com.reportmill.graphics

Class RMDoubleStroke

java.lang.Object

SnapObject

com.reportmill.graphics.RMFill

com.reportmill.graphics.RMStroke

com.reportmill.graphics.RMDoubleStroke

public class RMDoubleStroke
extends RMStroke

Strokes a path with 2 lines of different widths, with an arbitrary separation (d) between them. This works by taking the input path and creating 'offset curves'. The offset curve is defined as being parallel to the original curve at every point. For a given parametric curve C(t)={x(t),y(t)}, the slope of the curve at t is given by mC(t)=(dy/dt) / (dx/dt) = y'(t)/x'(t) and the the normal is therefore NC(t)=Normalize({-x'(t), y'(t)}) An offset curve for a cubic bezier can not be represented by a single bezier. Therefore, we need to find a set of n curves OffC0,OffC1,...OffCn that fits, as closely as possible, the following points: OffsetPoint(t)=C(t)+d*NC(t) One possibility is to calculate a million OffsetPoints for the range t->{0,1} and run the curve fit code. In order to preserve continuity of the different bezier segments, it should also be required that mOffC0(0) = mC(0) and mOffCn(1) = mC(1) That is, the slopes at the beginning and end of the curve should the same in the offset curve as it is in the original curve. Also, since the offset points are obtained by walking along the normal vector for the original curve, the slope of the offset curve at offsetpoint(t) should be the same as mC(t). The curve fit code does not currently take into account the slope of the curve at a given input point, but it's something to look into. Knowing this may provide enough additional information to speed up the curve fit and/or reduce the number of input points needed for an accurate fit.

Field Summary

Fields

Modifier and Type	Field and Description
static int	INNER_RULE_ON_PATH
static int	OUTER_RULE_ON_PATH
static int	RULE_GAP_ON_PATH
static int	RULES_CENTERED_ABOUT_PATH

Constructor Summary

Constructors

Constructor and Description
RMDoubleStroke() Creates a new plain double stroke.
RMDoubleStroke(RMColor col, float w) Creates a new double stroke.
RMDoubleStroke(RMColor col, float outerW, float innerW, float separation, int positions) Creates a new double stroke.

Method Summary

Modifier and Type	Method and Description
RMDoubleStroke	clone() Standard clone implementation.
boolean	equals(java.lang.Object anObj) Standard equals implementation.
java.lang.Object	fromXML(XMLArchiver anArchiver, XMLElement anElement) XML unarchival.
RMRect	getBounds(RMShape aShape) Returns the bounds required to render this fill for this shape.
float	getInnerRuleWidth() Returns the inner rule width.
RMStroke	getInnerStroke() Return the stroke used on the inside of a clockwise path
float	getOuterRuleWidth() Returns the outer rule width.
RMStroke	getOuterStroke() Return the stroke used on the outside of a clockwise path
int	getRulePositions() Returns the double stroke rule positions.
void	paint(RMShapePainter aPntr, RMShape aShape) Override to paint inner and outer strokes.
XMLElement	toXML(XMLArchiver anArchiver) XML archival.

Methods inherited from class com.reportmill.graphics.RMStroke

getDashArray, getDashArray, getDashArrayString, getDashArrayString, getDashPhase, getName, getStrokePath, getWidth, setColor, setDashArray, setDashArrayString, setDashPhase, setWidth

Methods inherited from class com.reportmill.graphics.RMFill

deriveFill, getColor, hasAlpha, toString

Methods inherited from class java.lang.Object

getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

OUTER_RULE_ON_PATH

public static final int OUTER_RULE_ON_PATH

See Also:

Constant Field Values

INNER_RULE_ON_PATH

public static final int INNER_RULE_ON_PATH

See Also:

Constant Field Values

RULES_CENTERED_ABOUT_PATH

public static final int RULES_CENTERED_ABOUT_PATH

See Also:

Constant Field Values

RULE_GAP_ON_PATH

public static final int RULE_GAP_ON_PATH

See Also:

Constant Field Values

Constructor Detail

RMDoubleStroke

public RMDoubleStroke()

Creates a new plain double stroke.

RMDoubleStroke

public RMDoubleStroke(RMColor col,
                      float w)

Creates a new double stroke.

RMDoubleStroke

public RMDoubleStroke(RMColor col,
                      float outerW,
                      float innerW,
                      float separation,
                      int positions)

Creates a new double stroke.

Method Detail

getRulePositions

public int getRulePositions()

Returns the double stroke rule positions.

getInnerRuleWidth

public float getInnerRuleWidth()

Returns the inner rule width.

getOuterRuleWidth

public float getOuterRuleWidth()

Returns the outer rule width.

getOuterStroke

public RMStroke getOuterStroke()

Return the stroke used on the outside of a clockwise path

getInnerStroke

public RMStroke getInnerStroke()

Return the stroke used on the inside of a clockwise path

getBounds

public RMRect getBounds(RMShape aShape)

Returns the bounds required to render this fill for this shape.

Overrides:

getBounds in class RMStroke

paint

public void paint(RMShapePainter aPntr,
                  RMShape aShape)

Override to paint inner and outer strokes.

Overrides:

paint in class RMStroke

equals

public boolean equals(java.lang.Object anObj)

Standard equals implementation.

Overrides:

equals in class RMStroke

clone

public RMDoubleStroke clone()

Standard clone implementation.

Overrides:

clone in class RMStroke

toXML

public XMLElement toXML(XMLArchiver anArchiver)

XML archival.

Overrides:

toXML in class RMStroke

fromXML

public java.lang.Object fromXML(XMLArchiver anArchiver,
                                XMLElement anElement)

XML unarchival.

Overrides:

fromXML in class RMStroke