ColorLayersLoader Class Reference

Helper class to load CPAL/COLR v0 color layers, functionally based off the sample code in the freetype docs. More...

Public Member Functions
	ColorLayersLoader (FT_Face face, FT_UInt baseGlyph)
	Construct a ColorLayersLoader object. The first color layer is selected if there are any.
std::tuple< QPainterPath, QBrush, bool >	layer (const CharacterResult &charResult, const FT_Int32 faceLoadFlags, int *x_advance, int *y_advance)
	Load the current glyph layer.
bool	moveNext ()
	Move to the next glyph layer.
	operator bool () const
	Check whether there are color layers to be loaded.

Private Attributes
FT_UInt	m_baseGlyph
FT_Face	m_face
bool	m_haveLayers
FT_LayerIterator	m_iterator {}
FT_UInt	m_layerColorIndex {}
FT_UInt	m_layerGlyphIndex {}
FT_Color *	m_palette {}

Detailed Description

Helper class to load CPAL/COLR v0 color layers, functionally based off the sample code in the freetype docs.

Definition at line 179 of file KoSvgTextShape_p_glyphs.cpp.

Constructor & Destructor Documentation

ColorLayersLoader()

ColorLayersLoader::ColorLayersLoader ( FT_Face face, FT_UInt baseGlyph )

inline

Construct a ColorLayersLoader object. The first color layer is selected if there are any.

Parameters

face
baseGlyph

Definition at line 189 of file KoSvgTextShape_p_glyphs.cpp.

        : m_face(face)
        , m_baseGlyph(baseGlyph)
    {
        const unsigned short paletteIndex = 0;
        if (FT_Palette_Select(m_face, paletteIndex, &m_palette) != 0) {
            m_palette = nullptr;
        }
        m_haveLayers = moveNext();
    }

References m_face, m_haveLayers, m_palette, and moveNext().

Member Function Documentation

layer()

std::tuple< QPainterPath, QBrush, bool > ColorLayersLoader::layer ( const CharacterResult & charResult, const FT_Int32 faceLoadFlags, int * x_advance, int * y_advance )

inline

Load the current glyph layer.

Parameters

charResult
faceLoadFlags
x_advance	Pointer to the X advance to be adjusted if needed.
y_advance	Pointer to the Y advance to be adjusted if needed.

Returns

std::tuple<QPainterPath, QBrush, bool> {glyphOutline, layerColor, isForeGroundColor}

Definition at line 218 of file KoSvgTextShape_p_glyphs.cpp.

    {
        QBrush layerColor;
        bool isForeGroundColor = false;
 
        if (m_layerColorIndex == 0xFFFF) {
            layerColor = Qt::black;
            isForeGroundColor = true;
        } else {
            const FT_Color color = m_palette[m_layerColorIndex];
            layerColor = QColor(color.red, color.green, color.blue, color.alpha);
        }
        if (const FT_Error err = FT_Load_Glyph(m_face, m_layerGlyphIndex, faceLoadFlags)) {
            warnFlake << "Failed to load glyph, freetype error" << err;
            return {};
        }
        if (m_face->glyph->format == FT_GLYPH_FORMAT_OUTLINE) {
            // Check whether we need to synthesize bold by emboldening the glyph:
            emboldenGlyphIfNeeded(m_face, charResult, x_advance, y_advance);
 
            const QPainterPath p = convertFromFreeTypeOutline(m_face->glyph);
            return {p, layerColor, isForeGroundColor};
        } else {
            warnFlake << "Unsupported glyph format" << glyphFormatToStr(m_face->glyph->format) << "in glyph layers";
            return {};
        }
    }

References convertFromFreeTypeOutline(), emboldenGlyphIfNeeded(), glyphFormatToStr(), m_face, m_layerColorIndex, m_layerGlyphIndex, m_palette, p, and warnFlake.

moveNext()

bool ColorLayersLoader::moveNext ( )

inline

Move to the next glyph layer.

Returns

true if there are more layers.

false if there are no more layers.

Definition at line 252 of file KoSvgTextShape_p_glyphs.cpp.

    {
        m_haveLayers =
            FT_Get_Color_Glyph_Layer(m_face, m_baseGlyph, &m_layerGlyphIndex, &m_layerColorIndex, &m_iterator);
        return m_haveLayers;
    }

References m_baseGlyph, m_face, m_haveLayers, m_iterator, m_layerColorIndex, and m_layerGlyphIndex.

operator bool()

ColorLayersLoader::operator bool ( ) const

inline

Check whether there are color layers to be loaded.

Definition at line 203 of file KoSvgTextShape_p_glyphs.cpp.

    {
        return m_haveLayers && m_palette;
    }

References m_haveLayers, and m_palette.

Member Data Documentation

m_baseGlyph

FT_UInt ColorLayersLoader::m_baseGlyph

private

Definition at line 265 of file KoSvgTextShape_p_glyphs.cpp.

m_face

FT_Face ColorLayersLoader::m_face

private

Definition at line 264 of file KoSvgTextShape_p_glyphs.cpp.

m_haveLayers

bool ColorLayersLoader::m_haveLayers

private

Definition at line 266 of file KoSvgTextShape_p_glyphs.cpp.

m_iterator

FT_LayerIterator ColorLayersLoader::m_iterator {}

private

Definition at line 262 of file KoSvgTextShape_p_glyphs.cpp.

{};

m_layerColorIndex

FT_UInt ColorLayersLoader::m_layerColorIndex {}

private

Definition at line 261 of file KoSvgTextShape_p_glyphs.cpp.

{};

m_layerGlyphIndex

FT_UInt ColorLayersLoader::m_layerGlyphIndex {}

private

Definition at line 260 of file KoSvgTextShape_p_glyphs.cpp.

{};

m_palette

FT_Color* ColorLayersLoader::m_palette {}

private

Definition at line 263 of file KoSvgTextShape_p_glyphs.cpp.

{};

---

The documentation for this class was generated from the following file:

• libs/flake/text/KoSvgTextShape_p_glyphs.cpp