qpainter

I'm using QPainter to draw multiline text on QImage. However, I also need to display a colored rectangle around each character's bounding box. So I need to know the bounding box that each character had when being drawn. For example, for painter.drawText(QRect(100, 100, 200, 200), Qt::TextWordWrap, "line\nline2", &r); I would need to get 10 rectangles, taking into account newlines, word-wrap, tabs, etc. For example, the rectangle of the second 'l' would be below the rectangle of the first 'l' , instead of being to the right of 'e' , because of the newline. Something like the coordinates of the

I am using a 3 layer hierarchy of QGLWidgets to share shaders and vertex data between 5 OpenGL viewports in my CAD-like app. The root context is used for compiling application-wide shaders, the per document context is used to share model vertex data, and the viewport contexts are the ones that actually do the rendering (and also contain grid vertex data and other per viewport stuff). The shader sharing seems to work fine, and so does the grid drawing, but when it comes to sharing vertex data it fails and to be honest - I cannot see how it is supposed to work... I built a 3D icon for an item

4.7 and like to overlay two images on a qgraphicsview. The image on top shall be semi-transparent to allow to see through it. Initially both images are fully opaque. I expected some function for setting a global alpha-value for each pixel to exist, but it seems like there is no such function. The closest thing to it is QPixmap::setAlphaChannel(const QPixmap & alphaChannel), which, however, is marked as obsolete since Qt-4.6. Instead the manual refers to the CompositionModes of QPainter, but I don't succeed to add transparency to an opaque image like I want. Could anyone point me to a working

I'm trying to create a Tile rendering program. Heres some basic code. Header class Tile: public QGraphicsItem { public: Tile(void); ~Tile(void); QGraphicsPixmapItem *tileItem; void update(QPainter *painter, const QStyleOptionGraphicsItem *option,QWidget *widget); protected: QRectF boundingRect() const; void paint(QPainter *painter, const QStyleOptionGraphicsItem *option,QWidget *widget); }; CPP: .Constructor etc . . void Tile::paint(QPainter *painter, const QStyleOptionGraphicsItem *option,QWidget *widget) { if(tileItem==NULL) { qDebug()<<"Loading Pixmap"; QPixmap p("c:\\qt\\tile\\tile0-0.png"

I'm working on an application where I need to be able to draw a line between two QWidget objects. I have tried quite a few things, but my current attempt (which I think is in the right direction I just think I'm missing something) is to have the containing widget (which I called DrawWidget and which holds the QGridLayout that the QWidget objects are added to) override the paintEvent method and call the QPainter::drawLine() function. The issues I'm having are that: No matter how I try to get the position of the widgets, the endpoints of the line are always in the wrong place Whenever I try to

I want to paint the background of a slider. I tried this but the color covers up the whole slider. This is in an inherited class of QSlider void paintEvent(QPaintEvent *e) { QPainter painter(this); painter.begin(this); painter.setBrush(/*not important*/); // This covers up the control. How do I make it so the color is in // the background and the control is still visible? painter.drawRect(rect()); painter.end(); } To set the background of a widget you could set the style sheet: theSlider->setStyleSheet("QSlider { background-color: green; }"); The following will set the background of the widget