diff options
Diffstat (limited to 'src/boost/tools/build/example/qt/qt4/hello/arrow.cpp')
-rw-r--r-- | src/boost/tools/build/example/qt/qt4/hello/arrow.cpp | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/src/boost/tools/build/example/qt/qt4/hello/arrow.cpp b/src/boost/tools/build/example/qt/qt4/hello/arrow.cpp new file mode 100644 index 000000000..5f36ed5a8 --- /dev/null +++ b/src/boost/tools/build/example/qt/qt4/hello/arrow.cpp @@ -0,0 +1,158 @@ +// Copyright Vladimir Prus 2005. +// Distributed under the Boost Software License, Version 1.0. +// (See accompanying file LICENSE.txt +// or copy at https://www.bfgroup.xyz/b2/LICENSE.txt) + +#include "arrow.h" + +#include <QtGui/qapplication.h> + +#include <QtGui/qwidget.h> +#include <QtGui/qpainter.h> +#include <QtGui/qpainterpath.h> + +#include <stdlib.h> +#include <math.h> + +Arrow_widget::Arrow_widget(QWidget* parent) : QWidget(parent), color_(0) +{ + QPalette pal = palette(); + pal.setBrush(backgroundRole(), QBrush(Qt::white)); + setPalette(pal); +} + +void Arrow_widget::slotChangeColor() +{ + color_ = (color_ + 1) % 3; + update(); +} + +void +Arrow_widget::draw_arrow(int x1, int y1, int x2, int y2, QPainter& painter) +{ + // The length of the from the tip of the arrow to the point + // where line starts. + const int arrowhead_length = 16; + + QPainterPath arrow; + arrow.moveTo(x1, y1); + + // Determine the angle of the straight line. + double a1 = (x2-x1); + double a2 = (y2-y1); + double b1 = 1; + double b2 = 0; + + double straight_length = sqrt(a1*a1 + a2*a2); + + double dot_product = a1*b1 + a2*b2; + double cosine = dot_product/ + (sqrt(pow(a1, 2) + pow(a2, 2))*sqrt(b1 + b2)); + double angle = acos(cosine); + if (y1 < y2) + { + angle = -angle; + } + double straight_angle = angle*180/M_PI; + + double limit = 10; + + double angle_to_vertical; + if (fabs(straight_angle) < 90) + angle_to_vertical = fabs(straight_angle); + else if (straight_angle > 0) + angle_to_vertical = 180-straight_angle; + else + angle_to_vertical = 180-(-straight_angle); + + double angle_delta = 0; + if (angle_to_vertical > limit) + angle_delta = 30 * (angle_to_vertical - limit)/90; + double start_angle = straight_angle > 0 + ? straight_angle - angle_delta : + straight_angle + angle_delta; + + + QMatrix m1; + m1.translate(x1, y1); + m1.rotate(-start_angle); + + double end_angle = straight_angle > 0 + ? (straight_angle + 180 + angle_delta) : + (straight_angle + 180 - angle_delta); + + QMatrix m2; + m2.reset(); + m2.translate(x2, y2); + m2.rotate(-end_angle); + + arrow.cubicTo(m1.map(QPointF(straight_length/2, 0)), + m2.map(QPointF(straight_length/2, 0)), + m2.map(QPointF(arrowhead_length, 0))); + + painter.save(); + painter.setBrush(Qt::NoBrush); + painter.drawPath(arrow); + painter.restore(); + + painter.save(); + painter.translate(x2, y2); + + painter.rotate(-90); + painter.rotate(-end_angle); + painter.rotate(180); + + QPolygon arrowhead(4); + arrowhead.setPoint(0, 0, 0); + arrowhead.setPoint(1, arrowhead_length/3, -arrowhead_length*5/4); + arrowhead.setPoint(2, 0, -arrowhead_length); + arrowhead.setPoint(3, -arrowhead_length/3, -arrowhead_length*5/4); + + painter.drawPolygon(arrowhead); + + painter.restore(); + +} + + +void Arrow_widget::paintEvent(QPaintEvent*) +{ + QPainter p(this); + + p.setRenderHint(QPainter::Antialiasing); + + int base_x = 550; + int base_y = 200; + + if (color_ == 0) + p.setBrush(Qt::black); + else if (color_ == 1) + p.setBrush(Qt::green); + else if (color_ == 2) + p.setBrush(Qt::yellow); + else + p.setBrush(Qt::black); + + for (int x_step = 0; x_step < 6; ++x_step) + { + for (int y_step = 1; y_step <= 3; ++y_step) + { + draw_arrow(base_x, base_y, base_x+x_step*100, + base_y - y_step*50, p); + + draw_arrow(base_x, base_y, base_x+x_step*100, + base_y + y_step*50, p); + + draw_arrow(base_x, base_y, base_x-x_step*100, + base_y + y_step*50, p); + + draw_arrow(base_x, base_y, base_x-x_step*100, + base_y - y_step*50, p); + } + } + + draw_arrow(50, 400, 1000, 450, p); + draw_arrow(1000, 400, 50, 450, p); + +} + |