Geometry API

Geometries, paths, and transformations.

Blend2D offers various geometry structures and objects that can be used with either BLPath for path building or BLContext for rendering.

Classes

struct BLPointI

struct BLSizeI

struct BLBoxI

struct BLRectI

struct BLPoint

struct BLSize

struct BLBox

struct BLRect

struct BLLine

struct BLTriangle

struct BLRoundRect

struct BLCircle

struct BLEllipse

struct BLArc

struct BLMatrix2D

struct BLApproximationOptions

struct BLStrokeOptionsCore

class BLStrokeOptions

struct BLPathView

struct BLPathImpl

struct BLPathCore

class BLPath

struct BLRegionImpl

struct BLRegionCore

class BLRegion

Typedefs

typedef BLResult(* BLPathSinkFunc)(BLPathCore* path, const void* info, void* closure)

typedef BLResult(* BLMapPointDArrayFunc)(const void* ctx, BLPoint* dst, const BLPoint* src, size_t count)

Enumerations

enum BLGeometryDirection : uint32_t

enum BLGeometryType : uint32_t

enum BLFillRule : uint32_t

enum BLHitTest : uint32_t

enum BLMatrix2DType : uint32_t

enum BLMatrix2DValue : uint32_t

enum BLMatrix2DOp : uint32_t

enum BLPathCmd : uint32_t

enum BLPathCmdExtra : uint32_t

enum BLPathFlags : uint32_t

enum BLPathReverseMode : uint32_t

enum BLStrokeJoin : uint32_t

enum BLStrokeCapPosition : uint32_t

enum BLStrokeCap : uint32_t

enum BLStrokeTransformOrder : uint32_t

enum BLFlattenMode : uint32_t

enum BLOffsetMode : uint32_t

enum BLRegionType : uint32_t

Variables

BLMapPointDArrayFunc blMatrix2DMapPointDArrayFuncs[BL_MATRIX2D_TYPE_COUNT]

const BLApproximationOptions blDefaultApproximationOptions

Global Specializations

template<>

constexpr BLPoint blAbs(const BLPoint& a)

template<>

constexpr BLPoint blMin(const BLPoint& a, const BLPoint& b)

template<>

constexpr BLPoint blMax(const BLPoint& a, const BLPoint& b)

template<>

constexpr BLSize blAbs(const BLSize& a)

template<>

constexpr BLSize blMin(const BLSize& a, const BLSize& b)

template<>

constexpr BLSize blMax(const BLSize& a, const BLSize& b)

static constexpr BLPoint blMin(const BLPoint& a, double b)

static constexpr BLPoint blMin(double a, const BLPoint& b)

static constexpr BLPoint blMax(const BLPoint& a, double b)

static constexpr BLPoint blMax(double a, const BLPoint& b)

static constexpr BLPoint blClamp(const BLPoint& a, double b, double c)

Overloaded Operators

static constexpr BLPointI operator-(const BLPointI& self)

static constexpr BLPointI operator+(const BLPointI& a, int b)

static constexpr BLPointI operator-(const BLPointI& a, int b)

static constexpr BLPointI operator*(const BLPointI& a, int b)

static constexpr BLPointI operator+(int a, const BLPointI& b)

static constexpr BLPointI operator-(int a, const BLPointI& b)

static constexpr BLPointI operator*(int a, const BLPointI& b)

static constexpr BLPointI operator+(const BLPointI& a, const BLPointI& b)

static constexpr BLPointI operator-(const BLPointI& a, const BLPointI& b)

static constexpr BLPointI operator*(const BLPointI& a, const BLPointI& b)

static BLPointI& operator+=(BLPointI& a, int b)

static BLPointI& operator-=(BLPointI& a, int b)

static BLPointI& operator*=(BLPointI& a, int b)

static BLPointI& operator/=(BLPointI& a, int b)

static BLPointI& operator+=(BLPointI& a, const BLPointI& b)

static BLPointI& operator-=(BLPointI& a, const BLPointI& b)

static BLPointI& operator*=(BLPointI& a, const BLPointI& b)

static BLPointI& operator/=(BLPointI& a, const BLPointI& b)

static constexpr BLPoint operator-(const BLPoint& a)

static constexpr BLPoint operator+(const BLPoint& a, double b)

static constexpr BLPoint operator-(const BLPoint& a, double b)

static constexpr BLPoint operator*(const BLPoint& a, double b)

static constexpr BLPoint operator/(const BLPoint& a, double b)

static constexpr BLPoint operator+(double a, const BLPoint& b)

static constexpr BLPoint operator-(double a, const BLPoint& b)

static constexpr BLPoint operator*(double a, const BLPoint& b)

static constexpr BLPoint operator/(double a, const BLPoint& b)

static constexpr BLPoint operator+(const BLPoint& a, const BLPoint& b)

static constexpr BLPoint operator-(const BLPoint& a, const BLPoint& b)

static constexpr BLPoint operator*(const BLPoint& a, const BLPoint& b)

static constexpr BLPoint operator/(const BLPoint& a, const BLPoint& b)

static BLPoint& operator+=(BLPoint& a, double b)

static BLPoint& operator-=(BLPoint& a, double b)

static BLPoint& operator*=(BLPoint& a, double b)

static BLPoint& operator/=(BLPoint& a, double b)

static BLPoint& operator+=(BLPoint& a, const BLPoint& b)

static BLPoint& operator-=(BLPoint& a, const BLPoint& b)

static BLPoint& operator*=(BLPoint& a, const BLPoint& b)

static BLPoint& operator/=(BLPoint& a, const BLPoint& b)

static BLBox operator+(double a, const BLBox& b)

static BLBox operator-(double a, const BLBox& b)

static BLBox operator*(double a, const BLBox& b)

static BLBox operator/(double a, const BLBox& b)

static BLBox operator+(const BLBox& a, double b)

static BLBox operator-(const BLBox& a, double b)

static BLBox operator*(const BLBox& a, double b)

static BLBox operator/(const BLBox& a, double b)

static BLBox operator+(const BLPoint& a, const BLBox& b)

static BLBox operator-(const BLPoint& a, const BLBox& b)

static BLBox operator*(const BLPoint& a, const BLBox& b)

static BLBox operator/(const BLPoint& a, const BLBox& b)

static BLBox operator+(const BLBox& a, const BLPoint& b)

static BLBox operator-(const BLBox& a, const BLPoint& b)

static BLBox operator*(const BLBox& a, const BLPoint& b)

static BLBox operator/(const BLBox& a, const BLPoint& b)

static BLBox& operator+=(BLBox& a, double b)

static BLBox& operator-=(BLBox& a, double b)

static BLBox& operator*=(BLBox& a, double b)

static BLBox& operator/=(BLBox& a, double b)

static BLBox& operator+=(BLBox& a, const BLPoint& b)

static BLBox& operator-=(BLBox& a, const BLPoint& b)

static BLBox& operator*=(BLBox& a, const BLPoint& b)

static BLBox& operator/=(BLBox& a, const BLPoint& b)

Typedef Documentation

typedef BLResult(* BLPathSinkFunc)(BLPathCore* path, const void* info, void* closure)

Optional callback that can be used to consume a path data.

typedef BLResult(* BLMapPointDArrayFunc)(const void* ctx, BLPoint* dst, const BLPoint* src, size_t count)

A generic function that can be used to transform an array of points that use double precision coordinates. This function will be 99.99% of time used with BLMatrix2D so the ctx would point to a const BLMatrix2D* instance.

Enumeration Type Documentation

BLGeometryDirection : uint32_tenum

Direction of a geometry used by geometric primitives and paths.

Constant	Description
BL_GEOMETRY_DIRECTION_NONE	No direction specified.
BL_GEOMETRY_DIRECTION_CW	Clockwise direction.
BL_GEOMETRY_DIRECTION_CCW	Counter-clockwise direction.

BLGeometryType : uint32_tenum

Geometry type.

Geometry describes a shape or path that can be either rendered or added to a BLPath container. Both BLPath and BLContext provide functionality to work with all geometry types. Please note that each type provided here requires to pass a matching struct or class to the function that consumes a geometryType and geometryData arguments.

Constant	Description
BL_GEOMETRY_TYPE_NONE	No geometry provided.
BL_GEOMETRY_TYPE_BOXI	BLBoxI struct.
BL_GEOMETRY_TYPE_BOXD	BLBox struct.
BL_GEOMETRY_TYPE_RECTI	BLRectI struct.
BL_GEOMETRY_TYPE_RECTD	BLRect struct.
BL_GEOMETRY_TYPE_CIRCLE	BLCircle struct.
BL_GEOMETRY_TYPE_ELLIPSE	BLEllipse struct.
BL_GEOMETRY_TYPE_ROUND_RECT	BLRoundRect struct.
BL_GEOMETRY_TYPE_ARC	BLArc struct.
BL_GEOMETRY_TYPE_CHORD	BLArc struct representing chord.
BL_GEOMETRY_TYPE_PIE	BLArc struct representing pie.
BL_GEOMETRY_TYPE_LINE	BLLine struct.
BL_GEOMETRY_TYPE_TRIANGLE	BLTriangle struct.
BL_GEOMETRY_TYPE_POLYLINEI	BLArrayView<BLPointI> representing a polyline.
BL_GEOMETRY_TYPE_POLYLINED	BLArrayView<BLPoint> representing a polyline.
BL_GEOMETRY_TYPE_POLYGONI	BLArrayView<BLPointI> representing a polygon.
BL_GEOMETRY_TYPE_POLYGOND	BLArrayView<BLPoint> representing a polygon.
BL_GEOMETRY_TYPE_ARRAY_VIEW_BOXI	BLArrayView<BLBoxI> struct.
BL_GEOMETRY_TYPE_ARRAY_VIEW_BOXD	BLArrayView<BLBox> struct.
BL_GEOMETRY_TYPE_ARRAY_VIEW_RECTI	BLArrayView<BLRectI> struct.
BL_GEOMETRY_TYPE_ARRAY_VIEW_RECTD	BLArrayView<BLRect> struct.
BL_GEOMETRY_TYPE_PATH	BLPath (or BLPathCore).
BL_GEOMETRY_TYPE_REGION	BLRegion (or BLRegionCore).
BL_GEOMETRY_TYPE_COUNT	Count of geometry types.

BLFillRule : uint32_tenum

Fill rule.

Constant	Description
BL_FILL_RULE_NON_ZERO	Non-zero fill-rule.
BL_FILL_RULE_EVEN_ODD	Even-odd fill-rule.
BL_FILL_RULE_COUNT	Count of fill rule types.

BLHitTest : uint32_tenum

Hit-test result.

Constant	Description
BL_HIT_TEST_IN	Fully in. Partially in/out.
BL_HIT_TEST_PART	Fully out.
BL_HIT_TEST_OUT	Hit test failed (invalid argument, NaNs, etc).

BLMatrix2DType : uint32_tenum

2D matrix type that can be obtained by calling BLMatrix2D::type().

Identity  Transl.  Scale     Swap    Affine
 [1  0]   [1  0]   [.  0]   [0  .]   [.  .]
 [0  1]   [0  1]   [0  .]   [.  0]   [.  .]
 [0  0]   [.  .]   [.  .]   [.  .]   [.  .]

Constant	Description
BL_MATRIX2D_TYPE_IDENTITY	Identity matrix.
BL_MATRIX2D_TYPE_TRANSLATE	Has translation part (the rest is like identity).
BL_MATRIX2D_TYPE_SCALE	Has translation and scaling parts.
BL_MATRIX2D_TYPE_SWAP	Has translation and scaling parts, however scaling swaps X/Y.
BL_MATRIX2D_TYPE_AFFINE	Generic affine matrix.
BL_MATRIX2D_TYPE_INVALID	Invalid/degenerate matrix not useful for transformations.
BL_MATRIX2D_TYPE_COUNT	Count of matrix types.

BLMatrix2DValue : uint32_tenum

2D matrix data index.

Constant	Description
BL_MATRIX2D_VALUE_00	Value at index 0 - M00.
BL_MATRIX2D_VALUE_01	Value at index 1 - M01.
BL_MATRIX2D_VALUE_10	Value at index 2 - M10.
BL_MATRIX2D_VALUE_11	Value at index 3 - M11.
BL_MATRIX2D_VALUE_20	Value at index 4 - M20.
BL_MATRIX2D_VALUE_21	Value at index 5 - M21.
BL_MATRIX2D_VALUE_COUNT	Count of BLMatrix2D values.

BLMatrix2DOp : uint32_tenum

2D matrix operation.

Constant	Description
BL_MATRIX2D_OP_RESET	Reset matrix to identity (argument ignored, should be nullptr).
BL_MATRIX2D_OP_ASSIGN	Assign (copy) the other matrix.
BL_MATRIX2D_OP_TRANSLATE	Translate the matrix by [x, y].
BL_MATRIX2D_OP_SCALE	Scale the matrix by [x, y].
BL_MATRIX2D_OP_SKEW	Skew the matrix by [x, y].
BL_MATRIX2D_OP_ROTATE	Rotate the matrix by the given angle about [0, 0].
BL_MATRIX2D_OP_ROTATE_PT	Rotate the matrix by the given angle about [x, y].
BL_MATRIX2D_OP_TRANSFORM	Transform this matrix by other BLMatrix2D.
BL_MATRIX2D_OP_POST_TRANSLATE	Post-translate the matrix by [x, y].
BL_MATRIX2D_OP_POST_SCALE	Post-scale the matrix by [x, y].
BL_MATRIX2D_OP_POST_SKEW	Post-skew the matrix by [x, y].
BL_MATRIX2D_OP_POST_ROTATE	Post-rotate the matrix about [0, 0].
BL_MATRIX2D_OP_POST_ROTATE_PT	Post-rotate the matrix about a reference BLPoint.
BL_MATRIX2D_OP_POST_TRANSFORM	Post-transform this matrix by other BLMatrix2D.
BL_MATRIX2D_OP_COUNT	Count of matrix operations.

BLPathCmd : uint32_tenum

Path command.

Constant	Description
BL_PATH_CMD_MOVE	Move-to command (starts a new figure).
BL_PATH_CMD_ON	On-path command (interpreted as line-to or the end of a curve).
BL_PATH_CMD_QUAD	Quad-to control point.
BL_PATH_CMD_CUBIC	Cubic-to control point (always used as a pair of commands).
BL_PATH_CMD_CLOSE	Close path.
BL_PATH_CMD_COUNT	Count of path commands.

BLPathCmdExtra : uint32_tenum

Path command (never stored in path).

Constant	Description
BL_PATH_CMD_PRESERVE	Used by BLPath::setVertexAt to preserve the current command value.

BLPathFlags : uint32_tenum

Path flags.

Constant	Description
BL_PATH_FLAG_EMPTY	Path is empty (no commands or close commands only).
BL_PATH_FLAG_MULTIPLE	Path contains multiple figures.
BL_PATH_FLAG_QUADS	Path contains quad curves (at least one).
BL_PATH_FLAG_CUBICS	Path contains cubic curves (at least one).
BL_PATH_FLAG_INVALID	Path is invalid.
BL_PATH_FLAG_DIRTY	Flags are dirty (not reflecting the current status).

BLPathReverseMode : uint32_tenum

Path reversal mode.

Constant	Description
BL_PATH_REVERSE_MODE_COMPLETE	Reverse each figure and their order as well (default).
BL_PATH_REVERSE_MODE_SEPARATE	Reverse each figure separately (keeps their order).
BL_PATH_REVERSE_MODE_COUNT	Count of path-reversal modes.

BLStrokeJoin : uint32_tenum

Stroke join type.

Constant	Description
BL_STROKE_JOIN_MITER_CLIP	Miter-join possibly clipped at miterLimit [default].
BL_STROKE_JOIN_MITER_BEVEL	Miter-join or bevel-join depending on miterLimit condition.
BL_STROKE_JOIN_MITER_ROUND	Miter-join or round-join depending on miterLimit condition.
BL_STROKE_JOIN_BEVEL	Bevel-join.
BL_STROKE_JOIN_ROUND	Round-join.
BL_STROKE_JOIN_COUNT	Count of stroke join types.

BLStrokeCapPosition : uint32_tenum

Position of a stroke-cap.

Constant	Description
BL_STROKE_CAP_POSITION_START	Start of the path.
BL_STROKE_CAP_POSITION_END	End of the path.
BL_STROKE_CAP_POSITION_COUNT	Count of stroke position options.

BLStrokeCap : uint32_tenum

A presentation attribute defining the shape to be used at the end of open subpaths.

Constant	Description
BL_STROKE_CAP_BUTT	Butt cap [default].
BL_STROKE_CAP_SQUARE	Square cap.
BL_STROKE_CAP_ROUND	Round cap.
BL_STROKE_CAP_ROUND_REV	Round cap reversed.
BL_STROKE_CAP_TRIANGLE	Triangle cap.
BL_STROKE_CAP_TRIANGLE_REV	Triangle cap reversed.
BL_STROKE_CAP_COUNT	Used to catch invalid arguments.

BLStrokeTransformOrder : uint32_tenum

Stroke transform order.

Constant	Description
BL_STROKE_TRANSFORM_ORDER_AFTER	Transform after stroke => Transform(Stroke(Input)) [default].
BL_STROKE_TRANSFORM_ORDER_BEFORE	Transform before stroke => Stroke(Transform(Input)).
BL_STROKE_TRANSFORM_ORDER_COUNT	Count of transform order types.

BLFlattenMode : uint32_tenum

Mode that specifies how curves are approximated to line segments.

Constant	Description
BL_FLATTEN_MODE_DEFAULT	Use default mode (decided by Blend2D).
BL_FLATTEN_MODE_RECURSIVE	Recursive subdivision flattening.
BL_FLATTEN_MODE_COUNT	Count of flatten modes.

BLOffsetMode : uint32_tenum

Mode that specifies how to construct offset curves.

Constant	Description
BL_OFFSET_MODE_DEFAULT	Use default mode (decided by Blend2D).
BL_OFFSET_MODE_ITERATIVE	Iterative offset construction.
BL_OFFSET_MODE_COUNT	Count of offset modes.

BLRegionType : uint32_tenum

Region type.

Constant	Description
BL_REGION_TYPE_EMPTY	Region is empty (has no rectangles).
BL_REGION_TYPE_RECT	Region has one rectangle (rectangular).
BL_REGION_TYPE_COMPLEX	Region has more YX sorted rectangles.
BL_REGION_TYPE_COUNT	Count of region types.

Variable Documentation

BLMapPointDArrayFunc blMatrix2DMapPointDArrayFuncs[BL_MATRIX2D_TYPE_COUNT]

Array of functions for transforming points indexed by BLMatrixType. Each function is optimized for the respective type. This is mostly used internally, but exported for users that can take advantage of Blend2D SIMD optimziations.

const BLApproximationOptions blDefaultApproximationOptions

Default approximation options used by Blend2D.