PathBuilder

Class
Common
class PathBuilder

PathBuilder provides a fluent API to creates a list of PathNode, used to describe a path.

Properties

Common
val nodes: List<PathNode>

Returns the list of PathNode currently held in this builder.

Functions

fun close(): PathBuilder

Closes the current contour by adding a PathNode.Close to nodes.

fun moveTo(x: Float, y: Float): PathBuilder

Start a new contour at position (x, y) by adding a PathNode.MoveTo to nodes.

Parameters
x The x coordinate of the start of the new contour
y The y coordinate of the start of the new contour 
fun moveToRelative(dx: Float, dy: Float): PathBuilder

Start a new contour at the offset (dx, dy) relative to the last path position by adding a PathNode.RelativeMoveTo to nodes.

Parameters
dx The x offset of the start of the new contour, relative to the last path position
dy The y offset of the start of the new contour, relative to the last path position 
fun lineTo(x: Float, y: Float): PathBuilder

Add a line from the last point to the position (x, y) by adding a PathNode.LineTo to nodes. If no contour has been created by calling moveTo first, the origin of the line is set to (0, 0).

Parameters
x The x coordinate of the end of the line
y The y coordinate of the end of the line 
fun lineToRelative(dx: Float, dy: Float): PathBuilder

Add a line from the last point to the offset (dx, dy) relative to the last point by adding a PathNode.RelativeLineTo to nodes. If no contour has been created by calling moveTo first, the origin of the line is set to (0, 0).

Parameters
dx The x offset of the end of the line, relative to the last path position
dy The y offset of the end of the line, relative to the last path position 
fun horizontalLineTo(x: Float): PathBuilder

Add a line from the last point to the position (x, oy), where oy is the y coordinate of the last point, by adding a PathNode.HorizontalTo to nodes. If no contour has been created by calling moveTo first, the origin of the line is set to (0, 0).

Parameters
x The x coordinate of the end of the line 
fun horizontalLineToRelative(dx: Float): PathBuilder

Add a line from the last point to the position (dx + ox, oy), where ox and oy are the x and y coordinates of the last point, by adding a PathNode.RelativeHorizontalTo to nodes. If no contour has been created by calling moveTo first, the origin of the line is set to (0, 0).

Parameters
dx The x offset of the end of the line, relative to the last path position 
fun verticalLineTo(y: Float): PathBuilder

Add a line from the last point to the position (ox, y), where ox is the x coordinate of the last point, by adding a PathNode.VerticalTo to nodes. If no contour has been created by calling moveTo first, the origin of the line is set to (0, 0).

Parameters
y The y coordinate of the end of the line 
fun verticalLineToRelative(dy: Float): PathBuilder

Add a line from the last point to the position (ox, dy + oy), where ox and oy are the x and y coordinates of the last point, by adding a PathNode.RelativeVerticalTo to nodes. If no contour has been created by calling moveTo first, the origin of the line is set to (0, 0).

Parameters
dy The y offset of the end of the line, relative to the last path position 
fun curveTo(x1: Float, y1: Float, x2: Float, y2: Float, x3: Float, y3: Float): PathBuilder

Add a cubic Bézier from the last point to the position (x3, y3), approaching the control points (x1, y1) and (x2, y2), by adding a PathNode.CurveTo to nodes. If no contour has been created by calling moveTo first, the origin of the curve is set to (0, 0).

Parameters
x1 The x coordinate of the first control point of the cubic curve
y1 The y coordinate of the first control point of the cubic curve
x2 The x coordinate of the second control point of the cubic curve
y2 The y coordinate of the second control point of the cubic curve
x3 The x coordinate of the end point of the cubic curve
y3 The y coordinate of the end point of the cubic curve 
fun curveToRelative(
        dx1: Float,
        dy1: Float,
        dx2: Float,
        dy2: Float,
        dx3: Float,
        dy3: Float,
    ): PathBuilder

Add a cubic Bézier by adding a PathNode.CurveTo to nodes. If no contour has been created by calling moveTo first, the origin of the curve is set to (0, 0). The cubic Bézier control and end points are defined by offsets relative to the last point.

Parameters
dx1 The x offset of the first control point of the cubic curve, relative to the last path position
dy1 The y offset of the first control point of the cubic curve, relative to the last path position
dx2 The x offset of the second control point of the cubic curve, relative to the last path position
dy2 The y offset of the second control point of the cubic curve, relative to the last path position
dx3 The x offset of the end point of the cubic curve, relative to the last path position
dy3 The y offset of the end point of the cubic curve, relative to the last path position 
fun reflectiveCurveTo(x1: Float, y1: Float, x2: Float, y2: Float): PathBuilder

Add a cubic Bézier from the last point to the position (x2, y2). The first control point is the reflection of the second control point of the previous command. If there is no previous command or the previous command is not a cubic Bézier, the first control point is set to the last path position. The second control point is defined by (x1, y1). Calling this method adds a PathNode.ReflectiveCurveTo to nodes. If no contour has been created by calling moveTo first, the origin of the curve is set to (0, 0).

Parameters
x1 The x coordinate of the second control point of the cubic curve
y1 The y coordinate of the second control point of the cubic curve
x2 The x coordinate of the end point of the cubic curve
y2 The y coordinate of the end point of the cubic curve 
fun reflectiveCurveToRelative(dx1: Float, dy1: Float, dx2: Float, dy2: Float): PathBuilder

Add a cubic Bézier by adding a PathNode.RelativeReflectiveCurveTo to nodes. If no contour has been created by calling moveTo first, the origin of the curve is set to (0, 0). The cubic Bézier second control point and end points are defined by offsets relative to the last point. The reflective nature of the curve is described in reflectiveCurveTo.

Parameters
dx1 The x offset of the second control point of the cubic curve, relative to the last path position
dy1 The y offset of the second control point of the cubic curve, relative to the last path position
dx2 The x offset of the end point of the cubic curve, relative to the last path position
dy2 The y offset of the end point of the cubic curve, relative to the last path position 
fun quadTo(x1: Float, y1: Float, x2: Float, y2: Float): PathBuilder

Add a quadratic Bézier from the last point to the position (x2, y2), approaching the control point (x1, y1), by adding a PathNode.QuadTo to nodes. If no contour has been created by calling moveTo first, the origin of the curve is set to (0, 0).

Parameters
x1 The x coordinate of the control point of the quadratic curve
y1 The y coordinate of the control point of the quadratic curve
x2 The x coordinate of the end point of the quadratic curve
y2 The y coordinate of the end point of the quadratic curve 
fun quadToRelative(dx1: Float, dy1: Float, dx2: Float, dy2: Float): PathBuilder

Add a quadratic Bézier by adding a PathNode.RelativeQuadTo to nodes. If no contour has been created by calling moveTo first, the origin of the curve is set to (0, 0). The control point and end point of the curve are defined by offsets relative to the last point.

Parameters
dx1 The x offset of the control point of the quadratic curve, relative to the last path position
dy1 The y offset of the control point of the quadratic curve, relative to the last path position
dx2 The x offset of the end point of the quadratic curve, relative to the last path position
dy2 The y offset of the end point of the quadratic curve, relative to the last path position 
fun reflectiveQuadTo(x1: Float, y1: Float): PathBuilder

Add a quadratic Bézier from the last point to the position (x1, y1). The control point is the reflection of the control point of the previous command. If there is no previous command or the previous command is not a quadratic Bézier, the control point is set to the last path position. Calling this method adds a PathNode.ReflectiveQuadTo to nodes. If no contour has been created by calling moveTo first, the origin of the curve is set to (0, 0).

Parameters
x1 The x coordinate of the end point of the quadratic curve
y1 The y coordinate of the end point of the quadratic curve 
fun reflectiveQuadToRelative(dx1: Float, dy1: Float): PathBuilder

Add a quadratic Bézier by adding a PathNode.RelativeReflectiveQuadTo to nodes. If no contour has been created by calling moveTo first, the origin of the curve is set to (0, 0). The quadratic Bézier end point is defined by an offset relative to the last point. The reflective nature of the curve is described in reflectiveQuadTo.

Parameters
dx1 The x offset of the end point of the quadratic curve, relative to the last path position
dy1 The y offset of the end point of the quadratic curve, relative to the last path position 
fun arcTo(
        horizontalEllipseRadius: Float,
        verticalEllipseRadius: Float,
        theta: Float,
        isMoreThanHalf: Boolean,
        isPositiveArc: Boolean,
        x1: Float,
        y1: Float,
    ): PathBuilder

Add an elliptical arc from the last point to the position (x1, y1) by adding PathNode.ArcTo to nodes. If no contour has been created by calling moveTo first, the origin of the arc is set to (0, 0).

The ellipse is defined by 3 parameters:

  • horizontalEllipseRadius and verticalEllipseRadius to define the size of the ellipse
  • theta to define the orientation (as an X-axis rotation) of the ellipse

In most situations, there are four arc candidates that can be drawn from the origin to (x1, y1). Which of the arcs is used is influenced by isMoreThanHalf and isPositiveArc.

When isMoreThanHalf is set to true, the added arc will be chosen amongst the two candidates that represent an arc sweep greater than or equal to 180 degrees.

When isPositiveArc is set to true, the added arc will be chosen amongst the two candidates with a positive-angle direction (counter-clockwise)

Parameters
horizontalEllipseRadius The horizontal radius of the ellipse
verticalEllipseRadius The vertical radius of the ellipse
theta The rotation of the ellipse around the X-axis, in degrees
isMoreThanHalf Defines whether to use an arc candidate with a sweep greater than or equal to 180 degrees
isPositiveArc Defines whether to use an arc candidate that's counter-clockwise or not
x1 The x coordinate of the end point of the arc
y1 The y coordinate of the end point of the arc 
fun arcToRelative(
        a: Float,
        b: Float,
        theta: Float,
        isMoreThanHalf: Boolean,
        isPositiveArc: Boolean,
        dx1: Float,
        dy1: Float,
    ): PathBuilder

Add an elliptical arc by adding PathNode.RelativeArcTo to nodes. If no contour has been created by calling moveTo first, the origin of the arc is set to (0, 0). The arc Bézier end point is defined by an offset relative to the last point.

The ellipse is defined by 3 parameters:

  • a and b to define the size of the ellipse
  • theta to define the orientation (as an X-axis rotation) of the ellipse

In most situations, there are four arc candidates that can be drawn from the origin to the end point. Which of the arcs is used is influenced by isMoreThanHalf and isPositiveArc.

When isMoreThanHalf is set to true, the added arc will be chosen amongst the two candidates that represent an arc sweep greater than or equal to 180 degrees.

When isPositiveArc is set to true, the added arc will be chosen amongst the two candidates with a positive-angle direction (counter-clockwise)

Parameters
a The horizontal radius of the ellipse
b The vertical radius of the ellipse
theta The rotation of the ellipse around the X-axis, in degrees
isMoreThanHalf Defines whether to use an arc candidate with a sweep greater than or equal to 180 degrees
isPositiveArc Defines whether to use an arc candidate that's counter-clockwise or not
dx1 The x offset of the end point of the arc, relative to the last path position
dy1 The y offset of the end point of the arc, relative to the last path position