Game Programming using Qt 5 Beginner's Guide - Second Edition

Time for action – Adding path items to the scene

Let's paint a few objects consisting of a large number of lines:

static const int SIZE = 100;
static const int MARGIN = 10;
static const int FIGURE_COUNT = 5;
static const int LINE_COUNT = 500;
for(int figureNum = 0; figureNum < FIGURE_COUNT; ++figureNum) {
    QPainterPath path;
    path.moveTo(0, 0);
    for(int i = 0; i < LINE_COUNT; ++i) {
        path.lineTo(qrand() % SIZE, qrand() % SIZE);
    }
    QGraphicsPathItem *item = scene.addPath(path);
    item->setPos(figureNum * (SIZE + MARGIN), 0);
}

For each item, we first create a QPainterPath and set the current position to (0, 0). Then, we use the qrand() function to generate random numbers, apply the modulus operator (%) to produce a number from 0 to SIZE (excluding ...