gfx/cairo/clip-rects-surface-extents.patch

   1 From 108b1c7825116ed3f93aa57384bbd3290cdc9181 Mon Sep 17 00:00:00 2001
   2 From: Karl Tomlinson <karlt+@karlt.net>
   3 Date: Sat, 17 Jul 2010 01:08:53 +0000
   4 Subject: clip: consider gstate target extents in _cairo_gstate_copy_clip_rectangle_list
   5
   6 Fixes https://bugs.freedesktop.org/show_bug.cgi?id=29125
   7
   8 To be consistent with _cairo_gstate_clip_extents, the context's clip
   9 should be intersected with the target surface extents (instead of only
  10 using them when there is no clip).
  11
  12 Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
  13 ---
  14 diff --git a/src/cairo-clip.c b/src/cairo-clip.c
  15 index 77d8214..d5a2fab 100644
  16 --- a/src/cairo-clip.c
  17 +++ b/src/cairo-clip.c
  18 @@ -1495,7 +1495,7 @@ _cairo_rectangle_list_create_in_error (cairo_status_t status)
  19  cairo_rectangle_list_t *
  20  _cairo_clip_copy_rectangle_list (cairo_clip_t *clip, cairo_gstate_t *gstate)
  21  {
  22 -#define ERROR_LIST(S) _cairo_rectangle_list_create_in_error (_cairo_error (S));
  23 +#define ERROR_LIST(S) _cairo_rectangle_list_create_in_error (_cairo_error (S))
  24
  25      cairo_rectangle_list_t *list;
  26      cairo_rectangle_t *rectangles = NULL;
  27 @@ -1507,57 +1507,37 @@ _cairo_clip_copy_rectangle_list (cairo_clip_t *clip, cairo_gstate_t *gstate)
  28      if (clip->all_clipped)
  29         goto DONE;
  30
  31 -    if (clip->path != NULL) {
  32 -       status = _cairo_clip_get_region (clip, &region);
  33 -       if (status == CAIRO_INT_STATUS_NOTHING_TO_DO) {
  34 -           goto DONE;
  35 -       } else if (status == CAIRO_INT_STATUS_UNSUPPORTED) {
  36 -           return ERROR_LIST (CAIRO_STATUS_CLIP_NOT_REPRESENTABLE)
  37 -       } else if (unlikely (status)) {
  38 -           return ERROR_LIST (status);
  39 -       }
  40 -    }
  41 -
  42 -    if (region != NULL) {
  43 -       n_rects = cairo_region_num_rectangles (region);
  44 -       if (n_rects) {
  45 -           rectangles = _cairo_malloc_ab (n_rects, sizeof (cairo_rectangle_t));
  46 -           if (unlikely (rectangles == NULL)) {
  47 -               return ERROR_LIST (CAIRO_STATUS_NO_MEMORY);
  48 -           }
  49 +    if (!clip->path)
  50 +       return ERROR_LIST (CAIRO_STATUS_CLIP_NOT_REPRESENTABLE);
  51
  52 -           for (i = 0; i < n_rects; ++i) {
  53 -               cairo_rectangle_int_t clip_rect;
  54 -
  55 -               cairo_region_get_rectangle (region, i, &clip_rect);
  56 +    status = _cairo_clip_get_region (clip, &region);
  57 +    if (status == CAIRO_INT_STATUS_NOTHING_TO_DO) {
  58 +       goto DONE;
  59 +    } else if (status == CAIRO_INT_STATUS_UNSUPPORTED) {
  60 +       return ERROR_LIST (CAIRO_STATUS_CLIP_NOT_REPRESENTABLE);
  61 +    } else if (unlikely (status)) {
  62 +       return ERROR_LIST (status);
  63 +    }
  64
  65 -               if (! _cairo_clip_int_rect_to_user (gstate,
  66 -                                                   &clip_rect,
  67 -                                                   &rectangles[i]))
  68 -               {
  69 -                   free (rectangles);
  70 -                   return ERROR_LIST (CAIRO_STATUS_CLIP_NOT_REPRESENTABLE);
  71 -               }
  72 -           }
  73 +    n_rects = cairo_region_num_rectangles (region);
  74 +    if (n_rects) {
  75 +       rectangles = _cairo_malloc_ab (n_rects, sizeof (cairo_rectangle_t));
  76 +       if (unlikely (rectangles == NULL)) {
  77 +           return ERROR_LIST (CAIRO_STATUS_NO_MEMORY);
  78         }
  79 -    } else {
  80 -        cairo_rectangle_int_t extents;
  81
  82 -       if (! _cairo_surface_get_extents (_cairo_gstate_get_target (gstate),
  83 -                                         &extents))
  84 -       {
  85 -           /* unbounded surface -> unclipped */
  86 -           goto DONE;
  87 -       }
  88 +       for (i = 0; i < n_rects; ++i) {
  89 +           cairo_rectangle_int_t clip_rect;
  90
  91 -       n_rects = 1;
  92 -       rectangles = malloc(sizeof (cairo_rectangle_t));
  93 -       if (unlikely (rectangles == NULL))
  94 -           return ERROR_LIST (CAIRO_STATUS_NO_MEMORY);
  95 +           cairo_region_get_rectangle (region, i, &clip_rect);
  96
  97 -       if (! _cairo_clip_int_rect_to_user (gstate, &extents, rectangles)) {
  98 -           free (rectangles);
  99 -           return ERROR_LIST (CAIRO_STATUS_CLIP_NOT_REPRESENTABLE);
 100 +           if (! _cairo_clip_int_rect_to_user (gstate,
 101 +                                               &clip_rect,
 102 +                                               &rectangles[i]))
 103 +           {
 104 +               free (rectangles);
 105 +               return ERROR_LIST (CAIRO_STATUS_CLIP_NOT_REPRESENTABLE);
 106 +           }
 107         }
 108      }
 109
 110 diff --git a/src/cairo-gstate.c b/src/cairo-gstate.c
 111 index baf6145..7caf624 100644
 112 --- a/src/cairo-gstate.c
 113 +++ b/src/cairo-gstate.c
 114 @@ -1555,7 +1555,19 @@ _cairo_gstate_clip_extents (cairo_gstate_t *gstate,
 115  cairo_rectangle_list_t*
 116  _cairo_gstate_copy_clip_rectangle_list (cairo_gstate_t *gstate)
 117  {
 118 -    return _cairo_clip_copy_rectangle_list (&gstate->clip, gstate);
 119 +    cairo_clip_t clip;
 120 +    cairo_rectangle_int_t extents;
 121 +    cairo_rectangle_list_t *list;
 122 +
 123 +    _cairo_clip_init_copy (&clip, &gstate->clip);
 124 +
 125 +    if (_cairo_surface_get_extents (gstate->target, &extents))
 126 +        _cairo_clip_rectangle (&clip, &extents);
 127 +
 128 +    list = _cairo_clip_copy_rectangle_list (&clip, gstate);
 129 +    _cairo_clip_fini (&clip);
 130 +
 131 +    return list;
 132  }
 133
 134  static void
 135 diff --git a/test/get-clip.c b/test/get-clip.c
 136 index f0477a1..f97db3f 100644
 137 --- a/test/get-clip.c
 138 +++ b/test/get-clip.c
 139 @@ -120,6 +120,22 @@ preamble (cairo_test_context_t *ctx)
 140      }
 141      cairo_rectangle_list_destroy (rectangle_list);
 142
 143 +    /* We should get the same results after applying a clip that contains the
 144 +       existing clip. */
 145 +    phase = "Clip beyond surface extents";
 146 +    cairo_save (cr);
 147 +    cairo_rectangle (cr, -10, -10, SIZE + 20 , SIZE + 20);
 148 +    cairo_clip (cr);
 149 +    rectangle_list = cairo_copy_clip_rectangle_list (cr);
 150 +    if (! check_count (ctx, phase, rectangle_list, 1) ||
 151 +        ! check_clip_extents (ctx, phase, cr, 0, 0, SIZE, SIZE) ||
 152 +        ! check_rectangles_contain (ctx, phase, rectangle_list, 0, 0, SIZE, SIZE))
 153 +    {
 154 +       goto FAIL;
 155 +    }
 156 +    cairo_rectangle_list_destroy (rectangle_list);
 157 +    cairo_restore (cr);
 158 +
 159      /* Test simple clip rect. */
 160      phase = "Simple clip rect";
 161      cairo_save (cr);
 162 --
 163 cgit v0.8.3-6-g21f6