/** Updates the visibility of tick labels. */
private void updateTickVisibility() {
// initialize the array of tick label visibility state
tickVisibilities.clear();
for (int i = 0; i < tickLabelPositions.size(); i++) {
tickVisibilities.add(Boolean.TRUE);
}
if (tickLabelPositions.size() == 0 || axis.getTick().getTickLabelAngle() != 0) {
return;
}
// set the tick label visibility
int previousPosition = 0;
for (int i = 0; i < tickLabelPositions.size(); i++) {
// check if there is enough space to draw tick label
boolean hasSpaceToDraw = true;
if (i != 0) {
hasSpaceToDraw =
hasSpaceToDraw(previousPosition, tickLabelPositions.get(i), tickLabels.get(i));
}
// check if the tick label value is major
boolean isMajorTick = true;
if (!axis.isValidCategoryAxis()) {
if (axis.isLogScaleEnabled()) {
isMajorTick = isMajorTick(tickLabelValues.get(i));
}
// check if the same tick label is repeated
String currentLabel = tickLabels.get(i);
try {
double value = Double.parseDouble(currentLabel);
if (value != tickLabelValues.get(i)) {
isMajorTick = false;
}
} catch (NumberFormatException e) {
// label is not decimal value but string
}
}
if (hasSpaceToDraw && isMajorTick) {
previousPosition = tickLabelPositions.get(i);
} else {
tickVisibilities.set(i, Boolean.FALSE);
}
}
}
/**
* Updates the tick labels.
*
* @param length the axis length
*/
protected void update(int length) {
tickLabelValues.clear();
tickLabels.clear();
tickLabelPositions.clear();
if (axis.isValidCategoryAxis()) {
updateTickLabelForCategoryAxis(length);
} else if (axis.isLogScaleEnabled()) {
updateTickLabelForLogScale(length);
} else if (axis.isDateEnabled()) {
updateTickLabelForDateAxis(length);
} else {
updateTickLabelForLinearScale(length);
}
updateTickVisibility();
updateTickLabelMaxLength();
}
/**
* Draw the X tick.
*
* @param gc the graphics context
*/
private void drawXTick(GC gc) {
int offset = axis.getTick().getAxisTickMarks().getBounds().x;
// draw tick labels
gc.setFont(axis.getTick().getFont());
int angle = axis.getTick().getTickLabelAngle();
for (int i = 0; i < tickLabelPositions.size(); i++) {
if (axis.isValidCategoryAxis() || tickVisibilities.get(i) == true) {
String text = tickLabels.get(i);
int textWidth = gc.textExtent(text).x;
int textHeight = gc.textExtent(text).y;
if (angle == 0) {
int x = (int) (tickLabelPositions.get(i) - textWidth / 2d + offset);
gc.drawText(text, bounds.x + x, bounds.y);
continue;
}
float x, y;
if (axis.getPosition() == Position.Primary) {
x =
(float)
(offset
+ bounds.x
+ tickLabelPositions.get(i)
- textWidth * Math.cos(Math.toRadians(angle))
- textHeight / 2d * Math.sin(Math.toRadians(angle)));
y = (float) (bounds.y + textWidth * Math.sin(Math.toRadians(angle)));
} else {
x =
(float)
(offset
+ bounds.x
+ tickLabelPositions.get(i)
- textHeight / 2d * Math.sin(Math.toRadians(angle)));
y = (float) (bounds.y + tickLabelMaxLength * Math.sin(Math.toRadians(angle)));
}
drawRotatedText(gc, text, x, y, angle);
}
}
}