CanvasRenderingContext2D.h   [plain text]

/*
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#pragma once

#include "CanvasRenderingContext2DBase.h"
#include "CanvasTextAlign.h"
#include "CanvasTextBaseline.h"
#include "FontCascade.h"
#include "FontSelectorClient.h"
#include "HTMLCanvasElement.h"
#include <memory>

namespace WebCore {

class TextMetrics;

class CanvasRenderingContext2D final : public CanvasRenderingContext2DBase {
public:
    static std::unique_ptr<CanvasRenderingContext2D> create(CanvasBase&, bool usesCSSCompatibilityParseMode, bool usesDashboardCompatibilityMode);

    virtual ~CanvasRenderingContext2D();

    HTMLCanvasElement& canvas() const { return downcast<HTMLCanvasElement>(canvasBase()); }

    void drawFocusIfNeeded(Element&);
    void drawFocusIfNeeded(Path2D&, Element&);

    float webkitBackingStorePixelRatio() const { return 1; }

    String font() const;
    void setFont(const String&);

    CanvasTextAlign textAlign() const;
    void setTextAlign(CanvasTextAlign);

    CanvasTextBaseline textBaseline() const;
    void setTextBaseline(CanvasTextBaseline);

    CanvasDirection direction() const;
    void setDirection(CanvasDirection);

    void fillText(const String& text, float x, float y, std::optional<float> maxWidth = std::nullopt);
    void strokeText(const String& text, float x, float y, std::optional<float> maxWidth = std::nullopt);
    Ref<TextMetrics> measureText(const String& text);

    bool is2d() const override { return true; }

private:
    CanvasRenderingContext2D(CanvasBase&, bool usesCSSCompatibilityParseMode, bool usesDashboardCompatibilityMode);

    // The relationship between FontCascade and CanvasRenderingContext2D::FontProxy must hold certain invariants.
    // Therefore, all font operations must pass through the State.
    const FontProxy& fontProxy();

    void drawTextInternal(const String& text, float x, float y, bool fill, std::optional<float> maxWidth = std::nullopt);

    void drawFocusIfNeededInternal(const Path&, Element&);

    void prepareGradientForDashboard(CanvasGradient& gradient) const;

    TextDirection toTextDirection(CanvasRenderingContext2DBase::Direction, const RenderStyle** computedStyle = nullptr) const;

    FloatPoint textOffset(float width, TextDirection);
};

} // namespace WebCore

SPECIALIZE_TYPE_TRAITS_CANVASRENDERINGCONTEXT(WebCore::CanvasRenderingContext2D, is2d())