[librsvg/wip/dimensions-api: 10/11] Svg::get_intrinsic_dimensions(): New method

[Federico Mena Quintero <federico src gnome org>]

commit 8afbe0d493062483d905f52e0e8a42a6eb0d46aa
Author: Federico Mena Quintero <federico gnome org>
Date:   Thu Feb 7 18:00:25 2019 -0600

    Svg::get_intrinsic_dimensions(): New method

 rsvg_internals/src/structure.rs | 18 ++++++++++++++++++
 rsvg_internals/src/svg.rs       | 11 ++++++++++-
 2 files changed, 28 insertions(+), 1 deletion(-)
---
diff --git a/rsvg_internals/src/structure.rs b/rsvg_internals/src/structure.rs
index 04fb6e3b..ba2205d8 100644
--- a/rsvg_internals/src/structure.rs
+++ b/rsvg_internals/src/structure.rs
@@ -95,6 +95,14 @@ impl NodeTrait for NodeSwitch {
     }
 }
 
+/// Intrinsic dimensions of an SVG document fragment
+#[derive(Copy, Clone)]
+pub struct IntrinsicDimensions {
+    width: Option<LengthHorizontal>,
+    height: Option<LengthVertical>,
+    vbox: Option<ViewBox>,
+}
+
 pub struct NodeSvg {
     preserve_aspect_ratio: Cell<AspectRatio>,
     x: Cell<LengthHorizontal>,
@@ -140,6 +148,16 @@ impl NodeSvg {
             (_, _, _) => None,
         }
     }
+
+    pub fn get_intrinsic_dimensions(&self) -> IntrinsicDimensions {
+        // FIXME: width/height are Option<>, and we don't store that yet;
+        // we resolve to 100% for default values at parsing time.
+        IntrinsicDimensions {
+            width: Some(self.w.get()),
+            height: Some(self.h.get()),
+            vbox: self.vbox.get(),
+        }
+    }
 }
 
 impl NodeTrait for NodeSvg {
diff --git a/rsvg_internals/src/svg.rs b/rsvg_internals/src/svg.rs
index dc75d9d5..45caad2b 100644
--- a/rsvg_internals/src/svg.rs
+++ b/rsvg_internals/src/svg.rs
@@ -11,8 +11,9 @@ use allowed_url::{AllowedUrl, Fragment};
 use error::LoadingError;
 use handle::LoadOptions;
 use io;
-use node::RsvgNode;
+use node::{NodeType, RsvgNode};
 use properties::ComputedValues;
+use structure::{IntrinsicDimensions, NodeSvg};
 use surface_utils::shared_surface::SharedImageSurface;
 use xml::XmlState;
 use xml2_load::xml_state_load_from_possibly_compressed_stream;
@@ -85,6 +86,14 @@ impl Svg {
     pub fn lookup_image(&self, href: &str) -> Result<SharedImageSurface, LoadingError> {
         self.images.borrow_mut().lookup(&self.load_options, href)
     }
+
+    pub fn get_intrinsic_dimensions(&self) -> IntrinsicDimensions {
+        let root = self.root();
+
+        assert!(root.get_type() == NodeType::Svg);
+
+        root.with_impl(|svg: &NodeSvg| svg.get_intrinsic_dimensions())
+    }
 }
 
 struct Resources {