Package org.eclipse.swt.graphics

Class Path

java.lang.Object
org.eclipse.swt.graphics.Resource
org.eclipse.swt.graphics.Path
public class Path extends Resource
Instances of this class represent paths through the two-dimensional coordinate system. Paths do not have to be continuous, and can be described using lines, rectangles, arcs, cubic or quadratic bezier curves, glyphs, or other paths.

Application code must explicitly invoke the Path.dispose() method to release the operating system resources managed by each instance when those instances are no longer required.

Since:
2.1

  • Constructor Summary

    Constructors
    Constructor
    Description
    Path(Device device)
    Constructs a new empty Path.
    Path(Device device, PathData data)
    Constructs a new Path with the specified PathData.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    addPath(Path path)
    Adds to the receiver the path described by the parameter.
    void
    addRectangle(float x, float y, float width, float height)
    Adds to the receiver the rectangle specified by x, y, width and height.
    void
    close()
    Closes the current sub path by adding to the receiver a line from the current point of the path back to the starting point of the sub path.
    void
    cubicTo(float cx1, float cy1, float cx2, float cy2, float x, float y)
    Adds to the receiver a cubic bezier curve based on the parameters.
    void
    getCurrentPoint(float[] point)
    Replaces the first two elements in the parameter with values that describe the current point of the path.
    PathData
    getPathData()
    Returns a device independent representation of the receiver.
    void
    lineTo(float x, float y)
    Adds to the receiver a line from the current point to the point specified by (x, y).
    void
    moveTo(float x, float y)
    Sets the current point of the receiver to the point specified by (x, y).
    void
    quadTo(float cx, float cy, float x, float y)
    Adds to the receiver a quadratic curve based on the parameters.

    Methods inherited from class org.eclipse.swt.graphics.Resource

    dispose, getDevice, isDisposed

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Constructor Details

    • Path

      public Path(Device device)
      Constructs a new empty Path.

      This operation requires the operating system's advanced graphics subsystem which may not be available on some platforms.

      Parameters:
      device - the device on which to allocate the path
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the device is null and there is no current device
      SWTException -
      • ERROR_NO_GRAPHICS_LIBRARY - if advanced graphics are not available
      SWTError -
      • ERROR_NO_HANDLES if a handle for the path could not be obtained
      See Also:

    • Path

      public Path(Device device, PathData data)
      Constructs a new Path with the specified PathData.

      This operation requires the operating system's advanced graphics subsystem which may not be available on some platforms.

      Parameters:
      device - the device on which to allocate the path
      data - the data for the path
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the device is null and there is no current device
      • ERROR_NULL_ARGUMENT - if the data is null
      SWTException -
      • ERROR_NO_GRAPHICS_LIBRARY - if advanced graphics are not available
      SWTError -
      • ERROR_NO_HANDLES if a handle for the path could not be obtained
      See Also:

  • Method Details

    • addPath

      public void addPath(Path path)
      Adds to the receiver the path described by the parameter.
      Parameters:
      path - the path to add to the receiver
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the parameter is null
      • ERROR_INVALID_ARGUMENT - if the parameter has been disposed
      SWTException -
      • ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed

    • addRectangle

      public void addRectangle(float x, float y, float width, float height)
      Adds to the receiver the rectangle specified by x, y, width and height.
      Parameters:
      x - the x coordinate of the rectangle to add
      y - the y coordinate of the rectangle to add
      width - the width of the rectangle to add
      height - the height of the rectangle to add
      Throws:
      SWTException -
      • ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed

    • moveTo

      public void moveTo(float x, float y)
      Sets the current point of the receiver to the point specified by (x, y). Note that this starts a new sub path.
      Parameters:
      x - the x coordinate of the new end point
      y - the y coordinate of the new end point
      Throws:
      SWTException -
      • ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed

    • lineTo

      public void lineTo(float x, float y)
      Adds to the receiver a line from the current point to the point specified by (x, y).
      Parameters:
      x - the x coordinate of the end of the line to add
      y - the y coordinate of the end of the line to add
      Throws:
      SWTException -
      • ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed

    • quadTo

      public void quadTo(float cx, float cy, float x, float y)
      Adds to the receiver a quadratic curve based on the parameters.
      Parameters:
      cx - the x coordinate of the control point of the spline
      cy - the y coordinate of the control point of the spline
      x - the x coordinate of the end point of the spline
      y - the y coordinate of the end point of the spline
      Throws:
      SWTException -
      • ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed

    • cubicTo

      public void cubicTo(float cx1, float cy1, float cx2, float cy2, float x, float y)
      Adds to the receiver a cubic bezier curve based on the parameters.
      Parameters:
      cx1 - the x coordinate of the first control point of the spline
      cy1 - the y coordinate of the first control of the spline
      cx2 - the x coordinate of the second control of the spline
      cy2 - the y coordinate of the second control of the spline
      x - the x coordinate of the end point of the spline
      y - the y coordinate of the end point of the spline
      Throws:
      SWTException -
      • ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed

    • close

      public void close()
      Closes the current sub path by adding to the receiver a line from the current point of the path back to the starting point of the sub path.
      Throws:
      SWTException -
      • ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed

    • getPathData

      public PathData getPathData()
      Returns a device independent representation of the receiver.
      Returns:
      the PathData for the receiver
      Throws:
      SWTException -
      • ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed
      See Also:

    • getCurrentPoint

      public void getCurrentPoint(float[] point)
      Replaces the first two elements in the parameter with values that describe the current point of the path.
      Parameters:
      point - the array to hold the result
      Throws:
      IllegalArgumentException -
      • ERROR_NULL_ARGUMENT - if the parameter is null
      • ERROR_INVALID_ARGUMENT - if the parameter is too small to hold the end point
      SWTException -
      • ERROR_GRAPHIC_DISPOSED - if the receiver has been disposed