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Diffstat (limited to 'src/3rdparty/freetype/include/freetype/ftcolor.h')
| -rw-r--r-- | src/3rdparty/freetype/include/freetype/ftcolor.h | 1356 |
1 files changed, 1355 insertions, 1 deletions
diff --git a/src/3rdparty/freetype/include/freetype/ftcolor.h b/src/3rdparty/freetype/include/freetype/ftcolor.h index ecc6485e5a..eae200fdf1 100644 --- a/src/3rdparty/freetype/include/freetype/ftcolor.h +++ b/src/3rdparty/freetype/include/freetype/ftcolor.h @@ -4,7 +4,7 @@ * * FreeType's glyph color management (specification). * - * Copyright (C) 2018-2020 by + * Copyright (C) 2018-2023 by * David Turner, Robert Wilhelm, and Werner Lemberg. * * This file is part of the FreeType project, and may only be used, @@ -302,6 +302,1360 @@ FT_BEGIN_HEADER FT_Palette_Set_Foreground_Color( FT_Face face, FT_Color foreground_color ); + + /************************************************************************** + * + * @section: + * layer_management + * + * @title: + * Glyph Layer Management + * + * @abstract: + * Retrieving and manipulating OpenType's 'COLR' table data. + * + * @description: + * The functions described here allow access of colored glyph layer data + * in OpenType's 'COLR' tables. + */ + + + /************************************************************************** + * + * @struct: + * FT_LayerIterator + * + * @description: + * This iterator object is needed for @FT_Get_Color_Glyph_Layer. + * + * @fields: + * num_layers :: + * The number of glyph layers for the requested glyph index. Will be + * set by @FT_Get_Color_Glyph_Layer. + * + * layer :: + * The current layer. Will be set by @FT_Get_Color_Glyph_Layer. + * + * p :: + * An opaque pointer into 'COLR' table data. The caller must set this + * to `NULL` before the first call of @FT_Get_Color_Glyph_Layer. + */ + typedef struct FT_LayerIterator_ + { + FT_UInt num_layers; + FT_UInt layer; + FT_Byte* p; + + } FT_LayerIterator; + + + /************************************************************************** + * + * @function: + * FT_Get_Color_Glyph_Layer + * + * @description: + * This is an interface to the 'COLR' table in OpenType fonts to + * iteratively retrieve the colored glyph layers associated with the + * current glyph slot. + * + * https://docs.microsoft.com/en-us/typography/opentype/spec/colr + * + * The glyph layer data for a given glyph index, if present, provides an + * alternative, multi-color glyph representation: Instead of rendering + * the outline or bitmap with the given glyph index, glyphs with the + * indices and colors returned by this function are rendered layer by + * layer. + * + * The returned elements are ordered in the z~direction from bottom to + * top; the 'n'th element should be rendered with the associated palette + * color and blended on top of the already rendered layers (elements 0, + * 1, ..., n-1). + * + * @input: + * face :: + * A handle to the parent face object. + * + * base_glyph :: + * The glyph index the colored glyph layers are associated with. + * + * @inout: + * iterator :: + * An @FT_LayerIterator object. For the first call you should set + * `iterator->p` to `NULL`. For all following calls, simply use the + * same object again. + * + * @output: + * aglyph_index :: + * The glyph index of the current layer. + * + * acolor_index :: + * The color index into the font face's color palette of the current + * layer. The value 0xFFFF is special; it doesn't reference a palette + * entry but indicates that the text foreground color should be used + * instead (to be set up by the application outside of FreeType). + * + * The color palette can be retrieved with @FT_Palette_Select. + * + * @return: + * Value~1 if everything is OK. If there are no more layers (or if there + * are no layers at all), value~0 gets returned. In case of an error, + * value~0 is returned also. + * + * @note: + * This function is necessary if you want to handle glyph layers by + * yourself. In particular, functions that operate with @FT_GlyphRec + * objects (like @FT_Get_Glyph or @FT_Glyph_To_Bitmap) don't have access + * to this information. + * + * Note that @FT_Render_Glyph is able to handle colored glyph layers + * automatically if the @FT_LOAD_COLOR flag is passed to a previous call + * to @FT_Load_Glyph. [This is an experimental feature.] + * + * @example: + * ``` + * FT_Color* palette; + * FT_LayerIterator iterator; + * + * FT_Bool have_layers; + * FT_UInt layer_glyph_index; + * FT_UInt layer_color_index; + * + * + * error = FT_Palette_Select( face, palette_index, &palette ); + * if ( error ) + * palette = NULL; + * + * iterator.p = NULL; + * have_layers = FT_Get_Color_Glyph_Layer( face, + * glyph_index, + * &layer_glyph_index, + * &layer_color_index, + * &iterator ); + * + * if ( palette && have_layers ) + * { + * do + * { + * FT_Color layer_color; + * + * + * if ( layer_color_index == 0xFFFF ) + * layer_color = text_foreground_color; + * else + * layer_color = palette[layer_color_index]; + * + * // Load and render glyph `layer_glyph_index', then + * // blend resulting pixmap (using color `layer_color') + * // with previously created pixmaps. + * + * } while ( FT_Get_Color_Glyph_Layer( face, + * glyph_index, + * &layer_glyph_index, + * &layer_color_index, + * &iterator ) ); + * } + * ``` + * + * @since: + * 2.10 + */ + FT_EXPORT( FT_Bool ) + FT_Get_Color_Glyph_Layer( FT_Face face, + FT_UInt base_glyph, + FT_UInt *aglyph_index, + FT_UInt *acolor_index, + FT_LayerIterator* iterator ); + + + /************************************************************************** + * + * @enum: + * FT_PaintFormat + * + * @description: + * Enumeration describing the different paint format types of the v1 + * extensions to the 'COLR' table, see + * 'https://github.com/googlefonts/colr-gradients-spec'. + * + * The enumeration values loosely correspond with the format numbers of + * the specification: FreeType always returns a fully specified 'Paint' + * structure for the 'Transform', 'Translate', 'Scale', 'Rotate', and + * 'Skew' table types even though the specification has different formats + * depending on whether or not a center is specified, whether the scale + * is uniform in x and y~direction or not, etc. Also, only non-variable + * format identifiers are listed in this enumeration; as soon as support + * for variable 'COLR' v1 fonts is implemented, interpolation is + * performed dependent on axis coordinates, which are configured on the + * @FT_Face through @FT_Set_Var_Design_Coordinates. This implies that + * always static, readily interpolated values are returned in the 'Paint' + * structures. + * + * @since: + * 2.13 + */ + typedef enum FT_PaintFormat_ + { + FT_COLR_PAINTFORMAT_COLR_LAYERS = 1, + FT_COLR_PAINTFORMAT_SOLID = 2, + FT_COLR_PAINTFORMAT_LINEAR_GRADIENT = 4, + FT_COLR_PAINTFORMAT_RADIAL_GRADIENT = 6, + FT_COLR_PAINTFORMAT_SWEEP_GRADIENT = 8, + FT_COLR_PAINTFORMAT_GLYPH = 10, + FT_COLR_PAINTFORMAT_COLR_GLYPH = 11, + FT_COLR_PAINTFORMAT_TRANSFORM = 12, + FT_COLR_PAINTFORMAT_TRANSLATE = 14, + FT_COLR_PAINTFORMAT_SCALE = 16, + FT_COLR_PAINTFORMAT_ROTATE = 24, + FT_COLR_PAINTFORMAT_SKEW = 28, + FT_COLR_PAINTFORMAT_COMPOSITE = 32, + FT_COLR_PAINT_FORMAT_MAX = 33, + FT_COLR_PAINTFORMAT_UNSUPPORTED = 255 + + } FT_PaintFormat; + + + /************************************************************************** + * + * @struct: + * FT_ColorStopIterator + * + * @description: + * This iterator object is needed for @FT_Get_Colorline_Stops. It keeps + * state while iterating over the stops of an @FT_ColorLine, representing + * the `ColorLine` struct of the v1 extensions to 'COLR', see + * 'https://github.com/googlefonts/colr-gradients-spec'. Do not manually + * modify fields of this iterator. + * + * @fields: + * num_color_stops :: + * The number of color stops for the requested glyph index. Set by + * @FT_Get_Paint. + * + * current_color_stop :: + * The current color stop. Set by @FT_Get_Colorline_Stops. + * + * p :: + * An opaque pointer into 'COLR' table data. Set by @FT_Get_Paint. + * Updated by @FT_Get_Colorline_Stops. + * + * read_variable :: + * A boolean keeping track of whether variable color lines are to be + * read. Set by @FT_Get_Paint. + * + * @since: + * 2.13 + */ + typedef struct FT_ColorStopIterator_ + { + FT_UInt num_color_stops; + FT_UInt current_color_stop; + + FT_Byte* p; + + FT_Bool read_variable; + + } FT_ColorStopIterator; + + + /************************************************************************** + * + * @struct: + * FT_ColorIndex + * + * @description: + * A structure representing a `ColorIndex` value of the 'COLR' v1 + * extensions, see 'https://github.com/googlefonts/colr-gradients-spec'. + * + * @fields: + * palette_index :: + * The palette index into a 'CPAL' palette. + * + * alpha :: + * Alpha transparency value multiplied with the value from 'CPAL'. + * + * @since: + * 2.13 + */ + typedef struct FT_ColorIndex_ + { + FT_UInt16 palette_index; + FT_F2Dot14 alpha; + + } FT_ColorIndex; + + + /************************************************************************** + * + * @struct: + * FT_ColorStop + * + * @description: + * A structure representing a `ColorStop` value of the 'COLR' v1 + * extensions, see 'https://github.com/googlefonts/colr-gradients-spec'. + * + * @fields: + * stop_offset :: + * The stop offset along the gradient, expressed as a 16.16 fixed-point + * coordinate. + * + * color :: + * The color information for this stop, see @FT_ColorIndex. + * + * @since: + * 2.13 + */ + typedef struct FT_ColorStop_ + { + FT_Fixed stop_offset; + FT_ColorIndex color; + + } FT_ColorStop; + + + /************************************************************************** + * + * @enum: + * FT_PaintExtend + * + * @description: + * An enumeration representing the 'Extend' mode of the 'COLR' v1 + * extensions, see 'https://github.com/googlefonts/colr-gradients-spec'. + * It describes how the gradient fill continues at the other boundaries. + * + * @since: + * 2.13 + */ + typedef enum FT_PaintExtend_ + { + FT_COLR_PAINT_EXTEND_PAD = 0, + FT_COLR_PAINT_EXTEND_REPEAT = 1, + FT_COLR_PAINT_EXTEND_REFLECT = 2 + + } FT_PaintExtend; + + + /************************************************************************** + * + * @struct: + * FT_ColorLine + * + * @description: + * A structure representing a `ColorLine` value of the 'COLR' v1 + * extensions, see 'https://github.com/googlefonts/colr-gradients-spec'. + * It describes a list of color stops along the defined gradient. + * + * @fields: + * extend :: + * The extend mode at the outer boundaries, see @FT_PaintExtend. + * + * color_stop_iterator :: + * The @FT_ColorStopIterator used to enumerate and retrieve the + * actual @FT_ColorStop's. + * + * @since: + * 2.13 + */ + typedef struct FT_ColorLine_ + { + FT_PaintExtend extend; + FT_ColorStopIterator color_stop_iterator; + + } FT_ColorLine; + + + /************************************************************************** + * + * @struct: + * FT_Affine23 + * + * @description: + * A structure used to store a 2x3 matrix. Coefficients are in + * 16.16 fixed-point format. The computation performed is + * + * ``` + * x' = x*xx + y*xy + dx + * y' = x*yx + y*yy + dy + * ``` + * + * @fields: + * xx :: + * Matrix coefficient. + * + * xy :: + * Matrix coefficient. + * + * dx :: + * x translation. + * + * yx :: + * Matrix coefficient. + * + * yy :: + * Matrix coefficient. + * + * dy :: + * y translation. + * + * @since: + * 2.13 + */ + typedef struct FT_Affine_23_ + { + FT_Fixed xx, xy, dx; + FT_Fixed yx, yy, dy; + + } FT_Affine23; + + + /************************************************************************** + * + * @enum: + * FT_Composite_Mode + * + * @description: + * An enumeration listing the 'COLR' v1 composite modes used in + * @FT_PaintComposite. For more details on each paint mode, see + * 'https://www.w3.org/TR/compositing-1/#porterduffcompositingoperators'. + * + * @since: + * 2.13 + */ + typedef enum FT_Composite_Mode_ + { + FT_COLR_COMPOSITE_CLEAR = 0, + FT_COLR_COMPOSITE_SRC = 1, + FT_COLR_COMPOSITE_DEST = 2, + FT_COLR_COMPOSITE_SRC_OVER = 3, + FT_COLR_COMPOSITE_DEST_OVER = 4, + FT_COLR_COMPOSITE_SRC_IN = 5, + FT_COLR_COMPOSITE_DEST_IN = 6, + FT_COLR_COMPOSITE_SRC_OUT = 7, + FT_COLR_COMPOSITE_DEST_OUT = 8, + FT_COLR_COMPOSITE_SRC_ATOP = 9, + FT_COLR_COMPOSITE_DEST_ATOP = 10, + FT_COLR_COMPOSITE_XOR = 11, + FT_COLR_COMPOSITE_PLUS = 12, + FT_COLR_COMPOSITE_SCREEN = 13, + FT_COLR_COMPOSITE_OVERLAY = 14, + FT_COLR_COMPOSITE_DARKEN = 15, + FT_COLR_COMPOSITE_LIGHTEN = 16, + FT_COLR_COMPOSITE_COLOR_DODGE = 17, + FT_COLR_COMPOSITE_COLOR_BURN = 18, + FT_COLR_COMPOSITE_HARD_LIGHT = 19, + FT_COLR_COMPOSITE_SOFT_LIGHT = 20, + FT_COLR_COMPOSITE_DIFFERENCE = 21, + FT_COLR_COMPOSITE_EXCLUSION = 22, + FT_COLR_COMPOSITE_MULTIPLY = 23, + FT_COLR_COMPOSITE_HSL_HUE = 24, + FT_COLR_COMPOSITE_HSL_SATURATION = 25, + FT_COLR_COMPOSITE_HSL_COLOR = 26, + FT_COLR_COMPOSITE_HSL_LUMINOSITY = 27, + FT_COLR_COMPOSITE_MAX = 28 + + } FT_Composite_Mode; + + + /************************************************************************** + * + * @struct: + * FT_OpaquePaint + * + * @description: + * A structure representing an offset to a `Paint` value stored in any + * of the paint tables of a 'COLR' v1 font. Compare Offset<24> there. + * When 'COLR' v1 paint tables represented by FreeType objects such as + * @FT_PaintColrLayers, @FT_PaintComposite, or @FT_PaintTransform + * reference downstream nested paint tables, we do not immediately + * retrieve them but encapsulate their location in this type. Use + * @FT_Get_Paint to retrieve the actual @FT_COLR_Paint object that + * describes the details of the respective paint table. + * + * @fields: + * p :: + * An internal offset to a Paint table, needs to be set to NULL before + * passing this struct as an argument to @FT_Get_Paint. + * + * insert_root_transform :: + * An internal boolean to track whether an initial root transform is + * to be provided. Do not set this value. + * + * @since: + * 2.13 + */ + typedef struct FT_Opaque_Paint_ + { + FT_Byte* p; + FT_Bool insert_root_transform; + } FT_OpaquePaint; + + + /************************************************************************** + * + * @struct: + * FT_PaintColrLayers + * + * @description: + * A structure representing a `PaintColrLayers` table of a 'COLR' v1 + * font. This table describes a set of layers that are to be composited + * with composite mode `FT_COLR_COMPOSITE_SRC_OVER`. The return value + * of this function is an @FT_LayerIterator initialized so that it can + * be used with @FT_Get_Paint_Layers to retrieve the @FT_OpaquePaint + * objects as references to each layer. + * + * @fields: + * layer_iterator :: + * The layer iterator that describes the layers of this paint. + * + * @since: + * 2.13 + */ + typedef struct FT_PaintColrLayers_ + { + FT_LayerIterator layer_iterator; + + } FT_PaintColrLayers; + + + /************************************************************************** + * + * @struct: + * FT_PaintSolid + * + * @description: + * A structure representing a `PaintSolid` value of the 'COLR' v1 + * extensions, see 'https://github.com/googlefonts/colr-gradients-spec'. + * Using a `PaintSolid` value means that the glyph layer filled with + * this paint is solid-colored and does not contain a gradient. + * + * @fields: + * color :: + * The color information for this solid paint, see @FT_ColorIndex. + * + * @since: + * 2.13 + */ + typedef struct FT_PaintSolid_ + { + FT_ColorIndex color; + + } FT_PaintSolid; + + + /************************************************************************** + * + * @struct: + * FT_PaintLinearGradient + * + * @description: + * A structure representing a `PaintLinearGradient` value of the 'COLR' + * v1 extensions, see + * 'https://github.com/googlefonts/colr-gradients-spec'. The glyph + * layer filled with this paint is drawn filled with a linear gradient. + * + * @fields: + * colorline :: + * The @FT_ColorLine information for this paint, i.e., the list of + * color stops along the gradient. + * + * p0 :: + * The starting point of the gradient definition in font units + * represented as a 16.16 fixed-point `FT_Vector`. + * + * p1 :: + * The end point of the gradient definition in font units + * represented as a 16.16 fixed-point `FT_Vector`. + * + * p2 :: + * Optional point~p2 to rotate the gradient in font units + * represented as a 16.16 fixed-point `FT_Vector`. + * Otherwise equal to~p0. + * + * @since: + * 2.13 + */ + typedef struct FT_PaintLinearGradient_ + { + FT_ColorLine colorline; + + /* TODO: Potentially expose those as x0, y0 etc. */ + FT_Vector p0; + FT_Vector p1; + FT_Vector p2; + + } FT_PaintLinearGradient; + + + /************************************************************************** + * + * @struct: + * FT_PaintRadialGradient + * + * @description: + * A structure representing a `PaintRadialGradient` value of the 'COLR' + * v1 extensions, see + * 'https://github.com/googlefonts/colr-gradients-spec'. The glyph + * layer filled with this paint is drawn filled with a radial gradient. + * + * @fields: + * colorline :: + * The @FT_ColorLine information for this paint, i.e., the list of + * color stops along the gradient. + * + * c0 :: + * The center of the starting point of the radial gradient in font + * units represented as a 16.16 fixed-point `FT_Vector`. + * + * r0 :: + * The radius of the starting circle of the radial gradient in font + * units represented as a 16.16 fixed-point value. + * + * c1 :: + * The center of the end point of the radial gradient in font units + * represented as a 16.16 fixed-point `FT_Vector`. + * + * r1 :: + * The radius of the end circle of the radial gradient in font + * units represented as a 16.16 fixed-point value. + * + * @since: + * 2.13 + */ + typedef struct FT_PaintRadialGradient_ + { + FT_ColorLine colorline; + + FT_Vector c0; + FT_Pos r0; + FT_Vector c1; + FT_Pos r1; + + } FT_PaintRadialGradient; + + + /************************************************************************** + * + * @struct: + * FT_PaintSweepGradient + * + * @description: + * A structure representing a `PaintSweepGradient` value of the 'COLR' + * v1 extensions, see + * 'https://github.com/googlefonts/colr-gradients-spec'. The glyph + * layer filled with this paint is drawn filled with a sweep gradient + * from `start_angle` to `end_angle`. + * + * @fields: + * colorline :: + * The @FT_ColorLine information for this paint, i.e., the list of + * color stops along the gradient. + * + * center :: + * The center of the sweep gradient in font units represented as a + * vector of 16.16 fixed-point values. + * + * start_angle :: + * The start angle of the sweep gradient in 16.16 fixed-point + * format specifying degrees divided by 180.0 (as in the + * spec). Multiply by 180.0f to receive degrees value. Values are + * given counter-clockwise, starting from the (positive) y~axis. + * + * end_angle :: + * The end angle of the sweep gradient in 16.16 fixed-point + * format specifying degrees divided by 180.0 (as in the + * spec). Multiply by 180.0f to receive degrees value. Values are + * given counter-clockwise, starting from the (positive) y~axis. + * + * @since: + * 2.13 + */ + typedef struct FT_PaintSweepGradient_ + { + FT_ColorLine colorline; + + FT_Vector center; + FT_Fixed start_angle; + FT_Fixed end_angle; + + } FT_PaintSweepGradient; + + + /************************************************************************** + * + * @struct: + * FT_PaintGlyph + * + * @description: + * A structure representing a 'COLR' v1 `PaintGlyph` paint table. + * + * @fields: + * paint :: + * An opaque paint object pointing to a `Paint` table that serves as + * the fill for the glyph ID. + * + * glyphID :: + * The glyph ID from the 'glyf' table, which serves as the contour + * information that is filled with paint. + * + * @since: + * 2.13 + */ + typedef struct FT_PaintGlyph_ + { + FT_OpaquePaint paint; + FT_UInt glyphID; + + } FT_PaintGlyph; + + + /************************************************************************** + * + * @struct: + * FT_PaintColrGlyph + * + * @description: + * A structure representing a 'COLR' v1 `PaintColorGlyph` paint table. + * + * @fields: + * glyphID :: + * The glyph ID from the `BaseGlyphV1List` table that is drawn for + * this paint. + * + * @since: + * 2.13 + */ + typedef struct FT_PaintColrGlyph_ + { + FT_UInt glyphID; + + } FT_PaintColrGlyph; + + + /************************************************************************** + * + * @struct: + * FT_PaintTransform + * + * @description: + * A structure representing a 'COLR' v1 `PaintTransform` paint table. + * + * @fields: + * paint :: + * An opaque paint that is subject to being transformed. + * + * affine :: + * A 2x3 transformation matrix in @FT_Affine23 format containing + * 16.16 fixed-point values. + * + * @since: + * 2.13 + */ + typedef struct FT_PaintTransform_ + { + FT_OpaquePaint paint; + FT_Affine23 affine; + + } FT_PaintTransform; + + + /************************************************************************** + * + * @struct: + * FT_PaintTranslate + * + * @description: + * A structure representing a 'COLR' v1 `PaintTranslate` paint table. + * Used for translating downstream paints by a given x and y~delta. + * + * @fields: + * paint :: + * An @FT_OpaquePaint object referencing the paint that is to be + * rotated. + * + * dx :: + * Translation in x~direction in font units represented as a + * 16.16 fixed-point value. + * + * dy :: + * Translation in y~direction in font units represented as a + * 16.16 fixed-point value. + * + * @since: + * 2.13 + */ + typedef struct FT_PaintTranslate_ + { + FT_OpaquePaint paint; + + FT_Fixed dx; + FT_Fixed dy; + + } FT_PaintTranslate; + + + /************************************************************************** + * + * @struct: + * FT_PaintScale + * + * @description: + * A structure representing all of the 'COLR' v1 'PaintScale*' paint + * tables. Used for scaling downstream paints by a given x and y~scale, + * with a given center. This structure is used for all 'PaintScale*' + * types that are part of specification; fields of this structure are + * filled accordingly. If there is a center, the center values are set, + * otherwise they are set to the zero coordinate. If the source font + * file has 'PaintScaleUniform*' set, the scale values are set + * accordingly to the same value. + * + * @fields: + * paint :: + * An @FT_OpaquePaint object referencing the paint that is to be + * scaled. + * + * scale_x :: + * Scale factor in x~direction represented as a + * 16.16 fixed-point value. + * + * scale_y :: + * Scale factor in y~direction represented as a + * 16.16 fixed-point value. + * + * center_x :: + * x~coordinate of center point to scale from represented as a + * 16.16 fixed-point value. + * + * center_y :: + * y~coordinate of center point to scale from represented as a + * 16.16 fixed-point value. + * + * @since: + * 2.13 + */ + typedef struct FT_PaintScale_ + { + FT_OpaquePaint paint; + + FT_Fixed scale_x; + FT_Fixed scale_y; + + FT_Fixed center_x; + FT_Fixed center_y; + + } FT_PaintScale; + + + /************************************************************************** + * + * @struct: + * FT_PaintRotate + * + * @description: + * A structure representing a 'COLR' v1 `PaintRotate` paint table. Used + * for rotating downstream paints with a given center and angle. + * + * @fields: + * paint :: + * An @FT_OpaquePaint object referencing the paint that is to be + * rotated. + * + * angle :: + * The rotation angle that is to be applied in degrees divided by + * 180.0 (as in the spec) represented as a 16.16 fixed-point + * value. Multiply by 180.0f to receive degrees value. + * + * center_x :: + * The x~coordinate of the pivot point of the rotation in font + * units represented as a 16.16 fixed-point value. + * + * center_y :: + * The y~coordinate of the pivot point of the rotation in font + * units represented as a 16.16 fixed-point value. + * + * @since: + * 2.13 + */ + + typedef struct FT_PaintRotate_ + { + FT_OpaquePaint paint; + + FT_Fixed angle; + + FT_Fixed center_x; + FT_Fixed center_y; + + } FT_PaintRotate; + + + /************************************************************************** + * + * @struct: + * FT_PaintSkew + * + * @description: + * A structure representing a 'COLR' v1 `PaintSkew` paint table. Used + * for skewing or shearing downstream paints by a given center and + * angle. + * + * @fields: + * paint :: + * An @FT_OpaquePaint object referencing the paint that is to be + * skewed. + * + * x_skew_angle :: + * The skewing angle in x~direction in degrees divided by 180.0 + * (as in the spec) represented as a 16.16 fixed-point + * value. Multiply by 180.0f to receive degrees. + * + * y_skew_angle :: + * The skewing angle in y~direction in degrees divided by 180.0 + * (as in the spec) represented as a 16.16 fixed-point + * value. Multiply by 180.0f to receive degrees. + * + * center_x :: + * The x~coordinate of the pivot point of the skew in font units + * represented as a 16.16 fixed-point value. + * + * center_y :: + * The y~coordinate of the pivot point of the skew in font units + * represented as a 16.16 fixed-point value. + * + * @since: + * 2.13 + */ + typedef struct FT_PaintSkew_ + { + FT_OpaquePaint paint; + + FT_Fixed x_skew_angle; + FT_Fixed y_skew_angle; + + FT_Fixed center_x; + FT_Fixed center_y; + + } FT_PaintSkew; + + + /************************************************************************** + * + * @struct: + * FT_PaintComposite + * + * @description: + * A structure representing a 'COLR' v1 `PaintComposite` paint table. + * Used for compositing two paints in a 'COLR' v1 directed acyclic graph. + * + * @fields: + * source_paint :: + * An @FT_OpaquePaint object referencing the source that is to be + * composited. + * + * composite_mode :: + * An @FT_Composite_Mode enum value determining the composition + * operation. + * + * backdrop_paint :: + * An @FT_OpaquePaint object referencing the backdrop paint that + * `source_paint` is composited onto. + * + * @since: + * 2.13 + */ + typedef struct FT_PaintComposite_ + { + FT_OpaquePaint source_paint; + FT_Composite_Mode composite_mode; + FT_OpaquePaint backdrop_paint; + + } FT_PaintComposite; + + + /************************************************************************** + * + * @union: + * FT_COLR_Paint + * + * @description: + * A union object representing format and details of a paint table of a + * 'COLR' v1 font, see + * 'https://github.com/googlefonts/colr-gradients-spec'. Use + * @FT_Get_Paint to retrieve a @FT_COLR_Paint for an @FT_OpaquePaint + * object. + * + * @fields: + * format :: + * The gradient format for this Paint structure. + * + * u :: + * Union of all paint table types: + * + * * @FT_PaintColrLayers + * * @FT_PaintGlyph + * * @FT_PaintSolid + * * @FT_PaintLinearGradient + * * @FT_PaintRadialGradient + * * @FT_PaintSweepGradient + * * @FT_PaintTransform + * * @FT_PaintTranslate + * * @FT_PaintRotate + * * @FT_PaintSkew + * * @FT_PaintComposite + * * @FT_PaintColrGlyph + * + * @since: + * 2.13 + */ + typedef struct FT_COLR_Paint_ + { + FT_PaintFormat format; + + union + { + FT_PaintColrLayers colr_layers; + FT_PaintGlyph glyph; + FT_PaintSolid solid; + FT_PaintLinearGradient linear_gradient; + FT_PaintRadialGradient radial_gradient; + FT_PaintSweepGradient sweep_gradient; + FT_PaintTransform transform; + FT_PaintTranslate translate; + FT_PaintScale scale; + FT_PaintRotate rotate; + FT_PaintSkew skew; + FT_PaintComposite composite; + FT_PaintColrGlyph colr_glyph; + + } u; + + } FT_COLR_Paint; + + + /************************************************************************** + * + * @enum: + * FT_Color_Root_Transform + * + * @description: + * An enumeration to specify whether @FT_Get_Color_Glyph_Paint is to + * return a root transform to configure the client's graphics context + * matrix. + * + * @values: + * FT_COLOR_INCLUDE_ROOT_TRANSFORM :: + * Do include the root transform as the initial @FT_COLR_Paint object. + * + * FT_COLOR_NO_ROOT_TRANSFORM :: + * Do not output an initial root transform. + * + * @since: + * 2.13 + */ + typedef enum FT_Color_Root_Transform_ + { + FT_COLOR_INCLUDE_ROOT_TRANSFORM, + FT_COLOR_NO_ROOT_TRANSFORM, + + FT_COLOR_ROOT_TRANSFORM_MAX + + } FT_Color_Root_Transform; + + + /************************************************************************** + * + * @struct: + * FT_ClipBox + * + * @description: + * A structure representing a 'COLR' v1 'ClipBox' table. 'COLR' v1 + * glyphs may optionally define a clip box for aiding allocation or + * defining a maximum drawable region. Use @FT_Get_Color_Glyph_ClipBox + * to retrieve it. + * + * @fields: + * bottom_left :: + * The bottom left corner of the clip box as an @FT_Vector with + * fixed-point coordinates in 26.6 format. + * + * top_left :: + * The top left corner of the clip box as an @FT_Vector with + * fixed-point coordinates in 26.6 format. + * + * top_right :: + * The top right corner of the clip box as an @FT_Vector with + * fixed-point coordinates in 26.6 format. + * + * bottom_right :: + * The bottom right corner of the clip box as an @FT_Vector with + * fixed-point coordinates in 26.6 format. + * + * @since: + * 2.13 + */ + typedef struct FT_ClipBox_ + { + FT_Vector bottom_left; + FT_Vector top_left; + FT_Vector top_right; + FT_Vector bottom_right; + + } FT_ClipBox; + + + /************************************************************************** + * + * @function: + * FT_Get_Color_Glyph_Paint + * + * @description: + * This is the starting point and interface to color gradient + * information in a 'COLR' v1 table in OpenType fonts to recursively + * retrieve the paint tables for the directed acyclic graph of a colored + * glyph, given a glyph ID. + * + * https://github.com/googlefonts/colr-gradients-spec + * + * In a 'COLR' v1 font, each color glyph defines a directed acyclic + * graph of nested paint tables, such as `PaintGlyph`, `PaintSolid`, + * `PaintLinearGradient`, `PaintRadialGradient`, and so on. Using this + * function and specifying a glyph ID, one retrieves the root paint + * table for this glyph ID. + * + * This function allows control whether an initial root transform is + * returned to configure scaling, transform, and translation correctly + * on the client's graphics context. The initial root transform is + * computed and returned according to the values configured for @FT_Size + * and @FT_Set_Transform on the @FT_Face object, see below for details + * of the `root_transform` parameter. This has implications for a + * client 'COLR' v1 implementation: When this function returns an + * initially computed root transform, at the time of executing the + * @FT_PaintGlyph operation, the contours should be retrieved using + * @FT_Load_Glyph at unscaled, untransformed size. This is because the + * root transform applied to the graphics context will take care of + * correct scaling. + * + * Alternatively, to allow hinting of contours, at the time of executing + * @FT_Load_Glyph, the current graphics context transformation matrix + * can be decomposed into a scaling matrix and a remainder, and + * @FT_Load_Glyph can be used to retrieve the contours at scaled size. + * Care must then be taken to blit or clip to the graphics context with + * taking this remainder transformation into account. + * + * @input: + * face :: + * A handle to the parent face object. + * + * base_glyph :: + * The glyph index for which to retrieve the root paint table. + * + * root_transform :: + * Specifies whether an initially computed root is returned by the + * @FT_PaintTransform operation to account for the activated size + * (see @FT_Activate_Size) and the configured transform and translate + * (see @FT_Set_Transform). + * + * This root transform is returned before nodes of the glyph graph of + * the font are returned. Subsequent @FT_COLR_Paint structures + * contain unscaled and untransformed values. The inserted root + * transform enables the client application to apply an initial + * transform to its graphics context. When executing subsequent + * FT_COLR_Paint operations, values from @FT_COLR_Paint operations + * will ultimately be correctly scaled because of the root transform + * applied to the graphics context. Use + * @FT_COLOR_INCLUDE_ROOT_TRANSFORM to include the root transform, use + * @FT_COLOR_NO_ROOT_TRANSFORM to not include it. The latter may be + * useful when traversing the 'COLR' v1 glyph graph and reaching a + * @FT_PaintColrGlyph. When recursing into @FT_PaintColrGlyph and + * painting that inline, no additional root transform is needed as it + * has already been applied to the graphics context at the beginning + * of drawing this glyph. + * + * @output: + * paint :: + * The @FT_OpaquePaint object that references the actual paint table. + * + * The respective actual @FT_COLR_Paint object is retrieved via + * @FT_Get_Paint. + * + * @return: + * Value~1 if everything is OK. If no color glyph is found, or the root + * paint could not be retrieved, value~0 gets returned. In case of an + * error, value~0 is returned also. + * + * @since: + * 2.13 + */ + FT_EXPORT( FT_Bool ) + FT_Get_Color_Glyph_Paint( FT_Face face, + FT_UInt base_glyph, + FT_Color_Root_Transform root_transform, + FT_OpaquePaint* paint ); + + + /************************************************************************** + * + * @function: + * FT_Get_Color_Glyph_ClipBox + * + * @description: + * Search for a 'COLR' v1 clip box for the specified `base_glyph` and + * fill the `clip_box` parameter with the 'COLR' v1 'ClipBox' information + * if one is found. + * + * @input: + * face :: + * A handle to the parent face object. + * + * base_glyph :: + * The glyph index for which to retrieve the clip box. + * + * @output: + * clip_box :: + * The clip box for the requested `base_glyph` if one is found. The + * clip box is computed taking scale and transformations configured on + * the @FT_Face into account. @FT_ClipBox contains @FT_Vector values + * in 26.6 format. + * + * @return: + * Value~1 if a clip box is found. If no clip box is found or an error + * occured, value~0 is returned. + * + * @note: + * To retrieve the clip box in font units, reset scale to units-per-em + * and remove transforms configured using @FT_Set_Transform. + * + * @since: + * 2.13 + */ + FT_EXPORT( FT_Bool ) + FT_Get_Color_Glyph_ClipBox( FT_Face face, + FT_UInt base_glyph, + FT_ClipBox* clip_box ); + + + /************************************************************************** + * + * @function: + * FT_Get_Paint_Layers + * + * @description: + * Access the layers of a `PaintColrLayers` table. + * + * If the root paint of a color glyph, or a nested paint of a 'COLR' + * glyph is a `PaintColrLayers` table, this function retrieves the + * layers of the `PaintColrLayers` table. + * + * The @FT_PaintColrLayers object contains an @FT_LayerIterator, which + * is used here to iterate over the layers. Each layer is returned as + * an @FT_OpaquePaint object, which then can be used with @FT_Get_Paint + * to retrieve the actual paint object. + * + * @input: + * face :: + * A handle to the parent face object. + * + * @inout: + * iterator :: + * The @FT_LayerIterator from an @FT_PaintColrLayers object, for which + * the layers are to be retrieved. The internal state of the iterator + * is incremented after one call to this function for retrieving one + * layer. + * + * @output: + * paint :: + * The @FT_OpaquePaint object that references the actual paint table. + * The respective actual @FT_COLR_Paint object is retrieved via + * @FT_Get_Paint. + * + * @return: + * Value~1 if everything is OK. Value~0 gets returned when the paint + * object can not be retrieved or any other error occurs. + * + * @since: + * 2.13 + */ + FT_EXPORT( FT_Bool ) + FT_Get_Paint_Layers( FT_Face face, + FT_LayerIterator* iterator, + FT_OpaquePaint* paint ); + + + /************************************************************************** + * + * @function: + * FT_Get_Colorline_Stops + * + * @description: + * This is an interface to color gradient information in a 'COLR' v1 + * table in OpenType fonts to iteratively retrieve the gradient and + * solid fill information for colored glyph layers for a specified glyph + * ID. + * + * https://github.com/googlefonts/colr-gradients-spec + * + * @input: + * face :: + * A handle to the parent face object. + * + * @inout: + * iterator :: + * The retrieved @FT_ColorStopIterator, configured on an @FT_ColorLine, + * which in turn got retrieved via paint information in + * @FT_PaintLinearGradient or @FT_PaintRadialGradient. + * + * @output: + * color_stop :: + * Color index and alpha value for the retrieved color stop. + * + * @return: + * Value~1 if everything is OK. If there are no more color stops, + * value~0 gets returned. In case of an error, value~0 is returned + * also. + * + * @since: + * 2.13 + */ + FT_EXPORT( FT_Bool ) + FT_Get_Colorline_Stops( FT_Face face, + FT_ColorStop* color_stop, + FT_ColorStopIterator* iterator ); + + + /************************************************************************** + * + * @function: + * FT_Get_Paint + * + * @description: + * Access the details of a paint using an @FT_OpaquePaint opaque paint + * object, which internally stores the offset to the respective `Paint` + * object in the 'COLR' table. + * + * @input: + * face :: + * A handle to the parent face object. + * + * opaque_paint :: + * The opaque paint object for which the underlying @FT_COLR_Paint + * data is to be retrieved. + * + * @output: + * paint :: + * The specific @FT_COLR_Paint object containing information coming + * from one of the font's `Paint*` tables. + * + * @return: + * Value~1 if everything is OK. Value~0 if no details can be found for + * this paint or any other error occured. + * + * @since: + * 2.13 + */ + FT_EXPORT( FT_Bool ) + FT_Get_Paint( FT_Face face, + FT_OpaquePaint opaque_paint, + FT_COLR_Paint* paint ); + /* */ |