draw
User-friendly methods to draw on an image
Contents
DrawAnnotation
Synopsis
void DrawAnnotation( DrawContext context, const double x, const double y, const unsigned char *text );
Description
DrawAnnotation() draws text on the image.
The format of the DrawAnnotation method is:
void DrawAnnotation( DrawContext context, const double x, const double y, const unsigned char *text );
- context:
drawing context
- x:
x ordinate to left of text
- y:
y ordinate to text baseline
- text:
text to draw
DrawAffine
Synopsis
void DrawAffine( DrawContext context, const AffineMatrix *affine );
Description
DrawAffine() adjusts the current affine transformation matrix with the specified affine transformation matrix. Note that the current affine transform is adjusted rather than replaced.
The format of the DrawAffine method is:
void DrawAffine( DrawContext context, const AffineMatrix *affine );
A description of each parameter follows:
- context:
Drawing context
- affine:
Affine matrix parameters
DrawAllocateContext
Synopsis
DrawContext DrawAllocateContext( const DrawInfo *draw_info, Image *image );
Description
DrawAllocateContext() allocates an initial drawing context which is an opaque handle required by the remaining drawing methods.
The format of the DrawAllocateContext method is:
DrawContext DrawAllocateContext( const DrawInfo *draw_info, Image *image );
- draw_info:
Initial drawing defaults. Set to NULL to use GraphicsMagick defaults.
- image:
The image to draw on.
DrawArc
Synopsis
void DrawArc( DrawContext context, const double sx, const double sy, const double ex, const double ey, const double sd, const double ed );
Description
DrawArc() draws an arc falling within a specified bounding rectangle on the image.
The format of the DrawArc method is:
void DrawArc( DrawContext context, const double sx, const double sy, const double ex, const double ey, const double sd, const double ed );
- context:
drawing context
- sx:
starting x ordinate of bounding rectangle
- sy:
starting y ordinate of bounding rectangle
- ex:
ending x ordinate of bounding rectangle
- ey:
ending y ordinate of bounding rectangle
- sd:
starting degrees of rotation
- ed:
ending degrees of rotation
DrawBezier
Synopsis
void DrawBezier( DrawContext context, const unsigned long num_coords, const PointInfo *coordinates );
Description
DrawBezier() draws a bezier curve through a set of points on the image.
The format of the DrawBezier method is:
void DrawBezier( DrawContext context, const unsigned long num_coords, const PointInfo *coordinates );
- context:
drawing context
- num_coords:
number of coordinates
- coordinates:
coordinates
DrawCircle
Synopsis
void DrawCircle( DrawContext context, const double ox, const double oy, const double px, const double py );
Description
DrawCircle() draws a circle on the image.
The format of the DrawCircle method is:
void DrawCircle( DrawContext context, const double ox, const double oy, const double px, const double py );
- context:
drawing context
- ox:
origin x ordinate
- oy:
origin y ordinate
- px:
perimeter x ordinate
- py:
perimeter y ordinate
DrawGetClipPath
Synopsis
char *DrawGetClipPath( DrawContext context );
Description
DrawGetClipPath() obtains the current clipping path ID. The value returned must be deallocated by the user when it is no longer needed.
The format of the DrawGetClipPath method is:
char *DrawGetClipPath( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetClipPath
Synopsis
void DrawSetClipPath( DrawContext context, const char *clip_path );
Description
DrawSetClipPath() associates a named clipping path with the image. Only the areas drawn on by the clipping path will be modified as long as it remains in effect.
The format of the DrawSetClipPath method is:
void DrawSetClipPath( DrawContext context, const char *clip_path );
A description of each parameter follows:
- context:
drawing context
- clip_path:
name of clipping path to associate with image
DrawGetClipRule
Synopsis
FillRule DrawGetClipRule( DrawContext context );
Description
DrawGetClipRule() returns the current polygon fill rule to be used by the clipping path.
The format of the DrawGetClipRule method is:
FillRule DrawGetClipRule( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetClipRule
Synopsis
void DrawSetClipRule( DrawContext context, const FillRule fill_rule );
Description
DrawSetClipRule() set the polygon fill rule to be used by the clipping path.
The format of the DrawSetClipRule method is:
void DrawSetClipRule( DrawContext context, const FillRule fill_rule );
- context:
drawing context
- fill_rule:
fill rule (EvenOddRule or NonZeroRule)
DrawGetClipUnits
Synopsis
ClipPathUnits DrawGetClipUnits( DrawContext context );
Description
DrawGetClipUnits() returns the interpretation of clip path units.
The format of the DrawGetClipUnits method is:
ClipPathUnits DrawGetClipUnits( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetClipUnits
Synopsis
void DrawSetClipUnits( DrawContext context, const ClipPathUnits clip_units );
Description
DrawSetClipUnits() sets the interpretation of clip path units.
The format of the DrawSetClipUnits method is:
void DrawSetClipUnits( DrawContext context, const ClipPathUnits clip_units );
- context:
drawing context
- clip_units:
units to use (UserSpace, UserSpaceOnUse, or ObjectBoundingBox)
DrawColor
Synopsis
void DrawColor( DrawContext context, const double x, const double y, const PaintMethod paintMethod );
Description
DrawColor() draws color on image using the current fill color, starting at specified position, and using specified paint method. The available paint methods are:
PointMethod: Recolors the target pixel ReplaceMethod: Recolor any pixel that matches the target pixel. FloodfillMethod: Recolors target pixels and matching neighbors. FillToBorderMethod: Recolor target pixels and neighbors not matching border color. ResetMethod: Recolor all pixels.
The format of the DrawColor method is:
void DrawColor( DrawContext context, const double x, const double y, const PaintMethod paintMethod );
- context:
drawing context
- x:
x ordinate
- y:
y ordinate
- paintMethod:
paint method
DrawComment
Synopsis
void DrawComment( DrawContext context, const char *comment );
Description
DrawComment() adds a comment to a vector output stream.
The format of the DrawComment method is:
void DrawComment( DrawContext context, const char *comment );
A description of each parameter follows:
- context:
drawing context
- comment:
comment text
DrawDestroyContext
Synopsis
void DrawDestroyContext( DrawContext context );
Description
DrawDestroyContext() frees all resources associated with the drawing context. Once the drawing context has been freed, it should not be used any further unless it re-allocated.
The format of the DrawDestroyContext method is:
void DrawDestroyContext( DrawContext context );
A description of each parameter follows:
- context:
drawing context to destroy
DrawEllipse
Synopsis
void DrawEllipse( DrawContext context, const double ox, const double oy, const double rx, const double ry, const double start, const double end );
Description
DrawEllipse() draws an ellipse on the image.
The format of the DrawEllipse method is:
void DrawEllipse( DrawContext context, const double ox, const double oy, const double rx, const double ry, const double start, const double end );
- context:
drawing context
- ox:
origin x ordinate
- oy:
origin y ordinate
- rx:
radius in x
- ry:
radius in y
- start:
starting rotation in degrees
- end:
ending rotation in degrees
DrawGetFillColor
Synopsis
PixelPacket DrawGetFillColor( DrawContext context );
Description
DrawGetFillColor() returns the fill color used for drawing filled objects.
The format of the DrawGetFillColor method is:
PixelPacket DrawGetFillColor( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetFillColor
Synopsis
void DrawSetFillColor( DrawContext context, const PixelPacket *fill_color );
Description
DrawSetFillColor() sets the fill color to be used for drawing filled objects.
The format of the DrawSetFillColor method is:
void DrawSetFillColor( DrawContext context, const PixelPacket *fill_color );
- context:
drawing context
- fill_color:
fill color
DrawSetFillColorString
Synopsis
void DrawSetFillColorString( DrawContext context, const char *fill_color );
Description
DrawSetFillColorString() sets the fill color to be used for drawing filled objects.
The format of the DrawSetFillColorString method is:
void DrawSetFillColorString( DrawContext context, const char *fill_color );
A description of each parameter follows:
- context:
drawing context
- fill_color:
fill color
DrawSetFillPatternURL
Synopsis
void DrawSetFillPatternURL( DrawContext context, const char *fill_url );
Description
DrawSetFillPatternURL() sets the URL to use as a fill pattern for filling objects. Only local URLs ("#identifier") are supported at this time. These local URLs are normally created by defining a named fill pattern with DrawPushPattern/DrawPopPattern.
The format of the DrawSetFillPatternURL method is:
void DrawSetFillPatternURL( DrawContext context, const char *fill_url );
A description of each parameter follows:
- context:
drawing context
- fill_url:
URL to use to obtain fill pattern.
DrawGetFillOpacity
Synopsis
double DrawGetFillOpacity( DrawContext context );
Description
DrawGetFillOpacity() returns the opacity used when drawing using the fill color or fill texture. Fully opaque is 1.0.
The format of the DrawGetFillOpacity method is:
double DrawGetFillOpacity( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetFillOpacity
Synopsis
void DrawSetFillOpacity( DrawContext context, const double fill_opacity );
Description
DrawSetFillOpacity() sets the opacity to use when drawing using the fill color or fill texture. Fully opaque is 1.0.
The format of the DrawSetFillOpacity method is:
void DrawSetFillOpacity( DrawContext context, const double fill_opacity );
A description of each parameter follows:
- context:
drawing context
- fill_opacity:
fill opacity
DrawGetFillRule
Synopsis
FillRule DrawGetFillRule( DrawContext context );
Description
DrawGetFillRule() returns the fill rule used while drawing polygons.
The format of the DrawGetFillRule method is:
FillRule DrawGetFillRule( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetFillRule
Synopsis
void DrawSetFillRule( DrawContext context, const FillRule fill_rule );
Description
DrawSetFillRule() sets the fill rule to use while drawing polygons.
The format of the DrawSetFillRule method is:
void DrawSetFillRule( DrawContext context, const FillRule fill_rule );
A description of each parameter follows:
- context:
drawing context
- fill_rule:
fill rule (EvenOddRule or NonZeroRule)
DrawGetFont
Synopsis
char *DrawGetFont( DrawContext context );
Description
DrawGetFont() returns a null-terminaged string specifying the font used when annotating with text. The value returned must be freed by the user when no longer needed.
The format of the DrawGetFont method is:
char *DrawGetFont( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetFont
Synopsis
void DrawSetFont( DrawContext context, const char *font_name );
Description
DrawSetFont() sets the fully-sepecified font to use when annotating with text.
The format of the DrawSetFont method is:
void DrawSetFont( DrawContext context, const char *font_name );
A description of each parameter follows:
- context:
drawing context
- font_name:
font name
DrawGetFontFamily
Synopsis
char *DrawGetFontFamily( DrawContext context );
Description
DrawGetFontFamily() returns the font family to use when annotating with text. The value returned must be freed by the user when it is no longer needed.
The format of the DrawGetFontFamily method is:
char *DrawGetFontFamily( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetFontFamily
Synopsis
void DrawSetFontFamily( DrawContext context, const char *font_family );
Description
DrawSetFontFamily() sets the font family to use when annotating with text.
The format of the DrawSetFontFamily method is:
void DrawSetFontFamily( DrawContext context, const char *font_family );
A description of each parameter follows:
- context:
drawing context
- font_family:
font family
DrawGetFontSize
Synopsis
double DrawGetFontSize( DrawContext context );
Description
DrawGetFontSize() returns the font pointsize used when annotating with text.
The format of the DrawGetFontSize method is:
double DrawGetFontSize( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetFontSize
Synopsis
void DrawSetFontSize( DrawContext context, const double pointsize );
Description
DrawSetFontSize() sets the font pointsize to use when annotating with text.
The format of the DrawSetFontSize method is:
void DrawSetFontSize( DrawContext context, const double pointsize );
A description of each parameter follows:
- context:
drawing context
- pointsize:
text pointsize
DrawGetFontStretch
Synopsis
StretchType DrawGetFontStretch( DrawContext context );
Description
DrawGetFontStretch() returns the font stretch used when annotating with text.
The format of the DrawGetFontStretch method is:
StretchType DrawGetFontStretch( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetFontStretch
Synopsis
void DrawSetFontStretch( DrawContext context, const StretchType font_stretch );
Description
DrawSetFontStretch() sets the font stretch to use when annotating with text. The AnyStretch enumeration acts as a wild-card "don't care" option.
The format of the DrawSetFontStretch method is:
void DrawSetFontStretch( DrawContext context, const StretchType font_stretch );
- context:
drawing context
- font_stretch:
font stretch (NormalStretch, UltraCondensedStretch, CondensedStretch, SemiCondensedStretch, SemiExpandedStretch, ExpandedStretch, ExtraExpandedStretch, UltraExpandedStretch, AnyStretch)
DrawGetFontStyle
Synopsis
StyleType DrawGetFontStyle( DrawContext context );
Description
DrawGetFontStyle() returns the font style used when annotating with text.
The format of the DrawGetFontStyle method is:
StyleType DrawGetFontStyle( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetFontStyle
Synopsis
void DrawSetFontStyle( DrawContext context, const StyleType style );
Description
DrawSetFontStyle() sets the font style to use when annotating with text. The AnyStyle enumeration acts as a wild-card "don't care" option.
The format of the DrawSetFontStyle method is:
void DrawSetFontStyle( DrawContext context, const StyleType style );
A description of each parameter follows:
- context:
drawing context
- style:
font style (NormalStyle, ItalicStyle, ObliqueStyle, AnyStyle)
DrawGetFontWeight
Synopsis
unsigned long DrawGetFontWeight( DrawContext context );
Description
DrawGetFontWeight() returns the font weight used when annotating with text.
The format of the DrawGetFontWeight method is:
unsigned long DrawGetFontWeight( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetFontWeight
Synopsis
void DrawSetFontWeight( DrawContext context, const unsigned long font_weight );
Description
DrawSetFontWeight() sets the font weight to use when annotating with text.
The format of the DrawSetFontWeight method is:
void DrawSetFontWeight( DrawContext context, const unsigned long font_weight );
- context:
drawing context
- font_weight:
font weight (valid range 100-900)
DrawGetGravity
Synopsis
GravityType DrawGetGravity( DrawContext context );
Description
DrawGetGravity() returns the text placement gravity used when annotating with text.
The format of the DrawGetGravity method is:
GravityType DrawGetGravity( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetGravity
Synopsis
void DrawSetGravity( DrawContext context, const GravityType gravity );
Description
DrawSetGravity() sets the text placement gravity to use when annotating with text.
The format of the DrawSetGravity method is:
void DrawSetGravity( DrawContext context, const GravityType gravity );
A description of each parameter follows:
- context:
drawing context
- gravity:
positioning gravity (NorthWestGravity, NorthGravity, NorthEastGravity, WestGravity, CenterGravity, EastGravity, SouthWestGravity, SouthGravity, SouthEastGravity)
DrawComposite
Synopsis
void DrawComposite( DrawContext context, const CompositeOperator composite_operator, const double x, const double y, const double width, const double height, const Image *image );
Description
DrawComposite() composites an image onto the current image, using the specified composition operator, specified position, and at the specified size.
The format of the DrawComposite method is:
void DrawComposite( DrawContext context, const CompositeOperator composite_operator, const double x, const double y, const double width, const double height, const Image *image );
- context:
drawing context
- composite_operator:
composition operator
- x:
x ordinate of top left corner
- y:
y ordinate of top left corner
- width:
Width to resize image to prior to compositing. Specify zero to use existing width.
- height:
Height to resize image to prior to compositing. Specify zero to use existing height.
- image:
Image to composite
DrawLine
Synopsis
void DrawLine( DrawContext context, const double sx, const double sy, const double ex, const double ey );
Description
DrawLine() draws a line on the image using the current stroke color, stroke opacity, and stroke width.
The format of the DrawLine method is:
void DrawLine( DrawContext context, const double sx, const double sy, const double ex, const double ey );
- context:
drawing context
- sx:
starting x ordinate
- sy:
starting y ordinate
- ex:
ending x ordinate
- ey:
ending y ordinate
DrawMatte
Synopsis
void DrawMatte( DrawContext context, const double x, const double y, const PaintMethod paint_method );
Description
DrawMatte() paints on the image's opacity channel in order to set effected pixels to transparent. The available paint methods are:
PointMethod: Select the target pixel ReplaceMethod: Select any pixel that matches the target pixel. FloodfillMethod: Select the target pixel and matching neighbors. FillToBorderMethod: Select the target pixel and neighbors not matching border color. ResetMethod: Select all pixels.
The format of the DrawMatte method is:
void DrawMatte( DrawContext context, const double x, const double y, const PaintMethod paint_method );
- context:
drawing context
- x:
x ordinate
- y:
y ordinate
o paint_method:
DrawPathClose
Synopsis
void DrawPathClose( DrawContext context );
Description
DrawPathClose() adds a path element to the current path which closes the current subpath by drawing a straight line from the current point to the current subpath's most recent starting point (usually, the most recent moveto point).
The format of the DrawPathClose method is:
void DrawPathClose( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawPathCurveToAbsolute
Synopsis
void DrawPathCurveToAbsolute( DrawContext context, const double x1, const double y1, const double x2, const double y2, const double x, const double y );
Description
DrawPathCurveToAbsolute() draws a cubic Bezier curve from the current point to (x,y) using (x1,y1) as the control point at the beginning of the curve and (x2,y2) as the control point at the end of the curve using absolute coordinates. At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybezier.
The format of the DrawPathCurveToAbsolute method is:
void DrawPathCurveToAbsolute( DrawContext context, const double x1, const double y1, const double x2, const double y2, const double x, const double y );
- context:
drawing context
- x1:
x ordinate of control point for curve beginning
- y1:
y ordinate of control point for curve beginning
- x2:
x ordinate of control point for curve ending
- y2:
y ordinate of control point for curve ending
- x:
x ordinate of the end of the curve
- y:
y ordinate of the end of the curve
DrawPathCurveToRelative
Synopsis
void DrawPathCurveToRelative( DrawContext context, const double x1, const double y1, const double x2, const double y2, const double x, const double y );
Description
DrawPathCurveToRelative() draws a cubic Bezier curve from the current point to (x,y) using (x1,y1) as the control point at the beginning of the curve and (x2,y2) as the control point at the end of the curve using relative coordinates. At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybezier.
The format of the DrawPathCurveToRelative method is:
void DrawPathCurveToRelative( DrawContext context, const double x1, const double y1, const double x2, const double y2, const double x, const double y );
- context:
drawing context
- x1:
x ordinate of control point for curve beginning
- y1:
y ordinate of control point for curve beginning
- x2:
x ordinate of control point for curve ending
- y2:
y ordinate of control point for curve ending
- x:
x ordinate of the end of the curve
- y:
y ordinate of the end of the curve
DrawPathCurveToQuadraticBezierAbsolute
Synopsis
void DrawPathCurveToQuadraticBezierAbsolute( DrawContext context, const double x1, const double y1, const double x, const double y );
Description
DrawPathCurveToQuadraticBezierAbsolute() draws a quadratic Bezier curve from the current point to (x,y) using (x1,y1) as the control point using absolute coordinates. At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybezier.
The format of the DrawPathCurveToQuadraticBezierAbsolute method is:
void DrawPathCurveToQuadraticBezierAbsolute( DrawContext context, const double x1, const double y1, const double x, const double y );
- context:
drawing context
- x1:
x ordinate of the control point
- y1:
y ordinate of the control point
- x:
x ordinate of final point
- y:
y ordinate of final point
DrawPathCurveToQuadraticBezierRelative
Synopsis
void DrawPathCurveToQuadraticBezierRelative( DrawContext context, const double x1, const double y1, const double x, const double y );
Description
DrawPathCurveToQuadraticBezierRelative() draws a quadratic Bezier curve from the current point to (x,y) using (x1,y1) as the control point using relative coordinates. At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybezier.
The format of the DrawPathCurveToQuadraticBezierRelative method is:
void DrawPathCurveToQuadraticBezierRelative( DrawContext context, const double x1, const double y1, const double x, const double y );
- context:
drawing context
- x1:
x ordinate of the control point
- y1:
y ordinate of the control point
- x:
x ordinate of final point
- y:
y ordinate of final point
DrawPathCurveToQuadraticBezierSmoothAbsolute
Synopsis
void DrawPathCurveToQuadraticBezierSmoothAbsolute( DrawContext context, const double x, const double y );
Description
DrawPathCurveToQuadraticBezierSmoothAbsolute() draws a quadratic Bezier curve (using absolute coordinates) from the current point to (x,y). The control point is assumed to be the reflection of the control point on the previous command relative to the current point. (If there is no previous command or if the previous command was not a DrawPathCurveToQuadraticBezierAbsolute, DrawPathCurveToQuadraticBezierRelative, DrawPathCurveToQuadraticBezierSmoothAbsolut or DrawPathCurveToQuadraticBezierSmoothRelative, assume the control point is coincident with the current point.). At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybezier.
The format of the DrawPathCurveToQuadraticBezierSmoothAbsolute method is:
void DrawPathCurveToQuadraticBezierSmoothAbsolute( DrawContext context, const double x, const double y );
- context:
drawing context
- x:
x ordinate of final point
- y:
y ordinate of final point
DrawPathCurveToQuadraticBezierSmoothRelative
Synopsis
void DrawPathCurveToQuadraticBezierSmoothRelative( DrawContext context, const double x, const double y );
Description
DrawPathCurveToQuadraticBezierSmoothAbsolute() draws a quadratic Bezier curve (using relative coordinates) from the current point to (x,y). The control point is assumed to be the reflection of the control point on the previous command relative to the current point. (If there is no previous command or if the previous command was not a DrawPathCurveToQuadraticBezierAbsolute, DrawPathCurveToQuadraticBezierRelative, DrawPathCurveToQuadraticBezierSmoothAbsolut or DrawPathCurveToQuadraticBezierSmoothRelative, assume the control point is coincident with the current point.). At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybezier.
The format of the DrawPathCurveToQuadraticBezierSmoothRelative method is:
void DrawPathCurveToQuadraticBezierSmoothRelative( DrawContext context, const double x, const double y );
- context:
drawing context
- x:
x ordinate of final point
- y:
y ordinate of final point
DrawPathCurveToSmoothAbsolute
Synopsis
void DrawPathCurveToSmoothAbsolute( DrawContext context, const double x2, const double y2, const double x, const double y );
Description
DrawPathCurveToSmoothAbsolute() draws a cubic Bezier curve from the current point to (x,y) using absolute coordinates. The first control point is assumed to be the reflection of the second control point on the previous command relative to the current point. (If there is no previous command or if the previous command was not an DrawPathCurveToAbsolute, DrawPathCurveToRelative, DrawPathCurveToSmoothAbsolute or DrawPathCurveToSmoothRelative, assume the first control point is coincident with the current point.) (x2,y2) is the second control point (i.e., the control point at the end of the curve). At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybezier.
The format of the DrawPathCurveToSmoothAbsolute method is:
void DrawPathCurveToSmoothAbsolute( DrawContext context, const double x2, const double y2, const double x, const double y );
- context:
drawing context
- x2:
x ordinate of second control point
- y2:
y ordinate of second control point
- x:
x ordinate of termination point
- y:
y ordinate of termination point
DrawPathCurveToSmoothRelative
Synopsis
void DrawPathCurveToSmoothRelative( DrawContext context, const double x2, const double y2, const double x, const double y );
Description
DrawPathCurveToSmoothRelative() draws a cubic Bezier curve from the current point to (x,y) using relative coordinates. The first control point is assumed to be the reflection of the second control point on the previous command relative to the current point. (If there is no previous command or if the previous command was not an DrawPathCurveToAbsolute, DrawPathCurveToRelative, DrawPathCurveToSmoothAbsolute or DrawPathCurveToSmoothRelative, assume the first control point is coincident with the current point.) (x2,y2) is the second control point (i.e., the control point at the end of the curve). At the end of the command, the new current point becomes the final (x,y) coordinate pair used in the polybezier.
The format of the DrawPathCurveToSmoothRelative method is:
void DrawPathCurveToSmoothRelative( DrawContext context, const double x2, const double y2, const double x, const double y );
- context:
drawing context
- x2:
x ordinate of second control point
- y2:
y ordinate of second control point
- x:
x ordinate of termination point
- y:
y ordinate of termination point
DrawPathEllipticArcAbsolute
Synopsis
void DrawPathEllipticArcAbsolute( DrawContext context, const double rx, const double ry, const double x_axis_rotation, unsigned int large_arc_flag, unsigned int sweep_flag, const double x, const double y );
Description
DrawPathEllipticArcAbsolute() draws an elliptical arc from the current point to (x, y) using absolute coordinates. The size and orientation of the ellipse are defined by two radii (rx, ry) and an xAxisRotation, which indicates how the ellipse as a whole is rotated relative to the current coordinate system. The center (cx, cy) of the ellipse is calculated automatically to satisfy the constraints imposed by the other parameters. largeArcFlag and sweepFlag contribute to the automatic calculations and help determine how the arc is drawn. If largeArcFlag is true then draw the larger of the available arcs. If sweepFlag is true, then draw the arc matching a clock-wise rotation.
The format of the DrawPathEllipticArcAbsolute method is:
void DrawPathEllipticArcAbsolute( DrawContext context, const double rx, const double ry, const double x_axis_rotation, unsigned int large_arc_flag, unsigned int sweep_flag, const double x, const double y );
- context:
drawing context
- rx:
x radius
- ry:
y radius
- x_axis_rotation:
indicates how the ellipse as a whole is rotated relative to the current coordinate system
- large_arc_flag:
If non-zero (true) then draw the larger of the available arcs
- sweep_flag:
If non-zero (true) then draw the arc matching a clock-wise rotation
DrawPathEllipticArcRelative
Synopsis
void DrawPathEllipticArcRelative( DrawContext context, const double rx, const double ry, const double x_axis_rotation, unsigned int large_arc_flag, unsigned int sweep_flag, const double x, const double y );
Description
DrawPathEllipticArcRelative() draws an elliptical arc from the current point to (x, y) using relative coordinates. The size and orientation of the ellipse are defined by two radii (rx, ry) and an xAxisRotation, which indicates how the ellipse as a whole is rotated relative to the current coordinate system. The center (cx, cy) of the ellipse is calculated automatically to satisfy the constraints imposed by the other parameters. largeArcFlag and sweepFlag contribute to the automatic calculations and help determine how the arc is drawn. If largeArcFlag is true then draw the larger of the available arcs. If sweepFlag is true, then draw the arc matching a clock-wise rotation.
The format of the DrawPathEllipticArcRelative method is:
void DrawPathEllipticArcRelative( DrawContext context, const double rx, const double ry, const double x_axis_rotation, unsigned int large_arc_flag, unsigned int sweep_flag, const double x, const double y );
- context:
drawing context
- rx:
x radius
- ry:
y radius
- x_axis_rotation:
indicates how the ellipse as a whole is rotated relative to the current coordinate system
- large_arc_flag:
If non-zero (true) then draw the larger of the available arcs
- sweep_flag:
If non-zero (true) then draw the arc matching a clock-wise rotation
DrawPathFinish
Synopsis
void DrawPathFinish( DrawContext context );
Description
DrawPathFinish() terminates the current path.
The format of the DrawPathFinish method is:
void DrawPathFinish( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawPathLineToAbsolute
Synopsis
void DrawPathLineToAbsolute( DrawContext context, const double x, const double y );
Description
DrawPathLineToAbsolute() draws a line path from the current point to the given coordinate using absolute coordinates. The coordinate then becomes the new current point.
The format of the DrawPathLineToAbsolute method is:
void DrawPathLineToAbsolute( DrawContext context, const double x, const double y );
- context:
drawing context
- x:
target x ordinate
- y:
target y ordinate
DrawPathLineToRelative
Synopsis
void DrawPathLineToRelative( DrawContext context, const double x, const double y );
Description
DrawPathLineToRelative() draws a line path from the current point to the given coordinate using relative coordinates. The coordinate then becomes the new current point.
The format of the DrawPathLineToRelative method is:
void DrawPathLineToRelative( DrawContext context, const double x, const double y );
- context:
drawing context
- x:
target x ordinate
- y:
target y ordinate
DrawPathLineToHorizontalAbsolute
Synopsis
void DrawPathLineToHorizontalAbsolute( DrawContext context, const double x );
Description
DrawPathLineToHorizontalAbsolute() draws a horizontal line path from the current point to the target point using absolute coordinates. The target point then becomes the new current point.
The format of the DrawPathLineToHorizontalAbsolute method is:
void DrawPathLineToHorizontalAbsolute( DrawContext context, const double x );
- context:
drawing context
- x:
target x ordinate
DrawPathLineToHorizontalRelative
Synopsis
void DrawPathLineToHorizontalRelative( DrawContext context, const double x );
Description
DrawPathLineToHorizontalRelative() draws a horizontal line path from the current point to the target point using relative coordinates. The target point then becomes the new current point.
The format of the DrawPathLineToHorizontalRelative method is:
void DrawPathLineToHorizontalRelative( DrawContext context, const double x );
A description of each parameter follows:
- context:
drawing context
- x:
target x ordinate
DrawPathLineToVerticalAbsolute
Synopsis
void DrawPathLineToVerticalAbsolute( DrawContext context, const double y );
Description
DrawPathLineToVerticalAbsolute() draws a vertical line path from the current point to the target point using absolute coordinates. The target point then becomes the new current point.
The format of the DrawPathLineToVerticalAbsolute method is:
void DrawPathLineToVerticalAbsolute( DrawContext context, const double y );
- context:
drawing context
- y:
target y ordinate
DrawPathLineToVerticalRelative
Synopsis
void DrawPathLineToVerticalRelative( DrawContext context, const double y );
Description
DrawPathLineToVerticalRelative() draws a vertical line path from the current point to the target point using relative coordinates. The target point then becomes the new current point.
The format of the DrawPathLineToVerticalRelative method is:
void DrawPathLineToVerticalRelative( DrawContext context, const double y );
- context:
drawing context
- y:
target y ordinate
DrawPathMoveToAbsolute
Synopsis
void DrawPathMoveToAbsolute( DrawContext context, const double x, const double y );
Description
DrawPathMoveToAbsolute() starts a new sub-path at the given coordinate using absolute coordinates. The current point then becomes the specified coordinate.
The format of the DrawPathMoveToAbsolute method is:
void DrawPathMoveToAbsolute( DrawContext context, const double x, const double y );
- context:
drawing context
- x:
target x ordinate
- y:
target y ordinate
DrawPathMoveToRelative
Synopsis
void DrawPathMoveToRelative( DrawContext context, const double x, const double y );
Description
DrawPathMoveToRelative() starts a new sub-path at the given coordinate using relative coordinates. The current point then becomes the specified coordinate.
The format of the DrawPathMoveToRelative method is:
void DrawPathMoveToRelative( DrawContext context, const double x, const double y );
- context:
drawing context
- x:
target x ordinate
- y:
target y ordinate
DrawPathStart
Synopsis
void DrawPathStart( DrawContext context );
Description
DrawPathStart() declares the start of a path drawing list which is terminated by a matching DrawPathFinish() command. All other DrawPath commands must be enclosed between a DrawPathStart() and a DrawPathFinish() command. This is because path drawing commands are subordinate commands and they do not function by themselves.
The format of the DrawPathStart method is:
void DrawPathStart( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawPeekGraphicContext
Synopsis
DrawInfo *DrawPeekGraphicContext( const DrawContext context );
Description
DrawPeekGraphicContext() returns a copy of the the DrawInfo structure at the head of the drawing context stack. The user is responsible for deallocating the returned object using DestroyDrawInfo.
The format of the DrawPeekGraphicContext method is:
DrawInfo *DrawPeekGraphicContext( const DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawPoint
Synopsis
void DrawPoint( DrawContext context, const double x, const double y );
Description
DrawPoint() draws a point using the current stroke color and stroke thickness at the specified coordinates.
The format of the DrawPoint method is:
void DrawPoint( DrawContext context, const double x, const double y );
A description of each parameter follows:
- context:
drawing context
- x:
target x coordinate
- y:
target y coordinate
DrawPolygon
Synopsis
void DrawPolygon( DrawContext context, const unsigned long num_coords, const PointInfo *coordinates );
Description
DrawPolygon() draws a polygon using the current stroke, stroke width, and fill color or texture, using the specified array of coordinates.
The format of the DrawPolygon method is:
void DrawPolygon( DrawContext context, const unsigned long num_coords, const PointInfo *coordinates );
- context:
drawing context
- num_coords:
number of coordinates
- coordinates:
coordinate array
DrawPolyline
Synopsis
void DrawPolyline( DrawContext context, const unsigned long num_coords, const PointInfo *coordinates );
Description
DrawPolyline() draws a polyline using the current stroke, stroke width, and fill color or texture, using the specified array of coordinates.
The format of the DrawPolyline method is:
void DrawPolyline( DrawContext context, const unsigned long num_coords, const PointInfo *coordinates );
- context:
drawing context
- num_coords:
number of coordinates
- coordinates:
coordinate array
DrawPopClipPath
Synopsis
void DrawPopClipPath( DrawContext context );
Description
DrawPopClipPath() terminates a clip path definition.
The format of the DrawPopClipPath method is:
void DrawPopClipPath( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawPopDefs
Synopsis
void DrawPopDefs( DrawContext context );
Description
DrawPopDefs() terminates a definition list
The format of the DrawPopDefs method is:
void DrawPopDefs( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawPopGraphicContext
Synopsis
void DrawPopGraphicContext( DrawContext context );
Description
DrawPopGraphicContext() destroys the current context returning to the previously pushed context. Multiple contexts may exist. It is an error to attempt to pop more contexts than have been pushed, and it is proper form to pop all contexts which have been pushed.
The format of the DrawPopGraphicContext method is:
void DrawPopGraphicContext( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawPopPattern
Synopsis
void DrawPopPattern( DrawContext context );
Description
DrawPopPattern() terminates a pattern definition.
The format of the DrawPopPattern method is:
void DrawPopPattern( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawPushClipPath
Synopsis
void DrawPushClipPath( DrawContext context, const char *clip_path_id );
Description
DrawPushClipPath() starts a clip path definition which is comprized of any number of drawing commands and terminated by a DrawPopClipPath() command.
The format of the DrawPushClipPath method is:
void DrawPushClipPath( DrawContext context, const char *clip_path_id );
A description of each parameter follows:
- context:
drawing context
- clip_path_id:
string identifier to associate with the clip path for later use.
DrawPushDefs
Synopsis
void DrawPushDefs( DrawContext context );
Description
DrawPushDefs() indicates that commands up to a terminating DrawPopDefs() command create named elements (e.g. clip-paths, textures, etc.) which may safely be processed earlier for the sake of efficiency.
The format of the DrawPushDefs method is:
void DrawPushDefs( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawPushGraphicContext
Synopsis
void DrawPushGraphicContext( DrawContext context );
Description
DrawPushGraphicContext() clones the current drawing context to create a new drawing context. The original drawing context(s) may be returned to by invoking DrawPopGraphicContext(). The contexts are stored on a context stack. For every Pop there must have already been an equivalent Push.
The format of the DrawPushGraphicContext method is:
void DrawPushGraphicContext( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawPushPattern
Synopsis
void DrawPushPattern( DrawContext context, const char *pattern_id, const double x, const double y, const double width, const double height );
Description
DrawPushPattern() indicates that subsequent commands up to a DrawPopPattern() command comprise the definition of a named pattern. The pattern space is assigned top left corner coordinates, a width and height, and becomes its own drawing space. Anything which can be drawn may be used in a pattern definition. Named patterns may be used as stroke or brush definitions.
The format of the DrawPushPattern method is:
void DrawPushPattern( DrawContext context, const char *pattern_id, const double x, const double y, const double width, const double height );
- context:
drawing context
- pattern_id:
pattern identification for later reference
- x:
x ordinate of top left corner
- y:
y ordinate of top left corner
- width:
width of pattern space
- height:
height of pattern space
DrawRectangle
Synopsis
void DrawRectangle( DrawContext context, const double x1, const double y1, const double x2, const double y2 );
Description
DrawRectangle() draws a rectangle given two coordinates and using the current stroke, stroke width, and fill settings.
The format of the DrawRectangle method is:
void DrawRectangle( DrawContext context, const double x1, const double y1, const double x2, const double y2 );
- x1:
x ordinate of first coordinate
- y1:
y ordinate of first coordinate
- x2:
x ordinate of second coordinate
- y2:
y ordinate of second coordinate
DrawRender
Synopsis
int DrawRender( const DrawContext context );
Description
DrawRender() renders all preceding drawing commands onto the image.
The format of the DrawRender method is:
int DrawRender( const DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawRotate
Synopsis
void DrawRotate( DrawContext context, const double degrees );
Description
DrawRotate() applies the specified rotation to the current coordinate space.
The format of the DrawRotate method is:
void DrawRotate( DrawContext context, const double degrees );
A description of each parameter follows:
- context:
drawing context
- degrees:
degrees of rotation
DrawRoundRectangle
Synopsis
void DrawRoundRectangle( DrawContext context, double x1, double y1, double x2, double y2, double rx, double ry );
Description
DrawRoundRectangle() draws a rounted rectangle given two coordinates, x & y corner radiuses and using the current stroke, stroke width, and fill settings.
The format of the DrawRoundRectangle method is:
void DrawRoundRectangle( DrawContext context, double x1, double y1, double x2, double y2, double rx, double ry );
- context:
drawing context
- x1:
x ordinate of first coordinate
- y1:
y ordinate of first coordinate
- x2:
x ordinate of second coordinate
- y2:
y ordinate of second coordinate
- rx:
radius of corner in horizontal direction
- ry:
radius of corner in vertical direction
DrawScale
Synopsis
void DrawScale( DrawContext context, const double x, const double y );
Description
DrawScale() adjusts the scaling factor to apply in the horizontal and vertical directions to the current coordinate space.
The format of the DrawScale method is:
void DrawScale( DrawContext context, const double x, const double y );
A description of each parameter follows:
- context:
drawing context
- x:
horizontal scale factor
- y:
vertical scale factor
DrawSkewX
Synopsis
void DrawSkewX( DrawContext context, const double degrees );
Description
DrawSkewX() skews the current coordinate system in the horizontal direction.
The format of the DrawSkewX method is:
void DrawSkewX( DrawContext context, const double degrees );
A description of each parameter follows:
- context:
drawing context
- degrees:
number of degrees to skew the coordinates
DrawSkewY
Synopsis
void DrawSkewY( DrawContext context, const double degrees );
Description
DrawSkewY() skews the current coordinate system in the vertical direction.
The format of the DrawSkewY method is:
void DrawSkewY( DrawContext context, const double degrees );
A description of each parameter follows:
- context:
drawing context
- degrees:
number of degrees to skew the coordinates
DrawSetStopColor
Synopsis
void DrawSetStopColor( DrawContext context, const PixelPacket *stop_color, const double offset );
Description
DrawSetStopColor() sets the stop color and offset for gradients
The format of the DrawSetStopColor method is:
void DrawSetStopColor( DrawContext context, const PixelPacket *stop_color, const double offset );
- context:
drawing context
o stop_color:
o offset:
DrawGetStrokeColor
Synopsis
PixelPacket DrawGetStrokeColor( DrawContext context );
Description
DrawGetStrokeColor() returns the color used for stroking object outlines.
The format of the DrawGetStrokeColor method is:
PixelPacket DrawGetStrokeColor( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetStrokeColor
Synopsis
void DrawSetStrokeColor( DrawContext context, const PixelPacket *stroke_color );
Description
DrawSetStrokeColor() sets the color used for stroking object outlines.
The format of the DrawSetStrokeColor method is:
void DrawSetStrokeColor( DrawContext context, const PixelPacket *stroke_color );
- context:
drawing context
- stroke_color:
stroke color
DrawSetStrokeColorString
Synopsis
void DrawSetStrokeColorString( DrawContext context, const char *stroke_color );
Description
DrawSetStrokeColorString() sets the color used for stroking object outlines.
The format of the DrawSetStrokeColorString method is:
void DrawSetStrokeColorString( DrawContext context, const char *stroke_color );
- context:
drawing context
- stroke_color:
stroke color
DrawSetStrokePatternURL
Synopsis
void DrawSetStrokePatternURL( DrawContext context, const char *stroke_url );
Description
DrawSetStrokePatternURL() sets the pattern used for stroking object outlines.
The format of the DrawSetStrokePatternURL method is:
void DrawSetStrokePatternURL( DrawContext context, const char *stroke_url );
A description of each parameter follows:
- context:
drawing context
- stroke_url:
URL specifying pattern ID (e.g. "#pattern_id")
DrawGetStrokeAntialias
Synopsis
unsigned int DrawGetStrokeAntialias( DrawContext context );
Description
DrawGetStrokeAntialias() returns the current stroke antialias setting. Stroked outlines are antialiased by default. When antialiasing is disabled stroked pixels are thresholded to determine if the stroke color or underlying canvas color should be used.
The format of the DrawGetStrokeAntialias method is:
unsigned int DrawGetStrokeAntialias( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetStrokeAntialias
Synopsis
void DrawSetStrokeAntialias( DrawContext context, const unsigned int stroke_antialias );
Description
DrawSetStrokeAntialias() controls whether stroked outlines are antialiased. Stroked outlines are antialiased by default. When antialiasing is disabled stroked pixels are thresholded to determine if the stroke color or underlying canvas color should be used.
The format of the DrawSetStrokeAntialias method is:
void DrawSetStrokeAntialias( DrawContext context, const unsigned int stroke_antialias );
- context:
drawing context
- stroke_antialias:
set to false (zero) to disable antialiasing
DrawGetStrokeDashArray
Synopsis
double *DrawGetStrokeDashArray( DrawContext context, unsigned long *num_elems );
Description
DrawGetStrokeDashArray() returns an array representing the pattern of dashes and gaps used to stroke paths (see DrawSetStrokeDashArray). The array must be freed once it is no longer required by the user.
The format of the DrawGetStrokeDashArray method is:
double *DrawGetStrokeDashArray( DrawContext context, unsigned long *num_elems );
A description of each parameter follows:
- context:
drawing context
- number_elements:
address to place number of elements in dash array
DrawSetStrokeDashArray
Synopsis
void DrawSetStrokeDashArray( DrawContext context, const unsigned long num_elems, const double *dasharray );
Description
DrawSetStrokeDashArray() specifies the pattern of dashes and gaps used to stroke paths. The strokeDashArray represents an array of numbers that specify the lengths of alternating dashes and gaps in pixels. If an odd number of values is provided, then the list of values is repeated to yield an even number of values. To remove an existing dash array, pass a zero num_elems argument and null dasharray. A typical stroke dash array might contain the members 5 3 2.
The format of the DrawSetStrokeDashArray method is:
void DrawSetStrokeDashArray( DrawContext context, const unsigned long num_elems, const double *dasharray );
- context:
drawing context
- num_elems:
number of elements in dash array
- dasharray:
dash array values
DrawGetStrokeDashOffset
Synopsis
double DrawGetStrokeDashOffset( DrawContext context );
Description
DrawGetStrokeDashOffset() returns the offset into the dash pattern to start the dash.
The format of the DrawGetStrokeDashOffset method is:
double DrawGetStrokeDashOffset( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetStrokeDashOffset
Synopsis
void DrawSetStrokeDashOffset( DrawContext context, const double dash_offset );
Description
DrawSetStrokeDashOffset() specifies the offset into the dash pattern to start the dash.
The format of the DrawSetStrokeDashOffset method is:
void DrawSetStrokeDashOffset( DrawContext context, const double dash_offset );
- context:
drawing context
- dash_offset:
dash offset
DrawGetStrokeLineCap
Synopsis
LineCap DrawGetStrokeLineCap( DrawContext context );
Description
DrawGetStrokeLineCap() returns the shape to be used at the end of open subpaths when they are stroked. Values of LineCap are UndefinedCap, ButtCap, RoundCap, and SquareCap.
The format of the DrawGetStrokeLineCap method is:
LineCap DrawGetStrokeLineCap( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetStrokeLineCap
Synopsis
void DrawSetStrokeLineCap( DrawContext context, const LineCap linecap );
Description
DrawSetStrokeLineCap() specifies the shape to be used at the end of open subpaths when they are stroked. Values of LineCap are UndefinedCap, ButtCap, RoundCap, and SquareCap.
The format of the DrawSetStrokeLineCap method is:
void DrawSetStrokeLineCap( DrawContext context, const LineCap linecap );
- context:
drawing context
- linecap:
linecap style
DrawGetStrokeLineJoin
Synopsis
LineJoin DrawGetStrokeLineJoin( DrawContext context );
Description
DrawGetStrokeLineJoin() returns the shape to be used at the corners of paths (or other vector shapes) when they are stroked. Values of LineJoin are UndefinedJoin, MiterJoin, RoundJoin, and BevelJoin.
The format of the DrawGetStrokeLineJoin method is:
LineJoin DrawGetStrokeLineJoin( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetStrokeLineJoin
Synopsis
void DrawSetStrokeLineJoin( DrawContext context, const LineJoin linejoin );
Description
DrawSetStrokeLineJoin() specifies the shape to be used at the corners of paths (or other vector shapes) when they are stroked. Values of LineJoin are UndefinedJoin, MiterJoin, RoundJoin, and BevelJoin.
The format of the DrawSetStrokeLineJoin method is:
void DrawSetStrokeLineJoin( DrawContext context, const LineJoin linejoin );
A description of each parameter follows:
- context:
drawing context
- linejoin:
line join style
DrawGetStrokeMiterLimit
Synopsis
unsigned long DrawGetStrokeMiterLimit( DrawContext context );
Description
DrawGetStrokeMiterLimit() returns the miter limit. When two line segments meet at a sharp angle and miter joins have been specified for 'lineJoin', it is possible for the miter to extend far beyond the thickness of the line stroking the path. The miterLimit' imposes a limit on the ratio of the miter length to the 'lineWidth'.
The format of the DrawGetStrokeMiterLimit method is:
unsigned long DrawGetStrokeMiterLimit( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetStrokeMiterLimit
Synopsis
void DrawSetStrokeMiterLimit( DrawContext context, const unsigned long miterlimit );
Description
DrawSetStrokeMiterLimit() specifies the miter limit. When two line segments meet at a sharp angle and miter joins have been specified for 'lineJoin', it is possible for the miter to extend far beyond the thickness of the line stroking the path. The miterLimit' imposes a limit on the ratio of the miter length to the 'lineWidth'.
The format of the DrawSetStrokeMiterLimit method is:
void DrawSetStrokeMiterLimit( DrawContext context, const unsigned long miterlimit );
- context:
drawing context
- miterlimit:
miter limit
DrawGetStrokeOpacity
Synopsis
double DrawGetStrokeOpacity( DrawContext context );
Description
DrawGetStrokeOpacity() returns the opacity of stroked object outlines.
The format of the DrawGetStrokeOpacity method is:
double DrawGetStrokeOpacity( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetStrokeOpacity
Synopsis
void DrawSetStrokeOpacity( DrawContext context, const double stroke_opacity );
Description
DrawSetStrokeOpacity() specifies the opacity of stroked object outlines.
The format of the DrawSetStrokeOpacity method is:
void DrawSetStrokeOpacity( DrawContext context, const double stroke_opacity );
- context:
drawing context
- stroke_opacity:
stroke opacity. The value 1.0 is opaque.
DrawGetStrokeWidth
Synopsis
double DrawGetStrokeWidth( DrawContext context );
Description
DrawGetStrokeWidth() returns the width of the stroke used to draw object outlines.
The format of the DrawGetStrokeWidth method is:
double DrawGetStrokeWidth( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetStrokeWidth
Synopsis
void DrawSetStrokeWidth( DrawContext context, const double stroke_width );
Description
DrawSetStrokeWidth() sets the width of the stroke used to draw object outlines.
The format of the DrawSetStrokeWidth method is:
void DrawSetStrokeWidth( DrawContext context, const double stroke_width );
A description of each parameter follows:
- context:
drawing context
- stroke_width:
stroke width
DrawGetTextAntialias
Synopsis
unsigned int DrawGetTextAntialias( DrawContext context );
Description
DrawGetTextAntialias() returns the current text antialias setting, which determines whether text is antialiased. Text is antialiased by default.
The format of the DrawGetTextAntialias method is:
unsigned int DrawGetTextAntialias( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetTextAntialias
Synopsis
void DrawSetTextAntialias( DrawContext context, const unsigned int text_antialias );
Description
DrawSetTextAntialias() controls whether text is antialiased. Text is antialiased by default.
The format of the DrawSetTextAntialias method is:
void DrawSetTextAntialias( DrawContext context, const unsigned int text_antialias );
- context:
drawing context
- text_antialias:
antialias boolean. Set to false (0) to disable antialiasing.
DrawGetTextDecoration
Synopsis
DecorationType DrawGetTextDecoration( DrawContext context );
Description
DrawGetTextDecoration() returns the decoration applied when annotating with text.
The format of the DrawGetTextDecoration method is:
DecorationType DrawGetTextDecoration( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetTextDecoration
Synopsis
void DrawSetTextDecoration( DrawContext context, const DecorationType decoration );
Description
DrawSetTextDecoration() specifies a decoration to be applied when annotating with text.
The format of the DrawSetTextDecoration method is:
void DrawSetTextDecoration( DrawContext context, const DecorationType decoration );
- context:
drawing context
- decoration:
text decoration. One of NoDecoration, UnderlineDecoration, OverlineDecoration, or LineThroughDecoration
DrawGetTextEncoding
Synopsis
char *DrawGetTextEncoding( DrawContext context );
Description
DrawGetTextEncoding() returns a null-terminated string which specifies the code set used for text annotations. The string must be freed by the user once it is no longer required.
The format of the DrawGetTextEncoding method is:
char *DrawGetTextEncoding( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetTextEncoding
Synopsis
void DrawSetTextEncoding( DrawContext context, const char *encoding );
Description
DrawSetTextEncoding() specifies specifies the code set to use for text annotations. The only character encoding which may be specified at this time is "UTF-8" for representing Unicode as a sequence of bytes. Specify an empty string to set text encoding to the system's default. Successful text annotation using Unicode may require fonts designed to support Unicode.
The format of the DrawSetTextEncoding method is:
void DrawSetTextEncoding( DrawContext context, const char *encoding );
A description of each parameter follows:
- context:
drawing context
- encoding:
character string specifying text encoding
DrawGetTextUnderColor
Synopsis
PixelPacket DrawGetTextUnderColor( DrawContext context );
Description
DrawGetTextUnderColor() returns the color of a background rectangle to place under text annotations.
The format of the DrawGetTextUnderColor method is:
PixelPacket DrawGetTextUnderColor( DrawContext context );
A description of each parameter follows:
- context:
drawing context
DrawSetTextUnderColor
Synopsis
void DrawSetTextUnderColor( DrawContext context, const PixelPacket *under_color );
Description
DrawSetTextUnderColor() specifies the color of a background rectangle to place under text annotations.
The format of the DrawSetTextUnderColor method is:
void DrawSetTextUnderColor( DrawContext context, const PixelPacket *under_color );
- context:
drawing context
- under_color:
text under color
DrawSetTextUnderColorString
Synopsis
void DrawSetTextUnderColorString( DrawContext context, const char *under_color );
Description
DrawSetTextUnderColorString() specifies the color of a background rectangle to place under text annotations.
The format of the DrawSetTextUnderColorString method is:
void DrawSetTextUnderColorString( DrawContext context, const char *under_color );
- context:
drawing context
- under_color:
text under color
DrawTranslate
Synopsis
void DrawTranslate( DrawContext context, const double x, const double y );
Description
DrawTranslate() applies a translation to the current coordinate system which moves the coordinate system origin to the specified coordinate.
The format of the DrawTranslate method is:
void DrawTranslate( DrawContext context, const double x, const double y );
- context:
drawing context
- x:
new x ordinate for coordinate system origin
- y:
new y ordinate for coordinate system origin
DrawSetViewbox
Synopsis
void DrawSetViewbox( DrawContext context, unsigned long x1, unsigned long y1, unsigned long x2, unsigned long y2 );
Description
DrawSetViewbox() sets the overall canvas size to be recorded with the drawing vector data. Usually this will be specified using the same size as the canvas image. When the vector data is saved to SVG or MVG formats, the viewbox is use to specify the size of the canvas image that a viewer will render the vector data on.
The format of the DrawSetViewbox method is:
void DrawSetViewbox( DrawContext context, unsigned long x1, unsigned long y1, unsigned long x2, unsigned long y2 );
- context:
drawing context
- x1:
left x ordinate
- y1:
top y ordinate
- x2:
right x ordinate
- y2:
bottom y ordinate