void graph2_1::paintEvent(QPaintEvent *)
{
/***********�����α߿���������**************/
QPainter *painter=new QPainter(this);
painter->setRenderHint(QPainter::Antialiasing,true);
painter->drawRect(10,10,380,230);
QPoint beginPoint(50,200);
QPoint xEndPoint(xEndX,xEndY);
QPoint yEndPoint(yEndX,yEndY);
painter->drawLine(beginPoint,xEndPoint);
painter->drawLine(beginPoint,yEndPoint);
//*****************����������ͷ*********/
int xOffset=13;
brush.setColor(Qt::black);
brush.setStyle(Qt::SolidPattern);
painter->setBrush(brush);
QPoint xarrowRightPoint(xEndX+xOffset,xEndY);
QPoint xarrowTopPoint(xEndX,-xOffset*tan(PI/6)+xEndY);
QPoint xarrowBotPoint(xEndX,xOffset*tan(PI/6)+xEndY);
static const QPoint xarrowPoints[3] = {
xarrowRightPoint,xarrowTopPoint,xarrowBotPoint,
};
painter->drawPolygon(xarrowPoints,3);
QPoint yarrowTopPoint(yEndX,yEndY-xOffset);
QPoint yarrowRightPoint(xOffset*tan(PI/6)+yEndX,yEndY);
QPoint yarrowLeftPoint(-xOffset*tan(PI/6)+yEndX,yEndY);
static const QPoint yarrowPoints[3] = {
yarrowTopPoint,yarrowLeftPoint,yarrowRightPoint,
};
painter->drawPolygon(yarrowPoints,3);
painter->setBrush(Qt::NoBrush);
/************��ע������**********/
painter->drawText(xEndX,xEndY+20,tr("HZ"));
//painter->rotate(270);
painter->drawText(yEndY,yEndX+20,tr("dB"));
//painter->rotate(90);
/*************************/
QVector<qreal> dashes;
qreal space = 3;
dashes << 5 << space << 5 << space;
pen.setDashPattern(dashes);
pen.setWidth(2);
pen.setColor(Qt::blue);
painter->setPen(pen);
QPoint point5(90,200);
QPoint point6(100,155);
QPoint point7(250,110);
QPoint point8(300,80);
painter->drawPath(drawBezierCurve(point5,point6));
painter->drawPath(drawBezierCurve(point6,point7));
painter->drawPath(drawBezierCurve(point7,point8));
}
static inline void
line8(Imaging im, int x0, int y0, int x1, int y1, int ink)
{
int i, n, e;
int dx, dy;
int xs, ys;
/* normalize coordinates */
dx = x1-x0;
if (dx < 0)
dx = -dx, xs = -1;
else
xs = 1;
dy = y1-y0;
if (dy < 0)
dy = -dy, ys = -1;
else
ys = 1;
n = (dx > dy) ? dx : dy;
if (dx == 0)
/* vertical */
for (i = 0; i < dy; i++) {
point8(im, x0, y0, ink);
y0 += ys;
}
else if (dy == 0)
/* horizontal */
for (i = 0; i < dx; i++) {
point8(im, x0, y0, ink);
x0 += xs;
}
else if (dx > dy) {
/* bresenham, horizontal slope */
n = dx;
dy += dy;
e = dy - dx;
dx += dx;
for (i = 0; i < n; i++) {
point8(im, x0, y0, ink);
if (e >= 0) {
y0 += ys;
e -= dx;
}
e += dy;
x0 += xs;
}
} else {
/* bresenham, vertical slope */
n = dy;
dx += dx;
e = dx - dy;
dy += dy;
for (i = 0; i < n; i++) {
point8(im, x0, y0, ink);
if (e >= 0) {
x0 += xs;
e -= dy;
}
e += dx;
y0 += ys;
}
}
}