public class RotatedTextUtils extends Object
A convenience class to easily draw rotated text which is positioned on a specific side of the rotation point (TOP, BOTTOM, LEFT or RIGHT). The text can be anchored by its central point or by the text corner.
The following diagrams illustrate the behaviour of each positioning and anchor point in relation to the rotation point:
top center: top corner:
o o
l l
l l
e e
h h
. .
right center: right corner:
o
l
o l
l e
. l .h
e
h
The class provides 2 separate families of methods:
draw family of methods can be considered a simpler, higher level
API, while the getPosition family is conceptually more complex but faster for some
scenarios.
Example of draw method usage:
// draw coordinates axis Graphics2D g = ... Point2D origin1 = new Point2D.Double(100, 200); int lenght = 100; g.drawLine((int)origin1.getX()-length, (int)origin1.getY(), (int)origin1.getX()+length, (int)origin1.getY()); g.drawLine((int)origin1.getX(), (int)origin1.getY()-length, (int)origin1.getX(), (int)origin1.getY()+length); // draw the rotated text RotatedTextUtils.draw(origin1, g, "Hello world", angle, RotatedTextUtils.PLACEMENT_BOTTOM, RotatedTextUtils.ANCHOR_CORNER);
Example of getPosition method usage:
// draw coordinates axis
Graphics2D g = ...
AffineTransform defaultAt = g.getTransform();
Point2D origin1 = new Point2D.Double(100, 200);
Point2D origin2 = new Point2D.Double(200, 200);
int lenght = 100;
g.drawLine((int)origin1.getX()-length, (int)origin1.getY(), (int)origin1.getX()+length, (int)origin1.getY());
g.drawLine((int)origin1.getX(), (int)origin1.getY()-length, (int)origin1.getX(), (int)origin1.getY()+length);
// draw the rotated text
AffineTransform finalTransform = g.getTransform();
finalTransform.rotate(angle);
g.setTransform(finalTransform);
TextLayout text = new TextLayout("Hello world", g.getFont(), g.getFontRenderContext());
Point2D p = RotatedTextUtils.getPosition(origin1, angle, text, RotatedTextUtils.PLACEMENT_BOTTOM, RotatedTextUtils.ANCHOR_CORNER);
text.draw(g, (float)p.getX(), (float)p.getY());
// faster than RotatedTextUtils.draw if we are writing the same rotated text at different points
p = RotatedTextUtils.getPosition(origin2, angle, text, RotatedTextUtils.PLACEMENT_BOTTOM, RotatedTextUtils.ANCHOR_CORNER);
text.draw(g, (float)p.getX(), (float)p.getY());
g.setTransform(defaultAt);
| Modifier and Type | Field and Description |
|---|---|
static int |
ANCHOR_CENTER
Anchor the center of the text on the rotation center.
|
static int |
ANCHOR_CORNER
Anchor a corner of the text on the rotation center.
|
static int |
PLACEMENT_BOTTOM
Place the text bellow the rotation point, meaning that no part
of the text is over the rotation point.
|
static int |
PLACEMENT_LEFT
Place the text on the left of the rotation point, meaning that no part
of the text is on the right the rotation point.
|
static int |
PLACEMENT_RIGHT
Place the text on the right of the rotation point, meaning that no part
of the text is on the left the rotation point.
|
static int |
PLACEMENT_TOP
Place the text on the top of the rotation point, meaning that no part
of the text is under the rotation point.
|
| Constructor and Description |
|---|
RotatedTextUtils() |
| Modifier and Type | Method and Description |
|---|---|
static void |
draw(Point2D origin,
Graphics2D g,
String strText,
double angle,
int relativePosition,
int anchor)
Draws rotated text which is positioned on
a specific side of the rotation point (TOP, BOTTOM, LEFT or RIGHT).
|
static void |
drawRotated(Point2D location,
Graphics2D g,
String strText,
double angle)
Draws the provided text rotated by angle radians using location as rotation center
without any positioning or anchoring adjustments.
|
static Point2D |
getPosition(Point2D origin,
TextLayout text,
double angle,
int relativePosition,
int anchor)
Gets the position in which the text should be drawn according to the
provided origin point, angle, align and anchor.
|
static Point2D |
getPositionBottomCenter(Point2D origin,
TextLayout text,
double angle)
Gets the position in which the text should be drawn according to the
provided origin point and angle, placing the text at the bottom of the
point and using the center of the text as anchor.
|
static Point2D |
getPositionBottomCorner(Point2D origin,
TextLayout text,
double angle)
Gets the position in which the text should be drawn according to the
provided origin point and angle, placing the text at the bottom of the
point and using a corner of the text as anchor.
|
static Point2D |
getPositionLeftCenter(Point2D origin,
TextLayout text,
double angle)
Gets the position in which the text should be drawn according to the
provided origin point and angle, placing the text at the left of the
point and using the center of the text as anchor.
|
static Point2D |
getPositionLeftCorner(Point2D origin,
TextLayout text,
double angle)
Gets the position in which the text should be drawn according to the
provided origin point and angle, placing the text at the left of the
point and using a corner of the text as anchor.
|
static Point2D |
getPositionRightCenter(Point2D origin,
TextLayout text,
double angle)
Gets the position in which the text should be drawn according to the
provided origin point and angle, placing the text at the right of the
point and using the center of the text as anchor.
|
static Point2D |
getPositionRightCorner(Point2D origin,
TextLayout text,
double angle)
Gets the position in which the text should be drawn according to the
provided origin point and angle, placing the text at the right of the
point and using a corner of the text as anchor.
|
static Point2D |
getPositionTopCenter(Point2D origin,
TextLayout text,
double angle)
Gets the position in which the text should be drawn according to the
provided origin point and angle, placing the text at the top of the
point and using the center of the text as anchor.
|
static Point2D |
getPositionTopCorner(Point2D origin,
TextLayout text,
double angle)
Gets the position in which the text should be drawn according to the
provided origin point and angle, placing the text at the top of the
point and using a corner of the text as anchor.
|
static double |
normalizeAngle(double angle)
Normalizes an angle, in radians.
|
public static final int ANCHOR_CORNER
public static final int ANCHOR_CENTER
public static final int PLACEMENT_TOP
public static final int PLACEMENT_BOTTOM
public static final int PLACEMENT_LEFT
public static final int PLACEMENT_RIGHT
public static void draw(Point2D origin, Graphics2D g, String strText, double angle, int relativePosition, int anchor)
origin - The rotation center pointg - The target Graphics2DstrText - The text to draw .Use the Graphics2D options (font,
color, etc) to style the text before calling this method.angle - The rotation angle, in radians. The angle should be comprised
in the [0, 2*PI[ range, result is otherwise unexpected
(a convenience method is provided to normalize it:
normalizeAngle(double))relativePosition - The position of the text compared with the origin point.
See PLACEMENT_TOP, PLACEMENT_LEFT, PLACEMENT_RIGHT and
1.anchor - Whether the center of the label should be aligned with the
point (ANCHOR_CENTER) or a corner of the label should be used
(ANCHOR_CORNER).public static Point2D getPosition(Point2D origin, TextLayout text, double angle, int relativePosition, int anchor)
Gets the position in which the text should be drawn according to the provided origin point, angle, align and anchor.
You may consider using
the higher level draw methods (e.g. draw(Point2D, Graphics2D, String, double, int, int),
#drawTopCenter(Point2D, Graphics2D, String, double), etc) if
you are drawing a single label, as this method makes some assumptions
for getting maximum performance when drawing several texts using the
same rotation. In particular, this method assumes that the target
Graphics2D has been rotated using the provided angle and the text
has been laid out for this rotated target Graphics2D.
This method deals with coordinates in 2 different coordinate spaces (the original, non-rotated space and the rotated space). The origin point coordinates has to be referred to the non-rotated space, while the returned position is referred to the rotated space.
origin - The point used as the center of the rotationtext - The text to be positioned, which has to be prepared for
a rotated graphics, matching the rotation angleangle - The rotation angle, in radians. The angle should be comprised
in the [0, 2*PI[ range, result is otherwise unexpected
(a convenience method is provided to normalize it:
normalizeAngle(double)relativePosition - The position of the text compared with the origin point.
See PLACEMENT_TOP, PLACEMENT_LEFT, PLACEMENT_RIGHT and
1.anchor - Whether the center of the label should be aligned with the
point (ANCHOR_CENTER) or a corner of the label should be used
(ANCHOR_CORNER).public static Point2D getPositionTopCorner(Point2D origin, TextLayout text, double angle)
Gets the position in which the text should be drawn according to the provided origin point and angle, placing the text at the top of the point and using a corner of the text as anchor.
This method deals with coordinates in 2 different coordinate spaces (the original, non-rotated space and the rotated space). The origin point coordinates has to be referred to the non-rotated space, while the returned position is referred to the rotated space.
origin - The center point of the rotationtext - The text to be drawn, created for the rotated Graphics2Dangle - The rotation angle, in radians. Angle is assumed to be normalized (see
normalizeAngle(double))NoninvertibleTransformExceptionRotatedTextUtils#getPosition(Point2D, double, TextLayout, int, int)},
PLACEMENT_TOP,
ANCHOR_CORNERpublic static Point2D getPositionTopCenter(Point2D origin, TextLayout text, double angle)
Gets the position in which the text should be drawn according to the provided origin point and angle, placing the text at the top of the point and using the center of the text as anchor.
This method deals with coordinates in 2 different coordinate spaces (the original, non-rotated space and the rotated space). The origin point coordinates has to be referred to the non-rotated space, while the returned position is referred to the rotated space.
origin - The center point of the rotationtext - The text to be drawn, created for the rotated Graphics2Dangle - The rotation angle, in radians. Angle is assumed to be normalized (see
normalizeAngle(double))NoninvertibleTransformExceptionRotatedTextUtils#getPosition(Point2D, double, TextLayout, int, int)},
PLACEMENT_TOP,
ANCHOR_CENTERpublic static Point2D getPositionRightCorner(Point2D origin, TextLayout text, double angle)
Gets the position in which the text should be drawn according to the provided origin point and angle, placing the text at the right of the point and using a corner of the text as anchor.
This method deals with coordinates in 2 different coordinate spaces (the original, non-rotated space and the rotated space). The origin point coordinates has to be referred to the non-rotated space, while the returned position is referred to the rotated space.
origin - The center point of the rotationtext - The text to be drawn, created for the rotated Graphics2Dangle - The rotation angle, in radians. Angle is assumed to be normalized (see
normalizeAngle(double))NoninvertibleTransformExceptionRotatedTextUtils#getPosition(Point2D, double, TextLayout, int, int)},
PLACEMENT_RIGHT,
ANCHOR_CORNERpublic static Point2D getPositionRightCenter(Point2D origin, TextLayout text, double angle)
Gets the position in which the text should be drawn according to the provided origin point and angle, placing the text at the right of the point and using the center of the text as anchor.
This method deals with coordinates in 2 different coordinate spaces (the original, non-rotated space and the rotated space). The origin point coordinates has to be referred to the non-rotated space, while the returned position is referred to the rotated space.
origin - The center point of the rotationtext - The text to be drawn, created for the rotated Graphics2Dangle - The rotation angle, in radians. Angle is assumed to be normalized (see
normalizeAngle(double))NoninvertibleTransformExceptionRotatedTextUtils#getPosition(Point2D, double, TextLayout, int, int)},
PLACEMENT_RIGHT,
ANCHOR_CENTERpublic static Point2D getPositionBottomCorner(Point2D origin, TextLayout text, double angle)
Gets the position in which the text should be drawn according to the provided origin point and angle, placing the text at the bottom of the point and using a corner of the text as anchor.
This method deals with coordinates in 2 different coordinate spaces (the original, non-rotated space and the rotated space). The origin point coordinates has to be referred to the non-rotated space, while the returned position is referred to the rotated space.
origin - The center point of the rotationtext - The text to be drawn, created for the rotated Graphics2Dangle - The rotation angle, in radians. Angle is assumed to be normalized (see
normalizeAngle(double))NoninvertibleTransformExceptionRotatedTextUtils#getPosition(Point2D, double, TextLayout, int, int)},
PLACEMENT_BOTTOM,
ANCHOR_CORNERpublic static Point2D getPositionBottomCenter(Point2D origin, TextLayout text, double angle)
Gets the position in which the text should be drawn according to the provided origin point and angle, placing the text at the bottom of the point and using the center of the text as anchor.
This method deals with coordinates in 2 different coordinate spaces (the original, non-rotated space and the rotated space). The origin point coordinates has to be referred to the non-rotated space, while the returned position is referred to the rotated space.
origin - The center point of the rotationtext - The text to be drawn, created for the rotated Graphics2Dangle - The rotation angle, in radians. Angle is assumed to be normalized (see
normalizeAngle(double))NoninvertibleTransformExceptionRotatedTextUtils#getPosition(Point2D, double, TextLayout, int, int)},
PLACEMENT_BOTTOM,
ANCHOR_CENTERpublic static Point2D getPositionLeftCorner(Point2D origin, TextLayout text, double angle)
Gets the position in which the text should be drawn according to the provided origin point and angle, placing the text at the left of the point and using a corner of the text as anchor.
This method deals with coordinates in 2 different coordinate spaces (the original, non-rotated space and the rotated space). The origin point coordinates has to be referred to the non-rotated space, while the returned position is referred to the rotated space.
origin - The center point of the rotationtext - The text to be drawn, created for the rotated Graphics2Dangle - The rotation angle, in radians. Angle is assumed to be normalized (see
normalizeAngle(double))NoninvertibleTransformExceptionRotatedTextUtils#getPosition(Point2D, double, TextLayout, int, int)},
PLACEMENT_LEFT,
ANCHOR_CORNERpublic static Point2D getPositionLeftCenter(Point2D origin, TextLayout text, double angle)
Gets the position in which the text should be drawn according to the provided origin point and angle, placing the text at the left of the point and using the center of the text as anchor.
This method deals with coordinates in 2 different coordinate spaces (the original, non-rotated space and the rotated space). The origin point coordinates has to be referred to the non-rotated space, while the returned position is referred to the rotated space.
origin - The center point of the rotationtext - The text to be drawn, created for the rotated Graphics2Dangle - The rotation angle, in radians. Angle is assumed to be normalized (see
normalizeAngle(double))NoninvertibleTransformExceptionRotatedTextUtils#getPosition(Point2D, double, TextLayout, int, int)},
PLACEMENT_LEFT,
ANCHOR_CENTERpublic static void drawRotated(Point2D location, Graphics2D g, String strText, double angle)
location - The rotation centerg - The Graphics2D on which the text should be drawnstrText - The text to be drawnangle - The rotation angle, in radianspublic static double normalizeAngle(double angle)
angle - The angle to normalize, in radians