Merge pull request #6 from dnfield/ast

Parsing, a few test cases

Author: dnfield

packages/vector_graphics_compiler/analysis_options.yaml

@@ -1,4 +1,33 @@
 include: package:flutter_lints/flutter.yaml
 
-# Additional information about this file can be found at
-# https://dart.dev/guides/language/analysis-options
+analyzer:
+  language:
+    strict-raw-types: true
+  strong-mode:
+    implicit-casts: false
+  errors:
+    missing_required_param: error
+    todo: ignore
+
+linter:
+
+  rules:
+    always_declare_return_types: true
+    always_put_control_body_on_new_line: true
+    always_specify_types: true
+    avoid_dynamic_calls: true
+    avoid_redundant_argument_values: true
+    avoid_print: false  # For now, the compiler is printing.
+    prefer_single_quotes: true
+    # flutter_style_todos: true TODO(dnfield): enable this eventually
+    hash_and_equals: true
+    no_default_cases: true
+    only_throw_errors: true
+    prefer_final_fields: true
+    prefer_final_locals: true
+    public_member_api_docs: true
+    recursive_getters: true
+    sort_constructors_first: true
+    sort_unnamed_constructors_first: true
+    test_types_in_equals: true
+    unnecessary_late: true

packages/vector_graphics_compiler/lib/src/geometry/basic_types.dart

@@ -9,6 +9,7 @@ class Point {
   /// Creates a point object with x,y coordinates.
   const Point(this.x, this.y);
 
+  /// The point at the origin of coordinate space.
   static const Point zero = Point(0, 0);
 
   /// The offset along the x-axis of this point.
@@ -25,10 +26,16 @@ class Point {
     return other is Point && other.x == x && other.y == y;
   }
 
+  /// Returns a point whose coordinates are the coordinates of the
+  /// left-hand-side operand (a Point) divided by the scalar right-hand-side
+  /// operand (a double).
   Point operator /(double divisor) {
     return Point(x / divisor, y / divisor);
   }
 
+  /// Returns a point whose coordinates are the coordinates of the
+  /// left-hand-side operand (a Point) multiplied by the scalar right-hand-side
+  /// operand (a double).
   Point operator *(double multiplicand) {
     return Point(x * multiplicand, y * multiplicand);
   }
@@ -80,21 +87,6 @@ class Rect {
   /// The height of the rectangle.
   double get height => bottom - top;
 
-  /// The top left corner of the rect.
-  Point get topLeft => Point(left, top);
-
-  /// The top right corner of the rect.
-  Point get topRight => Point(right, top);
-
-  /// The bottom left corner of the rect.
-  Point get bottomLeft => Point(bottom, left);
-
-  /// The bottom right corner of the rect.
-  Point get bottomRight => Point(bottom, right);
-
-  /// The size of the rectangle, expressed as a [Point].
-  Point get size => Point(width, height);
-
   /// Creates the smallest rectangle that covers the edges of this and `other`.
   Rect expanded(Rect other) {
     return Rect.fromLTRB(
@@ -105,9 +97,6 @@ class Rect {
     );
   }
 
-  @override
-  String toString() => 'Rect.fromLTRB($left, $top, $right, $bottom)';
-
   @override
   int get hashCode => Object.hash(left, top, right, bottom);
 
@@ -119,4 +108,7 @@ class Rect {
         other.right == right &&
         other.bottom == bottom;
   }
+
+  @override
+  String toString() => 'Rect.fromLTRB($left, $top, $right, $bottom)';
 }

packages/vector_graphics_compiler/lib/src/geometry/path.dart

@@ -68,9 +68,14 @@ abstract class PathCommand {
 
   /// Returns a new path command transformed by `matrix`.
   PathCommand transformed(AffineMatrix matrix);
+
+  /// A representation of this path command for dart:ui.
+  String toFlutterString();
 }
 
+/// A straight line from the current point to x,y.
 class LineToCommand extends PathCommand {
+  /// Creates a straight line command from the current point to x,y.
   const LineToCommand(this.x, this.y) : super._(PathCommandType.line);
 
   /// The absolute offset of the destination point for this path from the x
@@ -96,12 +101,15 @@ class LineToCommand extends PathCommand {
   }
 
   @override
-  String toString() {
-    return '..lineTo($x, $y)';
-  }
+  String toFlutterString() => '..lineTo($x, $y)';
+
+  @override
+  String toString() => 'LineToCommand($x, $y)';
 }
 
+/// Moves the current point to x,y as if picking up the pen.
 class MoveToCommand extends PathCommand {
+  /// Creates a new command that moves the current point to x,y without drawing.
   const MoveToCommand(this.x, this.y) : super._(PathCommandType.move);
 
   /// The absolute offset of the destination point for this path from the x
@@ -127,12 +135,17 @@ class MoveToCommand extends PathCommand {
   }
 
   @override
-  String toString() {
-    return '..moveTo($x, $y)';
-  }
+  String toFlutterString() => '..moveTo($x, $y)';
+
+  @override
+  String toString() => 'MoveToCommand($x, $y)';
 }
 
+/// A command describing a cubic Bezier command from the current point to
+/// x3,y3 using control points x1,y1 and x2,y2.
 class CubicToCommand extends PathCommand {
+  /// Creates a new cubic Bezier command from the current point to x3,y3 using
+  /// control points x1,y1 and x2,y2.
   const CubicToCommand(this.x1, this.y1, this.x2, this.y2, this.x3, this.y3)
       : super._(PathCommandType.cubic);
 
@@ -183,12 +196,16 @@ class CubicToCommand extends PathCommand {
   }
 
   @override
-  String toString() {
-    return '..cubicTo($x1, $y1, $x2, $y2, $x3, $y3)';
-  }
+  String toFlutterString() => '..cubicTo($x1, $y1, $x2, $y2, $x3, $y3)';
+
+  @override
+  String toString() => 'CubicToCommand($x1, $y1, $x2, $y2, $x3, $y3)';
 }
 
+/// A straight line from the current point to the current contour start point.
 class CloseCommand extends PathCommand {
+  /// Creates a new straight line from the current point to the current contour
+  /// start point.
   const CloseCommand() : super._(PathCommandType.close);
 
   @override
@@ -205,9 +222,9 @@ class CloseCommand extends PathCommand {
   }
 
   @override
-  String toString() {
-    return '..close()';
-  }
+  String toFlutterString() => '..close()';
+  @override
+  String toString() => 'CloseCommand()';
 }
 
 /// Creates a new builder of [Path] objects.
@@ -311,7 +328,7 @@ class PathBuilder implements PathProxy {
       return;
     }
 
-    final magicRadius = Point(rx, ry) * _kArcApproximationMagic;
+    final Point magicRadius = Point(rx, ry) * _kArcApproximationMagic;
 
     moveTo(rect.left + rx, rect.top);
 
@@ -379,13 +396,9 @@ class PathBuilder implements PathProxy {
   /// path objects with the same commands. By default, the builder will reset
   /// to an initial state.
   Path toPath({bool reset = true}) {
-    // TODO: bounds
-    Rect bounds = Rect.zero;
-
     final Path path = Path(
       commands: _commands,
       fillType: fillType,
-      bounds: bounds,
     );
 
     if (reset) {
@@ -402,7 +415,6 @@ class Path {
   Path({
     List<PathCommand> commands = const <PathCommand>[],
     this.fillType = PathFillType.nonZero,
-    required this.bounds,
   }) {
     _commands.addAll(commands);
   }
@@ -418,9 +430,7 @@ class Path {
   /// The fill type of this path, defaulting to [PathFillType.nonZero].
   final PathFillType fillType;
 
-  /// The bounds of this path object.
-  final Rect bounds;
-
+  /// Creates a new path whose commands and points are transformed by `matrix`.
   Path transformed(AffineMatrix matrix) {
     final List<PathCommand> commands = <PathCommand>[];
     for (final PathCommand command in _commands) {
@@ -429,9 +439,6 @@ class Path {
     return Path(
       commands: commands,
       fillType: fillType,
-      // TODO: is this safe? What the commands have degenerated? Should probably
-      // recalculate this.
-      bounds: matrix.transformRect(bounds),
     );
   }
 
@@ -442,28 +449,40 @@ class Path {
   bool operator ==(Object other) {
     return other is Path &&
         listEquals(_commands, other._commands) &&
-        other.fillType == fillType &&
-        other.bounds == bounds;
+        other.fillType == fillType;
   }
 
-  @override
-  String toString() {
+  /// Returns a string that prints the dart:ui code to create this path.
+  String toFlutterString() {
     final StringBuffer buffer = StringBuffer('Path()');
     if (fillType != PathFillType.nonZero) {
       buffer.write('\n  ..fillType = $fillType');
     }
-    for (final command in commands) {
-      buffer.write('\n  $command');
+    for (final PathCommand command in commands) {
+      buffer.write('\n  ${command.toFlutterString()}');
     }
     buffer.write(';');
     return buffer.toString();
   }
+
+  @override
+  String toString() {
+    final StringBuffer buffer = StringBuffer('Path(');
+    if (commands.isNotEmpty) {
+      buffer.write('\n  commands: <PathCommand>$commands,');
+    }
+    if (fillType != PathFillType.nonZero) {
+      buffer.write('\n  fillType: $fillType,');
+    }
+    buffer.write('\n)');
+    return buffer.toString();
+  }
 }
 
 /// Creates a new [Path] object from an SVG path data string.
 Path parseSvgPathData(String svg) {
   if (svg == '') {
-    return Path(bounds: Rect.zero);
+    return Path();
   }
 
   final SvgPathStringSource parser = SvgPathStringSource(svg);

packages/vector_graphics_compiler/lib/src/geometry/vertices.dart

@@ -4,16 +4,19 @@ import 'basic_types.dart';
 
 /// A description of vertex points for drawing triangles.
 class Vertices {
+  /// Creates a new collection of triangle vertices at the specified points.
   const Vertices(this.vertexPoints);
 
+  /// Creates a new collection of triangle vertices from the specified
+  /// [Float32List], interpreted as x,y pairs.
   factory Vertices.fromFloat32List(Float32List vertices) {
     if (vertices.length.isOdd) {
       throw ArgumentError(
         'must be an even number of vertex points',
         'vertices',
       );
     }
-    final List<Point> vertexPoints = [];
+    final List<Point> vertexPoints = <Point>[];
     for (int index = 0; index < vertices.length; index += 2) {
       vertexPoints.add(Point(vertices[index], vertices[index + 1]));
     }
@@ -28,17 +31,17 @@ class Vertices {
   /// Creates an optimized version of [vertexPoints] where the points are
   /// deduplicated via an index buffer.
   IndexedVertices createIndex() {
-    final pointMap = <Point, int>{};
+    final Map<Point, int> pointMap = <Point, int>{};
     int index = 0;
-    final List<int> indices = [];
-    for (final point in vertexPoints) {
+    final List<int> indices = <int>[];
+    for (final Point point in vertexPoints) {
       indices.add(pointMap.putIfAbsent(point, () => index++));
     }
 
     Float32List pointsToFloat32List(List<Point> points) {
       final Float32List vertices = Float32List(points.length * 2);
       int vertexIndex = 0;
-      for (final point in points) {
+      for (final Point point in points) {
         vertices[vertexIndex++] = point.x;
         vertices[vertexIndex++] = point.y;
       }
@@ -61,6 +64,9 @@ class Vertices {
 /// An optimized version of [Vertices] that uses an index buffer to specify
 /// reused vertex points.
 class IndexedVertices {
+  /// Creates a indexed set of vertices.
+  ///
+  /// Consider using [Vertices.createIndex].
   const IndexedVertices(this.vertices, this.indices);
 
   /// The raw vertex points.

packages/vector_graphics_compiler/lib/src/optimizers.dart

@@ -0,0 +1,57 @@
+import 'paint.dart';
+import 'vector_instructions.dart';
+
+/// An optimization pass for a [VectorInstructions] object.
+///
+/// For example, an optimizer may de-duplicate objects or transform objects
+/// into more efficiently drawable objects.
+///
+/// Optimizers are composable, but may expect certain ordering to reach maximum
+/// efficiency.
+abstract class Optimizer {
+  /// Allows inheriting classes to create const instances.
+  const Optimizer();
+
+  /// Takes `original` and produces a new object that is optimized.
+  VectorInstructions optimize(VectorInstructions original);
+}
+
+/// An optimizer that removes duplicate [Paint] objects and rewrites
+/// [DrawCommand]s to refer to the updated paint index.
+///
+/// The resulting [VectorInstructions.paints] is effectively the original paint
+/// list converted to a set and then back to a list.
+class PaintDeduplicator extends Optimizer {
+  /// Creates a new paint deduplicator.
+  const PaintDeduplicator();
+
+  @override
+  VectorInstructions optimize(VectorInstructions original) {
+    final VectorInstructions result = VectorInstructions(
+      width: original.width,
+      height: original.height,
+      paths: original.paths,
+      paints: <Paint>[],
+      commands: <DrawCommand>[],
+    );
+
+    final Map<Paint, int> paints = <Paint, int>{};
+    for (final DrawCommand command in original.commands) {
+      final Paint originalPaint = original.paints[command.paintId];
+      final int paintId = paints.putIfAbsent(
+        original.paints[command.paintId],
+        () {
+          result.paints.add(originalPaint);
+          return result.paints.length - 1;
+        },
+      );
+      result.commands.add(DrawCommand(
+        command.objectId,
+        paintId,
+        command.type,
+        command.debugString,
+      ));
+    }
+    return result;
+  }
+}