From dcee161f6aed8491b4f8cd8cb2703cb2375afb78 Mon Sep 17 00:00:00 2001
From: Patrick Walton <pcwalton@mimiga.net>
Date: Mon, 14 Jan 2019 11:13:43 -0800
Subject: [PATCH] Move the path transform iterator to the geometry crate

---
 geometry/src/transform.rs  | 55 +++++++++++++++++++++++++++++++++++
 utils/tile-svg/src/main.rs | 59 ++------------------------------------
 2 files changed, 58 insertions(+), 56 deletions(-)

diff --git a/geometry/src/transform.rs b/geometry/src/transform.rs
index 7f802f04..1f7cff0e 100644
--- a/geometry/src/transform.rs
+++ b/geometry/src/transform.rs
@@ -11,6 +11,7 @@
 //! Applies a transform to paths.
 
 use crate::point::Point2DF32;
+use crate::segment::Segment;
 use crate::simd::F32x4;
 use euclid::Transform2D;
 use lyon_path::PathEvent;
@@ -69,6 +70,60 @@ impl Transform2DF32 {
     }
 }
 
+/// Transforms a path with a SIMD 2D transform.
+pub struct Transform2DF32PathIter<I>
+where
+    I: Iterator<Item = Segment>,
+{
+    iter: I,
+    transform: Transform2DF32,
+}
+
+impl<I> Iterator for Transform2DF32PathIter<I>
+where
+    I: Iterator<Item = Segment>,
+{
+    type Item = Segment;
+
+    #[inline]
+    fn next(&mut self) -> Option<Segment> {
+        // TODO(pcwalton): Can we go faster by transforming an entire line segment with SIMD?
+        let mut segment = self.iter.next()?;
+        if !segment.is_none() {
+            segment
+                .baseline
+                .set_from(&self.transform.transform_point(&segment.baseline.from()));
+            segment
+                .baseline
+                .set_to(&self.transform.transform_point(&segment.baseline.to()));
+            if !segment.is_line() {
+                segment
+                    .ctrl
+                    .set_from(&self.transform.transform_point(&segment.ctrl.from()));
+                if !segment.is_quadratic() {
+                    segment
+                        .ctrl
+                        .set_to(&self.transform.transform_point(&segment.ctrl.to()));
+                }
+            }
+        }
+        Some(segment)
+    }
+}
+
+impl<I> Transform2DF32PathIter<I>
+where
+    I: Iterator<Item = Segment>,
+{
+    #[inline]
+    pub fn new(iter: I, transform: &Transform2DF32) -> Transform2DF32PathIter<I> {
+        Transform2DF32PathIter {
+            iter,
+            transform: *transform,
+        }
+    }
+}
+
 /// Transforms a path with a Euclid 2D transform.
 pub struct Transform2DPathIter<I> where I: Iterator<Item = PathEvent> {
     inner: I,
diff --git a/utils/tile-svg/src/main.rs b/utils/tile-svg/src/main.rs
index fd6ee3b7..8d70a4da 100644
--- a/utils/tile-svg/src/main.rs
+++ b/utils/tile-svg/src/main.rs
@@ -30,7 +30,7 @@ use pathfinder_geometry::segment::{PathEventsToSegments, Segment, SegmentFlags};
 use pathfinder_geometry::segment::{SegmentKind, SegmentsToPathEvents};
 use pathfinder_geometry::simd::{F32x4, I32x4};
 use pathfinder_geometry::stroke::{StrokeStyle, StrokeToFillIter};
-use pathfinder_geometry::transform::Transform2DF32;
+use pathfinder_geometry::transform::{Transform2DF32, Transform2DF32PathIter};
 use pathfinder_geometry::util;
 use rayon::iter::{IndexedParallelIterator, IntoParallelRefIterator, ParallelIterator};
 use rayon::ThreadPoolBuilder;
@@ -257,7 +257,7 @@ impl Scene {
                         let style = scene.push_paint(&Paint::from_svg_paint(&fill.paint));
 
                         let path = UsvgPathToSegments::new(path.segments.iter().cloned());
-                        let path = PathTransformingIter::new(path, &transform);
+                        let path = Transform2DF32PathIter::new(path, &transform);
                         let path = MonotonicConversionIter::new(path);
                         let outline = Outline::from_segments(path);
 
@@ -280,7 +280,7 @@ impl Scene {
                         let path = PathIter::new(path);
                         let path = StrokeToFillIter::new(path, StrokeStyle::new(stroke_width));
                         let path = PathEventsToSegments::new(path);
-                        let path = PathTransformingIter::new(path, &transform);
+                        let path = Transform2DF32PathIter::new(path, &transform);
                         let path = MonotonicConversionIter::new(path);
                         let outline = Outline::from_segments(path);
 
@@ -1362,59 +1362,6 @@ where
     }
 }
 
-// Path transformation utilities
-
-struct PathTransformingIter<I>
-where
-    I: Iterator<Item = Segment>,
-{
-    iter: I,
-    transform: Transform2DF32,
-}
-
-impl<I> Iterator for PathTransformingIter<I>
-where
-    I: Iterator<Item = Segment>,
-{
-    type Item = Segment;
-
-    fn next(&mut self) -> Option<Segment> {
-        // TODO(pcwalton): Can we go faster by transforming an entire line segment with SIMD?
-        let mut segment = self.iter.next()?;
-        if !segment.is_none() {
-            segment
-                .baseline
-                .set_from(&self.transform.transform_point(&segment.baseline.from()));
-            segment
-                .baseline
-                .set_to(&self.transform.transform_point(&segment.baseline.to()));
-            if !segment.is_line() {
-                segment
-                    .ctrl
-                    .set_from(&self.transform.transform_point(&segment.ctrl.from()));
-                if !segment.is_quadratic() {
-                    segment
-                        .ctrl
-                        .set_to(&self.transform.transform_point(&segment.ctrl.to()));
-                }
-            }
-        }
-        Some(segment)
-    }
-}
-
-impl<I> PathTransformingIter<I>
-where
-    I: Iterator<Item = Segment>,
-{
-    fn new(iter: I, transform: &Transform2DF32) -> PathTransformingIter<I> {
-        PathTransformingIter {
-            iter,
-            transform: *transform,
-        }
-    }
-}
-
 // Monotonic conversion utilities
 
 // TODO(pcwalton): I think we only need to be monotonic in Y, maybe?