c – 如何使用QOpenGLWidget渲染文本

解决方法

@H_674_7@ 我最终做了一个类似于@jaba写的解决方案.我也注意到一些图形损坏,除非我在方法的结尾调用了painter.end().

void MapCanvas::renderText(double x,double y,double z,const QString &str,const QFont & font = QFont()) {
    // Identify x and y LOCATIOns to render text within widget
    int height = this->height();
    GLdouble textposx = 0,textposy = 0,textPosZ = 0;
    project(x,y,0f,&textposx,&textposy,&textPosz);
    textposy = height - textposy; // y is inverted

    // Retrieve last OpenGL color to use as a font color
    GLdouble glColor[4];
    glGetDoublev(GL_CURRENT_COLOR,glColor);
    QColor fontColor = QColor(glColor[0],glColor[1],glColor[2],glColor[3]);

    // Render text
    QPainter painter(this);
    painter.setPen(fontColor);
    painter.setFont(font);
    painter.drawText(textposx,textposy,text);
    painter.end();
}