Data Structures
struct	gdPathMatrixStruct
	Affine transformation matrix. More...

struct	gdRectFStruct
	Floating-point rectangle. More...

struct	gdTextError
	Optional detailed error information for 2D text APIs. More...

struct	gdTextExtents

struct	gdTextOptions

Typedefs
typedef struct gdContextStruct	gdContext
	Opaque 2D drawing context.

typedef gdContext *	gdContextPtr
	Opaque 2D drawing context pointer.

typedef struct gdPathStruct	gdPath
	Opaque text shaping options.

typedef gdPath *	gdPathPtr
	Opaque vector path pointer.

typedef struct gdPaintStruct	gdPaint
	Opaque paint source.

typedef gdPaint *	gdPaintPtr
	Opaque paint source pointer.

typedef struct gdPathPatternStruct	gdPathPattern
	Opaque image pattern.

typedef gdPathPattern *	gdPathPatternPtr
	Opaque image pattern pointer.

typedef struct gdFontFaceStruct	gdFontFace
	Opaque font face.

typedef gdFontFace *	gdFontFacePtr
	Opaque font face pointer.

typedef struct gdPathMatrixStruct	gdPathMatrix
	Affine transformation matrix.

typedef gdPathMatrix *	gdPathMatrixPtr
	Affine transformation matrix pointer.

typedef struct gdRectFStruct	gdRectF
	Floating-point rectangle.

typedef gdRectF *	gdRectFPtr
	Floating-point rectangle pointer.

Enumerations
enum	gdExtendMode

enum	gdLineCap { gdLineCapButt , gdLineCapRound , gdLineCapSquare }

enum	gdLineJoin { gdLineJoinMiter , gdLineJoinRound , gdLineJoinBevel }

enum	gdFillRule { gdFillRuleNonZero , gdFillRuleEvenOdd }

enum	gdPatternFilter { GD_PATTERN_FILTER_FAST , GD_PATTERN_FILTER_GOOD , GD_PATTERN_FILTER_BEST }

enum	gdCompositeOperator { GD_OP_CLEAR , GD_OP_SOURCE , GD_OP_OVER , GD_OP_IN , GD_OP_OUT , GD_OP_ATOP , GD_OP_DEST , GD_OP_DEST_OVER , GD_OP_DEST_IN , GD_OP_DEST_OUT , GD_OP_DEST_ATOP , GD_OP_XOR , GD_OP_ADD , GD_OP_SATURATE , GD_OP_MULTIPLY , GD_OP_SCREEN , GD_OP_OVERLAY , GD_OP_DARKEN , GD_OP_LIGHTEN , GD_OP_COLOR_DODGE , GD_OP_COLOR_BURN , GD_OP_HARD_LIGHT , GD_OP_SOFT_LIGHT , GD_OP_DIFFERENCE , GD_OP_EXCLUSION , GD_OP_HSL_HUE , GD_OP_HSL_SATURATION , GD_OP_HSL_COLOR , GD_OP_HSL_LUMINOSITY , GD_OP_COUNT }

enum	gdTextStatus { GD_TEXT_OK = 0 , GD_TEXT_E_INVALID_ARGUMENT , GD_TEXT_E_UNAVAILABLE , GD_TEXT_E_FONT , GD_TEXT_E_LAYOUT , GD_TEXT_E_MEMORY }

enum	gdTextShaping { GD_TEXT_SHAPING_NONE = 0 , GD_TEXT_SHAPING_RAQM = 1 }

Functions
int	gdImageComposite (gdImagePtr dst, const gdImagePtr src, int dst_x, int dst_y, gdCompositeOperator op, double opacity, gdRectPtr src_region, gdRectPtr clip)
	Composite a source image into a truecolor destination image.

void	gdTextOptionsInit (gdTextOptions *options)
	Initialize text options to defaults.

gdContextPtr	gdContextCreateForImage (gdImagePtr image)
	Create a 2D drawing context for a truecolor image.

void	gdContextFlushImage (gdContextPtr context)
	Copy the context's drawing surface back into its image.

int	gdContextReloadImage (gdContextPtr context)
	Reload the context drawing surface from its backing image.

gdImagePtr	gdContextGetImage (gdContextPtr context)
	Get the image associated with a context.

void	gdContextDestroy (gdContextPtr context)
	Destroy a context and flush drawing changes to the backing image.

void	gdContextDestroyNoFlush (gdContextPtr context)
	Destroy a context without flushing drawing changes to the backing image.

int	gdContextSave (gdContextPtr context)
	Save the current graphics state.

int	gdContextRestore (gdContextPtr context)
	Restore the most recently saved graphics state.

int	gdContextClip (gdContextPtr context)
	Intersect the current clip with the current path and clear the path.

int	gdContextClipPreserve (gdContextPtr context)
	Intersect the current clip with the current path without clearing the path.

void	gdContextNewPath (gdContextPtr context)
	Clear the current path.

void	gdContextAppendPath (gdContextPtr context, gdPathPtr path)
	Append a path to the context's current path.

void	gdContextSetSourceRgba (gdContextPtr context, double r, double g, double b, double a)
	Set the current source paint to a solid RGBA color.

void	gdContextSetSourceRgb (gdContextPtr context, double r, double g, double b)
	Set the current source paint to an opaque RGB color.

void	gdContextSetSourceImage (gdContextPtr context, gdImagePtr image, double x, double y)
	Set the current source paint to an image pattern.

void	gdContextSetSource (gdContextPtr context, gdPaintPtr source)
	Set the current source paint.

void	gdContextSetOperator (gdContextPtr context, gdCompositeOperator op)
	Set the compositing operator used for subsequent drawing.

void	gdContextSetOpacity (gdContextPtr context, double opacity)
	Set a global opacity multiplier for subsequent drawing.

void	gdContextSetPatternFilter (gdContextPtr context, gdPatternFilter filter)
	Set the default image-pattern filter for patterns created by context source helpers such as gdContextSetSourceImage.

gdPatternFilter	gdContextGetPatternFilter (gdContextPtr context)
	Get the current default image-pattern filter from a context.

void	gdContextSetFontFace (gdContextPtr context, gdFontFacePtr face)
	Set the current font face for text operations.

void	gdContextSetFontSize (gdContextPtr context, double size)
	Set the current font size for text operations.

gdTextStatus	gdContextTextPath (gdContextPtr context, const char utf8, double x, double y, const gdTextOptions options, gdTextError *err)
	Convert UTF-8 text to path contours and append them to the current path.

gdTextStatus	gdContextShowText (gdContextPtr context, const char utf8, double x, double y, const gdTextOptions options, gdTextError *err)
	Draw UTF-8 text using the current source paint.

gdTextStatus	gdContextTextExtents (gdContextPtr context, const char utf8, const gdTextOptions options, gdTextExtents extents, gdTextError err)
	Measure UTF-8 text using the current font face and font size.

void	gdContextMoveTo (gdContextPtr context, double x, double y)
	Move the current point in the context path.

void	gdContextRelMoveTo (gdContextPtr context, double dx, double dy)
	Move the current point by an offset in the context path.

void	gdContextLineTo (gdContextPtr context, double x, double y)
	Add a line to the context path.

void	gdContextRelLineTo (gdContextPtr context, double dx, double dy)
	Add a relative line to the context path.

void	gdContextCurveTo (gdContextPtr context, double x1, double y1, double x2, double y2, double x3, double y3)
	Add a cubic Bezier curve to the context path.

void	gdContextRelCurveTo (gdContextPtr context, double dx1, double dy1, double dx2, double dy2, double dx3, double dy3)
	Add a relative cubic Bezier curve to the context path.

void	gdContextQuadTo (gdContextPtr context, double x1, double y1, double x2, double y2)
	Add a quadratic Bezier curve to the context path.

void	gdContextRelQuadTo (gdContextPtr context, double dx1, double dy1, double dx2, double dy2)
	Add a relative quadratic Bezier curve to the context path.

void	gdContextArc (gdContextPtr context, double cx, double cy, double radius, double a0, double a1)
	Add a positive-direction circular arc to the context path.

void	gdContextNegativeArc (gdContextPtr context, double cx, double cy, double radius, double a0, double a1)
	Add a negative-direction circular arc to the context path.

void	gdContextRectangle (gdContextPtr context, double x, double y, double width, double height)
	Add a rectangle to the context path.

void	gdContextClosePath (gdContextPtr context)
	Close the current contour in the context path.

void	gdContextScale (gdContextPtr context, double x, double y)
	Apply scaling to the current transformation matrix.

void	gdContextTranslate (gdContextPtr context, double x, double y)
	Apply translation to the current transformation matrix.

void	gdContextRotate (gdContextPtr context, double radians)
	Apply rotation to the current transformation matrix.

void	gdContextTransform (gdContextPtr context, const gdPathMatrixPtr matrix)
	Apply an affine transformation to the current transformation matrix.

void	gdContextSetLineWidth (gdContextPtr context, double width)
	Set the stroke line width.

void	gdContextSetLineCap (gdContextPtr context, gdLineCap cap)
	Set the stroke line cap style.

void	gdContextSetLineJoin (gdContextPtr context, gdLineJoin join)
	Set the stroke line join style.

void	gdContextSetDash (gdContextPtr context, double offset, const double *data, int size)
	Set the stroke dash pattern.

void	gdContextSetFillRule (gdContextPtr context, gdFillRule rule)
	Set the fill rule used by subsequent fill and clip operations.

void	gdContextStroke (gdContextPtr context)
	Stroke the current path and then clear it.

void	gdContextStrokePreserve (gdContextPtr context)
	Stroke the current path without clearing it.

void	gdContextFill (gdContextPtr context)
	Fill the current path and then clear it.

void	gdContextFillPreserve (gdContextPtr context)
	Fill the current path without clearing it.

void	gdContextPaint (gdContextPtr context)
	Paint the current source over the entire current clip.

gdFontFacePtr	gdFontFaceCreateFromFile (const char path, int face_index, gdTextError err)
	Load a font face from a file.

gdFontFacePtr	gdFontFaceCreateFromData (const unsigned char data, size_t size, int face_index, gdTextError err)
	Load a font face from memory.

gdFontFacePtr	gdFontFaceAddRef (gdFontFacePtr face)
	Add a reference to a font face.

void	gdFontFaceDestroy (gdFontFacePtr face)
	Release a font face reference. Passing NULL has no effect.

gdPaintPtr	gdPaintCreateFromPattern (gdPathPatternPtr pattern)
	Create a paint object from an image pattern.

gdPaintPtr	gdPaintCreateLinear (double x0, double y0, double x1, double y1)
	Create a linear gradient paint.

gdPaintPtr	gdPaintCreateRadial (double x0, double y0, double r0, double x1, double y1, double r1)
	Create a radial gradient paint between two circles.

int	gdPaintAddColorStopRgb (gdPaintPtr paint, double offset, double r, double g, double b)
	Add an opaque color stop to a gradient paint.

int	gdPaintAddColorStopRgba (gdPaintPtr paint, double offset, double r, double g, double b, double a)
	Add a color stop with opacity to a gradient paint.

int	gdPaintSetExtend (gdPaintPtr paint, gdExtendMode extend)
	Set the extend mode for a gradient or pattern paint.

int	gdPaintSetMatrix (gdPaintPtr paint, const gdPathMatrixPtr matrix)
	Set the paint's pattern or gradient transform.

void	gdPaintDestroy (gdPaintPtr paint)
	Release a paint object. Passing NULL has no effect.

gdPathPatternPtr	gdPathPatternCreateForImage (gdImagePtr image)
	Create an image pattern from a gd image.

void	gdPathPatternDestroy (gdPathPatternPtr pattern)
	Release a pattern object. Passing NULL has no effect.

void	gdPathPatternSetExtend (gdPathPatternPtr pattern, gdExtendMode extend)
	Set how an image pattern is sampled outside its image bounds.

void	gdPathPatternSetMatrix (gdPathPatternPtr pattern, gdPathMatrixPtr matrix)
	Set the pattern-to-user-space transform for an image pattern.

void	gdPathPatternSetOpacity (gdPathPatternPtr pattern, double opacity)
	Set the opacity multiplier for an image pattern.

void	gdPathPatternSetFilter (gdPathPatternPtr pattern, gdPatternFilter filter)
	Set the sampling quality for an image pattern.

gdPatternFilter	gdPathPatternGetFilter (gdPathPatternPtr pattern)
	Get the sampling quality for an image pattern.

void	gdPathMatrixInit (gdPathMatrixPtr matrix, double m00, double m10, double m01, double m11, double m02, double m12)
	Initialize an affine transformation matrix from its six coefficients.

void	gdPathMatrixInitIdentity (gdPathMatrixPtr matrix)
	Initialize a matrix to the identity transformation.

void	gdPathMatrixInitTranslate (gdPathMatrixPtr matrix, double x, double y)
	Initialize a translation matrix.

void	gdPathMatrixInitScale (gdPathMatrixPtr matrix, double x, double y)
	Initialize a scaling matrix.

void	gdPathMatrixInitShear (gdPathMatrixPtr matrix, double x, double y)
	Initialize a shear matrix. The shear factors are the tangents of the supplied angles.

void	gdPathMatrixInitRotate (gdPathMatrixPtr matrix, double radians)
	Initialize a rotation matrix about the origin.

void	gdPathMatrixInitRotateTranslate (gdPathMatrixPtr matrix, double radians, double x, double y)
	Initialize a rotation matrix about a specified point. The point (x, y) remains unchanged by the resulting transformation.

void	gdPathMatrixTranslate (gdPathMatrixPtr matrix, double x, double y)
	Apply a translation before the transformation already in a matrix.

void	gdPathMatrixScale (gdPathMatrixPtr matrix, double x, double y)
	Apply scaling before the transformation already in a matrix.

void	gdPathMatrixShear (gdPathMatrixPtr matrix, double x, double y)
	Apply a shear before the transformation already in a matrix.

void	gdPathMatrixRotate (gdPathMatrixPtr matrix, double radians)
	Apply a rotation about the origin before the transformation already in a matrix.

void	gdPathMatrixRotateTranslate (gdPathMatrixPtr matrix, double radians, double x, double y)
	Apply a rotation about a specified point before the transformation already in a matrix.

void	gdPathMatrixMultiply (gdPathMatrixPtr matrix, const gdPathMatrixPtr a, const gdPathMatrixPtr b)
	Compose two affine transformations. The result maps through a first and then through b. matrix may alias a or b.

int	gdPathMatrixInvert (gdPathMatrixPtr matrix)
	Invert an affine transformation in place. A singular matrix is left unchanged.

void	gdPathMatrixMap (const gdPathMatrixPtr matrix, double x, double y, double result_x, double result_y)
	Transform a pair of coordinates.

void	gdPathMatrixMapPoint (const gdPathMatrixPtr matrix, const gdPointFPtr src, gdPointFPtr dst)
	Transform a point. src and dst may point to the same object.

void	gdPathMatrixMapRect (const gdPathMatrixPtr matrix, const gdRectFPtr src, gdRectFPtr dst)
	Transform all four corners of a rectangle and calculate their axis-aligned bounding box. src and dst may point to the same object.

gdPathPtr	gdPathCreate (void)
	Create an empty path.

gdPathPtr	gdPathDuplicate (const gdPathPtr path)
	Create an independent copy of a path.

void	gdPathDestroy (gdPathPtr path)
	Release a path. Passing NULL has no effect.

void	gdPathAppendPath (gdPathPtr path, const gdPathPtr source)
	Append all contours from one path to another.

void	gdPathTransform (gdPathPtr path, const gdPathMatrixPtr matrix)
	Transform every point in a path in place.

void	gdPathMoveTo (gdPathPtr path, double x, double y)
	Start a new contour at an absolute position.

void	gdPathRelMoveTo (gdPathPtr path, double dx, double dy)
	Start a new contour at an offset from the current point. For an empty path, the offset is relative to (0, 0).

void	gdPathLineTo (gdPathPtr path, double x, double y)
	Add a straight line to an absolute position.

void	gdPathRelLineTo (gdPathPtr path, double dx, double dy)
	Add a straight line using an offset from the current point.

void	gdPathQuadTo (gdPathPtr path, double x1, double y1, double x2, double y2)
	Add a quadratic Bezier curve.

void	gdPathRelQuadTo (gdPathPtr path, double dx1, double dy1, double dx2, double dy2)
	Add a quadratic Bezier curve using offsets from the current point.

void	gdPathCurveTo (gdPathPtr path, double x1, double y1, double x2, double y2, double x3, double y3)
	Add a cubic Bezier curve.

void	gdPathRelCurveTo (gdPathPtr path, double dx1, double dy1, double dx2, double dy2, double dx3, double dy3)
	Add a cubic Bezier curve using offsets from the current point.

void	gdPathArc (gdPathPtr path, double cx, double cy, double radius, double angle1, double angle2)
	Add a circular arc in the positive-angle direction. Angles are in radians. A line is added from the current point to the beginning of the arc when necessary.

void	gdPathNegativeArc (gdPathPtr path, double cx, double cy, double radius, double angle1, double angle2)
	Add a circular arc in the negative-angle direction. Angles are in radians. A line is added from the current point to the beginning of the arc when necessary.

void	gdPathArcTo (gdPathPtr path, double x1, double y1, double x2, double y2, double radius)
	Connect the current point to (x1, y1) and (x2, y2) with a circular arc tangent to both line segments. Degenerate geometry or a non-positive radius adds a line to (x1, y1).

void	gdPathRectangle (gdPathPtr path, double x, double y, double width, double height)
	Add a closed rectangular contour.

void	gdPathClose (gdPathPtr path)
	Close the current contour with a line to its starting point. An empty path or an already closed contour is unchanged.

Detailed Description

Experimental 2D vector drawing API for libgd.

Typedef Documentation

◆ gdContext

typedef struct gdContextStruct gdContext

Opaque 2D drawing context.

Opaque drawing context for the 2D API. A context owns the current path and a stack of graphics state, and draws into an ARGB surface backed by a truecolor gdImage.

See also:

See also
gdContextCreateForImage
See also
gdContextDestroy

◆ gdContextPtr

typedef gdContext* gdContextPtr

Opaque 2D drawing context pointer.

Pointer to an opaque drawing context for the 2D API.

See also:

See also
gdContext gdContextCreateForImage gdContextDestroy

◆ gdFontFace

typedef struct gdFontFaceStruct gdFontFace

Opaque font face.

Opaque font face used by text APIs.

See also:

See also
gdFontFacePtr gdFontFaceCreateFromFile gdContextSetFontFace

◆ gdFontFacePtr

typedef gdFontFace* gdFontFacePtr

Opaque font face pointer.

Pointer to an opaque font face used by text APIs.

See also:

See also
gdFontFace gdFontFaceCreateFromFile gdContextSetFontFace

◆ gdPaint

typedef struct gdPaintStruct gdPaint

Opaque paint source.

Opaque paint source. A paint may be a solid color, image pattern, or gradient.

See also:

See also
gdContextSetSource gdPaintCreateFromPattern gdPaintCreateLinear

◆ gdPaintPtr

typedef gdPaint* gdPaintPtr

Opaque paint source pointer.

Pointer to an opaque paint source. A paint may be a solid color, image pattern, or gradient.

See also:

See also
gdPaint gdContextSetSource gdPaintCreateFromPattern gdPaintCreateLinear

◆ gdPath

typedef struct gdPathStruct gdPath

Opaque text shaping options.

Opaque vector path made of contours, lines, curves, arcs, and rectangles.

See also:

See also
gdPathPtr gdPathCreate gdContextAppendPath

◆ gdPathMatrix

typedef struct gdPathMatrixStruct gdPathMatrix

Affine transformation matrix.

Affine transformation matrix used by paths, contexts, paints, and patterns.

Points are mapped as: (x * m00 + y * m01 + m02, x * m10 + y * m11 + m12).

See also:

See also
gdPathMatrixPtr gdPathMatrixInit gdContextTransform

◆ gdPathPattern

typedef struct gdPathPatternStruct gdPathPattern

Opaque image pattern.

Opaque image pattern used as a paint source.

See also:

See also
gdPathPatternPtr gdPathPatternCreateForImage gdPathPatternSetFilter

◆ gdPathPatternPtr

typedef gdPathPattern* gdPathPatternPtr

Opaque image pattern pointer.

Pointer to an opaque image pattern used as a paint source.

See also:

See also
gdPathPattern gdPathPatternCreateForImage gdPathPatternSetFilter

◆ gdPathPtr

typedef gdPath* gdPathPtr

Opaque vector path pointer.

Pointer to an opaque vector path made of contours, lines, curves, arcs, and rectangles.

See also:

See also
gdPath gdPathCreate gdContextAppendPath

◆ gdRectF

typedef struct gdRectFStruct gdRectF

Floating-point rectangle.

Members: x - Left coordinate. y - Top coordinate. w - Width. h - Height.

See also
gdRectFPtr

◆ gdRectFPtr

typedef gdRectF* gdRectFPtr

Floating-point rectangle pointer.

Pointer to a floating-point rectangle.

See also
gdRectF

Enumeration Type Documentation

◆ gdCompositeOperator

enum gdCompositeOperator

Constants: gdCompositeOperator

Porter-Duff and blend operators used when painting source pixels over the destination. See also:

See also
gdContextSetOperator

Enumerator
GD_OP_CLEAR	Clear the destination.
GD_OP_SOURCE	Replace with the source.
GD_OP_OVER	Draw source over destination.
GD_OP_IN	Keep source only where destination exists.
GD_OP_OUT	Keep source only where destination is transparent.
GD_OP_ATOP	Source atop destination.
GD_OP_DEST	Keep destination unchanged.
GD_OP_DEST_OVER	Draw destination over source.
GD_OP_DEST_IN	Keep destination only where source exists.
GD_OP_DEST_OUT	Keep destination only where source is transparent.
GD_OP_DEST_ATOP	Destination atop source.
GD_OP_XOR	Source and destination outside their overlap.
GD_OP_ADD	Add source and destination.
GD_OP_SATURATE	Saturating source-over operation.
GD_OP_MULTIPLY	Multiply blend mode.
GD_OP_SCREEN	Screen blend mode.
GD_OP_OVERLAY	Overlay blend mode.
GD_OP_DARKEN	Darken blend mode.
GD_OP_LIGHTEN	Lighten blend mode.
GD_OP_COLOR_DODGE	Color dodge blend mode.
GD_OP_COLOR_BURN	Color burn blend mode.
GD_OP_HARD_LIGHT	Hard light blend mode.
GD_OP_SOFT_LIGHT	Soft light blend mode.
GD_OP_DIFFERENCE	Difference blend mode.
GD_OP_EXCLUSION	Exclusion blend mode.
GD_OP_HSL_HUE	HSL hue blend mode.
GD_OP_HSL_SATURATION	HSL saturation blend mode.
GD_OP_HSL_COLOR	HSL color blend mode.
GD_OP_HSL_LUMINOSITY	HSL luminosity blend mode.

◆ gdExtendMode

enum gdExtendMode

Constants: gdExtendMode

Describes how paints are sampled outside their natural bounds.

See also:

See also
gdPaintSetExtend gdPathPatternSetExtend

◆ gdFillRule

enum gdFillRule

Constants: gdFillRule

Rule used to decide which parts of a path are inside the fill.

See also:

See also
gdContextSetFillRule

Enumerator
gdFillRuleNonZero	Non-zero winding rule.
gdFillRuleEvenOdd	Even-odd rule.

◆ gdLineCap

enum gdLineCap

Constants: gdLineCap

Stroke endpoint style.

See also:

See also
gdContextSetLineCap

Enumerator
gdLineCapButt	End the stroke at the endpoint.
gdLineCapRound	Add a round cap.
gdLineCapSquare	Add a square cap.

◆ gdLineJoin

enum gdLineJoin

Constants: gdLineJoin

Stroke corner style.

See also:

See also
gdContextSetLineJoin

Enumerator
gdLineJoinMiter	Join segments with a miter when possible.
gdLineJoinRound	Join segments with a round corner.
gdLineJoinBevel	Join segments with a bevel.

◆ gdPatternFilter

enum gdPatternFilter

Constants: gdPatternFilter

Selects the image sampling quality used when an image pattern is transformed while filling or painting through the 2D API.

The constants describe the requested quality level, not a fixed low-level kernel. The exact sampler used for GOOD or BEST may change between releases to improve output while keeping the public API stable.

See also: gdContextSetPatternFilter gdPathPatternSetFilter

Enumerator
GD_PATTERN_FILTER_FAST	Fastest sampling. Uses nearest-neighbour sampling.
GD_PATTERN_FILTER_GOOD	Balanced quality. Uses bilinear sampling and mipmapped sampling for minification.
GD_PATTERN_FILTER_BEST	Highest quality. Uses Mitchell bicubic sampling where appropriate and trilinear mipmapped sampling for minification.

◆ gdTextShaping

enum gdTextShaping

Constants: gdTextShaping

Text shaping mode.

See also:

See also
gdTextOptions

Enumerator
GD_TEXT_SHAPING_NONE	Basic glyph loading without complex shaping.
GD_TEXT_SHAPING_RAQM	Use libraqm shaping when available.

◆ gdTextStatus

enum gdTextStatus

Constants: gdTextStatus

Status values returned by 2D text functions.

See also: gdTextError

Enumerator
GD_TEXT_OK	The operation succeeded.
GD_TEXT_E_INVALID_ARGUMENT	An argument was invalid.
GD_TEXT_E_UNAVAILABLE	Required text support is unavailable.
GD_TEXT_E_FONT	A font provider error occurred.
GD_TEXT_E_LAYOUT	Text layout or shaping failed.
GD_TEXT_E_MEMORY	Memory allocation failed.

Function Documentation

◆ gdContextAppendPath()

void gdContextAppendPath	(	gdContextPtr	context,
		gdPathPtr	path
	)

Append a path to the context's current path.

Parameters

context	The drawing context.
path	The path to append.

◆ gdContextClip()

int gdContextClip ( gdContextPtr context )

Intersect the current clip with the current path and clear the path.

Returns: Non-zero on success, zero on allocation failure.

See also:

See also
gdContextClipPreserve

◆ gdContextClipPreserve()

int gdContextClipPreserve ( gdContextPtr context )

Intersect the current clip with the current path without clearing the path.

Returns: Non-zero on success, zero on allocation failure.

See also: gdContextClip

◆ gdContextCreateForImage()

gdContextPtr gdContextCreateForImage ( gdImagePtr image )

Create a 2D drawing context for a truecolor image.

The context keeps an internal premultiplied ARGB surface. Existing image pixels are loaded into the context when it is created. Use gdContextFlushImage or gdContextDestroy to write drawing results back to the image.

Parameters

image A truecolor image.

Returns: gdContextPtr a new drawing context , or NULL if image is NULL, not truecolor, or allocation fails.

See also:

See also
gdContextFlushImage gdContextDestroy gdContextDestroyNoFlush

◆ gdContextDestroy()

void gdContextDestroy ( gdContextPtr context )

Destroy a context and flush drawing changes to the backing image.

Passing NULL has no effect.

Parameters

context The context to destroy.

See also: gdContextDestroyNoFlush

◆ gdContextDestroyNoFlush()

void gdContextDestroyNoFlush ( gdContextPtr context )

Destroy a context without flushing drawing changes to the backing image.

Passing NULL has no effect.

Parameters

context The context to destroy.

See also: gdContextDestroy

◆ gdContextFill()

void gdContextFill ( gdContextPtr context )

Fill the current path and then clear it.

See also: gdContextFillPreserve

◆ gdContextFlushImage()

void gdContextFlushImage ( gdContextPtr context )

Copy the context's drawing surface back into its image.

Parameters

context The drawing context.

See also: gdContextCreateForImage gdContextReloadImage

◆ gdContextGetImage()

gdImagePtr gdContextGetImage ( gdContextPtr context )

Get the image associated with a context.

Parameters

context The drawing context.

Returns: The backing image, or NULL if context is NULL or has no backing image.

◆ gdContextGetPatternFilter()

gdPatternFilter gdContextGetPatternFilter ( gdContextPtr context )

Get the current default image-pattern filter from a context.

Parameters

context The drawing context.

Returns: The current pattern filter. If context is NULL, GD_PATTERN_FILTER_GOOD is returned.

See also: gdContextSetPatternFilter

◆ gdContextReloadImage()

int gdContextReloadImage ( gdContextPtr context )

Reload the context drawing surface from its backing image.

This discards unflushed drawing changes in the context.

Parameters

context The drawing context.

Returns: Non-zero on success, zero on failure.

See also: gdContextFlushImage

◆ gdContextRestore()

int gdContextRestore ( gdContextPtr context )

Restore the most recently saved graphics state.

Parameters

context The drawing context.

Returns: Non-zero on success, zero if there is no saved state or context is NULL.

See also: gdContextSave

◆ gdContextRotate()

void gdContextRotate	(	gdContextPtr	context,
		double	radians
	)

Apply rotation to the current transformation matrix.

Parameters

context	The drawing context.
radians	Rotation angle in radians.

◆ gdContextSave()

int gdContextSave ( gdContextPtr context )

Save the current graphics state.

The saved state includes source, operator, opacity, transform, clip, stroke settings, fill rule, font settings, and pattern filter.

Parameters

context The drawing context.

Returns: Non-zero on success, zero on failure.

See also: gdContextRestore

◆ gdContextSetDash()

void gdContextSetDash	(	gdContextPtr	context,
		double	offset,
		const double *	data,
		int	size
	)

Set the stroke dash pattern.

Parameters

context	The drawing context.
offset	Dash phase offset.
data	Dash segment lengths.
size	Number of dash segment lengths.

◆ gdContextSetFontFace()

void gdContextSetFontFace	(	gdContextPtr	context,
		gdFontFacePtr	face
	)

Set the current font face for text operations.

The context keeps its own reference to the font face. Passing NULL clears the current font face.

Parameters

context	The drawing context.
face	The font face to use, or NULL.

See also: gdFontFaceCreateFromFile gdContextShowText

◆ gdContextSetFontSize()

void gdContextSetFontSize	(	gdContextPtr	context,
		double	size
	)

Set the current font size for text operations.

Parameters

context	The drawing context.
size	Font size in user-space units. Non-positive or non-finite values are ignored.

◆ gdContextSetOpacity()

void gdContextSetOpacity	(	gdContextPtr	context,
		double	opacity
	)

Set a global opacity multiplier for subsequent drawing.

Parameters

context	The drawing context.
opacity	Opacity value. Values are clamped to the range 0.0 to 1.0.

◆ gdContextSetOperator()

void gdContextSetOperator	(	gdContextPtr	context,
		gdCompositeOperator	op
	)

Set the compositing operator used for subsequent drawing.

Parameters

context	The drawing context.
op	The compositing operator.

See also: gdCompositeOperator

◆ gdContextSetPatternFilter()

void gdContextSetPatternFilter	(	gdContextPtr	context,
		gdPatternFilter	filter
	)

Set the default image-pattern filter for patterns created by context source helpers such as gdContextSetSourceImage.

This value is part of the graphics state and is saved and restored by gdContextSave and gdContextRestore. It does not modify patterns that have already been created; use gdPathPatternSetFilter for explicit pattern objects.

Parameters

context	The drawing context.
filter	The requested pattern sampling quality.

See also: gdPatternFilter gdContextGetPatternFilter gdPathPatternSetFilter

◆ gdContextSetSource()

void gdContextSetSource	(	gdContextPtr	context,
		gdPaintPtr	source
	)

Set the current source paint.

The context keeps its own reference to the paint. The caller may destroy its reference after this call.

Parameters

context	The drawing context.
source	The paint to use for subsequent drawing.

◆ gdContextSetSourceImage()

void gdContextSetSourceImage	(	gdContextPtr	context,
		gdImagePtr	image,
		double	x,
		double	y
	)

Set the current source paint to an image pattern.

The image is snapshotted when this function is called, so later changes to the source image do not affect the pattern. The source image is positioned by translating the pattern by (x, y). The pattern inherits the context's current pattern filter; use gdContextSetPatternFilter before this call to choose FAST, GOOD, or BEST sampling for transformed image fills.

Parameters

context	The drawing context.
image	The image to use as the source pattern.
x	The pattern x offset in user space.
y	The pattern y offset in user space.

See also:

◆ gdContextSetSourceRgb()

void gdContextSetSourceRgb	(	gdContextPtr	context,
		double	r,
		double	g,
		double	b
	)

Set the current source paint to an opaque RGB color.

Color components use the range 0.0 to 1.0.

Parameters

context	The drawing context.
r	Red component.
g	Green component.
b	Blue component.

◆ gdContextSetSourceRgba()

void gdContextSetSourceRgba	(	gdContextPtr	context,
		double	r,
		double	g,
		double	b,
		double	a
	)

Set the current source paint to a solid RGBA color.

Color components use the range 0.0 to 1.0.

Parameters

context	The drawing context.
r	Red component.
g	Green component.
b	Blue component.
a	Alpha component.

◆ gdContextShowText()

gdTextStatus gdContextShowText	(	gdContextPtr	context,
		const char *	utf8,
		double	x,
		double	y,
		const gdTextOptions *	options,
		gdTextError *	err
	)

Draw UTF-8 text using the current source paint.

This appends the text path, fills it, and clears the current path as part of gdContextFill.

Parameters

context	The drawing context.
utf8	UTF-8 text.
x	Text origin x coordinate.
y	Text origin y coordinate.
options	Optional text options, or NULL for defaults.
err	Optional error output.

Returns: GD_TEXT_OK on success, or another gdTextStatus value on failure.

◆ gdContextStroke()

void gdContextStroke ( gdContextPtr context )

Stroke the current path and then clear it.

See also: gdContextStrokePreserve

◆ gdContextTextExtents()

gdTextStatus gdContextTextExtents	(	gdContextPtr	context,
		const char *	utf8,
		const gdTextOptions *	options,
		gdTextExtents *	extents,
		gdTextError *	err
	)

Measure UTF-8 text using the current font face and font size.

Parameters

context	The drawing context.
utf8	UTF-8 text.
options	Optional text options, or NULL for defaults.
extents	Where to store text metrics.
err	Optional error output.

Returns: GD_TEXT_OK on success, or another gdTextStatus value on failure.

◆ gdContextTextPath()

gdTextStatus gdContextTextPath	(	gdContextPtr	context,
		const char *	utf8,
		double	x,
		double	y,
		const gdTextOptions *	options,
		gdTextError *	err
	)

Convert UTF-8 text to path contours and append them to the current path.

Text is positioned with its origin at (x, y). The current font face and font size are taken from the context.

Parameters

context	The drawing context.
utf8	UTF-8 text.
x	Text origin x coordinate.
y	Text origin y coordinate.
options	Optional text options, or NULL for defaults.
err	Optional error output.

Returns: GD_TEXT_OK on success, or another gdTextStatus value on failure.

See also: gdContextShowText gdContextTextExtents

◆ gdContextTransform()

void gdContextTransform	(	gdContextPtr	context,
		const gdPathMatrixPtr	matrix
	)

Apply an affine transformation to the current transformation matrix.

Parameters

context	The drawing context.
matrix	The transform to apply.

◆ gdFontFaceAddRef()

gdFontFacePtr gdFontFaceAddRef ( gdFontFacePtr face )

Add a reference to a font face.

Parameters

face	The font face to add a reference to.

Returns: The same font face, or NULL if face is NULL.

◆ gdFontFaceCreateFromData()

gdFontFacePtr gdFontFaceCreateFromData	(	const unsigned char *	data,
		size_t	size,
		int	face_index,
		gdTextError *	err
	)

Load a font face from memory.

The caller must keep the data buffer alive for the lifetime of the font face.

Parameters

data	Font data.
size	Font data size in bytes.
face_index	Face index within the font data.
err	Optional error output.

Returns: A new font face, or NULL on failure.

◆ gdFontFaceCreateFromFile()

gdFontFacePtr gdFontFaceCreateFromFile	(	const char *	path,
		int	face_index,
		gdTextError *	err
	)

Load a font face from a file.

Parameters

path	Font file path.
face_index	Face index within the font file.
err	Optional error output.

Returns: A new font face, or NULL on failure.

◆ gdImageComposite()

int gdImageComposite	(	gdImagePtr	dst,
		const gdImagePtr	src,
		int	dst_x,
		int	dst_y,
		gdCompositeOperator	op,
		double	opacity,
		gdRectPtr	src_region,
		gdRectPtr	clip
	)

Composite a source image into a truecolor destination image.

Parameters

dst	Destination image.
src	Source image.
dst_x	Destination x offset.
dst_y	Destination y offset.
op	Composite operator.
opacity	Global source opacity, from 0.0 to 1.0.
src_region	Optional source rectangle.
clip	Optional destination clip rectangle.

Returns: GD_TRUE on success, or GD_FALSE for invalid arguments.

◆ gdPaintAddColorStopRgb()

int gdPaintAddColorStopRgb	(	gdPaintPtr	paint,
		double	offset,
		double	r,
		double	g,
		double	b
	)

Add an opaque color stop to a gradient paint.

Parameters

paint	- A linear or radial gradient paint.
offset	- Stop offset in the range 0.0 to 1.0.
r	- Red component in the range 0.0 to 1.0.
g	- Green component in the range 0.0 to 1.0.
b	- Blue component in the range 0.0 to 1.0.

Returns: Non-zero on success, zero on invalid input or allocation failure.

See also:

See also
gdPaintAddColorStopRgba

◆ gdPaintAddColorStopRgba()

int gdPaintAddColorStopRgba	(	gdPaintPtr	paint,
		double	offset,
		double	r,
		double	g,
		double	b,
		double	a
	)

Add a color stop with opacity to a gradient paint.

Multiple stops may have the same offset. Stops are kept in insertion order for equal offsets.

Parameters

paint	- A linear or radial gradient paint.
offset	- Stop offset in the range 0.0 to 1.0.
r	- Red component in the range 0.0 to 1.0.
g	- Green component in the range 0.0 to 1.0.
b	- Blue component in the range 0.0 to 1.0.
a	- Alpha component in the range 0.0 to 1.0.

Returns: Non-zero on success, zero on invalid input or allocation failure.

See also: gdPaintAddColorStopRgb

◆ gdPaintCreateFromPattern()

gdPaintPtr gdPaintCreateFromPattern ( gdPathPatternPtr pattern )

Create a paint object from an image pattern.

The paint holds a reference to the pattern. The caller may destroy its own pattern reference after creating the paint.

Parameters

pattern The pattern to use as a paint source.

Returns: A new paint object, or NULL on allocation failure.

See also: gdPathPatternCreateForImage gdPathPatternSetFilter gdContextSetSource

◆ gdPaintCreateLinear()

gdPaintPtr gdPaintCreateLinear	(	double	x0,
		double	y0,
		double	x1,
		double	y1
	)

Create a linear gradient paint.

The gradient parameter runs from (x0, y0) to (x1, y1). Add color stops with gdPaintAddColorStopRgb or gdPaintAddColorStopRgba.

Parameters

x0	Start point x coordinate.
y0	Start point y coordinate.
x1	End point x coordinate.
y1	End point y coordinate.

Returns: A new paint object, or NULL on invalid input or allocation failure.

◆ gdPaintCreateRadial()

gdPaintPtr gdPaintCreateRadial	(	double	x0,
		double	y0,
		double	r0,
		double	x1,
		double	y1,
		double	r1
	)

Create a radial gradient paint between two circles.

Add color stops with gdPaintAddColorStopRgb or gdPaintAddColorStopRgba.

Parameters

x0	First circle center x coordinate.
y0	First circle center y coordinate.
r0	First circle radius. Must be non-negative.
x1	Second circle center x coordinate.
y1	Second circle center y coordinate.
r1	Second circle radius. Must be non-negative.

Returns: A new paint object, or NULL on invalid input or allocation failure.

◆ gdPaintSetExtend()

int gdPaintSetExtend	(	gdPaintPtr	paint,
		gdExtendMode	extend
	)

Set the extend mode for a gradient or pattern paint.

Parameters

paint	- The paint to update.
extend	- The extend mode.

Returns: Non-zero on success, zero if the paint type or extend mode is invalid.

See also:

See also
gdExtendMode

◆ gdPaintSetMatrix()

int gdPaintSetMatrix	(	gdPaintPtr	paint,
		const gdPathMatrixPtr	matrix
	)

Set the paint's pattern or gradient transform.

The matrix must be finite and invertible.

Parameters

paint	- The paint to update.
matrix	- The paint matrix.

Returns: Non-zero on success, zero on invalid input.

◆ gdPathAppendPath()

void gdPathAppendPath	(	gdPathPtr	path,
		const gdPathPtr	source
	)

Append all contours from one path to another.

Parameters

path	- The destination path.
source	- The path to append.

◆ gdPathArc()

void gdPathArc	(	gdPathPtr	path,
		double	cx,
		double	cy,
		double	radius,
		double	angle1,
		double	angle2
	)

Add a circular arc in the positive-angle direction. Angles are in radians. A line is added from the current point to the beginning of the arc when necessary.

Parameters

path	- The path to modify.
cx	- The center's horizontal coordinate.
cy	- The center's vertical coordinate.
radius	- The arc radius.
angle1	- The starting angle in radians.
angle2	- The ending angle in radians.

◆ gdPathArcTo()

void gdPathArcTo	(	gdPathPtr	path,
		double	x1,
		double	y1,
		double	x2,
		double	y2,
		double	radius
	)

Connect the current point to (x1, y1) and (x2, y2) with a circular arc tangent to both line segments. Degenerate geometry or a non-positive radius adds a line to (x1, y1).

Parameters

path	- The path to modify.
x1	- The corner's horizontal coordinate.
y1	- The corner's vertical coordinate.
x2	- The second tangent line's horizontal endpoint.
y2	- The second tangent line's vertical endpoint.
radius	- The arc radius.

◆ gdPathClose()

void gdPathClose ( gdPathPtr path )

Close the current contour with a line to its starting point. An empty path or an already closed contour is unchanged.

Parameters

path	- The path to modify.

◆ gdPathCreate()

gdPathPtr gdPathCreate ( void )

Create an empty path.

Returns: A new path, or NULL if allocation fails. Destroy it with gdPathDestroy.

◆ gdPathCurveTo()

void gdPathCurveTo	(	gdPathPtr	path,
		double	x1,
		double	y1,
		double	x2,
		double	y2,
		double	x3,
		double	y3
	)

Add a cubic Bezier curve.

Parameters

path	- The path to modify.
x1	- The first control point's horizontal coordinate.
y1	- The first control point's vertical coordinate.
x2	- The second control point's horizontal coordinate.
y2	- The second control point's vertical coordinate.
x3	- The endpoint's horizontal coordinate.
y3	- The endpoint's vertical coordinate.

◆ gdPathDestroy()

void gdPathDestroy ( gdPathPtr path )

Release a path. Passing NULL has no effect.

Parameters

path	- The path to release.

◆ gdPathDuplicate()

gdPathPtr gdPathDuplicate ( const gdPathPtr path )

Create an independent copy of a path.

Parameters

path	- The path to copy. Must not be NULL.

Returns: A new path, or NULL if path is NULL or allocation fails. Destroy the copy with gdPathDestroy.

◆ gdPathLineTo()

void gdPathLineTo	(	gdPathPtr	path,
		double	x,
		double	y
	)

Add a straight line to an absolute position.

Parameters

path	- The path to modify.
x	- The endpoint's horizontal coordinate.
y	- The endpoint's vertical coordinate.

◆ gdPathMatrixInit()

void gdPathMatrixInit	(	gdPathMatrixPtr	matrix,
		double	m00,
		double	m10,
		double	m01,
		double	m11,
		double	m02,
		double	m12
	)

Initialize an affine transformation matrix from its six coefficients.

A point is mapped to (x * m00 + y * m01 + m02, x * m10 + y * m11 + m12).

Parameters

matrix	- The matrix to initialize.
m00	- The horizontal x coefficient.
m10	- The vertical x coefficient.
m01	- The horizontal y coefficient.
m11	- The vertical y coefficient.
m02	- The horizontal translation.
m12	- The vertical translation.

See also: gdPathMatrixInitIdentity gdPathMatrixMap

◆ gdPathMatrixInitIdentity()

void gdPathMatrixInitIdentity ( gdPathMatrixPtr matrix )

Initialize a matrix to the identity transformation.

Parameters

matrix - The matrix to initialize.

◆ gdPathMatrixInitRotate()

void gdPathMatrixInitRotate	(	gdPathMatrixPtr	matrix,
		double	radians
	)

Initialize a rotation matrix about the origin.

Parameters

matrix	- The matrix to initialize.
radians	- The rotation angle, in radians.

◆ gdPathMatrixInitRotateTranslate()

void gdPathMatrixInitRotateTranslate	(	gdPathMatrixPtr	matrix,
		double	radians,
		double	x,
		double	y
	)

Initialize a rotation matrix about a specified point. The point (x, y) remains unchanged by the resulting transformation.

Parameters

matrix	- The matrix to initialize.
radians	- The rotation angle, in radians.
x	- The horizontal coordinate of the rotation center.
y	- The vertical coordinate of the rotation center.

◆ gdPathMatrixInitScale()

void gdPathMatrixInitScale	(	gdPathMatrixPtr	matrix,
		double	x,
		double	y
	)

Initialize a scaling matrix.

Parameters

matrix	- The matrix to initialize.
x	- The horizontal scale factor.
y	- The vertical scale factor.

◆ gdPathMatrixInitShear()

void gdPathMatrixInitShear	(	gdPathMatrixPtr	matrix,
		double	x,
		double	y
	)

Initialize a shear matrix. The shear factors are the tangents of the supplied angles.

Parameters

matrix	- The matrix to initialize.
x	- The horizontal shear angle, in radians.
y	- The vertical shear angle, in radians.

◆ gdPathMatrixInitTranslate()

void gdPathMatrixInitTranslate	(	gdPathMatrixPtr	matrix,
		double	x,
		double	y
	)

Initialize a translation matrix.

Parameters

matrix	- The matrix to initialize.
x	- The horizontal translation.
y	- The vertical translation.

◆ gdPathMatrixInvert()

int gdPathMatrixInvert ( gdPathMatrixPtr matrix )

Invert an affine transformation in place. A singular matrix is left unchanged.

Parameters

matrix - The matrix to invert.

Returns: Non-zero on success, or zero if the matrix is singular.

◆ gdPathMatrixMap()

void gdPathMatrixMap	(	const gdPathMatrixPtr	matrix,
		double	x,
		double	y,
		double *	result_x,
		double *	result_y
	)

Transform a pair of coordinates.

Parameters

matrix	- The transformation matrix.
x	- The source horizontal coordinate.
y	- The source vertical coordinate.
result_x	- Where to store the transformed horizontal coordinate.
result_y	- Where to store the transformed vertical coordinate.

◆ gdPathMatrixMapPoint()

void gdPathMatrixMapPoint	(	const gdPathMatrixPtr	matrix,
		const gdPointFPtr	src,
		gdPointFPtr	dst
	)

Transform a point. src and dst may point to the same object.

Parameters

matrix	- The transformation matrix.
src	- The source point.
dst	- Where to store the transformed point.

◆ gdPathMatrixMapRect()

void gdPathMatrixMapRect	(	const gdPathMatrixPtr	matrix,
		const gdRectFPtr	src,
		gdRectFPtr	dst
	)

Transform all four corners of a rectangle and calculate their axis-aligned bounding box. src and dst may point to the same object.

Parameters

matrix	- The transformation matrix.
src	- The source rectangle.
dst	- Where to store the transformed bounding rectangle.

◆ gdPathMatrixMultiply()

void gdPathMatrixMultiply	(	gdPathMatrixPtr	matrix,
		const gdPathMatrixPtr	a,
		const gdPathMatrixPtr	b
	)

Compose two affine transformations. The result maps through a first and then through b. matrix may alias a or b.

Parameters

matrix	- The destination matrix.
a	- The transformation applied first.
b	- The transformation applied second.

◆ gdPathMatrixRotate()

void gdPathMatrixRotate	(	gdPathMatrixPtr	matrix,
		double	radians
	)

Apply a rotation about the origin before the transformation already in a matrix.

Parameters

matrix	- The matrix to modify.
radians	- The rotation angle, in radians.

◆ gdPathMatrixRotateTranslate()

void gdPathMatrixRotateTranslate	(	gdPathMatrixPtr	matrix,
		double	radians,
		double	x,
		double	y
	)

Apply a rotation about a specified point before the transformation already in a matrix.

Parameters

matrix	- The matrix to modify.
radians	- The rotation angle, in radians.
x	- The horizontal coordinate of the rotation center.
y	- The vertical coordinate of the rotation center.

◆ gdPathMatrixScale()

void gdPathMatrixScale	(	gdPathMatrixPtr	matrix,
		double	x,
		double	y
	)

Apply scaling before the transformation already in a matrix.

Parameters

matrix	- The matrix to modify.
x	- The horizontal scale factor.
y	- The vertical scale factor.

◆ gdPathMatrixShear()

void gdPathMatrixShear	(	gdPathMatrixPtr	matrix,
		double	x,
		double	y
	)

Apply a shear before the transformation already in a matrix.

Parameters

matrix	- The matrix to modify.
x	- The horizontal shear angle, in radians.
y	- The vertical shear angle, in radians.

◆ gdPathMatrixTranslate()

void gdPathMatrixTranslate	(	gdPathMatrixPtr	matrix,
		double	x,
		double	y
	)

Apply a translation before the transformation already in a matrix.

Parameters

matrix	- The matrix to modify.
x	- The horizontal translation.
y	- The vertical translation.

◆ gdPathMoveTo()

void gdPathMoveTo	(	gdPathPtr	path,
		double	x,
		double	y
	)

Start a new contour at an absolute position.

Parameters

path	- The path to modify.
x	- The horizontal coordinate.
y	- The vertical coordinate.

◆ gdPathNegativeArc()

void gdPathNegativeArc	(	gdPathPtr	path,
		double	cx,
		double	cy,
		double	radius,
		double	angle1,
		double	angle2
	)

Add a circular arc in the negative-angle direction. Angles are in radians. A line is added from the current point to the beginning of the arc when necessary.

Parameters

path	- The path to modify.
cx	- The center's horizontal coordinate.
cy	- The center's vertical coordinate.
radius	- The arc radius.
angle1	- The starting angle in radians.
angle2	- The ending angle in radians.

◆ gdPathPatternCreateForImage()

gdPathPatternPtr gdPathPatternCreateForImage ( gdImagePtr image )

Create an image pattern from a gd image.

The image contents are copied into an internal surface when the pattern is created. The new pattern uses GD_EXTEND_NONE, identity matrix, full opacity, and GD_PATTERN_FILTER_GOOD by default.

Parameters

image - The image to snapshot into a pattern.

Returns: A new pattern, or NULL on failure.

See also:

See also
gdPathPatternDestroy gdPathPatternSetFilter gdPaintCreateFromPattern

◆ gdPathPatternGetFilter()

gdPatternFilter gdPathPatternGetFilter ( gdPathPatternPtr pattern )

Get the sampling quality for an image pattern.

Parameters

pattern - The pattern to query.

Returns: The pattern filter. If pattern is NULL, GD_PATTERN_FILTER_GOOD is returned.

See also: gdPathPatternSetFilter

◆ gdPathPatternSetExtend()

void gdPathPatternSetExtend	(	gdPathPatternPtr	pattern,
		gdExtendMode	extend
	)

Set how an image pattern is sampled outside its image bounds.

Parameters

pattern	- The pattern to update.
extend	- The extend mode.

See also: gdExtendMode

◆ gdPathPatternSetFilter()

void gdPathPatternSetFilter	(	gdPathPatternPtr	pattern,
		gdPatternFilter	filter
	)

Set the sampling quality for an image pattern.

The filter is used when the pattern image is transformed during painting. FAST requests nearest-neighbour sampling, GOOD requests balanced quality, and BEST requests the highest practical software quality. The exact kernel used for GOOD or BEST is intentionally an implementation detail.

Parameters

pattern	- The pattern to update.
filter	- The requested pattern sampling quality.

See also: gdPatternFilter gdPathPatternGetFilter gdContextSetPatternFilter

◆ gdPathPatternSetMatrix()

void gdPathPatternSetMatrix	(	gdPathPatternPtr	pattern,
		gdPathMatrixPtr	matrix
	)

Set the pattern-to-user-space transform for an image pattern.

The matrix controls how the pattern image is positioned, scaled, rotated, or sheared before it is used as a fill source.

Parameters

pattern	- The pattern to update.
matrix	- The pattern matrix.

See also: gdPathMatrix gdContextSetSourceImage

◆ gdPathPatternSetOpacity()

void gdPathPatternSetOpacity	(	gdPathPatternPtr	pattern,
		double	opacity
	)

Set the opacity multiplier for an image pattern.

Parameters

pattern	- The pattern to update.
opacity	- The opacity value. Values are clamped to the range 0.0 to 1.0.

◆ gdPathQuadTo()

void gdPathQuadTo	(	gdPathPtr	path,
		double	x1,
		double	y1,
		double	x2,
		double	y2
	)

Add a quadratic Bezier curve.

Parameters

path	- The path to modify.
x1	- The control point's horizontal coordinate.
y1	- The control point's vertical coordinate.
x2	- The endpoint's horizontal coordinate.
y2	- The endpoint's vertical coordinate.

◆ gdPathRectangle()

void gdPathRectangle	(	gdPathPtr	path,
		double	x,
		double	y,
		double	width,
		double	height
	)

Add a closed rectangular contour.

Parameters

path	- The path to modify.
x	- The rectangle's left coordinate.
y	- The rectangle's top coordinate.
width	- The rectangle width.
height	- The rectangle height.

◆ gdPathRelCurveTo()

void gdPathRelCurveTo	(	gdPathPtr	path,
		double	dx1,
		double	dy1,
		double	dx2,
		double	dy2,
		double	dx3,
		double	dy3
	)

Add a cubic Bezier curve using offsets from the current point.

Parameters

path	- The path to modify.
dx1	- The first control point's horizontal offset.
dy1	- The first control point's vertical offset.
dx2	- The second control point's horizontal offset.
dy2	- The second control point's vertical offset.
dx3	- The endpoint's horizontal offset.
dy3	- The endpoint's vertical offset.

◆ gdPathRelLineTo()

void gdPathRelLineTo	(	gdPathPtr	path,
		double	dx,
		double	dy
	)

Add a straight line using an offset from the current point.

Parameters

path	- The path to modify.
dx	- The horizontal offset.
dy	- The vertical offset.

◆ gdPathRelMoveTo()

void gdPathRelMoveTo	(	gdPathPtr	path,
		double	dx,
		double	dy
	)

Start a new contour at an offset from the current point. For an empty path, the offset is relative to (0, 0).

Parameters

path	- The path to modify.
dx	- The horizontal offset.
dy	- The vertical offset.

◆ gdPathRelQuadTo()

void gdPathRelQuadTo	(	gdPathPtr	path,
		double	dx1,
		double	dy1,
		double	dx2,
		double	dy2
	)

Add a quadratic Bezier curve using offsets from the current point.

Parameters

path	- The path to modify.
dx1	- The control point's horizontal offset.
dy1	- The control point's vertical offset.
dx2	- The endpoint's horizontal offset.
dy2	- The endpoint's vertical offset.

◆ gdPathTransform()

void gdPathTransform	(	gdPathPtr	path,
		const gdPathMatrixPtr	matrix
	)

Transform every point in a path in place.

Parameters

path	- The path to transform.
matrix	- The transformation matrix.

◆ gdTextOptionsInit()

void gdTextOptionsInit ( gdTextOptions * options )

Initialize text options to defaults.

Defaults are basic shaping, line spacing of 1.0, and zeroed reserved fields.

Parameters

options The options structure to initialize.

Data Structures

Typedefs

Enumerations

Functions

Detailed Description

Typedef Documentation

◆ gdContext

◆ gdContextPtr

◆ gdFontFace

◆ gdFontFacePtr

◆ gdPaint

◆ gdPaintPtr

◆ gdPath

◆ gdPathMatrix

◆ gdPathPattern

◆ gdPathPatternPtr

◆ gdPathPtr

◆ gdRectF

◆ gdRectFPtr

Enumeration Type Documentation

◆ gdCompositeOperator

◆ gdExtendMode

◆ gdFillRule

◆ gdLineCap

◆ gdLineJoin

◆ gdPatternFilter

◆ gdTextShaping

◆ gdTextStatus

Function Documentation

◆ gdContextAppendPath()

◆ gdContextClip()

◆ gdContextClipPreserve()

◆ gdContextCreateForImage()

◆ gdContextDestroy()

◆ gdContextDestroyNoFlush()

◆ gdContextFill()

◆ gdContextFlushImage()

◆ gdContextGetImage()

◆ gdContextGetPatternFilter()

◆ gdContextReloadImage()

◆ gdContextRestore()

◆ gdContextRotate()

◆ gdContextSave()

◆ gdContextSetDash()

◆ gdContextSetFontFace()

◆ gdContextSetFontSize()

◆ gdContextSetOpacity()

◆ gdContextSetOperator()

◆ gdContextSetPatternFilter()

◆ gdContextSetSource()

◆ gdContextSetSourceImage()

◆ gdContextSetSourceRgb()

◆ gdContextSetSourceRgba()

◆ gdContextShowText()

◆ gdContextStroke()

◆ gdContextTextExtents()

◆ gdContextTextPath()

◆ gdContextTransform()

◆ gdFontFaceAddRef()

◆ gdFontFaceCreateFromData()

◆ gdFontFaceCreateFromFile()

◆ gdImageComposite()

◆ gdPaintAddColorStopRgb()

◆ gdPaintAddColorStopRgba()

◆ gdPaintCreateFromPattern()

◆ gdPaintCreateLinear()

◆ gdPaintCreateRadial()

◆ gdPaintSetExtend()

◆ gdPaintSetMatrix()

◆ gdPathAppendPath()

◆ gdPathArc()

◆ gdPathArcTo()

◆ gdPathClose()

◆ gdPathCreate()

◆ gdPathCurveTo()

◆ gdPathDestroy()

◆ gdPathDuplicate()

◆ gdPathLineTo()

◆ gdPathMatrixInit()

◆ gdPathMatrixInitIdentity()