ladybird/Userland/Libraries/LibWeb/HTML/Path2D.cpp
Andreas Kling 8a48246ed1 Everywhere: Stop using NonnullRefPtrVector
This class had slightly confusing semantics and the added weirdness
doesn't seem worth it just so we can say "." instead of "->" when
iterating over a vector of NNRPs.

This patch replaces NonnullRefPtrVector<T> with Vector<NNRP<T>>.
2023-03-06 23:46:35 +01:00

101 lines
4.0 KiB
C++

/*
* Copyright (c) 2022, Sam Atkins <atkinssj@serenityos.org>
* Copyright (c) 2022, Andreas Kling <kling@serenityos.org>
* Copyright (c) 2023, Luke Wilde <lukew@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibWeb/Bindings/Intrinsics.h>
#include <LibWeb/Geometry/DOMMatrix.h>
#include <LibWeb/HTML/Path2D.h>
#include <LibWeb/SVG/AttributeParser.h>
#include <LibWeb/SVG/SVGPathElement.h>
namespace Web::HTML {
WebIDL::ExceptionOr<JS::NonnullGCPtr<Path2D>> Path2D::construct_impl(JS::Realm& realm, Optional<Variant<JS::Handle<Path2D>, DeprecatedString>> const& path)
{
return MUST_OR_THROW_OOM(realm.heap().allocate<Path2D>(realm, realm, path));
}
// https://html.spec.whatwg.org/multipage/canvas.html#dom-path2d
Path2D::Path2D(JS::Realm& realm, Optional<Variant<JS::Handle<Path2D>, DeprecatedString>> const& path)
: PlatformObject(realm)
, CanvasPath(static_cast<Bindings::PlatformObject&>(*this))
{
// 1. Let output be a new Path2D object.
// 2. If path is not given, then return output.
if (!path.has_value())
return;
// 3. If path is a Path2D object, then add all subpaths of path to output and return output.
// (In other words, it returns a copy of the argument.)
if (path->has<JS::Handle<Path2D>>()) {
this->path() = path->get<JS::Handle<Path2D>>()->path();
return;
}
// 4. Let svgPath be the result of parsing and interpreting path according to SVG 2's rules for path data. [SVG]
auto path_instructions = SVG::AttributeParser::parse_path_data(path->get<DeprecatedString>());
auto svg_path = SVG::path_from_path_instructions(path_instructions);
if (!svg_path.segments().is_empty()) {
// 5. Let (x, y) be the last point in svgPath.
auto xy = svg_path.segments().last()->point();
// 6. Add all the subpaths, if any, from svgPath to output.
this->path() = move(svg_path);
// 7. Create a new subpath in output with (x, y) as the only point in the subpath.
this->move_to(xy.x(), xy.y());
}
// 8. Return output.
}
Path2D::~Path2D() = default;
JS::ThrowCompletionOr<void> Path2D::initialize(JS::Realm& realm)
{
MUST_OR_THROW_OOM(Base::initialize(realm));
set_prototype(&Bindings::ensure_web_prototype<Bindings::Path2DPrototype>(realm, "Path2D"));
return {};
}
// https://html.spec.whatwg.org/multipage/canvas.html#dom-path2d-addpath
WebIDL::ExceptionOr<void> Path2D::add_path(JS::NonnullGCPtr<Path2D> path, Geometry::DOMMatrix2DInit& transform)
{
// The addPath(path, transform) method, when invoked on a Path2D object a, must run these steps:
// 1. If the Path2D object path has no subpaths, then return.
if (path->path().segments().is_empty())
return {};
// 2. Let matrix be the result of creating a DOMMatrix from the 2D dictionary transform.
auto matrix = TRY(Geometry::DOMMatrix::create_from_dom_matrix_2d_init(realm(), transform));
// 3. If one or more of matrix's m11 element, m12 element, m21 element, m22 element, m41 element, or m42 element are infinite or NaN, then return.
if (!isfinite(matrix->m11()) || !isfinite(matrix->m12()) || !isfinite(matrix->m21()) || !isfinite(matrix->m22()) || !isfinite(matrix->m41()) || !isfinite(matrix->m42()))
return {};
// 4. Create a copy of all the subpaths in path. Let this copy be known as c.
// 5. Transform all the coordinates and lines in c by the transform matrix matrix.
auto copy = path->path().copy_transformed(Gfx::AffineTransform { static_cast<float>(matrix->m11()), static_cast<float>(matrix->m12()), static_cast<float>(matrix->m21()), static_cast<float>(matrix->m22()), static_cast<float>(matrix->m41()), static_cast<float>(matrix->m42()) });
// 6. Let (x, y) be the last point in the last subpath of c.
auto xy = copy.segments().last()->point();
// 7. Add all the subpaths in c to a.
// FIXME: Is this correct?
this->path().add_path(copy);
// 8. Create a new subpath in a with (x, y) as the only point in the subpath.
this->move_to(xy.x(), xy.y());
return {};
}
}