/src/serenity/Userland/Libraries/LibWeb/HTML/Canvas/CanvasFillStrokeStyles.h

Source
/*
 * Copyright (c) 2020-2022, Andreas Kling <kling@serenityos.org>
 * Copyright (c) 2021-2022, Linus Groh <linusg@serenityos.org>
 * Copyright (c) 2022, Sam Atkins <atkinssj@serenityos.org>
 * Copyright (c) 2023, MacDue <macdue@dueutil.tech>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#pragma once

#include <AK/String.h>
#include <LibWeb/CSS/Parser/Parser.h>
#include <LibWeb/HTML/Canvas/CanvasState.h>
#include <LibWeb/HTML/CanvasGradient.h>
#include <LibWeb/HTML/CanvasPattern.h>

namespace Web::HTML {

// https://html.spec.whatwg.org/multipage/canvas.html#canvasfillstrokestyles
template<typename IncludingClass>
class CanvasFillStrokeStyles {
public:
    ~CanvasFillStrokeStyles() = default;
    using FillOrStrokeStyleVariant = Variant<String, JS::Handle<CanvasGradient>, JS::Handle<CanvasPattern>>;

    void set_fill_style(FillOrStrokeStyleVariant style)
    {
        auto& realm = static_cast<IncludingClass&>(*this).realm();

        // https://html.spec.whatwg.org/multipage/canvas.html#dom-context-2d-fillstyle
        style.visit(
            // 1. If the given value is a string, then:
            [&](String const& string) {
                // 1. Let context be this's canvas attribute's value, if that is an element; otherwise null.
                auto parser = CSS::Parser::Parser::create(CSS::Parser::ParsingContext(realm), string);

                // 2. Let parsedValue be the result of parsing the given value with context if non-null.
                // FIXME: Parse a color value
                // https://drafts.csswg.org/css-color/#parse-a-css-color-value
                auto style_value = parser.parse_as_css_value(CSS::PropertyID::Color);
                if (style_value && style_value->has_color()) {
                    auto parsedValue = style_value->to_color(OptionalNone());

                    // 4. Set this's fill style to parsedValue.
                    my_drawing_state().fill_style = parsedValue;
                } else {
                    // 3. If parsedValue is failure, then return.
                    return;
                }

                // 5. Return.
                return;
            },
            [&](auto fill_or_stroke_style) {
                // FIXME: 2. If the given value is a CanvasPattern object that is marked as not origin-clean, then set this's origin-clean flag to false.

                // 3. Set this's fill style to the given value.
                my_drawing_state().fill_style = fill_or_stroke_style;
            });
    }

    FillOrStrokeStyleVariant fill_style() const
    {
        return my_drawing_state().fill_style.to_js_fill_or_stroke_style();
    }

    void set_stroke_style(FillOrStrokeStyleVariant style)
    {
        auto& realm = static_cast<IncludingClass&>(*this).realm();

        // https://html.spec.whatwg.org/multipage/canvas.html#dom-context-2d-strokestyle

        style.visit(
            // 1. If the given value is a string, then:
            [&](String const& string) {
                // 1. Let context be this's canvas attribute's value, if that is an element; otherwise null.
                auto parser = CSS::Parser::Parser::create(CSS::Parser::ParsingContext(realm), string);

                // 2. Let parsedValue be the result of parsing the given value with context if non-null.
                // FIXME: Parse a color value
                // https://drafts.csswg.org/css-color/#parse-a-css-color-value
                auto style_value = parser.parse_as_css_value(CSS::PropertyID::Color);
                if (style_value && style_value->has_color()) {
                    auto parsedValue = style_value->to_color(OptionalNone());

                    // 4. Set this's stroke style to parsedValue.
                    my_drawing_state().stroke_style = parsedValue;
                } else {
                    // 3. If parsedValue is failure, then return.
                    return;
                }

                // 5. Return.
                return;
            },
            [&](auto fill_or_stroke_style) {
                // FIXME: 2. If the given value is a CanvasPattern object that is marked as not origin-clean, then set this's origin-clean flag to false.

                // 3. Set this's stroke style to the given value.
                my_drawing_state().fill_style = fill_or_stroke_style;
            });
    }

    FillOrStrokeStyleVariant stroke_style() const
    {
        return my_drawing_state().stroke_style.to_js_fill_or_stroke_style();
    }

    WebIDL::ExceptionOr<JS::NonnullGCPtr<CanvasGradient>> create_radial_gradient(double x0, double y0, double r0, double x1, double y1, double r1)
    {
        auto& realm = static_cast<IncludingClass&>(*this).realm();
        return CanvasGradient::create_radial(realm, x0, y0, r0, x1, y1, r1);
    }

    JS::NonnullGCPtr<CanvasGradient> create_linear_gradient(double x0, double y0, double x1, double y1)
    {
        auto& realm = static_cast<IncludingClass&>(*this).realm();
        return CanvasGradient::create_linear(realm, x0, y0, x1, y1).release_value_but_fixme_should_propagate_errors();
    }

    JS::NonnullGCPtr<CanvasGradient> create_conic_gradient(double start_angle, double x, double y)
    {
        auto& realm = static_cast<IncludingClass&>(*this).realm();
        return CanvasGradient::create_conic(realm, start_angle, x, y).release_value_but_fixme_should_propagate_errors();
    }

    WebIDL::ExceptionOr<JS::GCPtr<CanvasPattern>> create_pattern(CanvasImageSource const& image, StringView repetition)
    {
        auto& realm = static_cast<IncludingClass&>(*this).realm();
        return CanvasPattern::create(realm, image, repetition);
    }

protected:
    CanvasFillStrokeStyles() = default;

private:
    CanvasState::DrawingState& my_drawing_state() { return reinterpret_cast<IncludingClass&>(*this).drawing_state(); }
    CanvasState::DrawingState const& my_drawing_state() const { return reinterpret_cast<IncludingClass const&>(*this).drawing_state(); }
};

}

Line	Count	Source
1		/*
2		* Copyright (c) 2020-2022, Andreas Kling <kling@serenityos.org>
3		* Copyright (c) 2021-2022, Linus Groh <linusg@serenityos.org>
4		* Copyright (c) 2022, Sam Atkins <atkinssj@serenityos.org>
5		* Copyright (c) 2023, MacDue <macdue@dueutil.tech>
6		*
7		* SPDX-License-Identifier: BSD-2-Clause
8		*/
9
10		#pragma once
11
12		#include <AK/String.h>
13		#include <LibWeb/CSS/Parser/Parser.h>
14		#include <LibWeb/HTML/Canvas/CanvasState.h>
15		#include <LibWeb/HTML/CanvasGradient.h>
16		#include <LibWeb/HTML/CanvasPattern.h>
17
18		namespace Web::HTML {
19
20		// https://html.spec.whatwg.org/multipage/canvas.html#canvasfillstrokestyles
21		template<typename IncludingClass>
22		class CanvasFillStrokeStyles {
23		public:
24		~CanvasFillStrokeStyles() = default;
25		using FillOrStrokeStyleVariant = Variant<String, JS::Handle<CanvasGradient>, JS::Handle<CanvasPattern>>;
26
27		void set_fill_style(FillOrStrokeStyleVariant style)
28	0	{
29	0	auto& realm = static_cast<IncludingClass&>(*this).realm();
30
31		// https://html.spec.whatwg.org/multipage/canvas.html#dom-context-2d-fillstyle
32	0	style.visit(
33		// 1. If the given value is a string, then:
34	0	[&](String const& string) {
35		// 1. Let context be this's canvas attribute's value, if that is an element; otherwise null.
36	0	auto parser = CSS::Parser::Parser::create(CSS::Parser::ParsingContext(realm), string);
37
38		// 2. Let parsedValue be the result of parsing the given value with context if non-null.
39		// FIXME: Parse a color value
40		// https://drafts.csswg.org/css-color/#parse-a-css-color-value
41	0	auto style_value = parser.parse_as_css_value(CSS::PropertyID::Color);
42	0	if (style_value && style_value->has_color()) {
43	0	auto parsedValue = style_value->to_color(OptionalNone());
44
45		// 4. Set this's fill style to parsedValue.
46	0	my_drawing_state().fill_style = parsedValue;
47	0	} else {
48		// 3. If parsedValue is failure, then return.
49	0	return;
50	0	}
51
52		// 5. Return.
53	0	return;
54	0	},
55	0	[&](auto fill_or_stroke_style) {
56		// FIXME: 2. If the given value is a CanvasPattern object that is marked as not origin-clean, then set this's origin-clean flag to false.
57
58		// 3. Set this's fill style to the given value.
59	0	my_drawing_state().fill_style = fill_or_stroke_style;
60	0	}); Unexecuted instantiation: auto Web::HTML::CanvasFillStrokeStyles<Web::HTML::CanvasRenderingContext2D>::set_fill_style(AK::Variant<AK::String, JS::Handle<Web::HTML::CanvasGradient>, JS::Handle<Web::HTML::CanvasPattern> >)::{lambda(auto:1)#1}::operator()<JS::Handle<Web::HTML::CanvasGradient> >(JS::Handle<Web::HTML::CanvasGradient>) const Unexecuted instantiation: auto Web::HTML::CanvasFillStrokeStyles<Web::HTML::CanvasRenderingContext2D>::set_fill_style(AK::Variant<AK::String, JS::Handle<Web::HTML::CanvasGradient>, JS::Handle<Web::HTML::CanvasPattern> >)::{lambda(auto:1)#1}::operator()<JS::Handle<Web::HTML::CanvasPattern> >(JS::Handle<Web::HTML::CanvasPattern>) const
61	0	}
62
63		FillOrStrokeStyleVariant fill_style() const
64	0	{
65	0	return my_drawing_state().fill_style.to_js_fill_or_stroke_style();
66	0	}
67
68		void set_stroke_style(FillOrStrokeStyleVariant style)
69	0	{
70	0	auto& realm = static_cast<IncludingClass&>(*this).realm();
71
72		// https://html.spec.whatwg.org/multipage/canvas.html#dom-context-2d-strokestyle
73
74	0	style.visit(
75		// 1. If the given value is a string, then:
76	0	[&](String const& string) {
77		// 1. Let context be this's canvas attribute's value, if that is an element; otherwise null.
78	0	auto parser = CSS::Parser::Parser::create(CSS::Parser::ParsingContext(realm), string);
79
80		// 2. Let parsedValue be the result of parsing the given value with context if non-null.
81		// FIXME: Parse a color value
82		// https://drafts.csswg.org/css-color/#parse-a-css-color-value
83	0	auto style_value = parser.parse_as_css_value(CSS::PropertyID::Color);
84	0	if (style_value && style_value->has_color()) {
85	0	auto parsedValue = style_value->to_color(OptionalNone());
86
87		// 4. Set this's stroke style to parsedValue.
88	0	my_drawing_state().stroke_style = parsedValue;
89	0	} else {
90		// 3. If parsedValue is failure, then return.
91	0	return;
92	0	}
93
94		// 5. Return.
95	0	return;
96	0	},
97	0	[&](auto fill_or_stroke_style) {
98		// FIXME: 2. If the given value is a CanvasPattern object that is marked as not origin-clean, then set this's origin-clean flag to false.
99
100		// 3. Set this's stroke style to the given value.
101	0	my_drawing_state().fill_style = fill_or_stroke_style;
102	0	}); Unexecuted instantiation: auto Web::HTML::CanvasFillStrokeStyles<Web::HTML::CanvasRenderingContext2D>::set_stroke_style(AK::Variant<AK::String, JS::Handle<Web::HTML::CanvasGradient>, JS::Handle<Web::HTML::CanvasPattern> >)::{lambda(auto:1)#1}::operator()<JS::Handle<Web::HTML::CanvasGradient> >(JS::Handle<Web::HTML::CanvasGradient>) const Unexecuted instantiation: auto Web::HTML::CanvasFillStrokeStyles<Web::HTML::CanvasRenderingContext2D>::set_stroke_style(AK::Variant<AK::String, JS::Handle<Web::HTML::CanvasGradient>, JS::Handle<Web::HTML::CanvasPattern> >)::{lambda(auto:1)#1}::operator()<JS::Handle<Web::HTML::CanvasPattern> >(JS::Handle<Web::HTML::CanvasPattern>) const
103	0	}
104
105		FillOrStrokeStyleVariant stroke_style() const
106	0	{
107	0	return my_drawing_state().stroke_style.to_js_fill_or_stroke_style();
108	0	}
109
110		WebIDL::ExceptionOr<JS::NonnullGCPtr<CanvasGradient>> create_radial_gradient(double x0, double y0, double r0, double x1, double y1, double r1)
111	0	{
112	0	auto& realm = static_cast<IncludingClass&>(*this).realm();
113	0	return CanvasGradient::create_radial(realm, x0, y0, r0, x1, y1, r1);
114	0	}
115
116		JS::NonnullGCPtr<CanvasGradient> create_linear_gradient(double x0, double y0, double x1, double y1)
117	0	{
118	0	auto& realm = static_cast<IncludingClass&>(*this).realm();
119	0	return CanvasGradient::create_linear(realm, x0, y0, x1, y1).release_value_but_fixme_should_propagate_errors();
120	0	}
121
122		JS::NonnullGCPtr<CanvasGradient> create_conic_gradient(double start_angle, double x, double y)
123	0	{
124	0	auto& realm = static_cast<IncludingClass&>(*this).realm();
125	0	return CanvasGradient::create_conic(realm, start_angle, x, y).release_value_but_fixme_should_propagate_errors();
126	0	}
127
128		WebIDL::ExceptionOr<JS::GCPtr<CanvasPattern>> create_pattern(CanvasImageSource const& image, StringView repetition)
129	0	{
130	0	auto& realm = static_cast<IncludingClass&>(*this).realm();
131	0	return CanvasPattern::create(realm, image, repetition);
132	0	}
133
134		protected:
135		CanvasFillStrokeStyles() = default;
136
137		private:
138	0	CanvasState::DrawingState& my_drawing_state() { return reinterpret_cast<IncludingClass&>(*this).drawing_state(); }
139	0	CanvasState::DrawingState const& my_drawing_state() const { return reinterpret_cast<IncludingClass const&>(*this).drawing_state(); }
140		};
141
142		}

Coverage Report

Created: 2026-05-16 07:03