// Zoom in and out according to the change in wheel delta.
void QGLView::wheel(int delta)
{
if (d->options & QGLView::FOVZoom) {
//Use field-of view as zoom (much like a traditional camera)
qreal scale = qAbs(viewDelta(delta, delta).x());
if (delta < 0)
scale = -scale;
if (scale >= 0.0f)
scale += 1.0f;
else
scale = 1.0f / (1.0f - scale);
qreal fov = d->camera->fieldOfView();
if (fov != 0.0f)
d->camera->setFieldOfView(d->camera->fieldOfView() / scale);
else
d->camera->setViewSize(d->camera->viewSize() / scale);
} else {
// enable this to get wheel navigation that actually zooms by moving the
// camera back, as opposed to making the angle of view wider.
QVector3D viewVector= camera()->eye() - camera()->center();
qreal zoomMag = viewVector.length();
qreal zoomIncrement = -float(delta) / 100.0f;
if (!qFuzzyIsNull(zoomIncrement))
{
zoomMag += zoomIncrement;
if (zoomMag < 1.0f)
zoomMag = 1.0f;
QRay3D viewLine(camera()->center(), viewVector.normalized());
camera()->setEye(viewLine.point(zoomMag));
}
}
}
// Pan left/right/up/down without rotating about the object.
void QGLView::pan(int deltax, int deltay)
{
QPointF delta = viewDelta(deltax, deltay);
QVector3D t = d->camera->translation(delta.x(), -delta.y(), 0.0f);
// Technically panning the eye left should make the object appear to
// move off to the right, but this looks weird on-screen where the user
// actually thinks they are picking up the object and dragging it rather
// than moving the eye. We therefore apply the inverse of the translation
// to make it "look right".
d->camera->setEye(d->camera->eye() - t);
d->camera->setCenter(d->camera->center() - t);
}
// Pan left/right/up/down without rotating about the object.
void QGLGraphicsNavigationItemPrivate::pan(qreal deltax, qreal deltay)
{
QGLCamera *camera = viewportItem->camera();
QPointF delta = viewDelta(deltax, deltay);
QVector3D t = camera->translation(delta.x(), -delta.y(), 0.0f);
// Technically panning the eye left should make the object appear to
// move off to the right, but this looks weird on-screen where the user
// actually thinks they are picking up the object and dragging it rather
// than moving the eye. We therefore apply the inverse of the translation
// to make it "look right".
camera->setEye(camera->eye() - t);
camera->setCenter(camera->center() - t);
}
// Zoom in and out according to the change in wheel delta.
void QGLView::wheel(int delta)
{
qreal scale = qAbs(viewDelta(delta, delta).x());
if (delta < 0)
scale = -scale;
if (scale >= 0.0f)
scale += 1.0f;
else
scale = 1.0f / (1.0f - scale);
qreal fov = d->camera->fieldOfView();
if (fov != 0.0f)
d->camera->setFieldOfView(d->camera->fieldOfView() / scale);
else
d->camera->setViewSize(d->camera->viewSize() / scale);
}
// Zoom in and out according to the change in wheel delta.
void QGLGraphicsNavigationItemPrivate::wheel(qreal delta)
{
QGLCamera *camera = viewportItem->camera();
qreal scale = qAbs(viewDelta(delta, delta).x());
if (delta < 0)
scale = -scale;
if (scale >= 0.0f)
scale += 1.0f;
else
scale = 1.0f / (1.0f - scale);
qreal fov = camera->fieldOfView();
if (fov != 0.0f)
camera->setFieldOfView(camera->fieldOfView() / scale);
else
camera->setViewSize(camera->viewSize() / scale);
}