public static void drawArrow(Graphics g, int x1, int y1, int x2, int y2, int lineWidth) {
// Draw line using user defined drawline() which can specify line width
drawLine(g, x1, y1, x2, y2, lineWidth);
// Calculate x-y values for arrow head
calcValues(x1, y1, x2, y2);
g.fillPolygon(xValues, yValues, 3);
}
public static void drawLine(Graphics g, int x1, int y1, int x2, int y2, int lineWidth) {
if (lineWidth == 1) g.drawLine(x1, y1, x2, y2);
else {
double angle;
double halfWidth = ((double) lineWidth) / 2.0;
double deltaX = (double) (x2 - x1);
double deltaY = (double) (y2 - y1);
if (x1 == x2) angle = Math.PI;
else angle = Math.atan(deltaY / deltaX) + Math.PI / 2;
int xOffset = (int) (halfWidth * Math.cos(angle));
int yOffset = (int) (halfWidth * Math.sin(angle));
int[] xCorners = {x1 - xOffset, x2 - xOffset + 1, x2 + xOffset + 1, x1 + xOffset};
int[] yCorners = {y1 - yOffset, y2 - yOffset, y2 + yOffset + 1, y1 + yOffset + 1};
g.fillPolygon(xCorners, yCorners, 4);
}
}