chunkview.c

/*
 * Copyright (C) 2002 2003 2004 2005 2007 2008 2009 2010, Magnus Hjorth
 *
 * This file is part of mhWaveEdit.
 *
 * mhWaveEdit is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by        
 * the Free Software Foundation; either version 2 of the License, or  
 * (at your option) any later version.
 *
 * mhWaveEdit 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 mhWaveEdit; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */


#include <config.h>



#include <math.h>
#include "chunkview.h"
#include "main.h"
#include "inifile.h"
#include "player.h"
#include "mainloop.h"

G_DEFINE_TYPE(ChunkView,chunk_view,GTK_TYPE_DRAWING_AREA)

static guint font_height=0,font_width=0;

enum { VIEW_CHANGED_SIGNAL, SELECTION_CHANGED_SIGNAL, CURSOR_CHANGED_SIGNAL, 
       CHUNK_CHANGED_SIGNAL, DOUBLE_CLICK_SIGNAL, LAST_SIGNAL };
static guint chunk_view_signals[LAST_SIGNAL] = { 0 };

static void chunk_view_update_image(ChunkView *view, guint xs, guint xe);
static void chunk_view_redraw_samples(ChunkView *cv, off_t start, off_t end);
static gint calc_x(ChunkView *cv, off_t sample, off_t width);
static int chunk_view_autoscroll(gpointer timesource, gint64 current_time,
				 gpointer user_data);

static void chunk_view_changed(Document *d, gpointer user_data)
{
     ChunkView *cv = CHUNKVIEW(user_data);
     if (cv->image != NULL) 
	  chunk_view_update_image(cv,0,cv->image_width-1);
     gtk_widget_queue_draw(GTK_WIDGET(cv));
}

static void chunk_view_selection_changed(Document *d, gpointer user_data)
{
     off_t os,oe,ns,ne;

     ChunkView *cv = CHUNKVIEW(user_data);

     /* Calculate the user-visible part of the old selection */
     os = MAX(d->viewstart, d->old_selstart);
     oe = MIN(d->viewend,   d->old_selend);
     
     /* Calculate user-visible part of the new selection */
     ns = MAX(d->viewstart, d->selstart);
     ne = MIN(d->viewend,   d->selend);

     /* Different cases:
      *  1. Neither the old nor the new selection is in view.
      *  2. The old selection wasn't in view but the new is..
      *  3. The new selection is in view but the old wasn't..
      *  4. Both are in view and overlap
      *  5. Both are in view and don't overlap
      */

     if (os >= oe && ns >= ne) {
	  /* Case 1 - Do nothing */
     } else if (os >= oe) {
	  /* Case 2 - Draw the entire new sel. */
	  chunk_view_redraw_samples(cv,ns,ne);
     } else if (ns >= ne) {
	  /* Case 3 - Redraw the old sel. */
	  chunk_view_redraw_samples(cv,os,oe);
     } else if ((ns >= os && ns < oe) || (os >= ns && os < ne)) {
	  /* Case 4 - Redraw the changes on both sides */
	  if (os != ns)
	       chunk_view_redraw_samples(cv,MIN(os,ns),MAX(os,ns));
	  if (oe != ne)
	       chunk_view_redraw_samples(cv,MIN(oe,ne),MAX(oe,ne));
     } else {
	  /* Case 5 - Redraw both selections */
	  chunk_view_redraw_samples(cv,os,oe);
	  chunk_view_redraw_samples(cv,ns,ne);
     }
     
}

static void chunk_view_cursor_changed(Document *d, gboolean rolling, 
				      gpointer user_data)
{     
     ChunkView *cv = CHUNKVIEW(user_data);
     off_t pos[4];
     int npos,pix[4],npix,i,w=GTK_WIDGET(cv)->allocation.width;

     npos = 0;
     pos[npos++] = d->old_cursorpos;
     pos[npos++] = d->cursorpos;
     if (cv->show_bufpos) {
	  pos[npos++] = d->old_playbufpos;
	  pos[npos++] = d->playbufpos;
     }
     npix = npos;
     for (i=0; i<npos; i++)
	  pix[i]=calc_x(cv,pos[i],w);
     while (npix > 0 && pix[0] == pix[1]) {
	  pix[0] = pix[2]; pix[1] = pix[3];
	  npix -= 2;
     }
     for (i=0; i<npix; i++) {
	  if (pix[i] > -1 && pix[i] < w)
	       gtk_widget_queue_draw_area(GTK_WIDGET(cv),pix[i],0,1,
					  cv->image_height);
     }
}

static void chunk_view_destroy (GtkObject *object)
{
     ChunkView *cv = CHUNKVIEW(object);
     if (cv->image) {
	  gdk_pixmap_unref(cv->image);
	  cv->image = NULL;
     }
     if (cv->doc != NULL) {
	  g_signal_handlers_disconnect_matched(cv->doc, G_SIGNAL_MATCH_DATA,
	                                       0, 0, NULL, NULL, cv);
	  gtk_object_unref(GTK_OBJECT(cv->doc));
     }
     cv->doc = NULL;
     GTK_OBJECT_CLASS(chunk_view_parent_class)->destroy(object);
     if (cv->cache) view_cache_free(cv->cache);
     cv->cache = NULL;
}

static gint calc_x(ChunkView *cv, off_t sample, off_t width)
{
     Document *d = cv->doc;
     gfloat f,g;
     if (sample < d->viewstart)
	  return -1;
     if (sample > d->viewend )
	  return width;
     else {
	  f = sample - d->viewstart;
	  g = d->viewend - d->viewstart;
	  return width * (f/g);
     }
}

static gint calc_x_noclamp(ChunkView *cv, off_t sample, off_t width)
{
     Document *d = cv->doc;
     gfloat f,g;

     f = sample - d->viewstart;
     g = d->viewend - d->viewstart;
     return width * (f/g);
}


static void chunk_view_update_image_main(ChunkView *cv, GdkDrawable *image,
					 guint xs, guint xe)
{
     int i,j,y;
     gint w,h;
     GtkWidget *wid = GTK_WIDGET(cv);
     Document *d = cv->doc;
     w = wid->allocation.width;
     h = wid->allocation.height;
     if (cv->timescale) h-=font_height;
     if (xe < xs) return;
     /* Svart bakgrund */
     gdk_draw_rectangle( image, get_gc(BACKGROUND,wid), TRUE, xs, 0, 
			 1+xe-xs,h);
     /* Om det inte finns någon sampling laddad, stanna här. */
     if (d == NULL || d->chunk->length == 0) return;
     /* Rita ut markeringen med speciell färg */
     if (d->selstart != d->selend && d->selstart < d->viewend &&
	 d->selend > d->viewstart) {
	  if (d->selstart > d->viewstart)
	       i = calc_x( cv, d->selstart, w );
	  else 
	       i = 0;
	  if (i < xs) i=xs;
	  if (i <= xe) {
	       if (d->selend < d->viewend)
		    j = calc_x( cv, d->selend, w );
	       else
		    j = xe;
	       if (j > xe) j = xe;
	       if (j >= xs) {
		    gdk_draw_rectangle( image, get_gc(SELECTION,wid),TRUE, 
					i, 0, 1+j-i, h );
	       }
	  }
	  
	  // printf("i = %d, j = %d\n",i,j);
     }
     /* Rita gråa streck */
     j = h/d->chunk->format.channels;
     for (i=0; i<d->chunk->format.channels; i++) {
	  y = j/2 + i*j;	  
	  gdk_draw_line(image,get_gc(BARS,wid),xs,y,xe,y);
     }
     /* Drawing one pixel to the left of xs is a workaround. Some part of the
      * code seems to draw one pixel wrong to the left. */
     view_cache_draw_part(cv->cache, image, (xs==0)?0:xs-1, xe, h, 
			  GTK_WIDGET(cv),
			  cv->scale_factor);
}

static void chunk_view_update_image(ChunkView *cv, guint xs, guint xe)
{
}

struct draw_mark_data {
     ChunkView *view;
     GdkEventExpose *event;
};

static void draw_mark(gchar *label, off_t position, gpointer user_data)
{
     struct draw_mark_data *dd = (struct draw_mark_data *)user_data;
     ChunkView *cv = dd->view;
     GdkEventExpose *event = dd->event;
     GtkWidget *widget = GTK_WIDGET(cv);
     Document *d = cv->doc;
     guint i;

     if ( position >= d->viewstart && position <= d->viewend ) {
	  i = calc_x( cv, position, widget->allocation.width );
	  if (event->area.x <= i+10 && event->area.x+event->area.width > i) {
	       gdk_draw_line( widget->window, get_gc(MARK,widget), i, 
			      event->area.y, i, 
			      event->area.y+event->area.height-1);
	       /* Render the text */
	       gdk_gc_set_foreground(widget->style->fg_gc[0],get_color(MARK));
	       gtk_draw_string( widget->style, widget->window, 
				GTK_STATE_NORMAL, i+2, font_height+2, label );
	       gdk_gc_set_foreground(widget->style->fg_gc[0],get_color(BLACK));
/*	       gdk_draw_text( widget->window, widget->style->font, 
			      gc_mark(widget), i+2, 12, (gchar *)key, 
			      strlen(key) ); */
	  }
     }
}

static void draw_time_bars(ChunkView *view, GdkEventExpose *event, 
			   off_t *points, int npoints, 
			   off_t *ignpoints, int nignpoints,
			   gboolean small, gint text)
{
     char buf[32];
     gint c,i,j;
     PangoLayout *pl;
     GtkWidget *widget = GTK_WIDGET(view);
     Document *d = view->doc;
     char *s;
     int ignctr = 0;
     
     for (c=0; c<npoints; c++) {
	  
	  while (ignctr < nignpoints && ignpoints[ignctr] < points[c])
	       ignctr++;
	  if (ignctr < nignpoints && ignpoints[ignctr] == points[c]) 
	       continue;

	  j = calc_x_noclamp(view, points[c], widget->allocation.width);

	  /* printf("draw_time_bars: f=%f, h=%f\n",f,h); */
	  gdk_draw_line( widget->window, widget->style->white_gc, j, 
			 widget->allocation.height-font_height-(small?3:7), 
			 j, widget->allocation.height-font_height);

	  if (text >= 0) {

	       if (text > 0)
		    s = get_time_tail(view->doc->chunk->format.samplerate, 
				      points[c], d->chunk->length,
				      buf, default_timescale_mode);
	       else 
		    s = get_time_head(d->chunk->format.samplerate, 
				      points[c], d->chunk->length,
				      buf, default_timescale_mode);

	       if (s == NULL) continue;
	       
	       /* puts(buf); */
	       pl = gtk_widget_create_pango_layout( widget, buf );
	       pango_layout_get_pixel_size(pl, &i, NULL);
	       gdk_draw_layout( widget->window, widget->style->fg_gc[GTK_STATE_NORMAL],
				j-i/2, widget->allocation.height-font_height,
				pl);
	       g_object_unref(G_OBJECT(pl));
	  }
     } 
}

static void draw_timescale(ChunkView *view, GdkEventExpose *event, gboolean text)
{
     GtkWidget *widget = GTK_WIDGET(view);
     Document *d = view->doc;
     guint i;

     off_t *points,*midpoints,*minorpoints;
     int npoints,nmidpoints,nminorpoints;

     guint midtext,minortext;

     if (text) gdk_window_clear_area(widget->window, event->area.x, 
				     view->image_height,event->area.width,
				     font_height);


     /* Draw the horizontal line */
     i = widget->allocation.height-font_height;
     gdk_draw_line( widget->window, widget->style->white_gc, event->area.x, 
		    i, event->area.x+event->area.width-1, i);
     /* pixels/sec */

     /* We want at least font_width pixels/major point 
      * and 8 pixels/minor point*/
     npoints = widget->allocation.width / font_width + 1;
     if (npoints < 3) npoints = 3;
     nmidpoints = npoints;
     nminorpoints = widget->allocation.width / 8 + 1;
     if (nminorpoints < npoints) nminorpoints = npoints;
     points = g_malloc(npoints * sizeof(off_t));
     midpoints = g_malloc(nmidpoints * sizeof(off_t));
     minorpoints = g_malloc(nminorpoints * sizeof(off_t));

     minortext = find_timescale_points(d->chunk->format.samplerate, 
				       d->viewstart, d->viewend, 
				       points, &npoints,
				       midpoints, &nmidpoints,
				       minorpoints, &nminorpoints,
				       default_timescale_mode);
			   
     /*
     printf("npoints: %d, pixels/point: %d\n",npoints,
	    widget->allocation.width / npoints); 
     printf("nmidpoints: %d, pixels/midpoint: %d\n",nmidpoints,
	    (nmidpoints > 0) ? widget->allocation.width / nmidpoints : 0); 
     printf("nminorpoints: %d, pixels/minorpoint: %d\n",nminorpoints,
	    (nminorpoints > 0) ? widget->allocation.width / nminorpoints : 0); 
     printf("font_width: %d\n",font_width);
     */

     midtext = minortext;

     if (nminorpoints > 0 && 
	 (widget->allocation.width / nminorpoints) < font_width) 
	  minortext = -1;
     else
	  midtext = -1;

     draw_time_bars(view,event,points,npoints,NULL,0,FALSE,text ? 0 : -1);

     if (midtext >= 0) {
	  draw_time_bars(view,event,midpoints,nmidpoints,points,npoints,FALSE,
			 text ? midtext : -1);
     }

     draw_time_bars(view,event,minorpoints,nminorpoints,points,npoints,TRUE,
		    text ? minortext : -1);

     g_free(points);
     g_free(minorpoints);
}

static gint chunk_view_expose(GtkWidget *widget, GdkEventExpose *event)
{
     ChunkView *cv = CHUNKVIEW(widget);
     Document *d = cv->doc;
     guint i;
     struct draw_mark_data dd;
     gboolean expose_timescale=FALSE, expose_text=FALSE;

     /* printf("Expose: (%d,%d)+(%d,%d)\n",event->area.x,event->area.y,
	event->area.width,event->area.height); */
     chunk_view_update_image_main( cv, widget->window, event->area.x, 
				   event->area.x + event->area.width - 1 );

     if (d == NULL) return FALSE;

     /* Determine if the time scale or text/bars at the bottom needs
      * redrawing */
     if (cv->timescale) 
	  if (event->area.y+event->area.height > cv->image_height-7) {
	       expose_timescale=TRUE;
	       if (event->area.y+event->area.height > cv->image_height) {
		    expose_text = TRUE;
		    event->area.height = cv->image_height-event->area.y;
	       }
	  }

     /* Draw playback indicator */
     if ( (cv->show_bufpos) &&
	  d->playbufpos >= d->viewstart && d->playbufpos <= d->viewend ) {
	  i = calc_x( cv, d->playbufpos, widget->allocation.width );
	  if (event->area.x <= i && event->area.x+event->area.width > i) {
	       gdk_draw_line( widget->window, get_gc(BUFPOS,widget), i,
			      event->area.y, i,
			      event->area.y+event->area.height-1 );
	  }
     }
     /* Draw the marks */
     dd.view = cv;
     dd.event = event;
     document_foreach_mark( d, draw_mark, &dd );
     /* Draw the cursor */
     if ( d->cursorpos >= d->viewstart && 
	  d->cursorpos <= d->viewend ) {
	  i = calc_x( cv, d->cursorpos, widget->allocation.width );
	  if (event->area.x <= i && event->area.x+event->area.width > i) {
	       gdk_draw_line( widget->window, get_gc(CURSOR,widget), i, 
			      event->area.y, i, 
			      event->area.y+event->area.height-1 );
	  }
     }
     /* Draw the time scale */
     if (d->chunk && cv->timescale && expose_timescale) 
	  draw_timescale( cv, event, expose_text );
     return FALSE;
}


static void chunk_view_size_request(GtkWidget *widget, GtkRequisition *req)
{
     req->width = 300;
     req->height = 50;
}

static void chunk_view_size_allocate(GtkWidget *widget, GtkAllocation *all)
{
     ChunkView *cv = CHUNKVIEW(widget);
     Document *d = cv->doc;
     GTK_WIDGET_CLASS(chunk_view_parent_class)->size_allocate(widget,all);
     if (cv->image == NULL) { 	  /* Hack */
	  cv->image_width = all->width;
	  cv->image_height = all->height;
	  if (cv->timescale) cv->image_height -= font_height;
     }
     if (d == NULL) return;
     /* Call view_cache_update to make sure the view cache knows the new 
      * size. */
     view_cache_update(cv->cache,d->chunk,d->viewstart,d->viewend,
		       widget->allocation.width,NULL,NULL);
}

static off_t calc_sample(ChunkView *cv, gfloat x, gfloat xmax)
{
     return cv->doc->viewstart + (x/xmax) * 
	  (cv->doc->viewend-cv->doc->viewstart);
}

static gboolean dragmode = FALSE;
static off_t dragstart;
static off_t dragend;
static gboolean autoscroll = FALSE;
static gpointer autoscroll_source = NULL;
static ChunkView *autoscroll_view;
static gfloat autoscroll_amount;
static gint64 autoscroll_start;

static gint scroll_wheel(GtkWidget *widget, gdouble mouse_x, int direction)
{
     ChunkView *cv = CHUNKVIEW(widget);
     Document *d = cv->doc;
     gfloat zf;
     off_t ui1,ui2;
     if (d == NULL) return FALSE;
     dragstart = dragend = 
	  calc_sample( cv, mouse_x, (gfloat)widget->allocation.width);
	
     if (direction == -1)	// Scroll wheel down
     {
       if (d->viewend - d->viewstart == widget->allocation.width)
	    return FALSE;
       zf = 1.0/1.4;
     }
     else if (d->viewend - d->viewstart < 2)
	  zf = 4.0;             // Special case to avoid locking in maximum zoom
     else zf = 1.4;		// Scroll wheel up
     ui1 = dragstart-(off_t)((gfloat)(dragstart-d->viewstart))*zf;
     ui2 = dragstart+(off_t)((gfloat)(d->viewend-dragstart))*zf;
     if (ui1 < 0) ui1 = 0;
     if (ui2 < dragstart || ui2 > d->chunk->length) ui2 = d->chunk->length;
     if (ui2 == ui1) {
	  if (ui2 < d->chunk->length)
	       ui2++;
	  else if (ui1 > 0)
	       ui1--;
     }
     document_set_view(d,ui1,ui2);
     return FALSE;
}

static gint chunk_view_scrollwheel(GtkWidget *widget, GdkEventScroll *event)
{
     if (event->direction == GDK_SCROLL_DOWN) return scroll_wheel(widget, event->x, -1);
     else return scroll_wheel(widget, event->x, 1);
}

static gint chunk_view_button_press(GtkWidget *widget, GdkEventButton *event)
{     
     ChunkView *cv = CHUNKVIEW(widget);
     gdouble sp,ep;
     off_t o;
     Document *d = cv->doc;
     if (d == NULL) return FALSE;
     if (event->type == GDK_2BUTTON_PRESS && event->button == 1) {
	  o = calc_sample(cv,event->x,(gfloat)widget->allocation.width);
	  g_signal_emit(G_OBJECT(cv),
			  chunk_view_signals[DOUBLE_CLICK_SIGNAL], 0, &o);
	  return FALSE;
     }
     dragstart = dragend = 
	  calc_sample( cv, event->x, (gfloat)widget->allocation.width);

     /* Snap to sel start/end */
     sp = (gdouble)calc_x(cv,d->selstart,widget->allocation.width);
     ep = (gdouble)calc_x(cv,d->selend,widget->allocation.width);
     if (fabs(event->x - sp) < 3.0)
	  dragstart = dragend = d->selstart;
     else if (fabs(event->x - ep) < 3.0)
	  dragstart = dragend = d->selend;

     if ((event->state & GDK_SHIFT_MASK) != 0 && d->selend != d->selstart) {

	  dragmode = TRUE;
	  
	  /* The right selection endpoint is nearest to dragstart
	   * <=> dragstart > (selstart+selend)/2
	   * <=> 2*dragstart > selstart+selend
	   * <=> dragstart+dragstart > selstart+selend
	   * <=> dragstart-selend > selstart-dragstart
	   * This should be overflow-safe for large values 
	   */
	  if ((event->button == 1 && 
	       dragstart-d->selend > d->selstart-dragstart) ||
	      (event->button != 1 &&
	       dragstart-d->selend < d->selstart-dragstart) ) {
	       /* Drag right endpoint */
	       dragstart = d->selstart;
	  } else {
	       /* Drag left endpoint */
	       dragstart = d->selend;
	  }
	  document_set_selection( d, dragstart, dragend );

     } else if (event->button == 1 || event->button == 2) {
	  dragmode = TRUE;
	  if (d->selend != d->selstart) {
	       if (d->selstart >= d->viewstart && 
		   dragstart == d->selstart){
		    dragstart = d->selend;
		    dragend = d->selstart;
		    return FALSE;
	       } else if (d->selend <= d->viewend &&
			  dragstart == d->selend) {
		    dragstart = d->selstart;
		    dragend = d->selend;
		    return FALSE;
	       }
	  }
	  document_set_selection( d, dragstart, dragend );
     } else if (event->button == 3) {
	  document_set_cursor(d,dragstart);
     } else if (event->button == 4 || event->button == 5) {
	  if (event->button == 5) scroll_wheel(widget, event->x, -1);
	  else scroll_wheel(widget, event->x, 1);
     }
     return FALSE;
}

static gint chunk_view_motion_notify(GtkWidget *widget, GdkEventMotion *event)
{
     gint x1,x2;
     static GdkCursor *arrows=NULL;
     ChunkView *cv = CHUNKVIEW(widget);
     Document *d = cv->doc;
     if (d == NULL) return FALSE;
     if (dragmode) {
	  if (event->x < widget->allocation.width)
	       dragend = calc_sample ( cv, (event->x > 0.0) ? event->x : 0.0, 
				       (gfloat)widget->allocation.width );
	  else
	       dragend = d->viewend;
	  document_set_selection ( d, dragstart, dragend );
	  if (event->x < 0.0 || event->x > widget->allocation.width) {
	       if (!autoscroll) {
		    autoscroll = TRUE;
		    autoscroll_view = cv;
		    autoscroll_start = g_get_real_time();
           }
	       if (event->x < 0.0) autoscroll_amount = event->x;
	       else autoscroll_amount = event->x - widget->allocation.width;
	       chunk_view_autoscroll(NULL,autoscroll_start,NULL);
	  } else {
	       autoscroll = FALSE;
	  }
     } else if (d->selstart != d->selend) {
	  if (d->selstart >= d->viewstart) 
	       x1 = calc_x(cv,d->selstart,widget->allocation.width);
	  else
	       x1 = -500;
	  if (d->selend <= d->viewend)
	       x2 = calc_x(cv,d->selend,widget->allocation.width);
	  else
	       x2 = -500;
	  if (fabs(event->x-(double)x1)<3.0 ||
	      fabs(event->x-(double)x2)<3.0) {
	       if (arrows == NULL)
		    arrows = gdk_cursor_new(GDK_SB_H_DOUBLE_ARROW);
	       gdk_window_set_cursor(widget->window,arrows);
	  } else {
	       gdk_window_set_cursor(widget->window,NULL);
	  }
     }
     return FALSE;
}

#define FLOAT(x) ((gfloat)(x))

static int chunk_view_autoscroll(gpointer timesource, gint64 current_time,
				 gpointer user_data)
{
     gint64 diff,new_time;
     gfloat smp;
     off_t ismp;

     /* puts("chunk_view_autoscroll"); */

     g_assert(timesource == NULL || timesource == autoscroll_source);

     if (!autoscroll) return 0;
     timeval_subtract(&diff,current_time,autoscroll_start);

     /* printf("diff: %d,%d\n",diff.tv_sec,diff.tv_usec); */
     if (diff > 10000) {

	  autoscroll_start = current_time;
	  
	  /* Convert diff -> smp */
	  smp = 0.2 * FLOAT(diff/10000) * 
	       autoscroll_amount *
	       FLOAT(autoscroll_view->doc->viewend-autoscroll_view->doc->viewstart)/
	       FLOAT(GTK_WIDGET(autoscroll_view)->allocation.width);
	  /* Convert smp->ismp, update view and selection */
	  if (smp < 0.0) {
	       ismp = (off_t)(-smp);
	       if (ismp > dragend) {
		    ismp = dragend;
		    autoscroll = FALSE;
	       }
	       dragend -= ismp;
	       document_set_selection(autoscroll_view->doc,dragend,dragstart);
	       document_set_view(autoscroll_view->doc, dragend,
				 autoscroll_view->doc->viewend-ismp);
	  } else {
	       ismp = (off_t)smp;
	       if (dragend+ismp > autoscroll_view->doc->chunk->length) {
		    ismp = autoscroll_view->doc->chunk->length - dragend;
		    autoscroll = FALSE;
	       }
	       dragend += ismp;
	       document_set_selection(autoscroll_view->doc,dragstart,dragend);
	       document_set_view(autoscroll_view->doc,
				 autoscroll_view->doc->viewstart+ismp,
				 dragend);
	  }
     } 
     
     if (autoscroll) {
	  new_time = ((current_time / 25000) + 1) * 25000;
	  if (autoscroll_source == NULL)
	       autoscroll_source = 
		    mainloop_time_source_add(&new_time,chunk_view_autoscroll,
					     NULL);
	  else
	       mainloop_time_source_restart(autoscroll_source,new_time);
     }

     return 0;
}

static gint chunk_view_button_release(GtkWidget *widget, GdkEventButton *event)
{
     ChunkView *cv = CHUNKVIEW(widget);
     if (event->button == 2 && cv->doc != NULL) {
	  document_play_selection(cv->doc,FALSE,1.0);
     }
     autoscroll = FALSE;
     dragmode = FALSE;
     return FALSE;
}

static void chunk_view_class_init(ChunkViewClass *klass)
{
     GtkWidgetClass *wc = GTK_WIDGET_CLASS(klass);
     GtkObjectClass *oc = GTK_OBJECT_CLASS(klass);

     oc->destroy = chunk_view_destroy;
     wc->expose_event = chunk_view_expose;
     wc->size_request = chunk_view_size_request;
     wc->size_allocate = chunk_view_size_allocate;
     wc->button_press_event = chunk_view_button_press;
     wc->motion_notify_event = chunk_view_motion_notify;
     wc->button_release_event = chunk_view_button_release;
     wc->scroll_event = chunk_view_scrollwheel;
     klass->double_click = NULL;

     chunk_view_signals[DOUBLE_CLICK_SIGNAL] = 
         g_signal_new("double-click", G_TYPE_FROM_CLASS(klass),
                      G_SIGNAL_RUN_FIRST,
                      G_STRUCT_OFFSET(ChunkViewClass,double_click),
                      NULL, NULL, g_cclosure_marshal_VOID__POINTER,
                      G_TYPE_NONE, 1, G_TYPE_POINTER);

     gtk_object_class_add_signals(oc,chunk_view_signals,LAST_SIGNAL);
}

static void chunk_view_init(ChunkView *cv)
{
     cv->doc = NULL;
     cv->image = NULL;
     cv->timescale = TRUE;
     cv->scale_factor = 1.0;
     cv->cache = view_cache_new();
     gtk_widget_add_events( GTK_WIDGET(cv), GDK_BUTTON_MOTION_MASK |
			    GDK_BUTTON_PRESS_MASK | GDK_BUTTON_RELEASE_MASK |
			    GDK_POINTER_MOTION_MASK );
     if (!font_height) {
	  PangoLayout *pl;
	  pl = gtk_widget_create_pango_layout( GTK_WIDGET(cv), "0123456789" );
	  pango_layout_get_pixel_size(pl, (gint *)&font_width, 
				      (gint *)&font_height);
	  g_object_unref(pl);
     }
}

GtkWidget *chunk_view_new(void)
{
     return GTK_WIDGET(g_object_new(CHUNKVIEW_TYPE, NULL));
}

void chunk_view_set_document(ChunkView *cv, Document *doc)
{
     if (cv->doc == doc) return;
     if (cv->doc != NULL) {
	  g_signal_handlers_disconnect_matched(cv->doc, G_SIGNAL_MATCH_DATA,
	                                       0, 0, NULL, NULL, cv);
	  gtk_object_unref(GTK_OBJECT(cv->doc));
     }
     cv->doc = doc;
     if (doc != NULL) { 
	  gtk_object_ref(GTK_OBJECT(doc)); 
	  gtk_object_sink(GTK_OBJECT(doc)); 
	  g_signal_connect(G_OBJECT(doc),"view_changed",
			     G_CALLBACK(chunk_view_changed),cv);
	  g_signal_connect(G_OBJECT(doc),"state_changed",
			     G_CALLBACK(chunk_view_changed),cv);
	  g_signal_connect(G_OBJECT(doc),"selection_changed",
			     G_CALLBACK(chunk_view_selection_changed),cv);
	  g_signal_connect(G_OBJECT(doc),"cursor_changed",
			     G_CALLBACK(chunk_view_cursor_changed),cv);
     }
     chunk_view_changed(cv->doc,cv);
}

static void chunk_view_redraw_samples(ChunkView *cv, off_t start, off_t end)
{
     guint startpix,endpix;

     startpix = calc_x(cv,start,GTK_WIDGET(cv)->allocation.width);
     endpix = calc_x(cv,end,GTK_WIDGET(cv)->allocation.width);

     if (cv->image)
	  chunk_view_update_image(cv,startpix,endpix);

     /* printf("Calling queue_draw on: (%d,%d)+(%d,%d)\n",startpix,0,
	    1+endpix-startpix,GTK_WIDGET(cv)->allocation.height-
	    (cv->timescale?font_height:0)); */

     gtk_widget_queue_draw_area(GTK_WIDGET(cv),startpix,0,1+endpix-startpix,
				GTK_WIDGET(cv)->allocation.height-
				(cv->timescale?font_height:0));
}

void chunk_view_set_timescale(ChunkView *cv, gboolean scale_visible)
{
     if (cv->timescale == scale_visible) return;
     cv->timescale = scale_visible;
     chunk_view_changed(cv->doc,cv);
}

gboolean chunk_view_update_cache(ChunkView *view)
{
     gboolean b;
     gint i,j;     
     b = view_cache_update(view->cache, view->doc->chunk, view->doc->viewstart,
			   view->doc->viewend, view->image_width, &i, &j);

     if (!b && view->need_redraw_left != -1) {
	  gtk_widget_queue_draw_area(GTK_WIDGET(view),
				     view->need_redraw_left,
				     0,view->need_redraw_right-
				     view->need_redraw_left,
				     view->image_height);	      
	  view->need_redraw_left = -1;
     }

     if (b && i!=j) {
	  if (view->need_redraw_left == -1) {
	       view->need_redraw_left = i;
	       view->need_redraw_right = j;
	  } else {
	       if (i < view->need_redraw_left) view->need_redraw_left=i;
	       if (j > view->need_redraw_right) view->need_redraw_right=j;
	  }
	  chunk_view_update_image(view,i,j);
	  /* Repaint after 20 pixels have been updated or once per second 
	   * or we're just finished. */
	  if (view->need_redraw_right-view->need_redraw_left > 20 || 
	      (view->last_redraw_time != time(0)) ||
	      view_cache_uptodate(view->cache)) {
	       gtk_widget_queue_draw_area(GTK_WIDGET(view),
					  view->need_redraw_left,
					  0,view->need_redraw_right-
					  view->need_redraw_left,
					  view->image_height);
	       view->last_redraw_time = time(0);
	       view->need_redraw_left = -1;
	  }
     }
     return b;
}

void chunk_view_force_repaint(ChunkView *cv)
{
     chunk_view_changed(cv->doc,cv);
}

void chunk_view_set_scale(ChunkView *cv, gfloat scale)
{
     cv->scale_factor = scale;
     chunk_view_changed(cv->doc,cv);
}