C++ cairo_rectangle函数代码示例

static cairo_test_status_t
draw (cairo_t *cr, int width, int height)
{
    const cairo_test_context_t *ctx = cairo_test_get_context (cr);
    cairo_surface_t        *surface;
    cairo_t                *cr2;
    cairo_rectangle_list_t *rectangle_list;
    const char             *phase;
    cairo_bool_t            uses_clip_rects;
    
    surface = cairo_surface_create_similar (cairo_get_group_target (cr),
                                            CAIRO_CONTENT_COLOR, 100, 100);
    /* don't use cr accidentally */
    cr = NULL;
    cr2 = cairo_create (surface);
    cairo_surface_destroy (surface);

    /* Check the surface type so we ignore cairo_copy_clip_rectangle_list failures
     * on surface types that don't use rectangle lists for clipping.
     * Default to FALSE for the internal surface types, (meta, test-fallback, etc.)
     */
    switch (cairo_surface_get_type (surface)) {
    case CAIRO_SURFACE_TYPE_IMAGE:
    case CAIRO_SURFACE_TYPE_XLIB:
    case CAIRO_SURFACE_TYPE_XCB:
    case CAIRO_SURFACE_TYPE_GLITZ:
    case CAIRO_SURFACE_TYPE_WIN32:
    case CAIRO_SURFACE_TYPE_BEOS:
    case CAIRO_SURFACE_TYPE_DIRECTFB:
        uses_clip_rects = TRUE;
	break;
    case CAIRO_SURFACE_TYPE_QUARTZ:
    case CAIRO_SURFACE_TYPE_PDF:
    case CAIRO_SURFACE_TYPE_PS:
    case CAIRO_SURFACE_TYPE_SVG:
    case CAIRO_SURFACE_TYPE_OS2:
    default:
        uses_clip_rects = FALSE;
        break;
    }

    /* first, test basic stuff. This should not be clipped, it should
       return the surface rectangle. */
    phase = "No clip set";
    rectangle_list = cairo_copy_clip_rectangle_list (cr2);
    if (!check_count (ctx, phase, uses_clip_rects, rectangle_list, 1) ||
        !check_clip_extents (ctx, phase, cr2, 0, 0, 100, 100) ||
        !check_rectangles_contain (ctx, phase, uses_clip_rects, rectangle_list, 0, 0, 100, 100)) {
        cairo_rectangle_list_destroy (rectangle_list);
	return CAIRO_TEST_FAILURE;
    }
    cairo_rectangle_list_destroy (rectangle_list);

    /* Test simple clip rect. */
    phase = "Simple clip rect";
    cairo_save (cr2);
    cairo_rectangle (cr2, 10, 10, 80, 80);
    cairo_clip (cr2);
    rectangle_list = cairo_copy_clip_rectangle_list (cr2);
    if (!check_count (ctx, phase, uses_clip_rects, rectangle_list, 1) ||
        !check_clip_extents (ctx, phase, cr2, 10, 10, 80, 80) ||
        !check_rectangles_contain (ctx, phase, uses_clip_rects, rectangle_list, 10, 10, 80, 80)) {
        cairo_rectangle_list_destroy (rectangle_list);
	return CAIRO_TEST_FAILURE;
    }
    cairo_rectangle_list_destroy (rectangle_list);
    cairo_restore (cr2);

    /* Test everything clipped out. */
    phase = "All clipped out";
    cairo_save (cr2);
    cairo_clip (cr2);
    rectangle_list = cairo_copy_clip_rectangle_list (cr2);
    if (!check_count (ctx, phase, uses_clip_rects, rectangle_list, 0)) {
        cairo_rectangle_list_destroy (rectangle_list);
	return CAIRO_TEST_FAILURE;
    }
    cairo_rectangle_list_destroy (rectangle_list);
    cairo_restore (cr2);
    
    /* test two clip rects */
    phase = "Two clip rects";
    cairo_save (cr2);
    cairo_rectangle (cr2, 10, 10, 10, 10);
    cairo_rectangle (cr2, 20, 20, 10, 10);
    cairo_clip (cr2);
    cairo_rectangle (cr2, 15, 15, 10, 10);
    cairo_clip (cr2);
    rectangle_list = cairo_copy_clip_rectangle_list (cr2);
    if (!check_count (ctx, phase, uses_clip_rects, rectangle_list, 2) ||
        !check_clip_extents (ctx, phase, cr2, 15, 15, 10, 10) ||
        !check_rectangles_contain (ctx, phase, uses_clip_rects, rectangle_list, 15, 15, 5, 5) ||
        !check_rectangles_contain (ctx, phase, uses_clip_rects, rectangle_list, 20, 20, 5, 5)) {
        cairo_rectangle_list_destroy (rectangle_list);
	return CAIRO_TEST_FAILURE;
    }
    cairo_rectangle_list_destroy (rectangle_list);
    cairo_restore (cr2);

    /* test non-rectangular clip */
//.........这里部分代码省略.........

//.........这里部分代码省略.........
      double hradius, vradius;

      switch (radial->size)
        {
        case GTK_CSS_EXPLICIT_SIZE:
          hradius = _gtk_css_number_value_get (radial->sizes[0], width);
          vradius = _gtk_css_number_value_get (radial->sizes[1], height);
          break;
        case GTK_CSS_CLOSEST_SIDE:
          hradius = MIN (x, width - x);
          vradius = MIN (y, height - y);
          break;
        case GTK_CSS_FARTHEST_SIDE:
          hradius = MAX (x, width - x);
          vradius = MAX (y, height - y);
          break;
        case GTK_CSS_CLOSEST_CORNER:
          hradius = M_SQRT2 * MIN (x, width - x);
          vradius = M_SQRT2 * MIN (y, height - y);
          break;
        case GTK_CSS_FARTHEST_CORNER:
          hradius = M_SQRT2 * MAX (x, width - x);
          vradius = M_SQRT2 * MAX (y, height - y);
          break;
        default:
          g_assert_not_reached ();
        }

      hradius = MAX (1.0, hradius);
      vradius = MAX (1.0, vradius);

      radius = hradius;
      yscale = vradius / hradius;
    }

  gtk_css_image_radial_get_start_end (radial, radius, &start, &end);

  pattern = cairo_pattern_create_radial (0, 0, 0, 0, 0, radius);
  if (yscale != 1.0)
    {
      cairo_matrix_init_scale (&matrix, 1.0, 1.0 / yscale);
      cairo_pattern_set_matrix (pattern, &matrix);
    }

 if (radial->repeating)
    cairo_pattern_set_extend (pattern, CAIRO_EXTEND_REPEAT);
  else
    cairo_pattern_set_extend (pattern, CAIRO_EXTEND_PAD);

  offset = start;
  last = -1;
  for (i = 0; i < radial->stops->len; i++)
    {
      GtkCssImageRadialColorStop *stop;
      double pos, step;

      stop = &g_array_index (radial->stops, GtkCssImageRadialColorStop, i);

      if (stop->offset == NULL)
        {
          if (i == 0)
            pos = 0.0;
          else if (i + 1 == radial->stops->len)
            pos = 1.0;
          else
            continue;
        }
      else
        pos = _gtk_css_number_value_get (stop->offset, radius) / radius;

      pos = MAX (pos, 0);
      step = pos / (i - last);
      for (last = last + 1; last <= i; last++)
        {
          const GdkRGBA *rgba;

          stop = &g_array_index (radial->stops, GtkCssImageRadialColorStop, last);

          rgba = _gtk_css_rgba_value_get_rgba (stop->color);
          offset += step;

          cairo_pattern_add_color_stop_rgba (pattern,
                                             (offset - start) / (end - start),
                                             rgba->red,
                                             rgba->green,
                                             rgba->blue,
                                             rgba->alpha);
        }

      offset = pos;
      last = i;
    }

  cairo_rectangle (cr, 0, 0, width, height);
  cairo_translate (cr, x, y);
  cairo_set_source (cr, pattern);
  cairo_fill (cr);

  cairo_pattern_destroy (pattern);
}

static void
polygon_view_draw (PolygonView *self, cairo_t *cr)
{
    polygon_t *polygon;
    gdouble sf_x, sf_y, sf;
    gdouble mid, dim;
    gdouble x0,  y0;
    box_t extents;

    extents = self->extents;

    mid = (extents.p2.x + extents.p1.x) / 2.;
    dim = (extents.p2.x - extents.p1.x) / 2. * 1.25;
    sf_x = self->widget.allocation.width / dim / 2;

    mid = (extents.p2.y + extents.p1.y) / 2.;
    dim = (extents.p2.y - extents.p1.y) / 2. * 1.25;
    sf_y = self->widget.allocation.height / dim / 2;

    sf = MIN (sf_x, sf_y);

    mid = (extents.p2.x + extents.p1.x) / 2.;
    dim = sf_x / sf * (extents.p2.x - extents.p1.x) / 2. * 1.25;
    x0 = mid - dim;
    mid = (extents.p2.y + extents.p1.y) / 2.;
    dim = sf_y / sf * (extents.p2.y - extents.p1.y) / 2. * 1.25;
    y0 = mid - dim;

    if (self->pixmap_width != self->widget.allocation.width ||
	self->pixmap_height != self->widget.allocation.height)
    {
	cairo_surface_destroy (self->pixmap);
	self->pixmap = pixmap_create (self, cairo_get_target (cr));
	self->pixmap_width = self->widget.allocation.width;
	self->pixmap_height = self->widget.allocation.height;
    }

    cairo_set_source_surface (cr, self->pixmap, 0, 0);
    cairo_paint (cr);

    if (self->polygons == NULL)
	return;

    /* draw a zoom view of the area around the mouse */
    if (1) {
	double zoom = self->mag_zoom;
	int size = self->mag_size;
	int mag_x = self->mag_x;
	int mag_y = self->mag_y;

	if (1) {
	    if (self->px + size < self->widget.allocation.width/2)
		mag_x = self->px + size/4;
	    else
		mag_x = self->px - size/4 - size;
	    mag_y = self->py - size/2;
	    if (mag_y < 0)
		mag_y = 0;
	    if (mag_y + size > self->widget.allocation.height)
		mag_y = self->widget.allocation.height - size;
	}

	cairo_save (cr); {
	    /* bottom right */
	    cairo_rectangle (cr, mag_x, mag_y, size, size);
	    cairo_stroke_preserve (cr);
	    cairo_set_source_rgb (cr, 1, 1, 1);
	    cairo_fill_preserve (cr);
	    cairo_clip (cr);

	    /* compute roi in extents */
	    cairo_translate (cr, mag_x + size/2, mag_y + size/2);

	    cairo_save (cr); {
		cairo_scale (cr, zoom, zoom);
		cairo_translate (cr, -(self->px / sf + x0), -(self->py /sf + y0));
		for (polygon = self->polygons; polygon; polygon = polygon->next) {
		    if (polygon->num_edges == 0)
			continue;

		    draw_polygon (cr, polygon, zoom);
		}

		if (highlight != -1) {
		    cairo_move_to (cr, extents.p1.x, highlight);
		    cairo_line_to (cr, extents.p2.x, highlight);
		    cairo_set_source_rgb (cr, 0, .7, 0);
		    cairo_save (cr);
		    cairo_identity_matrix (cr);
		    cairo_set_line_width (cr, 1.);
		    cairo_stroke (cr);
		    cairo_restore (cr);
		}
	    } cairo_restore (cr);

	    /* grid */
	    cairo_save (cr); {
		int i;

		cairo_translate (cr,
//.........这里部分代码省略.........

static void draw_page(GtkPrintOperation *operation, GtkPrintContext *context,
					  gint page_nr, gpointer user_data)
{
	DocInfo *dinfo = user_data;
	GeanyEditor *editor;
	cairo_t *cr;
	gdouble width, height;
	gdouble x = 0.0, y = 0.0;
	/*gint layout_h;*/
	gint count;
	GString *str;

	if (dinfo == NULL || page_nr >= dinfo->n_pages)
		return;

	editor = dinfo->doc->editor;

	if (dinfo->n_pages > 0)
	{
		gdouble fraction = (page_nr + 1) / (gdouble) dinfo->n_pages;
		gchar *text = g_strdup_printf(_("Page %d of %d"), page_nr, dinfo->n_pages);
		gtk_progress_bar_set_fraction(GTK_PROGRESS_BAR(main_widgets.progressbar), fraction);
		gtk_progress_bar_set_text(GTK_PROGRESS_BAR(main_widgets.progressbar), text);
		g_free(text);
	}

#ifdef GEANY_PRINT_DEBUG
	geany_debug("draw_page = %d, pages = %d, (real) lines_per_page = %d",
		page_nr, dinfo->n_pages, dinfo->lines_per_page);
#endif

	str = g_string_sized_new(256);
	cr = gtk_print_context_get_cairo_context(context);
	width = gtk_print_context_get_width(context);
	height = gtk_print_context_get_height(context);

	cairo_set_source_rgb(cr, 0, 0, 0);
#ifdef GEANY_PRINT_DEBUG
	cairo_set_line_width(cr, 0.2);
	cairo_rectangle(cr, 0, 0, width, height);
	cairo_stroke(cr);
#endif
	cairo_move_to(cr, 0, 0);

	pango_layout_set_width(dinfo->layout, width * PANGO_SCALE);
	pango_layout_set_alignment(dinfo->layout, PANGO_ALIGN_LEFT);
	pango_layout_set_ellipsize(dinfo->layout, FALSE);
	pango_layout_set_justify(dinfo->layout, FALSE);

	if (printing_prefs.print_page_header)
		add_page_header(dinfo, cr, width, page_nr);

	count = 0;	/* the actual line counter for the current page, might be different from
				 * dinfo->cur_line due to possible line breaks */
	while (count < dinfo->lines_per_page)
	{
		gchar c = 'a';
		gint style = -1;
		PangoAttrList *layout_attr;
		PangoAttribute *attr;
		gint colours[3] = { 0 };
		gboolean add_linenumber = TRUE;
		gboolean at_eol;

		while (count < dinfo->lines_per_page && c != '\0')
		{
			at_eol = FALSE;

			g_string_erase(str, 0, str->len); /* clear the string */

			/* line numbers */
			if (printing_prefs.print_line_numbers && add_linenumber)
			{
				/* if we had a wrapped line on the last page which needs to be continued, don't
				 * add a line number */
				if (dinfo->long_line)
				{
					add_linenumber = FALSE;
				}
				else
				{
					gchar *line_number = NULL;
					gint cur_line_number_margin = get_line_numbers_arity(dinfo->cur_line + 1);
					gchar *fill = g_strnfill(
						dinfo->max_line_number_margin - cur_line_number_margin - 1, ' ');

					line_number = g_strdup_printf("%s%d ", fill, dinfo->cur_line + 1);
					g_string_append(str, line_number);
					dinfo->cur_line++; /* increase document line */
					add_linenumber = FALSE;
					style = STYLE_LINENUMBER;
					c = 'a'; /* dummy value */
					g_free(fill);
					g_free(line_number);
				}
			}
			/* data */
			else
			{
				style = sci_get_style_at(dinfo->doc->editor->sci, dinfo->cur_pos);
//.........这里部分代码省略.........

//.........这里部分代码省略.........
        double x0, y0, x1, y1;
        switch(lib->splitline_rotation)
        {
          case 0:
            x0 = 0.0;
            y0 = 0.0;
            x1 = buf.width * lib->splitline_x;
            y1 = buf.height;
            break;
          case 1:
            x0 = 0.0;
            y0 = 0.0;
            x1 = buf.width;
            y1 = buf.height * lib->splitline_y;
            break;
          case 2:
            x0 = buf.width * lib->splitline_x;
            y0 = 0.0;
            x1 = buf.width;
            y1 = buf.height;
            break;
          case 3:
            x0 = 0.0;
            y0 = buf.height * lib->splitline_y;
            x1 = buf.width;
            y1 = buf.height;
            break;
          default:
            fprintf(stderr, "OMFG, the world will collapse, this shouldn't be reachable!\n");
            dt_pthread_mutex_unlock(&cam->live_view_pixbuf_mutex);
            return;
        }

        cairo_rectangle(cr, x0, y0, x1, y1);
        cairo_clip(cr);
      }

      cairo_set_source_surface(cr, surface, 0, 0);
      // set filter no nearest:
      // in skull mode, we want to see big pixels.
      // in 1 iir mode for the right mip, we want to see exactly what the pipe gave us, 1:1 pixel for pixel.
      // in between, filtering just makes stuff go unsharp.
      if((buf.width <= 8 && buf.height <= 8) || fabsf(scale - 1.0f) < 0.01f)
        cairo_pattern_set_filter(cairo_get_source(cr), CAIRO_FILTER_NEAREST);
      cairo_rectangle(cr, 0, 0, buf.width, buf.height);
      int overlay_modes_index = dt_bauhaus_combobox_get(lib->overlay_mode);
      if(overlay_modes_index >= 0)
      {
        cairo_operator_t mode = _overlay_modes[overlay_modes_index];
        cairo_set_operator(cr, mode);
      }
      cairo_fill(cr);
      cairo_set_operator(cr, CAIRO_OPERATOR_OVER);
      cairo_surface_destroy(surface);
    }
    cairo_restore(cr);
    if(buf.buf) dt_mipmap_cache_release(darktable.mipmap_cache, &buf);
    if(img) dt_image_cache_read_release(darktable.image_cache, img);

    // ON CANVAS CONTROLS
    if(use_splitline)
    {
      scale = fminf(1.0, fminf(w / pw, h / ph));

      // image coordinates
      lib->overlay_x0 = 0.5 * (width - pw * scale);

static gboolean
gimp_fg_bg_view_expose (GtkWidget      *widget,
                        GdkEventExpose *eevent)
{
  GimpFgBgView *view   = GIMP_FG_BG_VIEW (widget);
  GtkStyle     *style  = gtk_widget_get_style (widget);
  GdkWindow    *window = gtk_widget_get_window (widget);
  cairo_t      *cr;
  GtkAllocation allocation;
  gint          rect_w, rect_h;
  GimpRGB       color;

  if (! gtk_widget_is_drawable (widget))
    return FALSE;

  cr = gdk_cairo_create (eevent->window);

  gdk_cairo_region (cr, eevent->region);
  cairo_clip (cr);

  gtk_widget_get_allocation (widget, &allocation);

  cairo_translate (cr, allocation.x, allocation.y);

  rect_w = allocation.width  * 3 / 4;
  rect_h = allocation.height * 3 / 4;

  if (! view->transform)
    gimp_fg_bg_view_create_transform (view);

  /*  draw the background area  */

  if (view->context)
    {
      gimp_context_get_background (view->context, &color);

      if (view->transform)
        gimp_color_transform_process_pixels (view->transform,
                                             babl_format ("R'G'B'A double"),
                                             &color,
                                             babl_format ("R'G'B'A double"),
                                             &color,
                                             1);

      gimp_cairo_set_source_rgb (cr, &color);

      cairo_rectangle (cr,
                       allocation.width  - rect_w + 1,
                       allocation.height - rect_h + 1,
                       rect_w - 2,
                       rect_h - 2);
      cairo_fill (cr);
    }

  gtk_paint_shadow (style, window, GTK_STATE_NORMAL,
                    GTK_SHADOW_IN,
                    NULL, widget, NULL,
                    allocation.x + allocation.width  - rect_w,
                    allocation.y + allocation.height - rect_h,
                    rect_w, rect_h);

  /*  draw the foreground area  */

  if (view->context)
    {
      gimp_context_get_foreground (view->context, &color);

      if (view->transform)
        gimp_color_transform_process_pixels (view->transform,
                                             babl_format ("R'G'B'A double"),
                                             &color,
                                             babl_format ("R'G'B'A double"),
                                             &color,
                                             1);

      gimp_cairo_set_source_rgb (cr, &color);

      cairo_rectangle (cr, 1, 1, rect_w - 2, rect_h - 2);
      cairo_fill (cr);
    }

  gtk_paint_shadow (style, window, GTK_STATE_NORMAL,
                    GTK_SHADOW_OUT,
                    NULL, widget, NULL,
                    allocation.x, allocation.y, rect_w, rect_h);

  cairo_destroy (cr);

  return TRUE;
}

static gboolean _lib_histogram_draw_callback(GtkWidget *widget, cairo_t *crf, gpointer user_data)
{
  dt_lib_module_t *self = (dt_lib_module_t *)user_data;
  dt_lib_histogram_t *d = (dt_lib_histogram_t *)self->data;

  dt_develop_t *dev = darktable.develop;
  uint32_t *hist = dev->histogram;
  float hist_max = dev->histogram_type == DT_DEV_HISTOGRAM_LINEAR ? dev->histogram_max
                                                                  : logf(1.0 + dev->histogram_max);
  const int inset = DT_HIST_INSET;
  GtkAllocation allocation;
  gtk_widget_get_allocation(widget, &allocation);
  int width = allocation.width, height = allocation.height;
  cairo_surface_t *cst = dt_cairo_image_surface_create(CAIRO_FORMAT_ARGB32, width, height);
  cairo_t *cr = cairo_create(cst);

  gtk_render_background(gtk_widget_get_style_context(widget), cr, 0, 0, allocation.width, allocation.height);

  cairo_translate(cr, 4 * inset, inset);
  width -= 2 * 4 * inset;
  height -= 2 * inset;

  if(d->mode_x == 0)
  {
    d->color_w = 0.06 * width;
    d->button_spacing = 0.01 * width;
    d->button_h = 0.06 * width;
    d->button_y = d->button_spacing;
    d->mode_w = d->color_w;
    d->mode_x = width - 3 * (d->color_w + d->button_spacing) - (d->mode_w + d->button_spacing);
    d->red_x = width - 3 * (d->color_w + d->button_spacing);
    d->green_x = width - 2 * (d->color_w + d->button_spacing);
    d->blue_x = width - (d->color_w + d->button_spacing);
  }

  // TODO: probably this should move to the configure-event callback! That would be future proof if we ever
  // (again) allow to resize the side panels.
  const gint stride = cairo_format_stride_for_width(CAIRO_FORMAT_ARGB32, width);

  // this code assumes that the first expose comes before the first (preview) pipe is processed and that the
  // size of the widget doesn't change!
  if(dev->histogram_waveform_width == 0)
  {
    dev->histogram_waveform = (uint32_t *)calloc(height * stride / 4, sizeof(uint32_t));
    dev->histogram_waveform_stride = stride;
    dev->histogram_waveform_height = height;
    dev->histogram_waveform_width = width;
    //     return TRUE; // there are enough expose events following ...
  }

#if 1
  // draw shadow around
  float alpha = 1.0f;
  cairo_set_line_width(cr, 0.2);
  for(int k = 0; k < inset; k++)
  {
    cairo_rectangle(cr, -k, -k, width + 2 * k, height + 2 * k);
    cairo_set_source_rgba(cr, 0, 0, 0, alpha);
    alpha *= 0.5f;
    cairo_fill(cr);
  }
  cairo_set_line_width(cr, 1.0);
#else
  cairo_set_line_width(cr, 1.0);
  cairo_set_source_rgb(cr, .1, .1, .1);
  cairo_rectangle(cr, 0, 0, width, height);
  cairo_stroke(cr);
#endif

  cairo_rectangle(cr, 0, 0, width, height);
  cairo_clip(cr);

  cairo_set_source_rgb(cr, .3, .3, .3);
  cairo_rectangle(cr, 0, 0, width, height);
  cairo_fill(cr);
  if(d->highlight == 1)
  {
    cairo_set_source_rgb(cr, .5, .5, .5);
    cairo_rectangle(cr, 0, 0, .2 * width, height);
    cairo_fill(cr);
  }
  else if(d->highlight == 2)
  {
    cairo_set_source_rgb(cr, .5, .5, .5);
    cairo_rectangle(cr, 0.2 * width, 0, width, height);
    cairo_fill(cr);
  }

  // draw grid
  cairo_set_line_width(cr, .4);
  cairo_set_source_rgb(cr, .1, .1, .1);
  if(dev->histogram_type == DT_DEV_HISTOGRAM_WAVEFORM)
    dt_draw_waveform_lines(cr, 0, 0, width, height);
  else
    dt_draw_grid(cr, 4, 0, 0, width, height);

  if(hist_max > 0.0f)
  {
    cairo_save(cr);
    if(dev->histogram_type == DT_DEV_HISTOGRAM_WAVEFORM)
//.........这里部分代码省略.........

static cairo_test_status_t
column_triangles (cairo_t *cr, int width, int height)
{
    int x, y, i, channel;

    state = 0x12345678;

    cairo_set_source_rgb (cr, 0.0, 0.0, 0.0);
    cairo_paint (cr);

#if GENERATE_REFERENCE
    for (x = 0; x < WIDTH; x++) {
	cairo_set_source_rgba (cr, 1, 1, 1, x * 0.5 / WIDTH);
	cairo_rectangle (cr, x, 0, 1, HEIGHT);
	cairo_fill (cr);
    }
#else
    cairo_set_operator (cr, CAIRO_OPERATOR_ADD);
    for (channel = 0; channel < 3; channel++) {
	switch (channel) {
	default:
	case 0: cairo_set_source_rgb (cr, 1.0, 0.0, 0.0); break;
	case 1: cairo_set_source_rgb (cr, 0.0, 1.0, 0.0); break;
	case 2: cairo_set_source_rgb (cr, 0.0, 0.0, 1.0); break;
	}

	for (x = 0; x < WIDTH; x++) {
	    double step = x / (double) (2 * WIDTH);
	    for (y = 0; y < HEIGHT; y++) {
		for (i = 0; i < PRECISION; i++) {
		    double dy = random_offset (WIDTH - x, FALSE);

		    /*
		     * We want to test some sharing of edges to further
		     * stress the rasterisers, so instead of using one
		     * tall triangle, it is split into two, with vertical
		     * edges on either side that may co-align with their
		     * neighbours:
		     *
		     *  s ---  .      ---
		     *  t  |   |\      |
		     *  e  |   | \     |
		     *  p ---  ....    |  2 * step = x / WIDTH
		     *          \ |    |
		     *           \|    |
		     *            .   ---
		     *        |---|
		     *     1 / PRECISION
		     *
		     * Each column contains two triangles of width one quantum and
		     * total height of (x / WIDTH), thus the total area covered by all
		     * columns in each pixel is .5 * (x / WIDTH).
		     */

		    cairo_move_to (cr, x + i / (double) PRECISION, y + dy);
		    cairo_rel_line_to (cr, 0, step);
		    cairo_rel_line_to (cr, 1 / (double) PRECISION, step);
		    cairo_rel_line_to (cr, 0, -step);
		    cairo_close_path (cr);
		}
		cairo_fill (cr); /* do these per-pixel due to the extra volume of edges */
	    }
	}
    }
#endif

    return CAIRO_TEST_SUCCESS;
}

static void
eom_print_preview_draw (EomPrintPreview *preview, cairo_t *cr)
{
	EomPrintPreviewPrivate *priv;
	GtkWidget *area;
	GtkAllocation allocation;
	gint x0, y0;
	GtkStyle *style;
	gboolean has_focus;

	priv = preview->priv;
	area = priv->area;

	has_focus = gtk_widget_has_focus (area);

	style = gtk_widget_get_style (area);

	gtk_widget_get_allocation (area, &allocation);

	/* draw the page */
 	gdk_cairo_set_source_color (cr, &style->white);
 	cairo_rectangle (cr, 0, 0, allocation.width, allocation.height);
 	cairo_fill (cr);

	/* draw the page margins */
	gdk_cairo_set_source_color (cr, &style->black);
	cairo_set_line_width (cr, 0.1);
	cairo_rectangle (cr,
			 priv->l_rmargin, priv->t_rmargin,
			 allocation.width - priv->l_rmargin - priv->r_rmargin,
			 allocation.height - priv->t_rmargin - priv->b_rmargin);
	cairo_stroke (cr);

	get_current_image_coordinates (preview, &x0, &y0);

	if (priv->flag_create_surface) {
		create_surface (preview);
	}

	if (priv->surface) {
		cairo_set_source_surface (cr, priv->surface, x0, y0);
		cairo_paint (cr);
	} else if (priv->image_scaled) {
		/* just in the remote case we don't have the surface */

		/* adjust (x0, y0) to the new scale */
		gdouble scale = priv->i_scale * priv->p_scale *
			gdk_pixbuf_get_width (priv->image) / gdk_pixbuf_get_width (priv->image_scaled);
		x0 /= scale;
		y0 /= scale;

		cairo_scale (cr, scale, scale);
		gdk_cairo_set_source_pixbuf (cr, priv->image_scaled, x0, y0);
		cairo_paint (cr);
	} else if (priv->image) {
		/* just in the remote case we don't have the surface */

		/* adjust (x0, y0) to the new scale */
		x0 /=  priv->i_scale * priv->p_scale;
		y0 /=  priv->i_scale * priv->p_scale;

		cairo_scale (cr, priv->i_scale*priv->p_scale, priv->i_scale*priv->p_scale);
		gdk_cairo_set_source_pixbuf (cr, priv->image, x0, y0);
		cairo_paint (cr);
	}

	if (has_focus) {
		gtk_paint_focus (style, gtk_widget_get_window (area),
				 GTK_STATE_NORMAL, NULL, NULL, NULL,
				 0, 0, allocation.width, allocation.height);
	}
}

/**
 * ags_note_edit_draw_position:
 * @note_edit: the #AgsNoteEdit
 * @cr: the #cairo_t surface
 *
 * Draws the cursor.
 *
 * Since: 0.4
 */
void
ags_note_edit_draw_position(AgsNoteEdit *note_edit, cairo_t *cr)
{
  guint selected_x, selected_y;
  guint x_offset[2], y_offset[2];
  guint x, y, width, height;
  gint size_width, size_height;

  selected_x = note_edit->selected_x * note_edit->control_unit.control_width;
  selected_y = note_edit->selected_y * note_edit->control_height;

  size_width = GTK_WIDGET(note_edit->drawing_area)->allocation.width;
  size_height = GTK_WIDGET(note_edit->drawing_area)->allocation.height;

  x_offset[0] = (guint) gtk_range_get_value(GTK_RANGE(note_edit->hscrollbar));
  x_offset[1] = x_offset[0] + (guint) size_width;

  y_offset[0] = (guint) gtk_range_get_value(GTK_RANGE(note_edit->vscrollbar));
  y_offset[1] = y_offset[0] + (guint) size_height;

  /* calculate horizontally values */
  if(selected_x < x_offset[0]){
    if(selected_x + note_edit->control_current.control_width > x_offset[0]){
      x = 0;
      width = selected_x + note_edit->control_current.control_width - x_offset[0];
    }else{
      return;
    }
  }else if(selected_x > x_offset[1]){
    return;
  }else{
    x = selected_x - x_offset[0];

    if(selected_x + note_edit->control_current.control_width < x_offset[1]){
      width = note_edit->control_current.control_width;
    }else{
      width = x_offset[1] - (selected_x + note_edit->control_current.control_width);
    }
  }

  /* calculate vertically values */
  if(selected_y < y_offset[0]){
    if(selected_y + note_edit->control_height > y_offset[0]){
      y = 0;
      height = selected_y + note_edit->control_height - y_offset[0];
    }else{
      return;
    }
  }else if(selected_y > y_offset[1]){
    return;
  }else{
    y = selected_y - y_offset[0];

    if(selected_y + note_edit->control_height < y_offset[1]){
      height = note_edit->control_height;
    }else{
      height = y_offset[1] - (selected_y + note_edit->control_height);
    }
  }

  /* draw */
  cairo_set_source_rgba(cr, 0.25, 0.5, 1.0, 0.5);
  cairo_rectangle(cr, (double) x, (double) y, (double) width, (double) height);
  cairo_fill(cr);
}

/**
 * ags_note_edit_draw_notation:
 * @note_edit: the #AgsNoteEdit
 * @cr: the #cairo_t surface
 *
 * Draw the #AgsNotation of selected #AgsMachine on @note_edit.
 *
 * Since: 0.4
 */
void
ags_note_edit_draw_notation(AgsNoteEdit *note_edit, cairo_t *cr)
{
  AgsMachine *machine;
  AgsEditor *editor;
  GtkWidget *widget;
  AgsNote *note;
  GList *list_notation, *list_note;
  guint x_offset;
  guint control_height;
  guint x, y, width, height;
  gint selected_channel;
  gint i;

  editor = (AgsEditor *) gtk_widget_get_ancestor(GTK_WIDGET(note_edit),
						 AGS_TYPE_EDITOR);

  if(editor->selected_machine == NULL ||
     (machine = editor->selected_machine) == NULL ||
     machine->audio->notation == NULL)
    return;

  widget = (GtkWidget *) note_edit->drawing_area;

  cairo_set_source_rgb(cr, 1.0, 1.0, 1.0);

  i = 0;

  while((selected_channel = ags_notebook_next_active_tab(editor->notebook,
							 i)) != -1){
    list_notation = g_list_nth(machine->audio->notation,
			       selected_channel);
    list_note = AGS_NOTATION(list_notation->data)->notes;

    control_height = note_edit->control_height - 2 * note_edit->control_margin_y;

    x_offset = (guint) GTK_RANGE(note_edit->hscrollbar)->adjustment->value;

    /* draw controls smaller than note_edit->nth_x */
    while(list_note != NULL && (note = (AgsNote *) list_note->data)->x[0] < note_edit->control_unit.nth_x){
      if(note->x[1] >= note_edit->control_unit.nth_x){
	if(note->y >= note_edit->nth_y && note->y <= note_edit->stop_y){
	  x = 0;
	  y = (note->y - note_edit->nth_y) * note_edit->control_height + note_edit->y0 + note_edit->control_margin_y;

	  width = (guint) ((double) note->x[1] * note_edit->control_unit.control_width - (double) x_offset);

	  if(width > widget->allocation.width)
	    width = widget->allocation.width;

	  height = control_height;

	  /* draw note */
	  cairo_rectangle(cr, (double) x, (double) y, (double) width, (double) height);
	  cairo_fill(cr);

	  /* check if note is selected */
	  if((AGS_NOTE_IS_SELECTED & (note->flags)) != 0){
	    cairo_set_source_rgba(cr, 1.0, 0.0, 0.0, 0.7);

	    cairo_rectangle(cr, (double) x, (double) y, (double) width, (double) height);
	    cairo_stroke(cr);

	    cairo_set_source_rgb(cr, 1.0, 1.0, 1.0);
	  }
	}else if(note->y == (note_edit->nth_y - 1) && note_edit->y0 != 0){
	  if(note_edit->y0 > note_edit->control_margin_y){
	    x = 0;
	    width = (guint) ((double) note->x[1] * (double) note_edit->control_unit.control_width - x_offset);

	    if(width > widget->allocation.width)
	      width = widget->allocation.width;

	    if(note_edit->y0 > control_height + note_edit->control_margin_y){
	      y = note_edit->y0 - (control_height + note_edit->control_margin_y);
	      height = control_height;
	    }else{
	      y = 0;
	      height = note_edit->y0 - note_edit->control_margin_y;
	    }

	    /* draw note */
	    cairo_rectangle(cr, (double) x, (double) y, (double) width, (double) height);
	    cairo_fill(cr);

	    /* check if note is selected */
	    if((AGS_NOTE_IS_SELECTED & (note->flags)) != 0){
	      cairo_set_source_rgba(cr, 1.0, 0.0, 0.0, 0.7);
	    
	      cairo_rectangle(cr, (double) x, (double) y, (double) width, (double) height);
	      cairo_stroke(cr);
//.........这里部分代码省略.........

/**
 * ags_note_edit_draw_segment:
 * @note_edit: the #AgsNoteEdit
 * @cr: the #cairo_t surface
 *
 * Draws horizontal and vertical lines.
 *
 * Since: 0.4
 */
void
ags_note_edit_draw_segment(AgsNoteEdit *note_edit, cairo_t *cr)
{
  AgsEditor *editor;
  GtkWidget *widget;

  double tact;
  guint i, j;
  guint j_set;

  widget = (GtkWidget *) note_edit->drawing_area;

  editor = (AgsEditor *) gtk_widget_get_ancestor(GTK_WIDGET(note_edit),
						 AGS_TYPE_EDITOR);

  cairo_set_source_rgb(cr, 0.0, 0.0, 0.0);
  cairo_rectangle(cr, 0.0, 0.0, (double) widget->allocation.width, (double) widget->allocation.height);
  cairo_fill(cr);

  cairo_set_line_width(cr, 1.0);

  cairo_set_source_rgb(cr, 0.8, 0.8, 0.8);

  for(i = note_edit->y0 ; i < note_edit->height;){
    cairo_move_to(cr, 0.0, (double) i);
    cairo_line_to(cr, (double) note_edit->width, (double) i);
    cairo_stroke(cr);

    i += note_edit->control_height;
  }

  cairo_move_to(cr, 0.0, (double) i);
  cairo_line_to(cr, (double) note_edit->width, (double) i);
  cairo_stroke(cr);

  tact = exp2((double) gtk_combo_box_get_active(editor->toolbar->zoom) - 4.0);

  i = note_edit->control_current.x0;
  
  if(i < note_edit->width &&
     tact > 1.0 ){
    j_set = note_edit->control_current.nth_x % ((guint) tact);
    cairo_set_source_rgb(cr, 0.6, 0.6, 0.6);

    if(j_set != 0){
      j = j_set;
      goto ags_note_edit_draw_segment0;
    }
  }

  for(; i < note_edit->width; ){
    cairo_set_source_rgb(cr, 1.0, 1.0, 0.0);
    
    cairo_move_to(cr, (double) i, 0.0);
    cairo_line_to(cr, (double) i, (double) note_edit->height);
    cairo_stroke(cr);
    
    i += note_edit->control_current.control_width;
    
    cairo_set_source_rgb(cr, 0.6, 0.6, 0.6);
    
    for(j = 1; i < note_edit->width && j < tact; j++){
    ags_note_edit_draw_segment0:
      cairo_move_to(cr, (double) i, 0.0);
      cairo_line_to(cr, (double) i, (double) note_edit->height);
      cairo_stroke(cr);
      
      i += note_edit->control_current.control_width;
    }
  }
}

static gboolean
dt_iop_basecurve_expose(GtkWidget *widget, GdkEventExpose *event, gpointer user_data)
{
  dt_iop_module_t *self = (dt_iop_module_t *)user_data;
  dt_iop_basecurve_gui_data_t *c = (dt_iop_basecurve_gui_data_t *)self->gui_data;
  dt_iop_basecurve_params_t *p = (dt_iop_basecurve_params_t *)self->params;

  int nodes = p->basecurve_nodes[0];
  dt_iop_basecurve_node_t *basecurve = p->basecurve[0];
  if(c->minmax_curve_type != p->basecurve_type[0] || c->minmax_curve_nodes != p->basecurve_nodes[0])
  {
    dt_draw_curve_destroy(c->minmax_curve);
    c->minmax_curve = dt_draw_curve_new(0.0, 1.0, p->basecurve_type[0]);
    c->minmax_curve_nodes = p->basecurve_nodes[0];
    c->minmax_curve_type = p->basecurve_type[0];
    for(int k=0; k<p->basecurve_nodes[0]; k++)
      (void)dt_draw_curve_add_point(c->minmax_curve, p->basecurve[0][k].x, p->basecurve[0][k].y);
  }
  else
  {
    for(int k=0; k<p->basecurve_nodes[0]; k++)
      dt_draw_curve_set_point(c->minmax_curve, k, p->basecurve[0][k].x, p->basecurve[0][k].y);
  }
  dt_draw_curve_t *minmax_curve = c->minmax_curve;
  dt_draw_curve_calc_values(minmax_curve, 0.0, 1.0, DT_IOP_TONECURVE_RES, c->draw_xs, c->draw_ys);

  const float xm = basecurve[nodes-1].x;
  const float x[4] = {0.7f*xm, 0.8f*xm, 0.9f*xm, 1.0f*xm};
  const float y[4] = {c->draw_ys[CLAMP((int)(x[0]*DT_IOP_TONECURVE_RES), 0, DT_IOP_TONECURVE_RES-1)],
                      c->draw_ys[CLAMP((int)(x[1]*DT_IOP_TONECURVE_RES), 0, DT_IOP_TONECURVE_RES-1)],
                      c->draw_ys[CLAMP((int)(x[2]*DT_IOP_TONECURVE_RES), 0, DT_IOP_TONECURVE_RES-1)],
                      c->draw_ys[CLAMP((int)(x[3]*DT_IOP_TONECURVE_RES), 0, DT_IOP_TONECURVE_RES-1)]
                     };
  float unbounded_coeffs[3];
  dt_iop_estimate_exp(x, y, 4, unbounded_coeffs);

  const int inset = DT_GUI_CURVE_EDITOR_INSET;
  GtkAllocation allocation;
  gtk_widget_get_allocation(widget, &allocation);
  int width = allocation.width, height = allocation.height;
  cairo_surface_t *cst = cairo_image_surface_create(CAIRO_FORMAT_ARGB32, width, height);
  cairo_t *cr = cairo_create(cst);
  // clear bg
  cairo_set_source_rgb (cr, .2, .2, .2);
  cairo_paint(cr);

  cairo_translate(cr, inset, inset);
  width -= 2*inset;
  height -= 2*inset;

#if 0
  // draw shadow around
  float alpha = 1.0f;
  for(int k=0; k<inset; k++)
  {
    cairo_rectangle(cr, -k, -k, width + 2*k, height + 2*k);
    cairo_set_source_rgba(cr, 0, 0, 0, alpha);
    alpha *= 0.6f;
    cairo_fill(cr);
  }
#else
  cairo_set_line_width(cr, 1.0);
  cairo_set_source_rgb (cr, .1, .1, .1);
  cairo_rectangle(cr, 0, 0, width, height);
  cairo_stroke(cr);
#endif

  cairo_set_source_rgb (cr, .3, .3, .3);
  cairo_rectangle(cr, 0, 0, width, height);
  cairo_fill(cr);

  cairo_translate(cr, 0, height);
  cairo_scale(cr, 1.0f, -1.0f);

  // draw grid
  cairo_set_line_width(cr, .4);
  cairo_set_source_rgb (cr, .1, .1, .1);
  if(c->loglogscale)
    dt_draw_loglog_grid(cr, 4, 0, 0, width, height, c->loglogscale);
  else
    dt_draw_grid(cr, 4, 0, 0, width, height);

  // draw nodes positions
  cairo_set_line_width(cr, 1.);
  cairo_set_source_rgb(cr, 0.6, 0.6, 0.6);
  for(int k=0; k<nodes; k++)
  {
    const float x = to_log(basecurve[k].x, c->loglogscale), y = to_log(basecurve[k].y, c->loglogscale);
    cairo_arc(cr, x*width, y*height, 3, 0, 2.*M_PI);
    cairo_stroke(cr);
  }

  // draw selected cursor
  cairo_set_line_width(cr, 1.);

  if(c->selected >= 0)
  {
    cairo_set_source_rgb(cr, .9, .9, .9);
    const float x = to_log(basecurve[c->selected].x, c->loglogscale), y = to_log(basecurve[c->selected].y, c->loglogscale);
    cairo_arc(cr, x*width, y*height, 4, 0, 2.*M_PI);
//.........这里部分代码省略.........

/* 
 * render functions 
 */ 
static void
begin_render(DiaRenderer *self, const Rectangle *update)
{
  DiaCairoRenderer *renderer = DIA_CAIRO_RENDERER (self);
  real onedu = 0.0;
  real lmargin = 0.0, tmargin = 0.0;
  gboolean paginated = renderer->surface && /* only with our own pagination, not GtkPrint */
    cairo_surface_get_type (renderer->surface) == CAIRO_SURFACE_TYPE_PDF && !renderer->skip_show_page;

  if (renderer->surface && !renderer->cr)
    renderer->cr = cairo_create (renderer->surface);
  else
    g_assert (renderer->cr);

  /* remember current state, so we can start from new with every page */
  cairo_save (renderer->cr);

  if (paginated && renderer->dia) {
    DiagramData *data = renderer->dia;
    /* Dia's paper.width already contains the scale, cairo needs it without 
     * Similar for margins, Dia's without, but cairo wants them?
     */
    real width = (data->paper.lmargin + data->paper.width * data->paper.scaling + data->paper.rmargin)
          * (72.0 / 2.54) + 0.5;
    real height = (data->paper.tmargin + data->paper.height * data->paper.scaling + data->paper.bmargin)
           * (72.0 / 2.54) + 0.5;
    /* "Changes the size of a PDF surface for the current (and
     * subsequent) pages." Pagination setup? */
    cairo_pdf_surface_set_size (renderer->surface, width, height);
    lmargin = data->paper.lmargin / data->paper.scaling;
    tmargin = data->paper.tmargin / data->paper.scaling;
  }

  cairo_scale (renderer->cr, renderer->scale, renderer->scale);
  /* to ensure no clipping at top/left we need some extra gymnastics,
   * otherwise a box with a line witdh one one pixel might loose the
   * top/left border as in bug #147386 */
  ensure_minimum_one_device_unit (renderer, &onedu);

  if (update && paginated) {
    cairo_rectangle (renderer->cr, lmargin, tmargin,
                     update->right - update->left, update->bottom - update->top);
    cairo_clip (renderer->cr);
    cairo_translate (renderer->cr, -update->left + lmargin, -update->top + tmargin);
  } else
    cairo_translate (renderer->cr, -renderer->dia->extents.left + onedu, -renderer->dia->extents.top + onedu);
  /* no more blurred UML diagrams */
  cairo_set_antialias (renderer->cr, CAIRO_ANTIALIAS_NONE);

  /* clear background */
  if (renderer->with_alpha)
    {
      cairo_set_operator (renderer->cr, CAIRO_OPERATOR_SOURCE);
      cairo_set_source_rgba (renderer->cr,
                             renderer->dia->bg_color.red, 
                             renderer->dia->bg_color.green, 
                             renderer->dia->bg_color.blue,
                             0.0);
    }
  else
    {
      cairo_set_source_rgba (renderer->cr,
                             renderer->dia->bg_color.red, 
                             renderer->dia->bg_color.green, 
                             renderer->dia->bg_color.blue,
                             1.0);
    }
  cairo_paint (renderer->cr);
  if (renderer->with_alpha)
    {
      /* restore to default drawing */
      cairo_set_operator (renderer->cr, CAIRO_OPERATOR_OVER);
      cairo_set_source_rgba (renderer->cr,
                             renderer->dia->bg_color.red, 
                             renderer->dia->bg_color.green, 
                             renderer->dia->bg_color.blue,
                             1.0);
    }
#ifdef HAVE_PANGOCAIRO_H
  if (!renderer->layout)
    renderer->layout = pango_cairo_create_layout (renderer->cr);
#endif

  cairo_set_fill_rule (renderer->cr, CAIRO_FILL_RULE_EVEN_ODD);

#if 0 /* try to work around bug #341481 - no luck */
  {
    cairo_font_options_t *fo = cairo_font_options_create ();
    cairo_get_font_options (renderer->cr, fo);
    /* try to switch off kerning */
    cairo_font_options_set_hint_style (fo, CAIRO_HINT_STYLE_NONE);
    cairo_font_options_set_hint_metrics (fo, CAIRO_HINT_METRICS_OFF);

    cairo_set_font_options (renderer->cr, fo);
    cairo_font_options_destroy (fo);
#ifdef HAVE_PANGOCAIRO_H
    pango_cairo_update_context (renderer->cr, pango_layout_get_context (renderer->layout));
//.........这里部分代码省略.........

void MediaPlayerPrivate::paint(GraphicsContext* context, const IntRect& rect)
{
    if (context->paintingDisabled())
        return;

    if (!m_visible)
        return;
    if (!m_buffer)
        return;

    int width = 0, height = 0;
    int pixelAspectRatioNumerator = 0;
    int pixelAspectRatioDenominator = 0;
    double doublePixelAspectRatioNumerator = 0;
    double doublePixelAspectRatioDenominator = 0;
    double displayWidth;
    double displayHeight;
    double scale, gapHeight, gapWidth;

    GstCaps *caps = gst_buffer_get_caps(m_buffer);

    if (!gst_video_format_parse_caps(caps, NULL, &width, &height) ||
        !gst_video_parse_caps_pixel_aspect_ratio(caps, &pixelAspectRatioNumerator, &pixelAspectRatioDenominator)) {
      gst_caps_unref(caps);
      return;
    }

    displayWidth = width;
    displayHeight = height;
    doublePixelAspectRatioNumerator = pixelAspectRatioNumerator;
    doublePixelAspectRatioDenominator = pixelAspectRatioDenominator;

    cairo_t* cr = context->platformContext();
    cairo_surface_t* src = cairo_image_surface_create_for_data(GST_BUFFER_DATA(m_buffer),
                                                               CAIRO_FORMAT_RGB24,
                                                               width, height,
                                                               4 * width);

    cairo_save(cr);
    cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);

    displayWidth *= doublePixelAspectRatioNumerator / doublePixelAspectRatioDenominator;
    displayHeight *= doublePixelAspectRatioDenominator / doublePixelAspectRatioNumerator;

    scale = MIN (rect.width () / displayWidth, rect.height () / displayHeight);
    displayWidth *= scale;
    displayHeight *= scale;

    // Calculate gap between border an picture
    gapWidth = (rect.width() - displayWidth) / 2.0;
    gapHeight = (rect.height() - displayHeight) / 2.0;

    // paint the rectangle on the context and draw the surface inside.
    cairo_translate(cr, rect.x() + gapWidth, rect.y() + gapHeight);
    cairo_rectangle(cr, 0, 0, rect.width(), rect.height());
    cairo_scale(cr, doublePixelAspectRatioNumerator / doublePixelAspectRatioDenominator,
                doublePixelAspectRatioDenominator / doublePixelAspectRatioNumerator);
    cairo_scale(cr, scale, scale);
    cairo_set_source_surface(cr, src, 0, 0);
    cairo_fill(cr);
    cairo_restore(cr);

    cairo_surface_destroy(src);
    gst_caps_unref(caps);
}