任意拖动曲线¶
qt 画2d图表无非就是QCustomPlot Qwt QCharts。无论是性能、易用、美观都是QCustomPlot最好。
QCustomPlot下载 https://www.qcustomplot.com/index.php/download
QCustomPlot 帮助文档，你下载后文件夹里.qch 结尾的就是帮助文档，添加到 qt creator 里可以直接看
利用 QCustomPlot 增加任意点，并连成直线。
qcpbars_ = new QCPBars(ui->plot->xAxis, ui->plot->yAxis);
qcpbars_->setAntialiased(false);
qcpbars_->setStackingGap(0);
qcpbars_->setPen(QPen(QColor(62, 177, 115)));// 直方图颜色
qcpbars_->setBrush(QColor(62, 177, 115));// 直方图颜色
ui->plot->setBackground(QColor(69, 69, 69));// 图标背景颜色
ui->plot->axisRect()->setBackground(QColor(54, 54, 54));// 图标颜色
ui->plot->setInteraction(QCP::iRangeDrag, false); //鼠标单击拖动
ui->plot->setInteraction(QCP::iRangeZoom, false); //滚轮滑动缩放
ui->plot->addGraph();
ui->plot->graph()->setScatterStyle(
QCPScatterStyle(QCPScatterStyle::ssCircle,
QPen(Qt::black, 1.5), QBrush(Qt::white), 9));
ui->plot->graph()->setLineStyle((QCPGraph::lsLine));
QPen pen;
pen.setWidth(1);
pen.setColor(Qt::white);
ui->plot->graph()->setPen(pen);
ui->plot->xAxis->setSubTicks(0);
ui->plot->yAxis->setSubTicks(0);
ui->plot->xAxis->setLabelColor(QColor(223, 223, 223));
ui->plot->yAxis->setLabelColor(QColor(223, 223, 223));
ui->plot->xAxis->setTickLabelColor(QColor(223, 223, 223));
ui->plot->yAxis->setTickLabelColor(QColor(223, 223, 223));
ui->plot->xAxis->setBasePen(QPen(QColor(223, 223, 223), 1));
ui->plot->yAxis->setBasePen(QPen(QColor(223, 223, 223), 1));
ui->plot->xAxis->setTickPen(QPen(QColor(223, 223, 223), 1));
ui->plot->yAxis->setTickPen(QPen(QColor(223, 223, 223), 1));
ui->plot->xAxis->setSubTickPen(QPen(QColor(223, 223, 223), 1));
ui->plot->yAxis->setSubTickPen(QPen(QColor(223, 223, 223), 1));
ui->plot->xAxis->grid()->setPen(QPen(QColor(88, 88, 90), 0, Qt::DashLine));
ui->plot->yAxis->grid()->setPen(QPen(QColor(88, 88, 90), 0, Qt::DashLine));
void HistogramView::SlotMousePressEvent(QMouseEvent *event) {
int x_pos = event->pos().x();
int y_pos = event->pos().y();
double x_val = ui->plot->xAxis->pixelToCoord(x_pos);
double y_val = ui->plot->yAxis->pixelToCoord(y_pos);
for (int i = 0; i < point_x_.count(); i++) {
if (fabs(x_val - point_x_.at(i)) < 5 && fabs(y_val - point_y_.at(i)) < 5) {
ui->id->setText(QString::number(i));
ui->pos->setText(QString("x:%1 y:%2")
.arg(point_x_[contrast_value_.id])
.arg(point_y_[contrast_value_.id]));
SlotDateUnite(1);
break;
}
}
}
void HistogramView::SlotMouseReleaseEvent(QMouseEvent *event) {
Q_UNUSED(event);
ui->id->setText(QString::number(-1));
ui->pos->setText(QString("x:-1 y:-1"));
SlotDateUnite(1);
}
void HistogramView::SlotMouseMoveEvent(QMouseEvent *event) {
if (contrast_value_.id == -1) {
return;
}
double x_pos = event->pos().x();
double y_pos = event->pos().y();
double x_val = ui->plot->xAxis->pixelToCoord(x_pos);
double y_val = ui->plot->yAxis->pixelToCoord(y_pos);
y_val = QString::number(y_val, 'f', 3).toDouble();
x_val = QString::number(x_val, 'f', 3).toDouble();
// 点逻辑关系
if (contrast_value_.id == 0) {
if (x_val >= point_x_[1]) {
x_val = point_x_[1] - 2;
} else if (x_val <= -20) {
x_val = -20;
}
if (y_val >= point_y_[1]) {
y_val = point_y_[1] - 0.01;
} else if (y_val <= 0) {
y_val = 0.01;
}
} else if (contrast_value_.id == point_x_.count() - 1) {
if (x_val <= point_x_[point_x_.count() - 2]) {
x_val = point_x_[point_x_.count() - 2] + 2;
} else if (x_val >= 300) {
x_val = 300;
}
if (y_val <= point_y_[point_x_.count() - 2]) {
y_val = point_y_[point_x_.count() - 2] + 0.01;
} else if (y_val > 1) {
y_val = 1;
}
} else {
if (x_val <= point_x_[contrast_value_.id - 1]) {
x_val = point_x_[contrast_value_.id - 1] + 2;
}
if (y_val <= point_y_[contrast_value_.id - 1]) {
y_val = point_y_[contrast_value_.id - 1] + 0.01;
}
if (x_val >= point_x_[contrast_value_.id + 1]) {
x_val = point_x_[contrast_value_.id + 1] - 2;
}
if (y_val >= point_y_[contrast_value_.id + 1]) {
y_val = point_y_[contrast_value_.id + 1] - 0.01;
}
}
point_x_[contrast_value_.id] = x_val;
point_y_[contrast_value_.id] = y_val;
ui->pos->setText(QString("x:%1 y:%2")
.arg(point_x_[contrast_value_.id])
.arg(point_y_[contrast_value_.id]));
SlotDateUnite(1);
}
void HistogramView::SlotHistoramReduction() {
historgram_.Execute();
historgram_.GetValWindow(
&contrast_value_.minimum,
&contrast_value_.maximum,
&contrast_value_.level,
&contrast_value_.window);
SlotDateUnite(0);
}
void HistogramView::SlotSpinboxValueChange() {// spinbox change
if (QObject::sender() == ui->level || QObject::sender() == ui->window) {
ui->minimum->setValue(ui->level->value() - (ui->window->value() / 2.0));
ui->maximum->setValue(ui->level->value() + (ui->window->value() / 2.0));
} else if (QObject::sender() == ui->minimum || QObject::sender() == ui->maximum) {
if (ui->minimum->value() >= ui->maximum->value()) {
ui->minimum->setValue(ui->maximum->value() - 255);
}
ui->level->setValue(0.5 * (contrast_value_.minimum + contrast_value_.maximum));
ui->window->setValue(contrast_value_.maximum - contrast_value_.minimum);
}
SlotDateUnite(2);
}
void HistogramView::SlotPosChange() {// pos change
qint32 tmp = point_x_.count();
if (QObject::sender() == ui->add_btn) {
if (tmp < 5) {
tmp++;
}
} else if (QObject::sender() == ui->less_btn) {
if (tmp > 2) {
tmp--;
}
}
point_x_.clear();
point_y_.clear();
point_x_ << contrast_value_.minimum;
point_y_ << 0;
for (qint32 i = 1; i < tmp - 1; ++i) {
point_y_ << (1.0 / (tmp - 1.0))*i;
point_x_ << contrast_value_.minimum + i*(contrast_value_.window / (tmp - 1));
}
point_x_ << contrast_value_.maximum;
point_y_ << 1;
SlotDateUnite(1);
}
void HistogramView::SlotDateUnite(const qint32 change) {
switch (change) {
case 0: {// sturct change
ui->minimum->setValue(contrast_value_.minimum);
ui->maximum->setValue(contrast_value_.maximum);
ui->level->setValue(contrast_value_.level);
ui->window->setValue(contrast_value_.window);
ui->id->setText(QString::number(contrast_value_.id));
ui->pos->setText(contrast_value_.pos);
this->SlotPosChange();
break;
}
case 1: {// pos change
contrast_value_.minimum = point_x_[0];
contrast_value_.maximum = point_x_[point_x_.count() - 1];
contrast_value_.level =
0.5 * (contrast_value_.minimum + contrast_value_.maximum);
contrast_value_.window =
contrast_value_.maximum - contrast_value_.minimum;
contrast_value_.id = ui->id->text().toInt();
contrast_value_.pos = ui->pos->text();
ui->minimum->setValue(contrast_value_.minimum);
ui->maximum->setValue(contrast_value_.maximum);
ui->level->setValue(contrast_value_.level);
ui->window->setValue(contrast_value_.window);
ui->id->setText(QString::number(contrast_value_.id));
ui->pos->setText(contrast_value_.pos);
break;
}
case 2: {// spinbox change
contrast_value_.minimum = ui->minimum->value();
contrast_value_.maximum = ui->maximum->value();
contrast_value_.level = ui->level->value();
contrast_value_.window = ui->window->value();
contrast_value_.id = ui->id->text().toInt();
contrast_value_.pos = ui->pos->text();
this->SlotPosChange();
break;
}
default:
break;
}
HistogramExecute();
historgram_.CalcOrgImgHistData(51);
QVector<double> ticks;
for (int i = 0; i < 51; ++i) {
ticks << contrast_value_.minimum + (i * contrast_value_.window / 50);
}
qcpbars_->setData(ticks, historgram_.GetHistogramData());
ui->plot->graph()->setData(point_x_, point_y_);
ui->plot->xAxis->setRange(
contrast_value_.minimum - 10, contrast_value_.maximum + 10);
ui->plot->yAxis->setRange(-0.2, 1.2);
ui->plot->replot();
}