cairo/src/cairo-surface-observer.c

/* cairo - a vector graphics library with display and print output
 *
 * Copyright © 2011 Intel Corporation
 *
 * This library is free software; you can redistribute it and/or
 * modify it either under the terms of the GNU Lesser General Public
 * License version 2.1 as published by the Free Software Foundation
 * (the "LGPL") or, at your option, under the terms of the Mozilla
 * Public License Version 1.1 (the "MPL"). If you do not alter this
 * notice, a recipient may use your version of this file under either
 * the MPL or the LGPL.
 *
 * You should have received a copy of the LGPL along with this library
 * in the file COPYING-LGPL-2.1; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
 * You should have received a copy of the MPL along with this library
 * in the file COPYING-MPL-1.1
 *
 * The contents of this file are subject to the Mozilla Public License
 * Version 1.1 (the "License"); you may not use this file except in
 * compliance with the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
 * OF ANY KIND, either express or implied. See the LGPL or the MPL for
 * the specific language governing rights and limitations.
 *
 * The Original Code is the cairo graphics library.
 *
 * The Initial Developer of the Original Code is Intel Corporation.
 *
 * Contributor(s):
 *      Chris Wilson <chris@chris-wilson.co.uk>
 */

#include "cairoint.h"

#include "cairo-surface-observer-private.h"

#include "cairo-array-private.h"
#include "cairo-combsort-private.h"
#include "cairo-composite-rectangles-private.h"
#include "cairo-error-private.h"
#include "cairo-image-surface-private.h"
#include "cairo-pattern-private.h"
#include "cairo-output-stream-private.h"
#include "cairo-recording-surface-private.h"
#include "cairo-script-private.h"
#include "cairo-surface-subsurface-private.h"
#include "cairo-reference-count-private.h"

static const cairo_surface_backend_t _cairo_surface_observer_backend;

/* observation/stats */

static void init_stats (struct stat *s)
{
    s->min = HUGE_VAL;
    s->max = -HUGE_VAL;
}

static void init_extents (struct extents *e)
{
    init_stats (&e->area);
}

static void init_pattern (struct pattern *p)
{
}

static void init_path (struct path *p)
{
}

static void init_clip (struct clip *c)
{
}

static void init_paint (struct paint *p)
{
    init_extents (&p->extents);
    init_pattern (&p->source);
    init_clip (&p->clip);
}

static void init_mask (struct mask *m)
{
    init_extents (&m->extents);
    init_pattern (&m->source);
    init_pattern (&m->mask);
    init_clip (&m->clip);
}

static void init_fill (struct fill *f)
{
    init_extents (&f->extents);
    init_pattern (&f->source);
    init_path (&f->path);
    init_clip (&f->clip);
}

static void init_stroke (struct stroke *s)
{
    init_extents (&s->extents);
    init_pattern (&s->source);
    init_path (&s->path);
    init_clip (&s->clip);
}

static void init_glyphs (struct glyphs *g)
{
    init_extents (&g->extents);
    init_pattern (&g->source);
    init_clip (&g->clip);
}

static cairo_status_t
log_init (cairo_observation_t *log,
	  cairo_bool_t record)
{
    memset (log, 0, sizeof(*log));

    init_paint (&log->paint);
    init_mask (&log->mask);
    init_fill (&log->fill);
    init_stroke (&log->stroke);
    init_glyphs (&log->glyphs);

    _cairo_array_init (&log->timings, sizeof (cairo_observation_record_t));

    if (record) {
	log->record = (cairo_recording_surface_t *)
	    cairo_recording_surface_create (CAIRO_CONTENT_COLOR_ALPHA, NULL);
	if (unlikely (log->record->base.status))
	    return log->record->base.status;

	log->record->optimize_clears = FALSE;
    }

    return CAIRO_STATUS_SUCCESS;
}

static void
log_fini (cairo_observation_t *log)
{
    _cairo_array_fini (&log->timings);
    cairo_surface_destroy (&log->record->base);
}

static cairo_surface_t*
get_pattern_surface (const cairo_pattern_t *pattern)
{
    return ((cairo_surface_pattern_t *)pattern)->surface;
}

static int
classify_pattern (const cairo_pattern_t *pattern,
		  const cairo_surface_t *target)
{
    int classify;

    switch (pattern->type) {
    case CAIRO_PATTERN_TYPE_SURFACE:
	if (get_pattern_surface (pattern)->type == target->type)
	    classify = 0;
	else if (get_pattern_surface (pattern)->type == CAIRO_SURFACE_TYPE_RECORDING)
	    classify = 1;
	else
	    classify = 2;
	break;
    default:
    case CAIRO_PATTERN_TYPE_SOLID:
	classify = 3;
	break;
    case CAIRO_PATTERN_TYPE_LINEAR:
	classify = 4;
	break;
    case CAIRO_PATTERN_TYPE_RADIAL:
	classify = 5;
	break;
    case CAIRO_PATTERN_TYPE_MESH:
	classify = 6;
	break;
    }
    return classify;
}

static void
add_pattern (struct pattern *stats,
	     const cairo_pattern_t *pattern,
	     const cairo_surface_t *target)
{
    stats->type[classify_pattern(pattern, target)]++;
}

static int
classify_path (const cairo_path_fixed_t *path,
	       cairo_bool_t is_fill)
{
    int classify;

    /* XXX improve for stroke */
    classify = -1;
    if (is_fill) {
	if (path->fill_is_empty)
	    classify = 0;
	else if (_cairo_path_fixed_fill_is_rectilinear (path))
	    classify = path->fill_maybe_region ? 1 : 2;
    } else {
	if (_cairo_path_fixed_stroke_is_rectilinear (path))
	    classify = 2;
    }
    if (classify == -1)
	classify = 3 + (path->has_curve_to != 0);

    return classify;
}

static void
add_path (struct path *stats,
	  const cairo_path_fixed_t *path,
	  cairo_bool_t is_fill)
{
    stats->type[classify_path(path, is_fill)]++;
}

static int
classify_clip (const cairo_clip_t *clip)
{
    int classify;

    if (clip == NULL)
	classify = 0;
    else if (_cairo_clip_is_region (clip))
	classify = 1;
    else if (clip->path == NULL)
	classify = 2;
    else if (clip->path->prev == NULL)
	classify = 3;
    else if (_cairo_clip_is_polygon (clip))
	classify = 4;
    else
	classify = 5;

    return classify;
}

static void
add_clip (struct clip *stats,
	  const cairo_clip_t *clip)
{
    stats->type[classify_clip (clip)]++;
}

static void
stats_add (struct stat *s, double v)
{
    if (v < s->min)
	s->min = v;
    if (v > s->max)
	s->max = v;
    s->sum += v;
    s->sum_sq += v*v;
    s->count++;
}

static void
add_extents (struct extents *stats,
	     const cairo_composite_rectangles_t *extents)
{
    const cairo_rectangle_int_t *r = extents->is_bounded ? &extents->bounded :&extents->unbounded;
    stats_add (&stats->area, r->width * r->height);
    stats->bounded += extents->is_bounded != 0;
    stats->unbounded += extents->is_bounded == 0;
}

/* device interface */

static void
_cairo_device_observer_lock (void *_device)
{
    cairo_device_observer_t *device = (cairo_device_observer_t *) _device;
    cairo_device_acquire (device->target);
}

static void
_cairo_device_observer_unlock (void *_device)
{
    cairo_device_observer_t *device = (cairo_device_observer_t *) _device;
    cairo_device_release (device->target);
}

static cairo_status_t
_cairo_device_observer_flush (void *_device)
{
    cairo_device_observer_t *device = (cairo_device_observer_t *) _device;

    if (device->target == NULL)
	return CAIRO_STATUS_SUCCESS;

    cairo_device_flush (device->target);
    return device->target->status;
}

static void
_cairo_device_observer_finish (void *_device)
{
    cairo_device_observer_t *device = (cairo_device_observer_t *) _device;
    log_fini (&device->log);
    cairo_device_finish (device->target);
}

static void
_cairo_device_observer_destroy (void *_device)
{
    cairo_device_observer_t *device = (cairo_device_observer_t *) _device;
    cairo_device_destroy (device->target);
    free (device);
}

static const cairo_device_backend_t _cairo_device_observer_backend = {
    CAIRO_INTERNAL_DEVICE_TYPE_OBSERVER,

    _cairo_device_observer_lock,
    _cairo_device_observer_unlock,

    _cairo_device_observer_flush,
    _cairo_device_observer_finish,
    _cairo_device_observer_destroy,
};

static cairo_device_t *
_cairo_device_create_observer_internal (cairo_device_t *target,
					cairo_bool_t record)
{
    cairo_device_observer_t *device;
    cairo_status_t status;

    device = malloc (sizeof (cairo_device_observer_t));
    if (unlikely (device == NULL))
	return _cairo_device_create_in_error (_cairo_error (CAIRO_STATUS_NO_MEMORY));

    _cairo_device_init (&device->base, &_cairo_device_observer_backend);
    status = log_init (&device->log, record);
    if (unlikely (status)) {
	free (device);
	return _cairo_device_create_in_error (status);
    }

    device->target = cairo_device_reference (target);

    return &device->base;
}

/* surface interface */

static cairo_device_observer_t *
to_device (cairo_surface_observer_t *suface)
{
    return (cairo_device_observer_t *)suface->base.device;
}

static cairo_surface_t *
_cairo_surface_create_observer_internal (cairo_device_t *device,
					 cairo_surface_t *target)
{
    cairo_surface_observer_t *surface;
    cairo_status_t status;

    surface = malloc (sizeof (cairo_surface_observer_t));
    if (unlikely (surface == NULL))
	return _cairo_surface_create_in_error (_cairo_error (CAIRO_STATUS_NO_MEMORY));

    _cairo_surface_init (&surface->base,
			 &_cairo_surface_observer_backend, device,
			 target->content);

    status = log_init (&surface->log,
		       ((cairo_device_observer_t *)device)->log.record != NULL);
    if (unlikely (status)) {
	free (surface);
	return _cairo_surface_create_in_error (status);
    }

    surface->target = cairo_surface_reference (target);
    surface->base.type = surface->target->type;
    surface->base.is_clear = surface->target->is_clear;

    cairo_list_init (&surface->paint_callbacks);
    cairo_list_init (&surface->mask_callbacks);
    cairo_list_init (&surface->fill_callbacks);
    cairo_list_init (&surface->stroke_callbacks);
    cairo_list_init (&surface->glyphs_callbacks);

    cairo_list_init (&surface->flush_callbacks);
    cairo_list_init (&surface->finish_callbacks);

    surface->log.num_surfaces++;
    to_device (surface)->log.num_surfaces++;

    return &surface->base;
}

static inline void
do_callbacks (cairo_surface_observer_t *surface, cairo_list_t *head)
{
    struct callback_list *cb;

    cairo_list_foreach_entry (cb, struct callback_list, head, link)
	cb->func (&surface->base, surface->target, cb->data);
}


static cairo_status_t
_cairo_surface_observer_finish (void *abstract_surface)
{
    cairo_surface_observer_t *surface = abstract_surface;

    do_callbacks (surface, &surface->finish_callbacks);

    cairo_surface_destroy (surface->target);
    log_fini (&surface->log);

    return CAIRO_STATUS_SUCCESS;
}

static cairo_surface_t *
_cairo_surface_observer_create_similar (void *abstract_other,
					cairo_content_t content,
					int width, int height)
{
    cairo_surface_observer_t *other = abstract_other;
    cairo_surface_t *target, *surface;

    target = NULL;
    if (other->target->backend->create_similar)
	target = other->target->backend->create_similar (other->target, content,
							 width, height);
    if (target == NULL)
	target = _cairo_image_surface_create_with_content (content,
							   width, height);

    surface = _cairo_surface_create_observer_internal (other->base.device,
						       target);
    cairo_surface_destroy (target);

    return surface;
}

static cairo_surface_t *
_cairo_surface_observer_create_similar_image (void *other,
					      cairo_format_t format,
					      int width, int height)
{
    cairo_surface_observer_t *surface = other;

    if (surface->target->backend->create_similar_image)
	return surface->target->backend->create_similar_image (surface->target,
							       format,
							       width, height);

    return NULL;
}

static cairo_surface_t *
_cairo_surface_observer_map_to_image (void *abstract_surface,
				      const cairo_rectangle_int_t *extents)
{
    cairo_surface_observer_t *surface = abstract_surface;

    if (surface->target->backend->map_to_image == NULL)
	return NULL;

    return surface->target->backend->map_to_image (surface->target, extents);
}

static cairo_int_status_t
_cairo_surface_observer_unmap_image (void *abstract_surface,
				     cairo_image_surface_t *image)
{
    cairo_surface_observer_t *surface = abstract_surface;

    if (surface->target->backend->unmap_image == NULL)
	return CAIRO_INT_STATUS_UNSUPPORTED;

    return surface->target->backend->unmap_image (surface->target, image);
}

static void
record_target (cairo_observation_record_t *r,
	       cairo_surface_t *target)
{
    cairo_rectangle_int_t extents;

    r->target_content = target->content;
    if (_cairo_surface_get_extents (target, &extents)) {
	r->target_width = extents.width;
	r->target_height = extents.height;
    } else {
	r->target_width = -1;
	r->target_height = -1;
    }
}

static cairo_observation_record_t *
record_paint (cairo_observation_record_t *r,
	      cairo_surface_t *target,
	      cairo_operator_t op,
	      const cairo_pattern_t *source,
	      const cairo_clip_t *clip,
	      cairo_time_t elapsed)
{
    record_target (r, target);

    r->op = op;
    r->source = classify_pattern (source, target);
    r->mask = -1;
    r->num_glyphs = -1;
    r->path = -1;
    r->fill_rule = -1;
    r->tolerance = -1;
    r->antialias = -1;
    r->clip = classify_clip (clip);
    r->elapsed = elapsed;

    return r;
}

static cairo_observation_record_t *
record_mask (cairo_observation_record_t *r,
	     cairo_surface_t *target,
	     cairo_operator_t op,
	     const cairo_pattern_t *source,
	     const cairo_pattern_t *mask,
	     const cairo_clip_t *clip,
	     cairo_time_t elapsed)
{
    record_target (r, target);

    r->op = op;
    r->source = classify_pattern (source, target);
    r->mask = classify_pattern (mask, target);
    r->num_glyphs = -1;
    r->path = -1;
    r->fill_rule = -1;
    r->tolerance = -1;
    r->antialias = -1;
    r->clip = classify_clip (clip);
    r->elapsed = elapsed;

    return r;
}

static cairo_observation_record_t *
record_fill (cairo_observation_record_t *r,
	     cairo_surface_t		*target,
	     cairo_operator_t		op,
	     const cairo_pattern_t	*source,
	     const cairo_path_fixed_t	*path,
	     cairo_fill_rule_t		 fill_rule,
	     double			 tolerance,
	     cairo_antialias_t		 antialias,
	     const cairo_clip_t		*clip,
	     cairo_time_t elapsed)
{
    record_target (r, target);

    r->op = op;
    r->source = classify_pattern (source, target);
    r->mask = -1;
    r->num_glyphs = -1;
    r->path = classify_path (path, TRUE);
    r->fill_rule = fill_rule;
    r->tolerance = tolerance;
    r->antialias = antialias;
    r->clip = classify_clip (clip);
    r->elapsed = elapsed;

    return r;
}

static cairo_observation_record_t *
record_stroke (cairo_observation_record_t *r,
	       cairo_surface_t		*target,
	       cairo_operator_t		op,
	       const cairo_pattern_t	*source,
	       const cairo_path_fixed_t	*path,
	       const cairo_stroke_style_t	*style,
	       const cairo_matrix_t	*ctm,
	       const cairo_matrix_t	*ctm_inverse,
	       double			 tolerance,
	       cairo_antialias_t	 antialias,
	       const cairo_clip_t	*clip,
	       cairo_time_t		 elapsed)
{
    record_target (r, target);

    r->op = op;
    r->source = classify_pattern (source, target);
    r->mask = -1;
    r->num_glyphs = -1;
    r->path = classify_path (path, FALSE);
    r->fill_rule = -1;
    r->tolerance = tolerance;
    r->antialias = antialias;
    r->clip = classify_clip (clip);
    r->elapsed = elapsed;

    return r;
}

static cairo_observation_record_t *
record_glyphs (cairo_observation_record_t *r,
	       cairo_surface_t		*target,
	       cairo_operator_t		op,
	       const cairo_pattern_t	*source,
	       cairo_glyph_t		*glyphs,
	       int			 num_glyphs,
	       cairo_scaled_font_t	*scaled_font,
	       const cairo_clip_t	*clip,
	       cairo_time_t		 elapsed)
{
    record_target (r, target);

    r->op = op;
    r->source = classify_pattern (source, target);
    r->mask = -1;
    r->path = -1;
    r->num_glyphs = num_glyphs;
    r->fill_rule = -1;
    r->tolerance = -1;
    r->antialias = -1;
    r->clip = classify_clip (clip);
    r->elapsed = elapsed;

    return r;
}

static void
add_record (cairo_observation_t *log,
	    cairo_observation_record_t *r)
{
    cairo_int_status_t status;

    r->index = log->record ? log->record->commands.num_elements : 0;

    status = _cairo_array_append (&log->timings, r);
    assert (status == CAIRO_INT_STATUS_SUCCESS);
}

static void
sync (cairo_surface_t *target, int x, int y)
{
    cairo_rectangle_int_t extents;

    extents.x = x;
    extents.y = y;
    extents.width  = 1;
    extents.height = 1;

    cairo_surface_unmap_image (target,
			       cairo_surface_map_to_image (target,
							   &extents));
}

static void
midpt (const cairo_composite_rectangles_t *extents, int *x, int *y)
{
    *x = extents->bounded.x + extents->bounded.width / 2;
    *y = extents->bounded.y + extents->bounded.height / 2;
}

static void
add_record_paint (cairo_observation_t *log,
		 cairo_surface_t *target,
		 cairo_operator_t op,
		 const cairo_pattern_t *source,
		 const cairo_clip_t *clip,
		 cairo_time_t elapsed)
{
    cairo_observation_record_t record;
    cairo_int_status_t status;

    add_record (log,
		record_paint (&record, target, op, source, clip, elapsed));

    /* We have to bypass the high-level surface layer in case it tries to be
     * too smart and discard operations; we need to record exactly what just
     * happened on the target.
     */
    if (log->record) {
	status = log->record->base.backend->paint (&log->record->base,
						   op, source, clip);
	assert (status == CAIRO_INT_STATUS_SUCCESS);
    }

    if (_cairo_time_gt (elapsed, log->paint.slowest.elapsed))
	log->paint.slowest = record;
    log->paint.elapsed = _cairo_time_add (log->paint.elapsed, elapsed);
}

static cairo_int_status_t
_cairo_surface_observer_paint (void *abstract_surface,
			       cairo_operator_t op,
			       const cairo_pattern_t *source,
			       const cairo_clip_t *clip)
{
    cairo_surface_observer_t *surface = abstract_surface;
    cairo_device_observer_t *device = to_device (surface);
    cairo_composite_rectangles_t composite;
    cairo_int_status_t status;
    cairo_time_t t;
    int x, y;

    /* XXX device locking */

    surface->log.paint.count++;
    surface->log.paint.operators[op]++;
    add_pattern (&surface->log.paint.source, source, surface->target);
    add_clip (&surface->log.paint.clip, clip);

    device->log.paint.count++;
    device->log.paint.operators[op]++;
    add_pattern (&device->log.paint.source, source, surface->target);
    add_clip (&device->log.paint.clip, clip);

    status = _cairo_composite_rectangles_init_for_paint (&composite,
							 surface->target,
							 op, source,
							 clip);
    if (unlikely (status)) {
	surface->log.paint.noop++;
	device->log.paint.noop++;
	return status;
    }

    midpt (&composite, &x, &y);

    add_extents (&surface->log.paint.extents, &composite);
    add_extents (&device->log.paint.extents, &composite);
    _cairo_composite_rectangles_fini (&composite);

    t = _cairo_time_get ();
    status = _cairo_surface_paint (surface->target,
				   op, source,
				   clip);
    if (unlikely (status))
	return status;

    sync (surface->target, x, y);
    t = _cairo_time_get_delta (t);

    add_record_paint (&surface->log, surface->target, op, source, clip, t);
    add_record_paint (&device->log, surface->target, op, source, clip, t);

    do_callbacks (surface, &surface->paint_callbacks);

    return CAIRO_STATUS_SUCCESS;
}

static void
add_record_mask (cairo_observation_t *log,
		 cairo_surface_t *target,
		 cairo_operator_t op,
		 const cairo_pattern_t *source,
		 const cairo_pattern_t *mask,
		 const cairo_clip_t *clip,
		 cairo_time_t elapsed)
{
    cairo_observation_record_t record;
    cairo_int_status_t status;

    add_record (log,
		record_mask (&record, target, op, source, mask, clip, elapsed));

    if (log->record) {
	status = log->record->base.backend->mask (&log->record->base,
						  op, source, mask, clip);
	assert (status == CAIRO_INT_STATUS_SUCCESS);
    }

    if (_cairo_time_gt (elapsed, log->mask.slowest.elapsed))
	log->mask.slowest = record;
    log->mask.elapsed = _cairo_time_add (log->mask.elapsed, elapsed);
}

static cairo_int_status_t
_cairo_surface_observer_mask (void *abstract_surface,
			      cairo_operator_t op,
			      const cairo_pattern_t *source,
			      const cairo_pattern_t *mask,
			      const cairo_clip_t *clip)
{
    cairo_surface_observer_t *surface = abstract_surface;
    cairo_device_observer_t *device = to_device (surface);
    cairo_composite_rectangles_t composite;
    cairo_int_status_t status;
    cairo_time_t t;
    int x, y;

    surface->log.mask.count++;
    surface->log.mask.operators[op]++;
    add_pattern (&surface->log.mask.source, source, surface->target);
    add_pattern (&surface->log.mask.mask, mask, surface->target);
    add_clip (&surface->log.mask.clip, clip);

    device->log.mask.count++;
    device->log.mask.operators[op]++;
    add_pattern (&device->log.mask.source, source, surface->target);
    add_pattern (&device->log.mask.mask, mask, surface->target);
    add_clip (&device->log.mask.clip, clip);

    status = _cairo_composite_rectangles_init_for_mask (&composite,
							surface->target,
							op, source, mask,
							clip);
    if (unlikely (status)) {
	surface->log.mask.noop++;
	device->log.mask.noop++;
	return status;
    }

    midpt (&composite, &x, &y);

    add_extents (&surface->log.mask.extents, &composite);
    add_extents (&device->log.mask.extents, &composite);
    _cairo_composite_rectangles_fini (&composite);

    t = _cairo_time_get ();
    status =  _cairo_surface_mask (surface->target,
				   op, source, mask,
				   clip);
    if (unlikely (status))
	return status;

    sync (surface->target, x, y);
    t = _cairo_time_get_delta (t);

    add_record_mask (&surface->log,
		     surface->target, op, source, mask, clip,
		     t);
    add_record_mask (&device->log,
		     surface->target, op, source, mask, clip,
		     t);

    do_callbacks (surface, &surface->mask_callbacks);

    return CAIRO_STATUS_SUCCESS;
}

static void
add_record_fill (cairo_observation_t *log,
		 cairo_surface_t *target,
		 cairo_operator_t		op,
		 const cairo_pattern_t		*source,
		 const cairo_path_fixed_t	*path,
		 cairo_fill_rule_t		 fill_rule,
		 double				 tolerance,
		 cairo_antialias_t		 antialias,
		 const cairo_clip_t		 *clip,
		 cairo_time_t elapsed)
{
    cairo_observation_record_t record;
    cairo_int_status_t status;

    add_record (log,
		record_fill (&record,
			     target, op, source,
			     path, fill_rule, tolerance, antialias,
			     clip, elapsed));

    if (log->record) {
	status = log->record->base.backend->fill (&log->record->base,
						  op, source,
						  path, fill_rule,
						  tolerance, antialias,
						  clip);
	assert (status == CAIRO_INT_STATUS_SUCCESS);
    }

    if (_cairo_time_gt (elapsed, log->fill.slowest.elapsed))
	log->fill.slowest = record;
    log->fill.elapsed = _cairo_time_add (log->fill.elapsed, elapsed);
}

static cairo_int_status_t
_cairo_surface_observer_fill (void			*abstract_surface,
			      cairo_operator_t		op,
			      const cairo_pattern_t	*source,
			      const cairo_path_fixed_t	*path,
			      cairo_fill_rule_t		fill_rule,
			      double			 tolerance,
			      cairo_antialias_t		antialias,
			      const cairo_clip_t	*clip)
{
    cairo_surface_observer_t *surface = abstract_surface;
    cairo_device_observer_t *device = to_device (surface);
    cairo_composite_rectangles_t composite;
    cairo_int_status_t status;
    cairo_time_t t;
    int x, y;

    surface->log.fill.count++;
    surface->log.fill.operators[op]++;
    surface->log.fill.fill_rule[fill_rule]++;
    surface->log.fill.antialias[antialias]++;
    add_pattern (&surface->log.fill.source, source, surface->target);
    add_path (&surface->log.fill.path, path, TRUE);
    add_clip (&surface->log.fill.clip, clip);

    device->log.fill.count++;
    device->log.fill.operators[op]++;
    device->log.fill.fill_rule[fill_rule]++;
    device->log.fill.antialias[antialias]++;
    add_pattern (&device->log.fill.source, source, surface->target);
    add_path (&device->log.fill.path, path, TRUE);
    add_clip (&device->log.fill.clip, clip);

    status = _cairo_composite_rectangles_init_for_fill (&composite,
							surface->target,
							op, source, path,
							clip);
    if (unlikely (status)) {
	surface->log.fill.noop++;
	device->log.fill.noop++;
	return status;
    }

    midpt (&composite, &x, &y);

    add_extents (&surface->log.fill.extents, &composite);
    add_extents (&device->log.fill.extents, &composite);
    _cairo_composite_rectangles_fini (&composite);

    t = _cairo_time_get ();
    status = _cairo_surface_fill (surface->target,
				  op, source, path,
				  fill_rule, tolerance, antialias,
				  clip);
    if (unlikely (status))
	return status;

    sync (surface->target, x, y);
    t = _cairo_time_get_delta (t);

    add_record_fill (&surface->log,
		     surface->target, op, source, path,
		     fill_rule, tolerance, antialias,
		     clip, t);

    add_record_fill (&device->log,
		     surface->target, op, source, path,
		     fill_rule, tolerance, antialias,
		     clip, t);

    do_callbacks (surface, &surface->fill_callbacks);

    return CAIRO_STATUS_SUCCESS;
}

static void
add_record_stroke (cairo_observation_t *log,
		 cairo_surface_t *target,
		 cairo_operator_t		 op,
		 const cairo_pattern_t		*source,
		 const cairo_path_fixed_t	*path,
		 const cairo_stroke_style_t	*style,
		 const cairo_matrix_t		*ctm,
		 const cairo_matrix_t		*ctm_inverse,
		 double				 tolerance,
		 cairo_antialias_t		 antialias,
		 const cairo_clip_t		*clip,
		 cairo_time_t elapsed)
{
    cairo_observation_record_t record;
    cairo_int_status_t status;

    add_record (log,
		record_stroke (&record,
			       target, op, source,
			       path, style, ctm,ctm_inverse,
			       tolerance, antialias,
			       clip, elapsed));

    if (log->record) {
	status = log->record->base.backend->stroke (&log->record->base,
						    op, source,
						    path, style, ctm,ctm_inverse,
						    tolerance, antialias,
						    clip);
	assert (status == CAIRO_INT_STATUS_SUCCESS);
    }

    if (_cairo_time_gt (elapsed, log->stroke.slowest.elapsed))
	log->stroke.slowest = record;
    log->stroke.elapsed = _cairo_time_add (log->stroke.elapsed, elapsed);
}

static cairo_int_status_t
_cairo_surface_observer_stroke (void				*abstract_surface,
				cairo_operator_t		 op,
				const cairo_pattern_t		*source,
				const cairo_path_fixed_t	*path,
				const cairo_stroke_style_t	*style,
				const cairo_matrix_t		*ctm,
				const cairo_matrix_t		*ctm_inverse,
				double				 tolerance,
				cairo_antialias_t		 antialias,
				const cairo_clip_t		*clip)
{
    cairo_surface_observer_t *surface = abstract_surface;
    cairo_device_observer_t *device = to_device (surface);
    cairo_composite_rectangles_t composite;
    cairo_int_status_t status;
    cairo_time_t t;
    int x, y;

    surface->log.stroke.count++;
    surface->log.stroke.operators[op]++;
    surface->log.stroke.antialias[antialias]++;
    surface->log.stroke.caps[style->line_cap]++;
    surface->log.stroke.joins[style->line_join]++;
    add_pattern (&surface->log.stroke.source, source, surface->target);
    add_path (&surface->log.stroke.path, path, FALSE);
    add_clip (&surface->log.stroke.clip, clip);

    device->log.stroke.count++;
    device->log.stroke.operators[op]++;
    device->log.stroke.antialias[antialias]++;
    device->log.stroke.caps[style->line_cap]++;
    device->log.stroke.joins[style->line_join]++;
    add_pattern (&device->log.stroke.source, source, surface->target);
    add_path (&device->log.stroke.path, path, FALSE);
    add_clip (&device->log.stroke.clip, clip);

    status = _cairo_composite_rectangles_init_for_stroke (&composite,
							  surface->target,
							  op, source,
							  path, style, ctm,
							  clip);
    if (unlikely (status)) {
	surface->log.stroke.noop++;
	device->log.stroke.noop++;
	return status;
    }

    midpt (&composite, &x, &y);

    add_extents (&surface->log.stroke.extents, &composite);
    add_extents (&device->log.stroke.extents, &composite);
    _cairo_composite_rectangles_fini (&composite);

    t = _cairo_time_get ();
    status = _cairo_surface_stroke (surface->target,
				  op, source, path,
				  style, ctm, ctm_inverse,
				  tolerance, antialias,
				  clip);
    if (unlikely (status))
	return status;

    sync (surface->target, x, y);
    t = _cairo_time_get_delta (t);

    add_record_stroke (&surface->log,
		       surface->target, op, source, path,
		       style, ctm,ctm_inverse,
		       tolerance, antialias,
		       clip, t);

    add_record_stroke (&device->log,
		       surface->target, op, source, path,
		       style, ctm,ctm_inverse,
		       tolerance, antialias,
		       clip, t);

    do_callbacks (surface, &surface->stroke_callbacks);

    return CAIRO_STATUS_SUCCESS;
}

static void
add_record_glyphs (cairo_observation_t	*log,
		   cairo_surface_t	*target,
		   cairo_operator_t	 op,
		   const cairo_pattern_t*source,
		   cairo_glyph_t	*glyphs,
		   int			 num_glyphs,
		   cairo_scaled_font_t	*scaled_font,
		   const cairo_clip_t	*clip,
		   cairo_time_t elapsed)
{
    cairo_observation_record_t record;
    cairo_int_status_t status;

    add_record (log,
		record_glyphs (&record,
			       target, op, source,
			       glyphs, num_glyphs, scaled_font,
			       clip, elapsed));

    if (log->record) {
	status = log->record->base.backend->show_text_glyphs (&log->record->base,
							      op, source,
							      NULL, 0,
							      glyphs, num_glyphs,
							      NULL, 0, 0,
							      scaled_font,
							      clip);
	assert (status == CAIRO_INT_STATUS_SUCCESS);
    }

    if (_cairo_time_gt (elapsed, log->glyphs.slowest.elapsed))
	log->glyphs.slowest = record;
    log->glyphs.elapsed = _cairo_time_add (log->glyphs.elapsed, elapsed);
}

static cairo_int_status_t
_cairo_surface_observer_glyphs (void			*abstract_surface,
				cairo_operator_t	 op,
				const cairo_pattern_t	*source,
				cairo_glyph_t		*glyphs,
				int			 num_glyphs,
				cairo_scaled_font_t	*scaled_font,
				const cairo_clip_t		*clip)
{
    cairo_surface_observer_t *surface = abstract_surface;
    cairo_device_observer_t *device = to_device (surface);
    cairo_composite_rectangles_t composite;
    cairo_int_status_t status;
    cairo_glyph_t *dev_glyphs;
    cairo_time_t t;
    int x, y;

    surface->log.glyphs.count++;
    surface->log.glyphs.operators[op]++;
    add_pattern (&surface->log.glyphs.source, source, surface->target);
    add_clip (&surface->log.glyphs.clip, clip);

    device->log.glyphs.count++;
    device->log.glyphs.operators[op]++;
    add_pattern (&device->log.glyphs.source, source, surface->target);
    add_clip (&device->log.glyphs.clip, clip);

    status = _cairo_composite_rectangles_init_for_glyphs (&composite,
							  surface->target,
							  op, source,
							  scaled_font,
							  glyphs, num_glyphs,
							  clip,
							  NULL);
    if (unlikely (status)) {
	surface->log.glyphs.noop++;
	device->log.glyphs.noop++;
	return status;
    }

    midpt (&composite, &x, &y);

    add_extents (&surface->log.glyphs.extents, &composite);
    add_extents (&device->log.glyphs.extents, &composite);
    _cairo_composite_rectangles_fini (&composite);

    /* XXX We have to copy the glyphs, because the backend is allowed to
     * modify! */
    dev_glyphs = _cairo_malloc_ab (num_glyphs, sizeof (cairo_glyph_t));
    if (unlikely (dev_glyphs == NULL))
	return _cairo_error (CAIRO_STATUS_NO_MEMORY);
    memcpy (dev_glyphs, glyphs, num_glyphs * sizeof (cairo_glyph_t));

    t = _cairo_time_get ();
    status = _cairo_surface_show_text_glyphs (surface->target, op, source,
					      NULL, 0,
					      dev_glyphs, num_glyphs,
					      NULL, 0, 0,
					      scaled_font,
					      clip);
    free (dev_glyphs);
    if (unlikely (status))
	return status;

    sync (surface->target, x, y);
    t = _cairo_time_get_delta (t);

    add_record_glyphs (&surface->log,
		       surface->target, op, source,
		       glyphs, num_glyphs, scaled_font,
		       clip, t);

    add_record_glyphs (&device->log,
		       surface->target, op, source,
		       glyphs, num_glyphs, scaled_font,
		       clip, t);

    do_callbacks (surface, &surface->glyphs_callbacks);

    return CAIRO_STATUS_SUCCESS;
}

static cairo_status_t
_cairo_surface_observer_flush (void *abstract_surface)
{
    cairo_surface_observer_t *surface = abstract_surface;

    do_callbacks (surface, &surface->flush_callbacks);

    cairo_surface_flush (surface->target);
    return surface->target->status;
}

static cairo_status_t
_cairo_surface_observer_mark_dirty (void *abstract_surface,
				      int x, int y,
				      int width, int height)
{
    cairo_surface_observer_t *surface = abstract_surface;
    cairo_status_t status;

    printf ("mark-dirty (%d, %d) x (%d, %d)\n", x, y, width, height);

    status = CAIRO_STATUS_SUCCESS;
    if (surface->target->backend->mark_dirty_rectangle)
	status = surface->target->backend->mark_dirty_rectangle (surface->target,
						       x,y, width,height);

    return status;
}

static cairo_int_status_t
_cairo_surface_observer_copy_page (void *abstract_surface)
{
    cairo_surface_observer_t *surface = abstract_surface;
    cairo_status_t status;

    status = CAIRO_STATUS_SUCCESS;
    if (surface->target->backend->copy_page)
	status = surface->target->backend->copy_page (surface->target);

    return status;
}

static cairo_int_status_t
_cairo_surface_observer_show_page (void *abstract_surface)
{
    cairo_surface_observer_t *surface = abstract_surface;
    cairo_status_t status;

    status = CAIRO_STATUS_SUCCESS;
    if (surface->target->backend->show_page)
	status = surface->target->backend->show_page (surface->target);

    return status;
}

static cairo_bool_t
_cairo_surface_observer_get_extents (void *abstract_surface,
				     cairo_rectangle_int_t *extents)
{
    cairo_surface_observer_t *surface = abstract_surface;
    return _cairo_surface_get_extents (surface->target, extents);
}

static void
_cairo_surface_observer_get_font_options (void *abstract_surface,
					  cairo_font_options_t *options)
{
    cairo_surface_observer_t *surface = abstract_surface;

    if (surface->target->backend->get_font_options != NULL)
	surface->target->backend->get_font_options (surface->target, options);
}

static cairo_status_t
_cairo_surface_observer_acquire_source_image (void                    *abstract_surface,
						cairo_image_surface_t  **image_out,
						void                   **image_extra)
{
    cairo_surface_observer_t *surface = abstract_surface;

    surface->log.num_sources_acquired++;
    to_device (surface)->log.num_sources_acquired++;

    return _cairo_surface_acquire_source_image (surface->target,
						image_out, image_extra);
}

static void
_cairo_surface_observer_release_source_image (void                   *abstract_surface,
						cairo_image_surface_t  *image,
						void                   *image_extra)
{
    cairo_surface_observer_t *surface = abstract_surface;

    _cairo_surface_release_source_image (surface->target, image, image_extra);
}

static cairo_surface_t *
_cairo_surface_observer_snapshot (void *abstract_surface)
{
    cairo_surface_observer_t *surface = abstract_surface;

    /* XXX hook onto the snapshot so that we measure number of reads */

    if (surface->target->backend->snapshot)
	return surface->target->backend->snapshot (surface->target);

    return NULL;
}

static cairo_t *
_cairo_surface_observer_create_context(void *target)
{
    cairo_surface_observer_t *surface = target;

    if (_cairo_surface_is_subsurface (&surface->base))
	surface = (cairo_surface_observer_t *)
	    _cairo_surface_subsurface_get_target (&surface->base);

    surface->log.num_contexts++;
    to_device (surface)->log.num_contexts++;

    return surface->target->backend->create_context (target);
}

static const cairo_surface_backend_t _cairo_surface_observer_backend = {
    CAIRO_INTERNAL_SURFACE_TYPE_OBSERVER,
    _cairo_surface_observer_finish,

    _cairo_surface_observer_create_context,

    _cairo_surface_observer_create_similar,
    _cairo_surface_observer_create_similar_image,
    _cairo_surface_observer_map_to_image,
    _cairo_surface_observer_unmap_image,

    _cairo_surface_observer_acquire_source_image,
    _cairo_surface_observer_release_source_image,
    _cairo_surface_observer_snapshot,

    _cairo_surface_observer_copy_page,
    _cairo_surface_observer_show_page,

    _cairo_surface_observer_get_extents,
    _cairo_surface_observer_get_font_options,

    _cairo_surface_observer_flush,
    _cairo_surface_observer_mark_dirty,

    _cairo_surface_observer_paint,
    _cairo_surface_observer_mask,
    _cairo_surface_observer_stroke,
    _cairo_surface_observer_fill,
    NULL, /* fill-stroke */
    _cairo_surface_observer_glyphs,
};

/**
 * cairo_surface_create_observer:
 * @target: an existing surface for which the observer will watch
 *
 * Create a new surface that exists solely to watch another is doing. In
 * the process it will log operations and times, which are fast, which are
 * slow, which are frequent, etc.
 *
 * Return value: a pointer to the newly allocated surface. The caller
 * owns the surface and should call cairo_surface_destroy() when done
 * with it.
 *
 * This function always returns a valid pointer, but it will return a
 * pointer to a "nil" surface if @other is already in an error state
 * or any other error occurs.
 *
 * Since: 1.12
 **/
cairo_surface_t *
cairo_surface_create_observer (cairo_surface_t *target,
			       cairo_surface_observer_mode_t mode)
{
    cairo_device_t *device;
    cairo_surface_t *surface;
    cairo_bool_t record;

    if (unlikely (target->status))
	return _cairo_surface_create_in_error (target->status);
    if (unlikely (target->finished))
	return _cairo_surface_create_in_error (_cairo_error (CAIRO_STATUS_SURFACE_FINISHED));

    record = mode & CAIRO_SURFACE_OBSERVER_RECORD_OPERATIONS;
    device = _cairo_device_create_observer_internal (target->device, record);
    if (unlikely (device->status))
	return _cairo_surface_create_in_error (device->status);

    surface = _cairo_surface_create_observer_internal (device, target);
    cairo_device_destroy (device);

    return surface;
}

static cairo_status_t
_cairo_surface_observer_add_callback (cairo_list_t *head,
				      cairo_surface_observer_callback_t func,
				      void *data)
{
    struct callback_list *cb;

    cb = malloc (sizeof (*cb));
    if (unlikely (cb == NULL))
	return _cairo_error (CAIRO_STATUS_NO_MEMORY);

    cairo_list_add (&cb->link, head);
    cb->func = func;
    cb->data = data;

    return CAIRO_STATUS_SUCCESS;
}

cairo_status_t
cairo_surface_observer_add_paint_callback (cairo_surface_t *abstract_surface,
					    cairo_surface_observer_callback_t func,
					    void *data)
{
    cairo_surface_observer_t *surface;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_surface->ref_count)))
	return abstract_surface->status;

    if (! _cairo_surface_is_observer (abstract_surface))
	return _cairo_error (CAIRO_STATUS_SURFACE_TYPE_MISMATCH);

    surface = (cairo_surface_observer_t *)abstract_surface;
    return _cairo_surface_observer_add_callback (&surface->paint_callbacks,
						 func, data);
}

cairo_status_t
cairo_surface_observer_add_mask_callback (cairo_surface_t *abstract_surface,
					  cairo_surface_observer_callback_t func,
					  void *data)
{
    cairo_surface_observer_t *surface;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_surface->ref_count)))
	return abstract_surface->status;

    if (! _cairo_surface_is_observer (abstract_surface))
	return _cairo_error (CAIRO_STATUS_SURFACE_TYPE_MISMATCH);

    surface = (cairo_surface_observer_t *)abstract_surface;
    return _cairo_surface_observer_add_callback (&surface->mask_callbacks,
						 func, data);
}

cairo_status_t
cairo_surface_observer_add_fill_callback (cairo_surface_t *abstract_surface,
					  cairo_surface_observer_callback_t func,
					  void *data)
{
    cairo_surface_observer_t *surface;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_surface->ref_count)))
	return abstract_surface->status;

    if (! _cairo_surface_is_observer (abstract_surface))
	return _cairo_error (CAIRO_STATUS_SURFACE_TYPE_MISMATCH);

    surface = (cairo_surface_observer_t *)abstract_surface;
    return _cairo_surface_observer_add_callback (&surface->fill_callbacks,
						 func, data);
}

cairo_status_t
cairo_surface_observer_add_stroke_callback (cairo_surface_t *abstract_surface,
					    cairo_surface_observer_callback_t func,
					    void *data)
{
    cairo_surface_observer_t *surface;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_surface->ref_count)))
	return abstract_surface->status;

    if (! _cairo_surface_is_observer (abstract_surface))
	return _cairo_error (CAIRO_STATUS_SURFACE_TYPE_MISMATCH);

    surface = (cairo_surface_observer_t *)abstract_surface;
    return _cairo_surface_observer_add_callback (&surface->stroke_callbacks,
						 func, data);
}

cairo_status_t
cairo_surface_observer_add_glyphs_callback (cairo_surface_t *abstract_surface,
					    cairo_surface_observer_callback_t func,
					    void *data)
{
    cairo_surface_observer_t *surface;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_surface->ref_count)))
	return abstract_surface->status;

    if (! _cairo_surface_is_observer (abstract_surface))
	return _cairo_error (CAIRO_STATUS_SURFACE_TYPE_MISMATCH);

    surface = (cairo_surface_observer_t *)abstract_surface;
    return _cairo_surface_observer_add_callback (&surface->glyphs_callbacks,
						 func, data);
}

cairo_status_t
cairo_surface_observer_add_flush_callback (cairo_surface_t *abstract_surface,
					   cairo_surface_observer_callback_t func,
					   void *data)
{
    cairo_surface_observer_t *surface;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_surface->ref_count)))
	return abstract_surface->status;

    if (! _cairo_surface_is_observer (abstract_surface))
	return _cairo_error (CAIRO_STATUS_SURFACE_TYPE_MISMATCH);

    surface = (cairo_surface_observer_t *)abstract_surface;
    return _cairo_surface_observer_add_callback (&surface->flush_callbacks,
						 func, data);
}

cairo_status_t
cairo_surface_observer_add_finish_callback (cairo_surface_t *abstract_surface,
					    cairo_surface_observer_callback_t func,
					    void *data)
{
    cairo_surface_observer_t *surface;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_surface->ref_count)))
	return abstract_surface->status;

    if (! _cairo_surface_is_observer (abstract_surface))
	return _cairo_error (CAIRO_STATUS_SURFACE_TYPE_MISMATCH);

    surface = (cairo_surface_observer_t *)abstract_surface;
    return _cairo_surface_observer_add_callback (&surface->finish_callbacks,
						 func, data);
}

static void
print_extents (cairo_output_stream_t *stream, const struct extents *e)
{
    _cairo_output_stream_printf (stream,
				 "  extents: total %g, avg %g [unbounded %d]\n",
				 e->area.sum,
				 e->area.sum / e->area.count,
				 e->unbounded);
}

static inline int ordercmp (int a, int b, const unsigned int *array)
{
    /* high to low */
    return array[b] - array[a];
}
CAIRO_COMBSORT_DECLARE_WITH_DATA (sort_order, int, ordercmp)

static void
print_array (cairo_output_stream_t *stream,
	     const unsigned int *array,
	     const char **names,
	     int count)
{
    int order[64];
    int i, j;

    assert (count < ARRAY_LENGTH (order));
    for (i = j = 0; i < count; i++) {
	if (array[i] != 0)
	    order[j++] = i;
    }

    sort_order (order, j, (void *)array);
    for (i = 0; i < j; i++)
	_cairo_output_stream_printf (stream, " %d %s%s",
				     array[order[i]], names[order[i]],
				     i < j -1 ? "," : "");
}

static const char *operator_names[] = {
    "CLEAR",	/* CAIRO_OPERATOR_CLEAR */

    "SOURCE",	/* CAIRO_OPERATOR_SOURCE */
    "OVER",		/* CAIRO_OPERATOR_OVER */
    "IN",		/* CAIRO_OPERATOR_IN */
    "OUT",		/* CAIRO_OPERATOR_OUT */
    "ATOP",		/* CAIRO_OPERATOR_ATOP */

    "DEST",		/* CAIRO_OPERATOR_DEST */
    "DEST_OVER",	/* CAIRO_OPERATOR_DEST_OVER */
    "DEST_IN",	/* CAIRO_OPERATOR_DEST_IN */
    "DEST_OUT",	/* CAIRO_OPERATOR_DEST_OUT */
    "DEST_ATOP",	/* CAIRO_OPERATOR_DEST_ATOP */

    "XOR",		/* CAIRO_OPERATOR_XOR */
    "ADD",		/* CAIRO_OPERATOR_ADD */
    "SATURATE",	/* CAIRO_OPERATOR_SATURATE */

    "MULTIPLY",	/* CAIRO_OPERATOR_MULTIPLY */
    "SCREEN",	/* CAIRO_OPERATOR_SCREEN */
    "OVERLAY",	/* CAIRO_OPERATOR_OVERLAY */
    "DARKEN",	/* CAIRO_OPERATOR_DARKEN */
    "LIGHTEN",	/* CAIRO_OPERATOR_LIGHTEN */
    "DODGE",	/* CAIRO_OPERATOR_COLOR_DODGE */
    "BURN",		/* CAIRO_OPERATOR_COLOR_BURN */
    "HARD_LIGHT",	/* CAIRO_OPERATOR_HARD_LIGHT */
    "SOFT_LIGHT",	/* CAIRO_OPERATOR_SOFT_LIGHT */
    "DIFFERENCE",	/* CAIRO_OPERATOR_DIFFERENCE */
    "EXCLUSION",	/* CAIRO_OPERATOR_EXCLUSION */
    "HSL_HUE",	/* CAIRO_OPERATOR_HSL_HUE */
    "HSL_SATURATION", /* CAIRO_OPERATOR_HSL_SATURATION */
    "HSL_COLOR",	/* CAIRO_OPERATOR_HSL_COLOR */
    "HSL_LUMINOSITY" /* CAIRO_OPERATOR_HSL_LUMINOSITY */
};
static void
print_operators (cairo_output_stream_t *stream, unsigned int *array)
{
    _cairo_output_stream_printf (stream, "  op:");
    print_array (stream, array, operator_names, NUM_OPERATORS);
    _cairo_output_stream_printf (stream, "\n");
}

static const char *fill_rule_names[] = {
    "non-zero",
    "even-odd",
};
static void
print_fill_rule (cairo_output_stream_t *stream, unsigned int *array)
{
    _cairo_output_stream_printf (stream, "  fill rule:");
    print_array (stream, array, fill_rule_names, ARRAY_LENGTH(fill_rule_names));
    _cairo_output_stream_printf (stream, "\n");
}

static const char *cap_names[] = {
    "butt",		/* CAIRO_LINE_CAP_BUTT */
    "round",	/* CAIRO_LINE_CAP_ROUND */
    "square"	/* CAIRO_LINE_CAP_SQUARE */
};
static void
print_line_caps (cairo_output_stream_t *stream, unsigned int *array)
{
    _cairo_output_stream_printf (stream, "  caps:");
    print_array (stream, array, cap_names, NUM_CAPS);
    _cairo_output_stream_printf (stream, "\n");
}

static const char *join_names[] = {
    "miter",	/* CAIRO_LINE_JOIN_MITER */
    "round",	/* CAIRO_LINE_JOIN_ROUND */
    "bevel",	/* CAIRO_LINE_JOIN_BEVEL */
};
static void
print_line_joins (cairo_output_stream_t *stream, unsigned int *array)
{
    _cairo_output_stream_printf (stream, "  joins:");
    print_array (stream, array, join_names, NUM_JOINS);
    _cairo_output_stream_printf (stream, "\n");
}

static const char *antialias_names[] = {
    "default",
    "none",
    "gray",
    "subpixel",
    "fast",
    "good",
    "best"
};
static void
print_antialias (cairo_output_stream_t *stream, unsigned int *array)
{
    _cairo_output_stream_printf (stream, "  antialias:");
    print_array (stream, array, antialias_names, NUM_ANTIALIAS);
    _cairo_output_stream_printf (stream, "\n");
}

static const char *pattern_names[] = {
    "native",
    "record",
    "other surface",
    "solid",
    "linear",
    "radial",
    "mesh"
};
static void
print_pattern (cairo_output_stream_t *stream,
	       const char *name,
	       const struct pattern *p)
{
    _cairo_output_stream_printf (stream, "  %s:", name);
    print_array (stream, p->type, pattern_names, ARRAY_LENGTH (pattern_names));
    _cairo_output_stream_printf (stream, "\n");
}

static const char *path_names[] = {
    "empty",
    "pixel-aligned",
    "rectliinear",
    "straight",
    "curved",
};
static void
print_path (cairo_output_stream_t *stream,
	    const struct path *p)
{
    _cairo_output_stream_printf (stream, "  path:");
    print_array (stream, p->type, path_names, ARRAY_LENGTH (path_names));
    _cairo_output_stream_printf (stream, "\n");
}

static const char *clip_names[] = {
    "none",
    "region",
    "boxes",
    "single path",
    "polygon",
    "general",
};
static void
print_clip (cairo_output_stream_t *stream, const struct clip *c)
{
    _cairo_output_stream_printf (stream, "  clip:");
    print_array (stream, c->type, clip_names, ARRAY_LENGTH (clip_names));
    _cairo_output_stream_printf (stream, "\n");
}

static void
print_record (cairo_output_stream_t *stream,
	      cairo_observation_record_t *r)
{
    _cairo_output_stream_printf (stream, "  op: %s\n", operator_names[r->op]);
    _cairo_output_stream_printf (stream, "  source: %s\n",
				 pattern_names[r->source]);
    if (r->mask != -1)
	_cairo_output_stream_printf (stream, "  mask: %s\n",
				     pattern_names[r->mask]);
    if (r->num_glyphs != -1)
	_cairo_output_stream_printf (stream, "  num_glyphs: %d\n",
				     r->num_glyphs);
    if (r->path != -1)
	_cairo_output_stream_printf (stream, "  path: %s\n",
				    path_names[r->path]);
    if (r->fill_rule != -1)
	_cairo_output_stream_printf (stream, "  fill rule: %s\n",
				     fill_rule_names[r->fill_rule]);
    if (r->antialias != -1)
	_cairo_output_stream_printf (stream, "  antialias: %s\n",
				     antialias_names[r->antialias]);
    _cairo_output_stream_printf (stream, "  clip: %s\n", clip_names[r->clip]);
    _cairo_output_stream_printf (stream, "  elapsed: %f ns\n",
				 _cairo_time_to_ns (r->elapsed));
}

static double percent (cairo_time_t a, cairo_time_t b)
{
    /* Fake %.1f */
    return _cairo_round (_cairo_time_to_s (a) * 1000 /
			 _cairo_time_to_s (b)) / 10;
}

static cairo_bool_t
replay_record (cairo_observation_t *log,
	       cairo_observation_record_t *r,
	       cairo_device_t *script)
{
    cairo_surface_t *surface;
    cairo_int_status_t status;

    if (log->record == NULL)
	return FALSE;

    surface = cairo_script_surface_create (script,
					   r->target_content,
					   r->target_width,
					   r->target_height);
    status =
	_cairo_recording_surface_replay_one (log->record, r->index, surface);
    cairo_surface_destroy (surface);

    assert (status == CAIRO_INT_STATUS_SUCCESS);

    return TRUE;
}

static cairo_time_t
_cairo_observation_total_elapsed (cairo_observation_t *log)
{
    cairo_time_t total;

    total = log->paint.elapsed;
    total = _cairo_time_add (total, log->mask.elapsed);
    total = _cairo_time_add (total, log->fill.elapsed);
    total = _cairo_time_add (total, log->stroke.elapsed);
    total = _cairo_time_add (total, log->glyphs.elapsed);

    return total;
}

static void
_cairo_observation_print (cairo_output_stream_t *stream,
			  cairo_observation_t *log)
{
    cairo_device_t *script;
    cairo_time_t total;

    script = _cairo_script_context_create_internal (stream);
    _cairo_script_context_attach_snapshots (script, FALSE);

    total = _cairo_observation_total_elapsed (log);

    _cairo_output_stream_printf (stream, "elapsed: %f\n",
				 _cairo_time_to_ns (total));
    _cairo_output_stream_printf (stream, "surfaces: %d\n",
				 log->num_surfaces);
    _cairo_output_stream_printf (stream, "contexts: %d\n",
				 log->num_contexts);
    _cairo_output_stream_printf (stream, "sources acquired: %d\n",
				 log->num_sources_acquired);


    _cairo_output_stream_printf (stream, "paint: count %d [no-op %d], elapsed %f [%f%%]\n",
				 log->paint.count, log->paint.noop,
				 _cairo_time_to_ns (log->paint.elapsed),
				 percent (log->paint.elapsed, total));
    if (log->paint.count) {
	print_extents (stream, &log->paint.extents);
	print_operators (stream, log->paint.operators);
	print_pattern (stream, "source", &log->paint.source);
	print_clip (stream, &log->paint.clip);

	_cairo_output_stream_printf (stream, "slowest paint: %f%%\n",
				     percent (log->paint.slowest.elapsed,
					      log->paint.elapsed));
	print_record (stream, &log->paint.slowest);

	_cairo_output_stream_printf (stream, "\n");
	if (replay_record (log, &log->paint.slowest, script))
	    _cairo_output_stream_printf (stream, "\n\n");
    }

    _cairo_output_stream_printf (stream, "mask: count %d [no-op %d], elapsed %f [%f%%]\n",
				 log->mask.count, log->mask.noop,
				 _cairo_time_to_ns (log->mask.elapsed),
				 percent (log->mask.elapsed, total));
    if (log->mask.count) {
	print_extents (stream, &log->mask.extents);
	print_operators (stream, log->mask.operators);
	print_pattern (stream, "source", &log->mask.source);
	print_pattern (stream, "mask", &log->mask.mask);
	print_clip (stream, &log->mask.clip);

	_cairo_output_stream_printf (stream, "slowest mask: %f%%\n",
				     percent (log->mask.slowest.elapsed,
					      log->mask.elapsed));
	print_record (stream, &log->mask.slowest);

	_cairo_output_stream_printf (stream, "\n");
	if (replay_record (log, &log->mask.slowest, script))
	    _cairo_output_stream_printf (stream, "\n\n");
    }

    _cairo_output_stream_printf (stream, "fill: count %d [no-op %d], elaspsed %f [%f%%]\n",
				 log->fill.count, log->fill.noop,
				 _cairo_time_to_ns (log->fill.elapsed),
				 percent (log->fill.elapsed, total));
    if (log->fill.count) {
	print_extents (stream, &log->fill.extents);
	print_operators (stream, log->fill.operators);
	print_pattern (stream, "source", &log->fill.source);
	print_path (stream, &log->fill.path);
	print_fill_rule (stream, log->fill.fill_rule);
	print_antialias (stream, log->fill.antialias);
	print_clip (stream, &log->fill.clip);

	_cairo_output_stream_printf (stream, "slowest fill: %f%%\n",
				     percent (log->fill.slowest.elapsed,
					      log->fill.elapsed));
	print_record (stream, &log->fill.slowest);

	_cairo_output_stream_printf (stream, "\n");
	if (replay_record (log, &log->fill.slowest, script))
	    _cairo_output_stream_printf (stream, "\n\n");
    }

    _cairo_output_stream_printf (stream, "stroke: count %d [no-op %d], elapsed %f [%f%%]\n",
				 log->stroke.count, log->stroke.noop,
				 _cairo_time_to_ns (log->stroke.elapsed),
				 percent (log->stroke.elapsed, total));
    if (log->stroke.count) {
	print_extents (stream, &log->stroke.extents);
	print_operators (stream, log->stroke.operators);
	print_pattern (stream, "source", &log->stroke.source);
	print_path (stream, &log->stroke.path);
	print_antialias (stream, log->stroke.antialias);
	print_line_caps (stream, log->stroke.caps);
	print_line_joins (stream, log->stroke.joins);
	print_clip (stream, &log->stroke.clip);

	_cairo_output_stream_printf (stream, "slowest stroke: %f%%\n",
				     percent (log->stroke.slowest.elapsed,
					      log->stroke.elapsed));
	print_record (stream, &log->stroke.slowest);

	_cairo_output_stream_printf (stream, "\n");
	if (replay_record (log, &log->stroke.slowest, script))
	    _cairo_output_stream_printf (stream, "\n\n");
    }

    _cairo_output_stream_printf (stream, "glyphs: count %d [no-op %d], elasped %f [%f%%]\n",
				 log->glyphs.count, log->glyphs.noop,
				 _cairo_time_to_ns (log->glyphs.elapsed),
				 percent (log->glyphs.elapsed, total));
    if (log->glyphs.count) {
	print_extents (stream, &log->glyphs.extents);
	print_operators (stream, log->glyphs.operators);
	print_pattern (stream, "source", &log->glyphs.source);
	print_clip (stream, &log->glyphs.clip);

	_cairo_output_stream_printf (stream, "slowest glyphs: %f%%\n",
				     percent (log->glyphs.slowest.elapsed,
					      log->glyphs.elapsed));
	print_record (stream, &log->glyphs.slowest);

	_cairo_output_stream_printf (stream, "\n");
	if (replay_record (log, &log->glyphs.slowest, script))
	    _cairo_output_stream_printf (stream, "\n\n");
    }

    cairo_device_destroy (script);
}

void
cairo_surface_observer_print (cairo_surface_t *abstract_surface,
			      cairo_write_func_t write_func,
			      void *closure)
{
    cairo_output_stream_t *stream;
    cairo_surface_observer_t *surface;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_surface->ref_count)))
	return;

    if (! _cairo_surface_is_observer (abstract_surface))
	return;

    surface = (cairo_surface_observer_t *) abstract_surface;

    stream = _cairo_output_stream_create (write_func, NULL, closure);
    _cairo_observation_print (stream, &surface->log);
    _cairo_output_stream_destroy (stream);
}

double
cairo_surface_observer_elapsed (cairo_surface_t *abstract_surface)
{
    cairo_surface_observer_t *surface;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_surface->ref_count)))
	return -1;

    if (! _cairo_surface_is_observer (abstract_surface))
	return -1;

    surface = (cairo_surface_observer_t *) abstract_surface;
    return _cairo_time_to_ns (_cairo_observation_total_elapsed (&surface->log));
}

void
cairo_device_observer_print (cairo_device_t *abstract_device,
			     cairo_write_func_t write_func,
			     void *closure)
{
    cairo_output_stream_t *stream;
    cairo_device_observer_t *device;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_device->ref_count)))
	return;

    if (! _cairo_device_is_observer (abstract_device))
	return;

    device = (cairo_device_observer_t *) abstract_device;

    stream = _cairo_output_stream_create (write_func, NULL, closure);
    _cairo_observation_print (stream, &device->log);
    _cairo_output_stream_destroy (stream);
}

double
cairo_device_observer_elapsed (cairo_device_t *abstract_device)
{
    cairo_device_observer_t *device;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_device->ref_count)))
	return -1;

    if (! _cairo_device_is_observer (abstract_device))
	return -1;

    device = (cairo_device_observer_t *) abstract_device;
    return _cairo_time_to_ns (_cairo_observation_total_elapsed (&device->log));
}

double
cairo_device_observer_paint_elapsed (cairo_device_t *abstract_device)
{
    cairo_device_observer_t *device;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_device->ref_count)))
	return -1;

    if (! _cairo_device_is_observer (abstract_device))
	return -1;

    device = (cairo_device_observer_t *) abstract_device;
    return _cairo_time_to_ns (device->log.paint.elapsed);
}

double
cairo_device_observer_mask_elapsed (cairo_device_t *abstract_device)
{
    cairo_device_observer_t *device;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_device->ref_count)))
	return -1;

    if (! _cairo_device_is_observer (abstract_device))
	return -1;

    device = (cairo_device_observer_t *) abstract_device;
    return _cairo_time_to_ns (device->log.mask.elapsed);
}

double
cairo_device_observer_fill_elapsed (cairo_device_t *abstract_device)
{
    cairo_device_observer_t *device;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_device->ref_count)))
	return -1;

    if (! _cairo_device_is_observer (abstract_device))
	return -1;

    device = (cairo_device_observer_t *) abstract_device;
    return _cairo_time_to_ns (device->log.fill.elapsed);
}

double
cairo_device_observer_stroke_elapsed (cairo_device_t *abstract_device)
{
    cairo_device_observer_t *device;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_device->ref_count)))
	return -1;

    if (! _cairo_device_is_observer (abstract_device))
	return -1;

    device = (cairo_device_observer_t *) abstract_device;
    return _cairo_time_to_ns (device->log.stroke.elapsed);
}

double
cairo_device_observer_glyphs_elapsed (cairo_device_t *abstract_device)
{
    cairo_device_observer_t *device;

    if (unlikely (CAIRO_REFERENCE_COUNT_IS_INVALID (&abstract_device->ref_count)))
	return -1;

    if (! _cairo_device_is_observer (abstract_device))
	return -1;

    device = (cairo_device_observer_t *) abstract_device;
    return _cairo_time_to_ns (device->log.glyphs.elapsed);
}