Auto merge of #17180 - Manishearth:stylo-fill-stroke, r=birtles

stylo: Animate fill and stroke

r=birtles https://bugzilla.mozilla.org/show_bug.cgi?id=1369277

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3 files changed, 101 insertions, 2 deletions

diff --git a/components/style/properties/gecko.mako.rs b/components/style/properties/gecko.mako.rs
index 3328e682f1c..2186967279a 100644
--- a/components/style/properties/gecko.mako.rs
+++ b/components/style/properties/gecko.mako.rs
@@ -461,6 +461,35 @@ fn color_to_nscolor_zero_currentcolor(color: Color) -> structs::nscolor {
             );
         }
     }
+
+    #[allow(non_snake_case)]
+    pub fn clone_${ident}(&self) -> longhands::${ident}::computed_value::T {
+        use values::generics::{SVGPaint, SVGPaintKind};
+        use self::structs::nsStyleSVGPaintType;
+        use self::structs::nsStyleSVGFallbackType;
+        let ref paint = ${get_gecko_property(gecko_ffi_name)};
+        let fallback = if let nsStyleSVGFallbackType::eStyleSVGFallbackType_Color = paint.mFallbackType {
+            Some(Color::RGBA(convert_nscolor_to_rgba(paint.mFallbackColor)))
+        } else {
+            None
+        };
+        let kind = match paint.mType {
+            nsStyleSVGPaintType::eStyleSVGPaintType_None => SVGPaintKind::None,
+            nsStyleSVGPaintType::eStyleSVGPaintType_ContextFill => SVGPaintKind::ContextFill,
+            nsStyleSVGPaintType::eStyleSVGPaintType_ContextStroke => SVGPaintKind::ContextStroke,
+            nsStyleSVGPaintType::eStyleSVGPaintType_Server => {
+                // FIXME (bug 1353966) this should animate
+                SVGPaintKind::None
+            }
+            nsStyleSVGPaintType::eStyleSVGPaintType_Color => {
+                unsafe { SVGPaintKind::Color(Color::RGBA(convert_nscolor_to_rgba(*paint.mPaint.mColor.as_ref()))) }
+            }
+        };
+        SVGPaint {
+            kind: kind,
+            fallback: fallback,
+        }
+    }
 </%def>
 
 <%def name="impl_app_units(ident, gecko_ffi_name, need_clone, inherit_from=None, round_to_pixels=False)">
diff --git a/components/style/properties/helpers/animated_properties.mako.rs b/components/style/properties/helpers/animated_properties.mako.rs
index e76c0caabbb..f018967fb9a 100644
--- a/components/style/properties/helpers/animated_properties.mako.rs
+++ b/components/style/properties/helpers/animated_properties.mako.rs
@@ -42,6 +42,7 @@ use values::computed::{BorderCornerRadius, ClipRect};
 use values::computed::{CalcLengthOrPercentage, Context, LengthOrPercentage};
 use values::computed::{MaxLength, MozLength};
 use values::computed::ToComputedValue;
+use values::generics::{SVGPaint, SVGPaintKind};
 use values::generics::border::BorderCornerRadius as GenericBorderCornerRadius;
 use values::generics::position as generic_position;
 
@@ -2849,6 +2850,75 @@ impl From<IntermediateColor> for CSSParserColor {
     }
 }
 
+/// Animatable SVGPaint
+pub type IntermediateSVGPaint = SVGPaint<IntermediateColor>;
+/// Animatable SVGPaintKind
+pub type IntermediateSVGPaintKind = SVGPaintKind<IntermediateColor>;
+
+impl From<::values::computed::SVGPaint> for IntermediateSVGPaint {
+    fn from(paint: ::values::computed::SVGPaint) -> IntermediateSVGPaint {
+        paint.convert(|color| (*color).into())
+    }
+}
+
+impl From<IntermediateSVGPaint> for ::values::computed::SVGPaint {
+    fn from(paint: IntermediateSVGPaint) -> ::values::computed::SVGPaint {
+        paint.convert(|color| (*color).into())
+    }
+}
+
+
+impl Animatable for IntermediateSVGPaint {
+    #[inline]
+    fn add_weighted(&self, other: &Self, self_portion: f64, other_portion: f64) -> Result<Self, ()> {
+        Ok(IntermediateSVGPaint {
+            kind: self.kind.add_weighted(&other.kind, self_portion, other_portion)?,
+            fallback: self.fallback.add_weighted(&other.fallback, self_portion, other_portion)?,
+        })
+    }
+
+    #[inline]
+    fn compute_distance(&self, other: &Self) -> Result<f64, ()> {
+        self.compute_squared_distance(other).map(|sq| sq.sqrt())
+    }
+
+    #[inline]
+    fn compute_squared_distance(&self, other: &Self) -> Result<f64, ()> {
+        Ok(self.kind.compute_squared_distance(&other.kind)? +
+            self.fallback.compute_squared_distance(&other.fallback)?)
+    }
+}
+
+impl Animatable for IntermediateSVGPaintKind {
+    #[inline]
+    fn add_weighted(&self, other: &Self, self_portion: f64, other_portion: f64) -> Result<Self, ()> {
+        match (self, other) {
+            (&SVGPaintKind::Color(ref self_color), &SVGPaintKind::Color(ref other_color)) => {
+                Ok(SVGPaintKind::Color(self_color.add_weighted(other_color, self_portion, other_portion)?))
+            }
+            // FIXME context values should be interpolable with colors
+            // Gecko doesn't implement this behavior either.
+            (&SVGPaintKind::None, &SVGPaintKind::None) => Ok(SVGPaintKind::None),
+            (&SVGPaintKind::ContextFill, &SVGPaintKind::ContextFill) => Ok(SVGPaintKind::ContextFill),
+            (&SVGPaintKind::ContextStroke, &SVGPaintKind::ContextStroke) => Ok(SVGPaintKind::ContextStroke),
+            _ => Err(())
+        }
+    }
+
+    #[inline]
+    fn compute_distance(&self, other: &Self) -> Result<f64, ()> {
+        match (self, other) {
+            (&SVGPaintKind::Color(ref self_color), &SVGPaintKind::Color(ref other_color)) => {
+                self_color.compute_distance(other_color)
+            }
+            (&SVGPaintKind::None, &SVGPaintKind::None) |
+            (&SVGPaintKind::ContextFill, &SVGPaintKind::ContextFill) |
+            (&SVGPaintKind::ContextStroke, &SVGPaintKind::ContextStroke)=> Ok(0.0),
+            _ => Err(())
+        }
+    }
+}
+
 <%def name="impl_intermediate_type_for_shadow(type)">
     #[derive(Copy, Clone, Debug, PartialEq)]
     #[cfg_attr(feature = "servo", derive(HeapSizeOf))]
diff --git a/components/style/properties/longhand/inherited_svg.mako.rs b/components/style/properties/longhand/inherited_svg.mako.rs
index 2dfa696c2dc..4c57a13f43c 100644
--- a/components/style/properties/longhand/inherited_svg.mako.rs
+++ b/components/style/properties/longhand/inherited_svg.mako.rs
@@ -35,7 +35,7 @@ ${helpers.predefined_type(
     "fill", "SVGPaint",
     "::values::computed::SVGPaint::black()",
     products="gecko",
-    animation_value_type="none",
+    animation_value_type="IntermediateSVGPaint",
     boxed=True,
     spec="https://www.w3.org/TR/SVG2/painting.html#SpecifyingFillPaint")}
 
@@ -59,7 +59,7 @@ ${helpers.predefined_type(
     "stroke", "SVGPaint",
     "Default::default()",
     products="gecko",
-    animation_value_type="none",
+    animation_value_type="IntermediateSVGPaint",
     boxed=True,
     spec="https://www.w3.org/TR/SVG2/painting.html#SpecifyingStrokePaint")}