quartz: Move drawing state out of surface

Some pattern types (gradients, surface patterns) require some
temporary information to be stored as "graphic state", because it
doesn't belong to CGContext. Previously all of this data was stored
inside the surface during the drawing operations, now it's in a
stack-allocated structure (of type cairo_quartz_drawing_state_t).
Based on a patch by Robert O'Callahan <robert@ocallahan.org>.
See https://bugzilla.mozilla.org/show_bug.cgi?id=522859

1 files changed, 95 insertions, 71 deletions

diff --git a/src/cairo-quartz-surface.c b/src/cairo-quartz-surface.c
index ec5aa267..6872e529 100644
--- a/src/cairo-quartz-surface.c
+++ b/src/cairo-quartz-surface.c
@@ -1304,6 +1304,23 @@ _cairo_quartz_cairo_repeating_surface_pattern_to_quartz (cairo_quartz_surface_t
     return CAIRO_STATUS_SUCCESS;
 }
 
+/* State used during a drawing operation. */
+typedef struct {
+    cairo_quartz_action_t action;
+
+    /* Used with DO_SHADING, DO_IMAGE and DO_TILED_IMAGE */
+    CGAffineTransform transform;
+
+    /* Used with DO_IMAGE and DO_TILED_IMAGE */
+    CGImageRef image;
+    cairo_surface_t *imageSurface;
+    CGRect imageRect;
+
+    /* Used with DO_SHADING */
+    CGShadingRef shading;
+
+} cairo_quartz_drawing_state_t;
+
 /*
 Quartz does not support repeating radients. We handle repeating gradients
 by manually extending the gradient and repeating color stops. We need to
@@ -1318,7 +1335,8 @@ we don't want the rasterization of the entire gradient to depend on the
 clip region).
 */
 static cairo_int_status_t
-_cairo_quartz_setup_linear_source (cairo_quartz_surface_t *surface,
+_cairo_quartz_setup_linear_source (cairo_quartz_drawing_state_t *state,
+				   cairo_quartz_surface_t *surface,
 				   const cairo_linear_pattern_t *lpat,
 				   const cairo_rectangle_int_t *extents)
 {
@@ -1333,7 +1351,7 @@ _cairo_quartz_setup_linear_source (cairo_quartz_surface_t *surface,
 
     mat = abspat->matrix;
     cairo_matrix_invert (&mat);
-    _cairo_quartz_cairo_matrix_to_quartz (&mat, &surface->sourceTransform);
+    _cairo_quartz_cairo_matrix_to_quartz (&mat, &state->transform);
 
     rgb = CGColorSpaceCreateDeviceRGB ();
 
@@ -1350,20 +1368,21 @@ _cairo_quartz_setup_linear_source (cairo_quartz_surface_t *surface,
 						          &start, &end,
 						          extents);
 
-    surface->sourceShading = CGShadingCreateAxial (rgb,
-						   start, end,
-						   gradFunc,
-						   extend, extend);
+    state->shading = CGShadingCreateAxial (rgb,
+					   start, end,
+					   gradFunc,
+					   extend, extend);
 
     CGColorSpaceRelease (rgb);
     CGFunctionRelease (gradFunc);
 
-    surface->action = DO_SHADING;
+    state->action = DO_SHADING;
     return CAIRO_STATUS_SUCCESS;
 }
 
 static cairo_int_status_t
-_cairo_quartz_setup_radial_source (cairo_quartz_surface_t *surface,
+_cairo_quartz_setup_radial_source (cairo_quartz_drawing_state_t *state,
+				   cairo_quartz_surface_t *surface,
 				   const cairo_radial_pattern_t *rpat,
 				   const cairo_rectangle_int_t *extents)
 {
@@ -1384,7 +1403,7 @@ _cairo_quartz_setup_radial_source (cairo_quartz_surface_t *surface,
 
     mat = abspat->matrix;
     cairo_matrix_invert (&mat);
-    _cairo_quartz_cairo_matrix_to_quartz (&mat, &surface->sourceTransform);
+    _cairo_quartz_cairo_matrix_to_quartz (&mat, &state->transform);
 
     rgb = CGColorSpaceCreateDeviceRGB ();
 
@@ -1400,30 +1419,33 @@ _cairo_quartz_setup_radial_source (cairo_quartz_surface_t *surface,
 						          &end, &r2,
 						          extents);
 
-    surface->sourceShading = CGShadingCreateRadial (rgb,
-						    start,
-						    r1,
-						    end,
-						    r2,
-						    gradFunc,
-						    extend, extend);
+    state->shading = CGShadingCreateRadial (rgb,
+					    start,
+					    r1,
+					    end,
+					    r2,
+					    gradFunc,
+					    extend, extend);
 
     CGColorSpaceRelease (rgb);
     CGFunctionRelease (gradFunc);
 
-    surface->action = DO_SHADING;
+    state->action = DO_SHADING;
     return CAIRO_STATUS_SUCCESS;
 }
 
 static cairo_int_status_t
-_cairo_quartz_setup_source (cairo_quartz_surface_t *surface,
+_cairo_quartz_setup_source (cairo_quartz_drawing_state_t *state,
+			    cairo_quartz_surface_t *surface,
 			    cairo_operator_t op,
 			    const cairo_pattern_t *source,
 			    const cairo_rectangle_int_t *extents)
 {
     cairo_status_t status;
 
-    assert (!(surface->sourceImage || surface->sourceShading));
+    state->image = NULL;
+    state->imageSurface = NULL;
+    state->shading = NULL;
 
     /* Save before we change the pattern, colorspace, etc. so that
      * we can restore and make sure that quartz releases our
@@ -1452,18 +1474,18 @@ _cairo_quartz_setup_source (cairo_quartz_surface_t *surface,
 				  solid->color.blue,
 				  solid->color.alpha);
 
-	surface->action = DO_DIRECT;
+	state->action = DO_DIRECT;
 	return CAIRO_STATUS_SUCCESS;
     }
 
     if (source->type == CAIRO_PATTERN_TYPE_LINEAR) {
 	const cairo_linear_pattern_t *lpat = (const cairo_linear_pattern_t *)source;
-	return _cairo_quartz_setup_linear_source (surface, lpat, extents);
+	return _cairo_quartz_setup_linear_source (state, surface, lpat, extents);
     }
 
     if (source->type == CAIRO_PATTERN_TYPE_RADIAL) {
 	const cairo_radial_pattern_t *rpat = (const cairo_radial_pattern_t *)source;
-	return _cairo_quartz_setup_radial_source (surface, rpat, extents);
+	return _cairo_quartz_setup_radial_source (state, surface, rpat, extents);
     }
 
     if (source->type == CAIRO_PATTERN_TYPE_SURFACE &&
@@ -1487,17 +1509,17 @@ _cairo_quartz_setup_source (cairo_quartz_surface_t *surface,
 
 	CGContextSetRGBFillColor (surface->cgContext, 0, 0, 0, 1);
 
-	surface->sourceImage = img;
+	state->image = img;
 
 	cairo_matrix_invert (&m);
-	_cairo_quartz_cairo_matrix_to_quartz (&m, &surface->sourceTransform);
+	_cairo_quartz_cairo_matrix_to_quartz (&m, &state->transform);
 
 	is_bounded = _cairo_surface_get_extents (pat_surf, &extents);
 	assert (is_bounded);
 
 	if (source->extend == CAIRO_EXTEND_NONE) {
-	    surface->sourceImageRect = CGRectMake (0, 0, extents.width, extents.height);
-	    surface->action = DO_IMAGE;
+	    state->imageRect = CGRectMake (0, 0, extents.width, extents.height);
+	    state->action = DO_IMAGE;
 	    return CAIRO_STATUS_SUCCESS;
 	}
 
@@ -1509,7 +1531,7 @@ _cairo_quartz_setup_source (cairo_quartz_surface_t *surface,
 	 */
 
 	xform = CGAffineTransformConcat (CGContextGetCTM (surface->cgContext),
-					 surface->sourceTransform);
+					 state->transform);
 
 	srcRect = CGRectMake (0, 0, extents.width, extents.height);
 	srcRect = CGRectApplyAffineTransform (srcRect, xform);
@@ -1530,8 +1552,8 @@ _cairo_quartz_setup_source (cairo_quartz_surface_t *surface,
 
 	    srcRect = CGRectApplyAffineTransform (srcRect, xform);
 
-	    surface->sourceImageRect = srcRect;
-	    surface->action = DO_TILED_IMAGE;
+	    state->imageRect = srcRect;
+	    state->action = DO_TILED_IMAGE;
 	    return CAIRO_STATUS_SUCCESS;
 	}
 
@@ -1563,7 +1585,7 @@ _cairo_quartz_setup_source (cairo_quartz_surface_t *surface,
 
 	CGPatternRelease (pattern);
 
-	surface->action = DO_DIRECT;
+	state->action = DO_DIRECT;
 	return CAIRO_STATUS_SUCCESS;
     }
 
@@ -1571,64 +1593,62 @@ _cairo_quartz_setup_source (cairo_quartz_surface_t *surface,
 }
 
 static void
-_cairo_quartz_teardown_source (cairo_quartz_surface_t *surface,
-			       const cairo_pattern_t *source)
+_cairo_quartz_teardown_source (cairo_quartz_drawing_state_t *state,
+			       cairo_quartz_surface_t *surface)
+			       
 {
     CGContextRestoreGState (surface->cgContext);
 
-    if (surface->sourceImage) {
-	CGImageRelease (surface->sourceImage);
-	surface->sourceImage = NULL;
+    if (state->image)
+	CGImageRelease (state->image);
 
-	cairo_surface_destroy (surface->sourceImageSurface);
-	surface->sourceImageSurface = NULL;
-    }
+    if (state->imageSurface)
+	cairo_surface_destroy (state->imageSurface);
 
-    if (surface->sourceShading) {
-	CGShadingRelease (surface->sourceShading);
-	surface->sourceShading = NULL;
-    }
+    if (state->shading)
+	CGShadingRelease (state->shading);
 }
 
 static cairo_int_status_t
-_cairo_quartz_setup_source_safe (cairo_quartz_surface_t *surface,
+_cairo_quartz_setup_source_safe (cairo_quartz_drawing_state_t *state,
+				 cairo_quartz_surface_t *surface,
 				 cairo_operator_t op,
 				 const cairo_pattern_t *source,
 				 const cairo_rectangle_int_t *extents)
 {
     cairo_int_status_t status;
 
-    status = _cairo_quartz_setup_source (surface, op, source, extents);
+    status = _cairo_quartz_setup_source (state, surface, op, source, extents);
     if (unlikely (status))
-	_cairo_quartz_teardown_source (surface, source);
+	_cairo_quartz_teardown_source (state, surface);
 
     return status;
 }
 
 static void
-_cairo_quartz_draw_source (cairo_quartz_surface_t *surface, cairo_operator_t op)
+_cairo_quartz_draw_source (cairo_quartz_surface_t *surface, cairo_operator_t op, cairo_quartz_drawing_state_t *state)
 {
-    CGContextConcatCTM (surface->cgContext, surface->sourceTransform);
+    CGContextConcatCTM (surface->cgContext, state->transform);
 
-    if (surface->action == DO_SHADING) {
-	CGContextDrawShading (surface->cgContext, surface->sourceShading);
+    if (state->action == DO_SHADING) {
+	CGContextDrawShading (surface->cgContext, state->shading);
 	return;
     }
 
-    CGContextTranslateCTM (surface->cgContext, 0, surface->sourceImageRect.size.height);
+    CGContextTranslateCTM (surface->cgContext, 0, state->imageRect.size.height);
     CGContextScaleCTM (surface->cgContext, 1, -1);
 
-    if (surface->action == DO_IMAGE) {
-	CGContextDrawImage (surface->cgContext, surface->sourceImageRect, surface->sourceImage);
+    if (state->action == DO_IMAGE) {
+	CGContextDrawImage (surface->cgContext, state->imageRect, state->image);
 	if (!_cairo_operator_bounded_by_source (op)) {
 	    CGContextBeginPath (surface->cgContext);
-	    CGContextAddRect (surface->cgContext, surface->sourceImageRect);
+	    CGContextAddRect (surface->cgContext, state->imageRect);
 	    CGContextAddRect (surface->cgContext, CGContextGetClipBoundingBox (surface->cgContext));
 	    CGContextSetRGBFillColor (surface->cgContext, 0, 0, 0, 0);
 	    CGContextEOFillPath (surface->cgContext);
 	}
     } else
-	CGContextDrawTiledImagePtr (surface->cgContext, surface->sourceImageRect, surface->sourceImage);
+	CGContextDrawTiledImagePtr (surface->cgContext, state->imageRect, state->image);
 }
 
 
@@ -1979,6 +1999,7 @@ _cairo_quartz_surface_paint_cg (cairo_quartz_surface_t *surface,
 				const cairo_pattern_t *source,
 				cairo_clip_t *clip)
 {
+    cairo_quartz_drawing_state_t state;
     cairo_int_status_t rv = CAIRO_STATUS_SUCCESS;
     cairo_rectangle_int_t extents;
 
@@ -1995,20 +2016,20 @@ _cairo_quartz_surface_paint_cg (cairo_quartz_surface_t *surface,
     extents.x -= surface->base.device_transform.x0;
     extents.y -= surface->base.device_transform.y0;
     _cairo_rectangle_union (&extents, &surface->extents);
-    rv = _cairo_quartz_setup_source_safe (surface, op, source, &extents);
+    rv = _cairo_quartz_setup_source_safe (&state, surface, op, source, &extents);
     if (unlikely (rv))
 	return rv;
 
-    if (surface->action == DO_DIRECT) {
+    if (state.action == DO_DIRECT) {
 	CGContextFillRect (surface->cgContext, CGRectMake (surface->extents.x,
 							   surface->extents.y,
 							   surface->extents.width,
 							   surface->extents.height));
     } else {
-	_cairo_quartz_draw_source (surface, op);
+	_cairo_quartz_draw_source (surface, op, &state);
     }
 
-    _cairo_quartz_teardown_source (surface, source);
+    _cairo_quartz_teardown_source (&state, surface);
 
     ND ((stderr, "-- paint\n"));
     return rv;
@@ -2051,6 +2072,7 @@ _cairo_quartz_surface_fill_cg (cairo_quartz_surface_t *surface,
 			       cairo_antialias_t antialias,
 			       cairo_clip_t *clip)
 {
+    cairo_quartz_drawing_state_t state;
     cairo_int_status_t rv = CAIRO_STATUS_SUCCESS;
     CGPathRef path_for_unbounded = NULL;
     cairo_rectangle_int_t extents;
@@ -2068,7 +2090,7 @@ _cairo_quartz_surface_fill_cg (cairo_quartz_surface_t *surface,
     extents.x -= surface->base.device_transform.x0;
     extents.y -= surface->base.device_transform.y0;
     _cairo_rectangle_union (&extents, &surface->extents);
-    rv = _cairo_quartz_setup_source_safe (surface, op, source, &extents);
+    rv = _cairo_quartz_setup_source_safe (&state, surface, op, source, &extents);
     if (unlikely (rv))
 	return rv;
 
@@ -2079,7 +2101,7 @@ _cairo_quartz_surface_fill_cg (cairo_quartz_surface_t *surface,
     if (!_cairo_operator_bounded_by_mask (op) && CGContextCopyPathPtr)
 	path_for_unbounded = CGContextCopyPathPtr (surface->cgContext);
 
-    if (surface->action == DO_DIRECT) {
+    if (state.action == DO_DIRECT) {
 	if (fill_rule == CAIRO_FILL_RULE_WINDING)
 	    CGContextFillPath (surface->cgContext);
 	else
@@ -2090,10 +2112,10 @@ _cairo_quartz_surface_fill_cg (cairo_quartz_surface_t *surface,
 	else
 	    CGContextEOClip (surface->cgContext);
 
-	_cairo_quartz_draw_source (surface, op);
+	_cairo_quartz_draw_source (surface, op, &state);
     }
 
-    _cairo_quartz_teardown_source (surface, source);
+    _cairo_quartz_teardown_source (&state, surface);
 
     if (path_for_unbounded) {
 	unbounded_op_data_t ub;
@@ -2158,6 +2180,7 @@ _cairo_quartz_surface_stroke_cg (cairo_quartz_surface_t *surface,
 				 cairo_antialias_t antialias,
 				 cairo_clip_t *clip)
 {
+    cairo_quartz_drawing_state_t state;
     cairo_int_status_t rv = CAIRO_STATUS_SUCCESS;
     CGAffineTransform origCTM, strokeTransform;
     CGPathRef path_for_unbounded = NULL;
@@ -2210,7 +2233,7 @@ _cairo_quartz_surface_stroke_cg (cairo_quartz_surface_t *surface,
     extents.x -= surface->base.device_transform.x0;
     extents.y -= surface->base.device_transform.y0;
     _cairo_rectangle_union (&extents, &surface->extents);
-    rv = _cairo_quartz_setup_source_safe (surface, op, source, &extents);
+    rv = _cairo_quartz_setup_source_safe (&state, surface, op, source, &extents);
     if (unlikely (rv))
 	return rv;
 
@@ -2222,17 +2245,17 @@ _cairo_quartz_surface_stroke_cg (cairo_quartz_surface_t *surface,
     _cairo_quartz_cairo_matrix_to_quartz (ctm, &strokeTransform);
     CGContextConcatCTM (surface->cgContext, strokeTransform);
 
-    if (surface->action == DO_DIRECT) {
+    if (state.action == DO_DIRECT) {
 	CGContextStrokePath (surface->cgContext);
     } else {
 	CGContextReplacePathWithStrokedPath (surface->cgContext);
 	CGContextClip (surface->cgContext);
 
 	CGContextSetCTM (surface->cgContext, origCTM);
-	_cairo_quartz_draw_source (surface, op);
+	_cairo_quartz_draw_source (surface, op, &state);
     }
 
-    _cairo_quartz_teardown_source (surface, source);
+    _cairo_quartz_teardown_source (&state, surface);
 
     if (path_for_unbounded) {
 	unbounded_op_data_t ub;
@@ -2312,6 +2335,7 @@ _cairo_quartz_surface_show_glyphs_cg (cairo_quartz_surface_t *surface,
     CGGlyph *cg_glyphs = &glyphs_static[0];
     CGSize *cg_advances = &cg_advances_static[0];
 
+    cairo_quartz_drawing_state_t state;
     cairo_rectangle_int_t extents;
     cairo_int_status_t rv = CAIRO_STATUS_SUCCESS;
     cairo_quartz_float_t xprev, yprev;
@@ -2338,11 +2362,11 @@ _cairo_quartz_surface_show_glyphs_cg (cairo_quartz_surface_t *surface,
     extents.x -= surface->base.device_transform.x0;
     extents.y -= surface->base.device_transform.y0;
     _cairo_rectangle_union (&extents, &surface->extents);
-    rv = _cairo_quartz_setup_source_safe (surface, op, source, &extents);
+    rv = _cairo_quartz_setup_source_safe (&state, surface, op, source, &extents);
     if (unlikely (rv))
 	return rv;
 
-    if (surface->action == DO_DIRECT) {
+    if (state.action == DO_DIRECT) {
 	CGContextSetTextDrawingMode (surface->cgContext, kCGTextFill);
     } else {
 	CGContextSetTextDrawingMode (surface->cgContext, kCGTextClip);
@@ -2428,11 +2452,11 @@ _cairo_quartz_surface_show_glyphs_cg (cairo_quartz_surface_t *surface,
 
     CGContextSetCTM (surface->cgContext, ctm);
 
-    if (surface->action != DO_DIRECT)
-	_cairo_quartz_draw_source (surface, op);
+    if (state.action != DO_DIRECT)
+	_cairo_quartz_draw_source (surface, op, &state);
 
 BAIL:
-    _cairo_quartz_teardown_source (surface, source);
+    _cairo_quartz_teardown_source (&state, surface);
 
     if (didForceFontSmoothing)
 	CGContextSetAllowsFontSmoothingPtr (surface->cgContext, FALSE);