Query the backend to see if we can repaint the solid pattern.

If we are dithering on the Xlib backend we can not simply repaint the
surface used for a solid pattern and must recreate it from scratch.
However, for ordinary XRender usage we do not want to have to pay that
price - so query the backend to see if we can reuse the surface.

src/cairo-analysis-surface.c

@@ -749,6 +749,7 @@ static const cairo_surface_backend_t cairo_analysis_surface_backend = {
     NULL, /* reset */
     NULL, /* fill_stroke */
     NULL, /* create_solid_pattern_surface */
+    NULL, /* can_repaint_solid_pattern_surface */
     _cairo_analysis_surface_has_show_text_glyphs,
     _cairo_analysis_surface_show_text_glyphs
 };
@@ -966,6 +967,7 @@ static const cairo_surface_backend_t cairo_null_surface_backend = {
     NULL, /* reset */
     NULL, /* fill_stroke */
     NULL, /* create_solid_pattern_surface */
+    NULL, /* can_repaint_solid_pattern_surface */
     NULL, /* has_show_text_glyphs */
     NULL  /* show_text_glyphs */
 };

src/cairo-meta-surface.c

@@ -678,6 +678,7 @@ static const cairo_surface_backend_t cairo_meta_surface_backend = {
     NULL, /* reset */
     NULL, /* fill_stroke */
     NULL, /* create_solid_pattern_surface */
+    NULL, /* can_repaint_solid_pattern_surface */
 
     _cairo_meta_surface_has_show_text_glyphs,
     _cairo_meta_surface_show_text_glyphs

src/cairo-paginated-surface.c

@@ -701,6 +701,7 @@ static const cairo_surface_backend_t cairo_paginated_surface_backend = {
     NULL, /* reset */
     NULL, /* fill_stroke */
     NULL, /* create_solid_pattern_surface */
+    NULL, /* can_repaint_solid_pattern_surface */
     _cairo_paginated_surface_has_show_text_glyphs,
     _cairo_paginated_surface_show_text_glyphs
 };

src/cairo-pdf-surface.c

@@ -5335,6 +5335,7 @@ static const cairo_surface_backend_t cairo_pdf_surface_backend = {
     NULL, /* reset */
     _cairo_pdf_surface_fill_stroke,
     NULL, /* create_solid_pattern_surface */
+    NULL, /* can_repaint_solid_pattern_surface */
     _cairo_pdf_surface_has_show_text_glyphs,
     _cairo_pdf_surface_show_text_glyphs,
 };

src/cairo-script-surface.c

@@ -2452,6 +2452,7 @@ _cairo_script_surface_backend = {
     NULL, /* reset */
     NULL, /* fill_stroke */
     NULL, /* create_solid_pattern_surface */
+    NULL, /* can_repaint_solid_pattern_surface */
 
     /* The alternate high-level text operation */
     _cairo_script_surface_has_show_text_glyphs,

src/cairo-surface.c

@@ -334,19 +334,19 @@ cairo_surface_t *
 _cairo_surface_create_solid_pattern_surface (cairo_surface_t	   *other,
 					     const cairo_solid_pattern_t *solid_pattern)
 {
-    cairo_surface_t *surface;
+    if (other->backend->create_solid_pattern_surface != NULL) {
+	cairo_surface_t *surface;
 
-    if (other->backend->create_solid_pattern_surface) {
-	surface = other->backend->create_solid_pattern_surface (other, solid_pattern);
+	surface = other->backend->create_solid_pattern_surface (other,
+								solid_pattern);
 	if (surface)
 	    return surface;
     }
 
-    surface = _cairo_surface_create_similar_solid (other,
-						   solid_pattern->content,
-						   1, 1,
-						   &solid_pattern->color);
-    return surface;
+    return _cairo_surface_create_similar_solid (other,
+						solid_pattern->content,
+						1, 1,
+						&solid_pattern->color);
 }
 
 cairo_int_status_t
@@ -354,17 +354,24 @@ _cairo_surface_repaint_solid_pattern_surface (cairo_surface_t	    *other,
 					      cairo_surface_t       *solid_surface,
 					      const cairo_solid_pattern_t *solid_pattern)
 {
-    if (other->backend->create_solid_pattern_surface)
-	/* Solid pattern surface for this backend are not trivial to make.
-	 * Skip repainting.
-	 *
-	 * This does not work optimally with things like analysis surface that
-	 * are proxies.  But returning UNSUPPORTED is *safe* as it only
-	 * disables some caching.
-	 */
+    /* Solid pattern surface for these backends are special and not trivial
+     * to repaint.  Skip repainting.
+     *
+     * This does not work optimally with things like analysis surface that
+     * are proxies.  But returning UNSUPPORTED is *safe* as it only
+     * disables some caching.
+     */
+    if (other->backend->create_solid_pattern_surface != NULL &&
+	! other->backend->can_repaint_solid_pattern_surface (solid_surface,
+							     solid_pattern))
+    {
 	return CAIRO_INT_STATUS_UNSUPPORTED;
+    }
 
-    return _cairo_surface_paint (solid_surface, CAIRO_OPERATOR_SOURCE, &solid_pattern->base, NULL);
+    return _cairo_surface_paint (solid_surface,
+				 CAIRO_OPERATOR_SOURCE,
+				 &solid_pattern->base,
+				 NULL);
 }
 
 cairo_clip_mode_t

src/cairo-xlib-surface.c

@@ -1310,6 +1310,15 @@ _cairo_xlib_surface_create_solid_pattern_surface (void                  *abstrac
     return &surface->base;
 }
 
+static cairo_bool_t
+_cairo_xlib_surface_can_repaint_solid_pattern_surface (void *abstract_surface,
+						       const cairo_solid_pattern_t *solid_pattern)
+{
+    cairo_xlib_surface_t *other = abstract_surface;
+    return CAIRO_SURFACE_RENDER_HAS_COMPOSITE (other);
+}
+
+
 static cairo_status_t
 _cairo_xlib_surface_set_matrix (cairo_xlib_surface_t *surface,
 				cairo_matrix_t	     *matrix,
@@ -2469,7 +2478,8 @@ static const cairo_surface_backend_t cairo_xlib_surface_backend = {
     _cairo_xlib_surface_is_similar,
     _cairo_xlib_surface_reset,
     NULL, /* fill_stroke */
-    _cairo_xlib_surface_create_solid_pattern_surface
+    _cairo_xlib_surface_create_solid_pattern_surface,
+    _cairo_xlib_surface_can_repaint_solid_pattern_surface
 };
 
 /**

src/cairoint.h

@@ -822,6 +822,11 @@ struct _cairo_surface_backend {
 			        (void			      *surface,
 				 const cairo_solid_pattern_t  *solid_pattern);
 
+    cairo_bool_t
+    (*can_repaint_solid_pattern_surface)
+			        (void			      *surface,
+				 const cairo_solid_pattern_t  *solid_pattern);
+
     cairo_bool_t
     (*has_show_text_glyphs)	(void			    *surface);
 

src/test-meta-surface.c

@@ -336,6 +336,7 @@ static const cairo_surface_backend_t test_meta_surface_backend = {
     NULL, /* reset */
     NULL, /* fill_stroke */
     NULL, /* create_solid_pattern_surface */
+    NULL, /* can_repaint_solid_pattern_surface */
     _test_meta_surface_has_show_text_glyphs,
     _test_meta_surface_show_text_glyphs
 };

src/test-paginated-surface.c

@@ -326,6 +326,7 @@ static const cairo_surface_backend_t test_paginated_surface_backend = {
     NULL, /* reset */
     NULL, /* fill_stroke */
     NULL, /* create_solid_pattern_surface */
+    NULL, /* can_repaint_solid_pattern_surface */
 
     _test_paginated_surface_has_show_text_glyphs,
     _test_paginated_surface_show_text_glyphs