QDebug operator<<(QDebug dbg, const QDoubleVector3D &vector)
{
QDebugStateSaver saver(dbg);
dbg.nospace() << "QDoubleVector3D("
<< vector.x() << ", " << vector.y() << ", " << vector.z() << ')';
return dbg;
}
double QDoubleVector3D::distanceToLine
(const QDoubleVector3D &point, const QDoubleVector3D &direction) const
{
if (direction.isNull())
return (*this - point).length();
QDoubleVector3D p = point + dotProduct(*this - point, direction) * direction;
return (*this - p).length();
}
void QGeoCameraTilesPrivate::appendZIntersects(const QDoubleVector3D &start,
const QDoubleVector3D &end,
double z,
QVector<QDoubleVector3D> &results) const
{
if (start.z() == end.z()) {
if (start.z() == z) {
results.append(start);
results.append(end);
}
} else {
double f = (start.z() - z) / (start.z() - end.z());
if ((0 <= f) && (f <= 1.0)) {
results.append((1 - f) * start + f * end);
}
}
}
QPair<Polygon, Polygon> QGeoCameraTilesPrivate::clipFootprintToMap(const Polygon &footprint) const
{
bool clipX0 = false;
bool clipX1 = false;
bool clipY0 = false;
bool clipY1 = false;
double side = 1.0 * sideLength_;
typedef Polygon::const_iterator const_iter;
const_iter i = footprint.constBegin();
const_iter end = footprint.constEnd();
for (; i != end; ++i) {
QDoubleVector3D p = *i;
if ((p.x() < 0.0) || (qFuzzyIsNull(p.x())))
clipX0 = true;
if ((side < p.x()) || (qFuzzyCompare(side, p.x())))
clipX1 = true;
if (p.y() < 0.0)
clipY0 = true;
if (side < p.y())
clipY1 = true;
}
Polygon results = footprint;
if (clipY0) {
results = splitPolygonAtAxisValue(results, 1, 0.0).second;
}
if (clipY1) {
results = splitPolygonAtAxisValue(results, 1, side).first;
}
if (clipX0) {
if (clipX1) {
results = splitPolygonAtAxisValue(results, 0, 0.0).second;
results = splitPolygonAtAxisValue(results, 0, side).first;
return QPair<Polygon, Polygon>(results, Polygon());
} else {
QPair<Polygon, Polygon> pair = splitPolygonAtAxisValue(results, 0, 0.0);
if (pair.first.isEmpty()) {
// if we touched the line but didn't cross it...
for (int i = 0; i < pair.second.size(); ++i) {
if (qFuzzyIsNull(pair.second.at(i).x()))
pair.first.append(pair.second.at(i));
}
if (pair.first.size() == 2) {
double y0 = pair.first[0].y();
double y1 = pair.first[1].y();
pair.first.clear();
pair.first.append(QDoubleVector3D(side, y0, 0.0));
pair.first.append(QDoubleVector3D(side - 0.001, y0, 0.0));
pair.first.append(QDoubleVector3D(side - 0.001, y1, 0.0));
pair.first.append(QDoubleVector3D(side, y1, 0.0));
} else if (pair.first.size() == 1) {
// FIXME this is trickier
// - touching at one point on the tile boundary
// - probably need to build a triangular polygon across the edge
// - don't want to add another y tile if we can help it
// - initial version doesn't care
double y = pair.first.at(0).y();
pair.first.clear();
pair.first.append(QDoubleVector3D(side - 0.001, y, 0.0));
pair.first.append(QDoubleVector3D(side, y + 0.001, 0.0));
pair.first.append(QDoubleVector3D(side, y - 0.001, 0.0));
}
} else {
for (int i = 0; i < pair.first.size(); ++i) {
pair.first[i].setX(pair.first.at(i).x() + side);
}
}
return pair;
}
} else {
if (clipX1) {
QPair<Polygon, Polygon> pair = splitPolygonAtAxisValue(results, 0, side);
if (pair.second.isEmpty()) {
// if we touched the line but didn't cross it...
for (int i = 0; i < pair.first.size(); ++i) {
if (qFuzzyCompare(side, pair.first.at(i).x()))
pair.second.append(pair.first.at(i));
}
if (pair.second.size() == 2) {
double y0 = pair.second[0].y();
double y1 = pair.second[1].y();
pair.second.clear();
pair.second.append(QDoubleVector3D(0, y0, 0.0));
pair.second.append(QDoubleVector3D(0.001, y0, 0.0));
pair.second.append(QDoubleVector3D(0.001, y1, 0.0));
pair.second.append(QDoubleVector3D(0, y1, 0.0));
} else if (pair.second.size() == 1) {
// FIXME this is trickier
// - touching at one point on the tile boundary
// - probably need to build a triangular polygon across the edge
// - don't want to add another y tile if we can help it
// - initial version doesn't care
double y = pair.second.at(0).y();
pair.second.clear();
pair.second.append(QDoubleVector3D(0.001, y, 0.0));
pair.second.append(QDoubleVector3D(0.0, y - 0.001, 0.0));
pair.second.append(QDoubleVector3D(0.0, y + 0.001, 0.0));
}
} else {
for (int i = 0; i < pair.second.size(); ++i) {
pair.second[i].setX(pair.second.at(i).x() - side);
}
}
return pair;
} else {
return QPair<Polygon, Polygon>(results, Polygon());
}
}
}
// Returns the intersection of the plane of the map and the camera frustum as a right handed polygon
Polygon QGeoCameraTilesPrivate::frustumFootprint(const Frustum &frustum) const
{
Polygon points;
points.reserve(24);
appendZIntersects(frustum.topLeftNear, frustum.topLeftFar, 0.0, points);
appendZIntersects(frustum.topRightNear, frustum.topRightFar, 0.0, points);
appendZIntersects(frustum.bottomLeftNear, frustum.bottomLeftFar, 0.0, points);
appendZIntersects(frustum.bottomRightNear, frustum.bottomRightFar, 0.0, points);
appendZIntersects(frustum.topLeftNear, frustum.bottomLeftNear, 0.0, points);
appendZIntersects(frustum.bottomLeftNear, frustum.bottomRightNear, 0.0, points);
appendZIntersects(frustum.bottomRightNear, frustum.topRightNear, 0.0, points);
appendZIntersects(frustum.topRightNear, frustum.topLeftNear, 0.0, points);
appendZIntersects(frustum.topLeftFar, frustum.bottomLeftFar, 0.0, points);
appendZIntersects(frustum.bottomLeftFar, frustum.bottomRightFar, 0.0, points);
appendZIntersects(frustum.bottomRightFar, frustum.topRightFar, 0.0, points);
appendZIntersects(frustum.topRightFar, frustum.topLeftFar, 0.0, points);
if (points.isEmpty())
return points;
// sort points into a right handed polygon
LengthSorter sorter;
// - initial sort to remove duplicates
sorter.base = points.first();
qSort(points.begin(), points.end(), sorter);
for (int i = points.size() - 1; i > 0; --i) {
if (points.at(i) == points.at(i - 1))
points.remove(i);
}
// - proper sort
// - start with the first point, put it in the sorted part of the list
// - add the nearest unsorted point to the last sorted point to the end
// of the sorted points
Polygon::iterator i;
for (i = points.begin(); i != points.end(); ++i) {
sorter.base = *i;
if (i + 1 != points.end())
qSort(i + 1, points.end(), sorter);
}
// - determine if what we have is right handed
int size = points.size();
if (size >= 3) {
QDoubleVector3D normal = QDoubleVector3D::normal(points.at(1) - points.at(0),
points.at(2) - points.at(1));
// - if not, reverse the list
if (normal.z() < 0.0) {
int halfSize = size / 2;
for (int i = 0; i < halfSize; ++i) {
QDoubleVector3D spare = points.at(i);
points[i] = points[size - 1 - i];
points[size - 1 - i] = spare;
}
}
}
return points;
}
Frustum QGeoCameraTilesPrivate::frustum(double fieldOfViewGradient) const
{
QDoubleVector3D center = sideLength_ * QGeoProjection::coordToMercator(camera_.center());
center.setZ(0.0);
double f = qMin(screenSize_.width(), screenSize_.height()) / (1.0 * tileSize_);
double z = std::pow(2.0, camera_.zoomLevel() - intZoomLevel_);
double altitude = f / (2.0 * z);
QDoubleVector3D eye = center;
eye.setZ(altitude);
QDoubleVector3D view = eye - center;
QDoubleVector3D side = QDoubleVector3D::normal(view, QDoubleVector3D(0.0, 1.0, 0.0));
QDoubleVector3D up = QDoubleVector3D::normal(side, view);
double nearPlane = sideLength_ / (1.0 * tileSize_ * (1 << maxZoom_));
double farPlane = 3.0;
double aspectRatio = 1.0 * screenSize_.width() / screenSize_.height();
double hn = 0.0;
double wn = 0.0;
double hf = 0.0;
double wf = 0.0;
// fixes field of view at 45 degrees
// this assumes that viewSize = 2*nearPlane x 2*nearPlane
if (aspectRatio > 1.0) {
hn = 2 * fieldOfViewGradient * nearPlane;
wn = hn * aspectRatio;
hf = 2 * fieldOfViewGradient * farPlane;
wf = hf * aspectRatio;
} else {
wn = 2 * fieldOfViewGradient * nearPlane;
hn = wn / aspectRatio;
wf = 2 * fieldOfViewGradient * farPlane;
hf = wf / aspectRatio;
}
QDoubleVector3D d = center - eye;
d.normalize();
up.normalize();
QDoubleVector3D right = QDoubleVector3D::normal(d, up);
QDoubleVector3D cf = eye + d * farPlane;
QDoubleVector3D cn = eye + d * nearPlane;
Frustum frustum;
frustum.topLeftFar = cf + (up * hf / 2) - (right * wf / 2);
frustum.topRightFar = cf + (up * hf / 2) + (right * wf / 2);
frustum.bottomLeftFar = cf - (up * hf / 2) - (right * wf / 2);
frustum.bottomRightFar = cf - (up * hf / 2) + (right * wf / 2);
frustum.topLeftNear = cn + (up * hn / 2) - (right * wn / 2);
frustum.topRightNear = cn + (up * hn / 2) + (right * wn / 2);
frustum.bottomLeftNear = cn - (up * hn / 2) - (right * wn / 2);
frustum.bottomRightNear = cn - (up * hn / 2) + (right * wn / 2);
return frustum;
}
