[librsvg] Svg::lookup_image(): Return a SharedImageSurface

[Federico Mena Quintero <federico src gnome org>]

commit 0df760de48aafdeb869666b8ffa93656919bd491
Author: Federico Mena Quintero <federico gnome org>
Date:   Tue Jan 15 10:56:16 2019 -0600

    Svg::lookup_image(): Return a SharedImageSurface
    
    The idea is to keep only immutable surfaces around.  This adds a
    method SharedImageSurface::to_cairo_pattern(), since creating a
    pattern requires access to the inner surface.

 rsvg_internals/src/drawing_ctx.rs                  |  3 ++-
 rsvg_internals/src/filters/image.rs                | 12 ++++++------
 rsvg_internals/src/image.rs                        |  8 ++++----
 rsvg_internals/src/surface_utils/shared_surface.rs |  5 +++++
 rsvg_internals/src/svg.rs                          |  9 +++------
 5 files changed, 20 insertions(+), 17 deletions(-)
---
diff --git a/rsvg_internals/src/drawing_ctx.rs b/rsvg_internals/src/drawing_ctx.rs
index b961e5e6..1348fe04 100644
--- a/rsvg_internals/src/drawing_ctx.rs
+++ b/rsvg_internals/src/drawing_ctx.rs
@@ -29,6 +29,7 @@ use state::{
     StrokeLinecap,
     StrokeLinejoin,
 };
+use surface_utils::shared_surface::SharedImageSurface;
 use svg::Svg;
 use unit_interval::UnitInterval;
 use viewbox::ViewBox;
@@ -713,7 +714,7 @@ impl DrawingCtx {
         }
     }
 
-    pub fn lookup_image(&self, href: &str) -> Option<cairo::ImageSurface> {
+    pub fn lookup_image(&self, href: &str) -> Option<SharedImageSurface> {
         self.svg.lookup_image(href)
     }
 
diff --git a/rsvg_internals/src/filters/image.rs b/rsvg_internals/src/filters/image.rs
index 262cb866..3dda5c7b 100644
--- a/rsvg_internals/src/filters/image.rs
+++ b/rsvg_internals/src/filters/image.rs
@@ -139,8 +139,8 @@ impl Image {
         let render_bounds = bounds_builder.into_irect_without_clipping(draw_ctx);
         let aspect = self.aspect.get();
         let (x, y, w, h) = aspect.compute(
-            f64::from(surface.get_width()),
-            f64::from(surface.get_height()),
+            f64::from(surface.width()),
+            f64::from(surface.height()),
             f64::from(render_bounds.x0),
             f64::from(render_bounds.y0),
             f64::from(render_bounds.x1 - render_bounds.x0),
@@ -148,12 +148,12 @@ impl Image {
         );
 
         if w != 0f64 && h != 0f64 {
-            let ptn = cairo::SurfacePattern::create(&surface);
+            let ptn = surface.to_cairo_pattern();
             let mut matrix = cairo::Matrix::new(
-                w / f64::from(surface.get_width()),
+                w / f64::from(surface.width()),
                 0f64,
                 0f64,
-                h / f64::from(surface.get_height()),
+                h / f64::from(surface.height()),
                 x,
                 y,
             );
@@ -169,7 +169,7 @@ impl Image {
                 f64::from(bounds.y1 - bounds.y0),
             );
             cr.clip();
-            cr.set_source(&cairo::Pattern::SurfacePattern(ptn));
+            cr.set_source(&ptn);
             cr.paint();
         }
 
diff --git a/rsvg_internals/src/image.rs b/rsvg_internals/src/image.rs
index 74041e07..60fa18bd 100644
--- a/rsvg_internals/src/image.rs
+++ b/rsvg_internals/src/image.rs
@@ -108,8 +108,8 @@ impl NodeTrait for NodeImage {
                     dc.clip(x, y, w, h);
                 }
 
-                let width = surface.get_width();
-                let height = surface.get_height();
+                let width = surface.width();
+                let height = surface.height();
                 if clipping || width == 0 || height == 0 {
                     return Ok(());
                 }
@@ -146,12 +146,12 @@ impl NodeTrait for NodeImage {
                 // For example, in svg1.1/filters-blend-01-b.svgthere's a completely
                 // opaque 100×1 image of a gradient scaled to 100×98 which ends up
                 // transparent almost everywhere without this fix (which it shouldn't).
-                let ptn = cairo::SurfacePattern::create(&surface);
+                let ptn = surface.to_cairo_pattern();
                 let mut matrix = cairo::Matrix::identity();
                 matrix.translate(-x, -y);
                 ptn.set_matrix(matrix);
                 ptn.set_extend(cairo::Extend::Pad);
-                cr.set_source(&cairo::Pattern::SurfacePattern(ptn));
+                cr.set_source(&ptn);
 
                 // Clip is needed due to extend being set to pad.
                 cr.rectangle(x, y, width, height);
diff --git a/rsvg_internals/src/surface_utils/shared_surface.rs 
b/rsvg_internals/src/surface_utils/shared_surface.rs
index 05c6a57d..ad45c8fd 100644
--- a/rsvg_internals/src/surface_utils/shared_surface.rs
+++ b/rsvg_internals/src/surface_utils/shared_surface.rs
@@ -295,6 +295,11 @@ impl SharedImageSurface {
         cr.set_source_surface(&self.surface, x, y);
     }
 
+    /// Creates a Cairo surface pattern from the surface
+    pub fn to_cairo_pattern(&self) -> cairo::Pattern {
+        cairo::Pattern::SurfacePattern(cairo::SurfacePattern::create(&self.surface))
+    }
+
     /// Returns a new `ImageSurface` with the same contents as the one stored in this
     /// `SharedImageSurface` within the given bounds.
     pub fn copy_surface(&self, bounds: IRect) -> Result<ImageSurface, cairo::Status> {
diff --git a/rsvg_internals/src/svg.rs b/rsvg_internals/src/svg.rs
index 9d7abc11..a07222f0 100644
--- a/rsvg_internals/src/svg.rs
+++ b/rsvg_internals/src/svg.rs
@@ -1,4 +1,4 @@
-use cairo::{ImageSurface, Status};
+use cairo::Status;
 use gdk_pixbuf::{PixbufLoader, PixbufLoaderExt};
 use gio;
 use glib::translate::*;
@@ -81,11 +81,8 @@ impl Svg {
         self.ids.get(id).map(|n| (*n).clone())
     }
 
-    pub fn lookup_image(&self, href: &str) -> Option<ImageSurface> {
-        self.images
-            .borrow_mut()
-            .lookup(&self.load_options, href)
-            .and_then(|s| s.into_image_surface().ok())
+    pub fn lookup_image(&self, href: &str) -> Option<SharedImageSurface> {
+        self.images.borrow_mut().lookup(&self.load_options, href)
     }
 }