Introduce a new compositor architecture

Having spent the last dev cycle looking at how we could specialize the
compositors for various backends, we once again look for the
commonalities in order to reduce the duplication. In part this is
motivated by the idea that spans is a good interface for both the
existent GL backend and pixman, and so they deserve a dedicated
compositor. xcb/xlib target an identical rendering system and so they
should be using the same compositor, and it should be possible to run
that same compositor locally against pixman to generate reference tests.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

P.S. This brings massive upheaval (read breakage) I've tried delaying in
order to fix as many things as possible but now this one patch does far,
far, far too much. Apologies in advance for breaking your favourite
backend, but trust me in that the end result will be much better. :)

1 files changed, 10 insertions, 32 deletions

diff --git a/src/cairo-clip-boxes.c b/src/cairo-clip-boxes.c
index e18c2f8ed..3b8265b9c 100644
--- a/src/cairo-clip-boxes.c
+++ b/src/cairo-clip-boxes.c
@@ -40,6 +40,8 @@
  */
 
 #include "cairoint.h"
+
+#include "cairo-box-private.h"
 #include "cairo-clip-private.h"
 #include "cairo-error-private.h"
 #include "cairo-freed-pool-private.h"
@@ -62,7 +64,6 @@ pot (int v)
     return v;
 }
 
-
 static cairo_bool_t
 _cairo_clip_contains_rectangle_box (const cairo_clip_t *clip,
 				    const cairo_rectangle_int_t *rect,
@@ -90,7 +91,6 @@ _cairo_clip_contains_rectangle_box (const cairo_clip_t *clip,
     }
 
     /* Check for a clip-box that wholly contains the rectangle */
-    assert (clip->num_boxes);
     for (i = 0; i < clip->num_boxes; i++) {
 	if (box->p1.x >= clip->boxes[i].p1.x &&
 	    box->p1.y >= clip->boxes[i].p1.y &&
@@ -176,6 +176,8 @@ _cairo_clip_intersect_rectangle_box (cairo_clip_t *clip,
 	    if (! _cairo_rectangle_intersect (&clip->extents, r))
 		clip = _cairo_clip_set_all_clipped (clip);
 	}
+	if (clip->path == NULL)
+	    clip->is_region = _cairo_box_is_pixel_aligned (box);
 	return clip;
     }
 
@@ -269,6 +271,7 @@ _cairo_clip_intersect_boxes (cairo_clip_t *clip,
 			     const cairo_boxes_t *boxes)
 {
     cairo_boxes_t clip_boxes;
+    cairo_box_t limits;
     cairo_rectangle_int_t extents;
 
     if (_cairo_clip_is_all_clipped (clip))
@@ -301,10 +304,11 @@ _cairo_clip_intersect_boxes (cairo_clip_t *clip,
     } else {
 	clip->boxes = _cairo_boxes_to_array (boxes, &clip->num_boxes, TRUE);
     }
-    _cairo_boxes_extents (boxes, &extents);
+    _cairo_boxes_extents (boxes, &limits);
     if (boxes == &clip_boxes)
 	_cairo_boxes_fini (&clip_boxes);
 
+    _cairo_box_round_to_rectangle (&limits, &extents);
     if (clip->path == NULL)
 	clip->extents = extents;
     else if (! _cairo_rectangle_intersect (&clip->extents, &extents))
@@ -557,37 +561,10 @@ _cairo_clip_reduce_for_composite (const cairo_clip_t *clip,
     return _cairo_clip_reduce_to_rectangle (clip, r);
 }
 
-cairo_status_t
-_cairo_clip_to_boxes (cairo_clip_t *clip,
-		      cairo_boxes_t *boxes)
-{
-    _cairo_boxes_init_for_array (boxes, clip->boxes, clip->num_boxes);
-
-    if (clip->path == NULL) {
-	cairo_box_t *src = clip->boxes;
-	int i;
-
-	clip->boxes = _cairo_malloc_ab (clip->num_boxes, sizeof (cairo_box_t));
-	if (clip->boxes == NULL) {
-	    clip->boxes = src;
-	    return _cairo_error (CAIRO_STATUS_NO_MEMORY);
-	}
-
-	for (i = 0; i < clip->num_boxes; i++) {
-	    clip->boxes[i].p1.x = _cairo_fixed_floor (src[i].p1.x);
-	    clip->boxes[i].p1.y = _cairo_fixed_floor (src[i].p1.y);
-	    clip->boxes[i].p2.x = _cairo_fixed_ceil (src[i].p2.x);
-	    clip->boxes[i].p2.y = _cairo_fixed_ceil (src[i].p2.y);
-	}
-    }
-
-    return CAIRO_STATUS_SUCCESS;
-
-}
-
 cairo_clip_t *
 _cairo_clip_from_boxes (const cairo_boxes_t *boxes)
 {
+    cairo_box_t extents;
     cairo_clip_t *clip = _cairo_clip_create ();
     if (clip == NULL)
 	return _cairo_clip_set_all_clipped (clip);
@@ -603,7 +580,8 @@ _cairo_clip_from_boxes (const cairo_boxes_t *boxes)
 	    return _cairo_clip_set_all_clipped (clip);
     }
 
-    _cairo_boxes_extents (boxes, &clip->extents);
+    _cairo_boxes_extents (boxes, &extents);
+    _cairo_box_round_to_rectangle (&extents, &clip->extents);
 
     return clip;
 }