[librsvg] ViewParams: Use accessor functions; make fields private

[Federico Mena Quintero <federico src gnome org>]

commit 4706d60727842f1d988309808b063909ae59f7c9
Author: Federico Mena Quintero <federico gnome org>
Date:   Tue Sep 4 15:08:12 2018 -0500

    ViewParams: Use accessor functions; make fields private

 rsvg_internals/src/drawing_ctx.rs | 39 +++++++++++++++++++++++++++++++++----
 rsvg_internals/src/length.rs      | 41 +++++++++++----------------------------
 2 files changed, 46 insertions(+), 34 deletions(-)
---
diff --git a/rsvg_internals/src/drawing_ctx.rs b/rsvg_internals/src/drawing_ctx.rs
index c58b9534..ff928318 100644
--- a/rsvg_internals/src/drawing_ctx.rs
+++ b/rsvg_internals/src/drawing_ctx.rs
@@ -40,11 +40,42 @@ use unitinterval::UnitInterval;
 use viewbox::ViewBox;
 
 /// Holds values that are required to normalize `Length` values to a current viewport.
+///
+/// This struct is created by calling `DrawingCtx::push_view_box()` or
+/// `DrawingCtx::get_view_params()`.
 pub struct ViewParams {
-    pub dpi_x: f64,
-    pub dpi_y: f64,
-    pub view_box_width: f64,
-    pub view_box_height: f64,
+    dpi_x: f64,
+    dpi_y: f64,
+    view_box_width: f64,
+    view_box_height: f64,
+}
+
+impl ViewParams {
+    #[cfg(test)]
+    pub fn new(dpi_x: f64, dpi_y: f64, view_box_width: f64, view_box_height: f64) -> ViewParams {
+        ViewParams {
+            dpi_x,
+            dpi_y,
+            view_box_width,
+            view_box_height,
+        }
+    }
+
+    pub fn dpi_x(&self) -> f64 {
+        self.dpi_x
+    }
+
+    pub fn dpi_y(&self) -> f64 {
+        self.dpi_y
+    }
+
+    pub fn view_box_width(&self) -> f64 {
+        self.view_box_width
+    }
+
+    pub fn view_box_height(&self) -> f64 {
+        self.view_box_height
+    }
 }
 
 pub enum RsvgDrawingCtx {}
diff --git a/rsvg_internals/src/length.rs b/rsvg_internals/src/length.rs
index 6a461f92..14b1c6da 100644
--- a/rsvg_internals/src/length.rs
+++ b/rsvg_internals/src/length.rs
@@ -99,10 +99,11 @@ impl Length {
             LengthUnit::Default => self.length,
 
             LengthUnit::Percent => match self.dir {
-                LengthDir::Horizontal => self.length * params.view_box_width,
-                LengthDir::Vertical => self.length * params.view_box_height,
+                LengthDir::Horizontal => self.length * params.view_box_width(),
+                LengthDir::Vertical => self.length * params.view_box_height(),
                 LengthDir::Both => {
-                    self.length * viewport_percentage(params.view_box_width, params.view_box_height)
+                    self.length
+                        * viewport_percentage(params.view_box_width(), params.view_box_height())
                 }
             },
 
@@ -225,9 +226,9 @@ impl Length {
 
 fn font_size_from_inch(length: f64, dir: LengthDir, params: &ViewParams) -> f64 {
     match dir {
-        LengthDir::Horizontal => length * params.dpi_x,
-        LengthDir::Vertical => length * params.dpi_y,
-        LengthDir::Both => length * viewport_percentage(params.dpi_x, params.dpi_y),
+        LengthDir::Horizontal => length * params.dpi_x(),
+        LengthDir::Vertical => length * params.dpi_y(),
+        LengthDir::Both => length * viewport_percentage(params.dpi_x(), params.dpi_y()),
     }
 }
 
@@ -405,12 +406,7 @@ mod tests {
 
     #[test]
     fn normalize_default_works() {
-        let params = ViewParams {
-            dpi_x: 40.0,
-            dpi_y: 40.0,
-            view_box_width: 100.0,
-            view_box_height: 100.0,
-        };
+        let params = ViewParams::new(40.0, 40.0, 100.0, 100.0);
 
         let values = ComputedValues::default();
 
@@ -422,12 +418,7 @@ mod tests {
 
     #[test]
     fn normalize_absolute_units_works() {
-        let params = ViewParams {
-            dpi_x: 40.0,
-            dpi_y: 50.0,
-            view_box_width: 100.0,
-            view_box_height: 100.0,
-        };
+        let params = ViewParams::new(40.0, 50.0, 100.0, 100.0);
 
         let values = ComputedValues::default();
 
@@ -443,12 +434,7 @@ mod tests {
 
     #[test]
     fn normalize_percent_works() {
-        let params = ViewParams {
-            dpi_x: 40.0,
-            dpi_y: 40.0,
-            view_box_width: 100.0,
-            view_box_height: 200.0,
-        };
+        let params = ViewParams::new(40.0, 40.0, 100.0, 200.0);
 
         let values = ComputedValues::default();
 
@@ -465,12 +451,7 @@ mod tests {
 
     #[test]
     fn normalize_font_em_ex_works() {
-        let params = ViewParams {
-            dpi_x: 40.0,
-            dpi_y: 40.0,
-            view_box_width: 100.0,
-            view_box_height: 200.0,
-        };
+        let params = ViewParams::new(40.0, 40.0, 100.0, 200.0);
 
         let values = ComputedValues::default();