public class LineTracer extends Object
addVertex
,
followed by a call to flush()
.
Where possible, sub-sequences of the point sequence
are aggregated in supplied work
arrays and plotted using Graphics2D.draw(Shape)
.
This is superior to the more obvious strategy of calling
Graphics.drawLine
for every pair of points.
It is probably faster, it can work with non-integer coordinates,
I think the line joining is better,
and it is necessary to get the dashing right for dashed strokes,
otherwise the dash starts anew for each edge.
However, this is only possible for runs of points of the same colour;
line segments of different colours have to be drawn separately,
which means that lines of varying colour may look worse than
single colour ones (poorer sub-pixel positioning, nastier line joins,
incorrect dash phase).
This class does some other useful things like avoid attempts to plot lines which are extremely long or which are known to be outside the clip.
Constructor and Description |
---|
LineTracer(Graphics g,
Rectangle bounds,
Stroke stroke,
boolean antialias,
int nwork,
boolean isPixel)
Constructor.
|
Modifier and Type | Method and Description |
---|---|
void |
addVertex(double dx,
double dy,
Color color)
Adds a point to the sequence to be plotted.
|
void |
flush()
Ensures that all points have been drawn.
|
public LineTracer(Graphics g, Rectangle bounds, Stroke stroke, boolean antialias, int nwork, boolean isPixel)
nwork
parameter determines the number of points
aggregated into a single plotting call.
There may be visual anomalies every nwork
points, so
it should not be too small, but arrays of this size are allocated,
so it should not be too large either.g
- the base graphics contextbounds
- bounds beyond which lines should not be drawnstroke
- line strokeantialias
- whether lines are to be antialiasednwork
- workspace array sizeisPixel
- if true, the graphics context is considered to be
pixellised, allowing some optimisations to be made
that should not be visiblepublic void addVertex(double dx, double dy, Color color)
color
argument results in a
break in the line.dx
- graphics X coordinatedy
- graphics Y coordinatecolor
- line colour at pointpublic void flush()
addVertex(double, double, java.awt.Color)
calls
to ensure that the drawing has actually been done.Copyright © 2024 Central Laboratory of the Research Councils. All Rights Reserved.