose(EventsRequest *events_request,
                            LttvTracesetState *tss,
                            LttTime end_time)
{
  gint x, x_end, width;

  ControlFlowData *cfd = events_request->viewer_data;
  LttvTracesetContext *tsc = LTTV_TRACESET_CONTEXT(tss);
  Drawing_t *drawing = cfd->drawing;
  
  TimeWindow time_window = 
        lttvwindow_get_time_window(cfd->tab);

  g_debug("request expose");
  
  LttTime window_end = ltt_time_add(time_window.time_width,
                                    time_window.start_time);

  convert_time_to_pixels(
        time_window.start_time,
        window_end,
        cfd->drawing->last_start,
        drawing->width,
        &x);

  convert_time_to_pixels(
        time_window.start_time,
        window_end,
        end_time,
        drawing->width,
        &x_end);

  width = x_end - x;

  drawing->damage_begin = x+width;
  //drawing->damage_end = drawing->width;

  /* ask for the buffer to be redrawn */

  //gtk_widget_queue_draw_area ( drawing->drawing_area,
  //                             0, 0,
  //                             drawing->width, drawing->height);

  /* FIXME
   * will need more precise pixel_to_time and time_to_pixel conversion
   * functions to redraw only the needed area. */
  gtk_widget_queue_draw_area ( drawing->drawing_area,
                               x, 0,
                               width, drawing->height);
 
}


/* Callbacks */


/* Create a new backing pixmap of the appropriate size */
/* As the scaling will always change, it's of no use to copy old
 * pixmap.
 *
 * Only change the size if width changes. The height is specified and changed
 * when process ID are added or removed from the process list.
 */
static gboolean
configure_event( GtkWidget *widget, GdkEventConfigure *event, 
    gpointer user_data)
{
  Drawing_t *drawing = (Drawing_t*)user_data;


  /* First, get the new time interval of the main window */
  /* we assume (see documentation) that the main window
   * has updated the time interval before this configure gets
   * executed.
   */
  //lttvwindow_get_time_window(drawing->control_flow_data->mw,
  //      &drawing->control_flow_data->time_window);
  
  /* New pixmap, size of the configure event */
  //GdkPixmap *pixmap = gdk_pixmap_new(widget->window,
  //      widget->allocation.width + SAFETY,
  //      widget->allocation.height + SAFETY,
  //      -1);
  
  if(widget->allocation.width != drawing->width) {
    g_debug("drawing configure event");
    g_debug("New alloc draw size : %i by %i",widget->allocation.width,
                                    widget->allocation.height);
  
    
    if (drawing->pixmap)
      gdk_pixmap_unref(drawing->pixmap);
  
    drawing->width = widget->allocation.width;
    //drawing->height = widget->allocation.height;

    drawing->pixmap = gdk_pixmap_new(widget->window,
                                     drawing->width + SAFETY,
                                     drawing->height,
                                     -1);
    //ProcessList_get_height
    // (GuiControlFlow_get_process_list(drawing->control_flow_data)),
    

    // Clear the image
    gdk_draw_rectangle (drawing->pixmap,
          widget->style->black_gc,
          TRUE,
          0, 0,
          drawing->width+SAFETY,
          drawing->height);

    //g_info("init data request");


    /* Initial data request */
    /* no, do initial data request in the expose event */
    // Do not need to ask for data of 1 pixel : not synchronized with
    // main window time at this moment.
    //drawing_data_request(drawing, &drawing->pixmap, 0, 0,
    //    widget->allocation.width,
    //    widget->allocation.height);
                          
    //drawing->width = widget->allocation.width;
    //drawing->height = widget->allocation.height;
  
    drawing->damage_begin = 0;
    drawing->damage_end = widget->allocation.width;

    if(drawing->damage_begin < drawing->damage_end)
    {
      drawing_data_request(drawing,
                           &drawing->pixmap,
                           drawing->damage_begin,
                           0,
                           drawing->damage_end - drawing->damage_begin,
                           drawing->height);
    }
  }
  return TRUE;
}


/* Redraw the screen from the backing pixmap */
static gboolean
expose_event( GtkWidget *widget, GdkEventExpose *event, gpointer user_data )
{
  Drawing_t *drawing = (Drawing_t*)user_data;

  ControlFlowData *control_flow_data =
      (ControlFlowData*)g_object_get_data(
                G_OBJECT(widget),
                "control_flow_data");

  TimeWindow time_window = 
      lttvwindow_get_time_window(control_flow_data->tab);
  LttTime current_time = 
      lttvwindow_get_current_time(control_flow_data->tab);

  guint cursor_x=0;

  LttTime window_end = ltt_time_add(time_window.time_width,
                                    time_window.start_time);

  convert_time_to_pixels(
        time_window.start_time,
        window_end,
        current_time,
        drawing->width,
        &cursor_x);

 
  /* update the screen from the pixmap buffer */
  gdk_draw_pixmap(widget->window,
      widget->style->fg_gc[GTK_WIDGET_STATE (widget)],
      drawing->pixmap,
      event->area.x, event->area.y,
      event->area.x, event->area.y,
      event->area.width, event->area.height);


  /* Draw the dotted lines */

  if(drawing->dotted_gc == NULL) {

    drawing->dotted_gc = gdk_gc_new(drawing->drawing_area->window);
    gdk_gc_copy(drawing->dotted_gc, widget->style->white_gc);
 
    gint8 dash_list[] = { 1, 2 };
    gdk_gc_set_line_attributes(drawing->dotted_gc,
                               1,
                               GDK_LINE_ON_OFF_DASH,
                               GDK_CAP_BUTT,
                               GDK_JOIN_MITER);
    gdk_gc_set_dashes(drawing->dotted_gc,
                      0,
                      dash_list,
                      2);
  }

  drawing_draw_line(NULL, widget->window,
                cursor_x, 0,
                cursor_x, drawing->height,
                drawing->dotted_gc);
  return FALSE;
}

static gboolean
after_expose_event( GtkWidget *widget, GdkEventExpose *event, gpointer user_data )
{
  //g_assert(0);
  g_debug("AFTER EXPOSE");

  return FALSE;


}


/* mouse click */
static gboolean
button_press_event( GtkWidget *widget, GdkEventButton *event, gpointer user_data )
{
  ControlFlowData *control_flow_data =
      (ControlFlowData*)g_object_get_data(
                G_OBJECT(widget),
                "control_flow_data");
  Drawing_t *drawing = control_flow_data->drawing;
  TimeWindow time_window =
               lttvwindow_get_time_window(control_flow_data->tab);

  g_debug("click");
  if(event->button == 1)
  {
    LttTime time;

    LttTime window_end = ltt_time_add(time_window.time_width,
                                      time_window.start_time);


    /* left mouse button click */
    g_debug("x click is : %f", event->x);

    convert_pixels_to_time(drawing->width, (guint)event->x,
        time_window.start_time,
        window_end,
        &time);

    lttvwindow_report_current_time(control_flow_data->tab, &time);

  }

  lttvwindow_report_focus(control_flow_data->tab,
           gtk_widget_get_parent(guicontrolflow_get_widget(control_flow_data)));

  return FALSE;
}

static gboolean
scrollbar_size_allocate(GtkWidget *widget,
                        GtkAllocation *allocation,
                        gpointer user_data)
{
  Drawing_t *drawing = (Drawing_t*)user_data;

  gtk_widget_set_size_request(drawing->padding, allocation->width, -1);
  //gtk_widget_queue_resize(drawing->padding);
  //gtk_widget_queue_resize(drawing->ruler);
  gtk_container_check_resize(GTK_CONTAINER(drawing->ruler_hbox));
  return 0;
}



Drawing_t *drawing_construct(ControlFlowData *control_flow_data)
{
  Drawing_t *drawing = g_new(Drawing_t, 1);
  
  drawing->control_flow_data = control_flow_data;

  drawing->vbox = gtk_vbox_new(FALSE, 1);

  
  drawing->ruler_hbox = gtk_hbox_new(FALSE, 1);
  drawing->ruler = gtk_drawing_area_new ();
  gtk_widget_add_events(drawing->ruler, GDK_BUTTON_PRESS_MASK);
  //gtk_widget_set_size_request(drawing->ruler, -1, 27);
  
  drawing->padding = gtk_drawing_area_new ();
  gtk_widget_add_events(drawing->padding, GDK_BUTTON_PRESS_MASK);
  //gtk_widget_set_size_request(drawing->padding, -1, 27);
  gtk_box_pack_start(GTK_BOX(drawing->ruler_hbox), drawing->ruler, 
                     TRUE, TRUE, 0);
  gtk_box_pack_end(GTK_BOX(drawing->ruler_hbox), drawing->padding, 
                     FALSE, FALSE, 0);
  


  drawing->drawing_area = gtk_drawing_area_new ();
  
  drawing->gc = NULL;
  
  drawing->hbox = gtk_hbox_new(FALSE, 1);
  drawing->viewport = gtk_viewport_new(NULL, control_flow_data->v_adjust);
  drawing->scrollbar = gtk_vscrollbar_new(control_flow_data->v_adjust);
  gtk_box_pack_start(GTK_BOX(drawing->hbox), drawing->viewport, 
                     TRUE, TRUE, 0);
  gtk_box_pack_end(GTK_BOX(drawing->hbox), drawing->scrollbar, 
                     FALSE, FALSE, 0);
  
  //drawing->scrolled_window =
  //    gtk_scrolled_window_new (NULL,
  //    control_flow_data->v_adjust);
  
  //gtk_scrolled_window_set_policy(
  //  GTK_SCROLLED_WINDOW(drawing->scrolled_window),
  //  GTK_POLICY_NEVER,
  //  GTK_POLICY_AUTOMATIC);

  gtk_container_add(GTK_CONTAINER(drawing->viewport),
                    drawing->drawing_area);
  //gtk_scrolled_window_add_with_viewport(
  //  GTK_SCROLLED_WINDOW(drawing->scrolled_window),
  //  drawing->drawing_area);

  gtk_box_pack_start(GTK_BOX(drawing->vbox), drawing->ruler_hbox, 
                     FALSE, FALSE, 0);
  gtk_box_pack_end(GTK_BOX(drawing->vbox), drawing->hbox,
                   TRUE, TRUE, 0);
  
  drawing->pango_layout =
    gtk_widget_create_pango_layout(drawing->drawing_area, NULL);

  drawing->dotted_gc = NULL;

  drawing->height = 1;
  drawing->width = 1;
  drawing->depth = 0;
  
  drawing->damage_begin = 0;
  drawing->damage_end = 0;
  
  //gtk_widget_set_size_request(drawing->drawing_area->window, 50, 50);
  g_object_set_data_full(
      G_OBJECT(drawing->drawing_area),
      "Link_drawing_Data",
      drawing,
      (GDestroyNotify)drawing_destroy);

  g_object_set_data(
      G_OBJECT(drawing->ruler),
      "drawing",
      drawing);


  //gtk_widget_modify_bg( drawing->drawing_area,
  //      GTK_STATE_NORMAL,
  //      &CF_Colors[BLACK]);
  
  //gdk_window_get_geometry(drawing->drawing_area->window,
  //    NULL, NULL,
  //    &(drawing->width),
  //    &(drawing->height),
  //    -1);
  
  //drawing->pixmap = gdk_pixmap_new(
  //    drawing->drawing_area->window,
  //    drawing->width,
  //    drawing->height,
  //    drawing->depth);
  
  drawing->pixmap = NULL;

//  drawing->pixmap = gdk_pixmap_new(drawing->drawing_area->window,
//        drawing->drawing_area->allocation.width,
//        drawing->drawing_area->allocation.height,
//        -1);

  gtk_widget_add_events(drawing->drawing_area, GDK_BUTTON_PRESS_MASK);
  
  g_signal_connect (G_OBJECT(drawing->drawing_area),
        "configure_event",
        G_CALLBACK (configure_event),
        (gpointer)drawing);
 
  g_signal_connect (G_OBJECT(drawing->ruler),
        "expose_event",
        G_CALLBACK(expose_ruler),
        (gpointer)drawing);

  gtk_widget_add_events(drawing->ruler, GDK_POINTER_MOTION_MASK);

  g_signal_connect (G_OBJECT(drawing->ruler),
        "motion-notify-event",
        G_CALLBACK(motion_notify_ruler),
        (gpointer)drawing);


  g_signal_connect (G_OBJECT(drawing->scrollbar),
        "size-allocate",
        G_CALLBACK(scrollbar_size_allocate),
        (gpointer)drawing);



  g_signal_connect (G_OBJECT(drawing->drawing_area),
        "expose_event",
        G_CALLBACK (expose_event),
        (gpointer)drawing);

  g_signal_connect_after (G_OBJECT(drawing->drawing_area),
        "expose_event",
        G_CALLBACK (after_expose_event),
        (gpointer)drawing);

  g_signal_connect (G_OBJECT(drawing->drawing_area),
        "button-press-event",
        G_CALLBACK (button_press_event),
        (gpointer)drawing);
  
  gtk_widget_show(drawing->ruler);
  gtk_widget_show(drawing->padding);
  gtk_widget_show(drawing->ruler_hbox);

  gtk_widget_show(drawing->drawing_area);
  //gtk_widget_show(drawing->scrolled_window);
  gtk_widget_show(drawing->viewport);
  gtk_widget_show(drawing->scrollbar);
  gtk_widget_show(drawing->hbox);

  
  return drawing;
}

void drawing_destroy(Drawing_t *drawing)
{
  g_info("drawing_destroy %p", drawing);
  // Do not unref here, Drawing_t destroyed by it's widget.
  //g_object_unref( G_OBJECT(drawing->drawing_area));
  if(drawing->gc != NULL)
    gdk_gc_unref(drawing->gc);
  
  g_free(drawing->pango_layout);
  if(!drawing->dotted_gc) gdk_gc_unref(drawing->dotted_gc);
  g_free(drawing);
  g_info("drawing_destroy end");
}

GtkWidget *drawing_get_drawing_area(Drawing_t *drawing)
{
  return drawing->drawing_area;
}

GtkWidget *drawing_get_widget(Drawing_t *drawing)
{
  return drawing->vbox;
}

/* convert_pixels_to_time
 *
 * Convert from window pixel and time interval to an absolute time.
 */
//FIXME : could need ceil and floor versions of this function
void convert_pixels_to_time(
    gint width,
    guint x,
    LttTime window_time_begin,
    LttTime window_time_end,
    LttTime *time)
{
  LttTime window_time_interval;
  
  window_time_interval = ltt_time_sub(window_time_end, 
            window_time_begin);
  *time = ltt_time_mul(window_time_interval, (x/(float)width));
  *time = ltt_time_add(window_time_begin, *time);
}

//FIXME : could need ceil and floor versions of this function

void convert_time_to_pixels(
    LttTime window_time_begin,
    LttTime window_time_end,
    LttTime time,
    int width,
    guint *x)
{
  LttTime window_time_interval;
  double interval_double, time_double;
  
  window_time_interval = ltt_time_sub(window_time_end,window_time_begin);
  
  time = ltt_time_sub(time, window_time_begin);
  
  /* LttTime to double conversions here should really be under 4000 hours.. */
  interval_double = ltt_time_to_double(window_time_interval);
  time_double = ltt_time_to_double(time);

  *x = (guint)(time_double/interval_double * width);
  
}

void drawing_draw_line( Drawing_t *drawing,
      GdkPixmap *pixmap,
      guint x1, guint y1,
      guint x2, guint y2,
      GdkGC *GC)
{
  gdk_draw_line (pixmap,
      GC,
      x1, y1, x2, y2);
}

void drawing_clear(Drawing_t *drawing)
{ 
  if (drawing->pixmap)
    gdk_pixmap_unref(drawing->pixmap);

  drawing->height = 1;
  /* Allocate a new pixmap with new height */
  drawing->pixmap = gdk_pixmap_new(drawing->drawing_area->window,
                                   drawing->width + SAFETY,
                                   drawing->height,
                                     -1);

  gtk_widget_set_size_request(drawing->drawing_area,
                             -1,
                             drawing->height);
  gtk_widget_queue_resize_no_redraw(drawing->drawing_area);
  
  /* ask for the buffer to be redrawn */
  gtk_widget_queue_draw_area ( drawing->drawing_area,
                               0, 0,
                               drawing->width, drawing->height);
}


/* Insert a square corresponding to a new process in the list */
/* Applies to whole drawing->width */
void drawing_insert_square(Drawing_t *drawing,
        guint y,
        guint height)
{
  //GdkRectangle update_rect;

  /* Allocate a new pixmap with new height */
  GdkPixmap *pixmap = gdk_pixmap_new(drawing->drawing_area->window,
        drawing->width + SAFETY,
        drawing->height + height,
        -1);
  
  /* Copy the high region */
  gdk_draw_drawable (pixmap,
    drawing->drawing_area->style->black_gc,
    drawing->pixmap,
    0, 0,
    0, 0,
    drawing->width + SAFETY, y);




  /* add an empty square */
  gdk_draw_rectangle (pixmap,
    drawing->drawing_area->style->black_gc,
    TRUE,
    0, y,
    drawing->width + SAFETY,  // do not overlap
    height);



  /* copy the bottom of the region */
  gdk_draw_drawable (pixmap,
    drawing->drawing_area->style->black_gc,
    drawing->pixmap,
    0, y,
    0, y + height,
    drawing->width+SAFETY, drawing->height - y);


  if (drawing->pixmap)
    gdk_pixmap_unref(drawing->pixmap);

  drawing->pixmap = pixmap;
  
  if(drawing->height==1) drawing->height = height;
  else drawing->height += height;
  
  gtk_widget_set_size_request(drawing->drawing_area,
                             -1,
                             drawing->height);
  gtk_widget_queue_resize_no_redraw(drawing->drawing_area);
  
  /* ask for the buffer to be redrawn */
  gtk_widget_queue_draw_area ( drawing->drawing_area,
                               0, y,
                               drawing->width, drawing->height-y);
}


/* Remove a square corresponding to a removed process in the list */
void drawing_remove_square(Drawing_t *drawing,
        guint y,
        guint height)
{
  GdkPixmap *pixmap;

  if(drawing->height == height) {
    pixmap = gdk_pixmap_new(
        drawing->drawing_area->window,
        drawing->width + SAFETY,
        1,
        -1);
    drawing->height=1;
  } else {
    /* Allocate a new pixmap with new height */
     pixmap = gdk_pixmap_new(
        drawing->drawing_area->window,
        drawing->width + SAFETY,
        drawing->height - height,
        -1);
   
    /* Copy the high region */
    gdk_draw_drawable (pixmap,
      drawing->drawing_area->style->black_gc,
      drawing->pixmap,
      0, 0,
      0, 0,
      drawing->width + SAFETY, y);

    /* Copy up the bottom of the region */
    gdk_draw_drawable (pixmap,
      drawing->drawing_area->style->black_gc,
      drawing->pixmap,
      0, y + height,
      0, y,
      drawing->width, drawing->height - y - height);

    drawing->height-=height;
  }

  if (drawing->pixmap)
    gdk_pixmap_unref(drawing->pixmap);

  drawing->pixmap = pixmap;
  
  gtk_widget_set_size_request(drawing->drawing_area,
                             -1,
                             drawing->height);
  gtk_widget_queue_resize_no_redraw(drawing->drawing_area);
  /* ask for the buffer to be redrawn */
  gtk_widget_queue_draw_area ( drawing->drawing_area,
                               0, y,
                               drawing->width, MAX(drawing->height-y, 1));
}

void drawing_update_ruler(Drawing_t *drawing, TimeWindow *time_window)
{
  GtkRequisition req;
  GdkRectangle rect;
  
  req.width = drawing->ruler->allocation.width;
  req.height = drawing->ruler->allocation.height;

 
  rect.x = 0;
  rect.y = 0;
  rect.width = req.width;
  rect.height = req.height;

  gtk_widget_queue_draw(drawing->ruler);
  //gtk_widget_draw( drawing->ruler, &rect);
}

/* Redraw the ruler */
static gboolean
expose_ruler( GtkWidget *widget, GdkEventExpose *event, gpointer user_data )
{
  Drawing_t *drawing = (Drawing_t*)user_data;
  TimeWindow time_window = lttvwindow_get_time_window(drawing->control_flow_data->tab);
  gchar text[255];
  
  PangoContext *context;
  PangoLayout *layout;
  PangoAttribute *attribute;
  PangoFontDescription *FontDesc;
  gint Font_Size;
  PangoRectangle ink_rect;
  guint global_width=0;
  GdkColor foreground = { 0, 0, 0, 0 };
  GdkColor background = { 0, 0xffff, 0xffff, 0xffff };

  LttTime window_end = 
    ltt_time_add(time_window.time_width,
                 time_window.start_time);
  LttTime half_width =
    ltt_time_div(time_window.time_width,2.0);
  LttTime window_middle =
    ltt_time_add(half_width,
                 time_window.start_time);
  g_debug("ruler expose event");
 
  gdk_draw_rectangle (drawing->ruler->window,
          drawing->ruler->style->white_gc,
          TRUE,
          event->area.x, event->area.y,
          event->area.width,
          event->area.height);

   GdkGC *gc = gdk_gc_new(drawing->ruler->window);
   gdk_gc_copy(gc, drawing->ruler->style->black_gc);
   gdk_gc_set_line_attributes(gc,
                               2,
                               GDK_LINE_SOLID,
                               GDK_CAP_BUTT,
                               GDK_JOIN_MITER);
  gdk_draw_line (drawing->ruler->window,
                  gc,
                  event->area.x, 1,
                  event->area.x + event->area.width, 1);


  snprintf(text, 255, "%lus\n%luns",
    time_window.start_time.tv_sec,
    time_window.start_time.tv_nsec);

  layout = gtk_widget_create_pango_layout(drawing->drawing_area, NULL);

  context = pango_layout_get_context(layout);
  FontDesc = pango_context_get_font_description(context);

  pango_font_description_set_size(FontDesc, 6*PANGO_SCALE);
  pango_layout_context_changed(layout);

  pango_layout_set_text(layout, text, -1);
  pango_layout_get_pixel_extents(layout, &ink_rect, NULL);
  global_width += ink_rect.width;

  gdk_draw_layout_with_colors(drawing->ruler->window,
      gc,
      0,
      6,
      layout, &foreground, &background);

  gdk_gc_set_line_attributes(gc,
                             2,
                             GDK_LINE_SOLID,
                             GDK_CAP_ROUND,
                             GDK_JOIN_ROUND);

  gdk_draw_line (drawing->ruler->window,
                   gc,
                   1, 1,
                   1, 7);


  snprintf(text, 255, "%lus\n%luns", window_end.tv_sec,
                                     window_end.tv_nsec);

  pango_layout_set_text(layout, text, -1);
  pango_layout_get_pixel_extents(layout, &ink_rect, NULL);
  global_width += ink_rect.width;

  if(global_width <= drawing->ruler->allocation.width)
  {
    gdk_draw_layout_with_colors(drawing->ruler->window,
      gc,
      drawing->ruler->allocation.width - ink_rect.width,
      6,
      layout, &foreground, &background);

    gdk_gc_set_line_attributes(gc,
                               2,
                               GDK_LINE_SOLID,
                               GDK_CAP_ROUND,
                               GDK_JOIN_ROUND);

    gdk_draw_line (drawing->ruler->window,
                   gc,
                   drawing->ruler->allocation.width-1, 1,
                   drawing->ruler->allocation.width-1, 7);
  }


  snprintf(text, 255, "%lus\n%luns", window_middle.tv_sec,
                                     window_middle.tv_nsec);

  pango_layout_set_text(layout, text, -1);
  pango_layout_get_pixel_extents(layout, &ink_rect, NULL);
  global_width += ink_rect.width;

  if(global_width <= drawing->ruler->allocation.width)
  {
    gdk_draw_layout_with_colors(drawing->ruler->window,
      gc,
      (drawing->ruler->allocation.width - ink_rect.width)/2,
      6,
      layout, &foreground, &background);

    gdk_gc_set_line_attributes(gc,
                               2,
                               GDK_LINE_SOLID,
                               GDK_CAP_ROUND,
                               GDK_JOIN_ROUND);

    gdk_draw_line (drawing->ruler->window,
                   gc,
                   drawing->ruler->allocation.width/2, 1,
                   drawing->ruler->allocation.width/2, 7);




  }

  gdk_gc_unref(gc);
  g_object_unref(layout);
   
  return FALSE;
}


/* notify mouse on ruler */
static gboolean
motion_notify_ruler(GtkWidget *widget, GdkEventMotion *event, gpointer user_data)
{
  //g_debug("motion");
  //eventually follow mouse and show time here
}