diff options
Diffstat (limited to 'src/location/maps/qgeoprojection.cpp')
| -rw-r--r-- | src/location/maps/qgeoprojection.cpp | 237 |
1 files changed, 205 insertions, 32 deletions
diff --git a/src/location/maps/qgeoprojection.cpp b/src/location/maps/qgeoprojection.cpp index a54eee54..77a91a15 100644 --- a/src/location/maps/qgeoprojection.cpp +++ b/src/location/maps/qgeoprojection.cpp @@ -37,12 +37,23 @@ #include "qgeoprojection_p.h" #include <QtPositioning/private/qwebmercator_p.h> #include <QtPositioning/private/qlocationutils_p.h> +#include <QtPositioning/private/qclipperutils_p.h> #include <QSize> #include <cmath> -QT_BEGIN_NAMESPACE +namespace { + static const double defaultTileSize = 256.0; + static const QDoubleVector3D xyNormal(0.0, 0.0, 1.0); + static const QDoubleVector3D xyPoint(0.0, 0.0, 0.0); + static const QGeoProjectionWebMercator::Plane xyPlane(QDoubleVector3D(0,0,0), QDoubleVector3D(0,0,1)); + static const QList<QDoubleVector2D> mercatorGeometry = { + QDoubleVector2D(-1.0,0.0), + QDoubleVector2D( 2.0,0.0), + QDoubleVector2D( 2.0,1.0), + QDoubleVector2D(-1.0,1.0) }; +} -static const double defaultTileSize = 256.0; +QT_BEGIN_NAMESPACE QGeoProjection::QGeoProjection() { @@ -58,7 +69,6 @@ QGeoProjection::~QGeoProjection() * QGeoProjectionWebMercator implementation */ - QGeoProjectionWebMercator::QGeoProjectionWebMercator() : QGeoProjection(), m_mapEdgeSize(256), // at zl 0 @@ -74,10 +84,8 @@ QGeoProjectionWebMercator::QGeoProjectionWebMercator() m_nearPlane(0.0), m_farPlane(0.0), m_halfWidth(0.0), - m_halfHeight(0.0), - m_plane(QDoubleVector3D(0,0,0), QDoubleVector3D(0,0,1)) + m_halfHeight(0.0) { - } QGeoProjectionWebMercator::~QGeoProjectionWebMercator() @@ -190,16 +198,8 @@ QDoubleVector2D QGeoProjectionWebMercator::itemPositionToWrappedMapProjection(co pos *= QDoubleVector2D(m_1_viewportWidth, m_1_viewportHeight); pos *= 2.0; pos -= QDoubleVector2D(1.0,1.0); - pos *= QDoubleVector2D(m_halfWidth, m_halfHeight); - - QDoubleVector3D p = m_centerNearPlane; - p -= m_up * pos.y(); - p -= m_side * pos.x(); - QDoubleVector3D ray = p - m_eye; - ray.normalize(); - - return (m_plane.lineIntersection(m_eye, ray) / m_sideLength).toVector2D(); + return viewportToWrappedMapProjection(pos); } /* Default implementations */ @@ -235,32 +235,67 @@ QDoubleVector2D QGeoProjectionWebMercator::coordinateToItemPosition(const QGeoCo return pos; } +QDoubleVector2D QGeoProjectionWebMercator::geoToWrappedMapProjection(const QGeoCoordinate &coordinate) const +{ + return wrapMapProjection(geoToMapProjection(coordinate)); +} + +QGeoCoordinate QGeoProjectionWebMercator::wrappedMapProjectionToGeo(const QDoubleVector2D &wrappedProjection) const +{ + return mapProjectionToGeo(unwrapMapProjection(wrappedProjection)); +} + bool QGeoProjectionWebMercator::isProjectable(const QDoubleVector2D &wrappedProjection) const { - QDoubleVector3D pos = wrappedProjection * m_sideLength; + if (m_cameraData.tilt() == 0.0) + return true; - // TODO: add an offset to the eye - QDoubleVector3D p = m_eye - pos; + QDoubleVector3D pos = wrappedProjection * m_sideLength; + // use m_centerNearPlane in order to add an offset to m_eye. + QDoubleVector3D p = m_centerNearPlane - pos; double dot = QDoubleVector3D::dotProduct(p , m_viewNormalized); - if (dot < 0.0) // behind the eye + if (dot < 0.0) // behind the near plane return false; return true; } +QList<QDoubleVector2D> QGeoProjectionWebMercator::visibleRegion() const +{ + return m_visibleRegion; +} + +QDoubleVector2D QGeoProjectionWebMercator::viewportToWrappedMapProjection(const QDoubleVector2D &itemPosition) const +{ + QDoubleVector2D pos = itemPosition; + pos *= QDoubleVector2D(m_halfWidth, m_halfHeight); + + QDoubleVector3D p = m_centerNearPlane; + p -= m_up * pos.y(); + p -= m_side * pos.x(); + + QDoubleVector3D ray = p - m_eye; + ray.normalize(); + + return (xyPlane.lineIntersection(m_eye, ray) / m_sideLength).toVector2D(); +} + void QGeoProjectionWebMercator::setupCamera() { - QDoubleVector2D camCenterMercator = geoToMapProjection(m_cameraData.center()); - m_cameraCenterXMercator = camCenterMercator.x(); - m_cameraCenterYMercator = camCenterMercator.y(); + m_centerMercator = geoToMapProjection(m_cameraData.center()); + m_cameraCenterXMercator = m_centerMercator.x(); + m_cameraCenterYMercator = m_centerMercator.y(); int intZoomLevel = static_cast<int>(std::floor(m_cameraData.zoomLevel())); m_sideLength = (1 << intZoomLevel) * defaultTileSize; - m_center = camCenterMercator * m_sideLength; + m_center = m_centerMercator * m_sideLength; double f = 1.0 * qMin(m_viewportWidth, m_viewportHeight); double z = std::pow(2.0, m_cameraData.zoomLevel() - intZoomLevel) * defaultTileSize; - double altitude = f / (2.0 * z) ; + double altitude = f / (2.0 * z); + // Also in mercator space + double z_mercator = std::pow(2.0, m_cameraData.zoomLevel()) * defaultTileSize; + double altitude_mercator = f / (2.0 * z_mercator); //aperture(90 / 2) = 1 m_aperture = tan(QLocationUtils::radians(m_cameraData.fieldOfView()) * 0.5); @@ -268,44 +303,76 @@ void QGeoProjectionWebMercator::setupCamera() m_eye = m_center; m_eye.setZ(altitude * defaultTileSize / m_aperture); + // And in mercator space + m_eyeMercator = m_centerMercator; + m_eyeMercator.setZ(altitude_mercator); + m_view = m_eye - m_center; QDoubleVector3D side = QDoubleVector3D::normal(m_view, QDoubleVector3D(0.0, 1.0, 0.0)); m_up = QDoubleVector3D::normal(side, m_view); + // In mercator space too + m_viewMercator = m_eyeMercator - m_centerMercator; + QDoubleVector3D sideMercator = QDoubleVector3D::normal(m_viewMercator, QDoubleVector3D(0.0, 1.0, 0.0)); + m_upMercator = QDoubleVector3D::normal(sideMercator, m_viewMercator); + if (m_cameraData.bearing() > 0.0) { - // old bearing, tilt and roll code QDoubleMatrix4x4 mBearing; mBearing.rotate(m_cameraData.bearing(), m_view); m_up = mBearing * m_up; + + // In mercator space too + QDoubleMatrix4x4 mBearingMercator; + mBearingMercator.rotate(m_cameraData.bearing(), m_viewMercator); + m_upMercator = mBearingMercator * m_upMercator; } m_side = QDoubleVector3D::normal(m_up, m_view); + m_sideMercator = QDoubleVector3D::normal(m_upMercator, m_viewMercator); - if (m_cameraData.tilt() > 0.0) { + if (m_cameraData.tilt() > 0.0) { // tilt has been already thresholded by QGeoCameraData::setTilt QDoubleMatrix4x4 mTilt; mTilt.rotate(-m_cameraData.tilt(), m_side); m_eye = mTilt * m_view + m_center; + + // In mercator space too + QDoubleMatrix4x4 mTiltMercator; + mTiltMercator.rotate(-m_cameraData.tilt(), m_sideMercator); + m_eyeMercator = mTiltMercator * m_viewMercator + m_centerMercator; } m_view = m_eye - m_center; m_viewNormalized = m_view.normalized(); m_up = QDoubleVector3D::normal(m_view, m_side); - m_nearPlane = 1; - // 10000.0 to make sure that everything fits in the frustum even at high zoom levels - // (that is, with a very large map) - // TODO: extend this to support clip distance - m_farPlane = (altitude + 10000.0) * defaultTileSize; + m_nearPlane = 1.0; + // At ZL 20 the map has 2^20 tiles per side. That is 1048576. + // Placing the camera on one corner of the map, rotated toward the opposite corner, and tilted + // at almost 90 degrees would require a frustum that can span the whole size of this map. + // For this reason, the far plane is set to 2 * 2^20 * defaultTileSize. + // That is, in order to make sure that the whole map would fit in the frustum at this ZL. + // Since we are using a double matrix, and since the largest value in the matrix is going to be + // 2 * m_farPlane (as near plane is 1.0), there should be sufficient precision left. + // + // TODO: extend this to support clip distance. + m_farPlane = (altitude + 2097152.0) * defaultTileSize; + + m_viewMercator = m_eyeMercator - m_centerMercator; + m_upMercator = QDoubleVector3D::normal(m_viewMercator, m_sideMercator); + m_nearPlaneMercator = 1.0 / m_sideLength; double aspectRatio = 1.0 * m_viewportWidth / m_viewportHeight; m_halfWidth = m_aperture; m_halfHeight = m_aperture; + double verticalAperture = m_aperture; if (aspectRatio > 1.0) { m_halfWidth *= aspectRatio; } else if (aspectRatio > 0.0 && aspectRatio < 1.0) { m_halfHeight /= aspectRatio; + verticalAperture /= aspectRatio; } + double verticalHalfFOV = QLocationUtils::degrees(atan(verticalAperture)); QDoubleMatrix4x4 cameraMatrix; cameraMatrix.lookAt(m_eye, m_center, m_up); @@ -314,7 +381,113 @@ void QGeoProjectionWebMercator::setupCamera() projectionMatrix.frustum(-m_halfWidth, m_halfWidth, -m_halfHeight, m_halfHeight, m_nearPlane, m_farPlane); m_transformation = projectionMatrix * cameraMatrix; - m_centerNearPlane = m_eye + m_view.normalized(); + m_centerNearPlane = m_eye + m_viewNormalized; + m_centerNearPlaneMercator = m_eyeMercator + m_viewNormalized * m_nearPlaneMercator; + + // TODO: support tilting angles > 90.0, if desired. And flip the bottom corners with the top corners, if needed + // by clipper. + + // The following formula is used to have a growing epsilon with the zoom level, + // in order not to have too large values at low zl, which would overflow when converted to Clipper::cInt. + const double upperBoundEpsilon = 1.0 / std::pow(10, 1.0 + m_cameraData.zoomLevel() / 5.0); + const double elevationUpperBound = 90.0 - upperBoundEpsilon; + const double maxRayElevation = qMin(elevationUpperBound - m_cameraData.tilt(), verticalHalfFOV); + double maxHalfAperture = 0; + double verticalEstateToSkip = 0; + if (maxRayElevation < verticalHalfFOV) { + maxHalfAperture = tan(QLocationUtils::radians(maxRayElevation)); + verticalEstateToSkip = 1.0 - maxHalfAperture / verticalAperture; + } + + QDoubleVector2D tl = viewportToWrappedMapProjection(QDoubleVector2D(-1, -1 + verticalEstateToSkip )); + QDoubleVector2D tr = viewportToWrappedMapProjection(QDoubleVector2D( 1, -1 + verticalEstateToSkip )); + QDoubleVector2D bl = viewportToWrappedMapProjection(QDoubleVector2D(-1, 1 )); + QDoubleVector2D br = viewportToWrappedMapProjection(QDoubleVector2D( 1, 1 )); + + QList<QDoubleVector2D> mapRect; + mapRect.push_back(QDoubleVector2D(-1.0, 1.0)); + mapRect.push_back(QDoubleVector2D( 2.0, 1.0)); + mapRect.push_back(QDoubleVector2D( 2.0, 0.0)); + mapRect.push_back(QDoubleVector2D(-1.0, 0.0)); + + QList<QDoubleVector2D> viewportRect; + viewportRect.push_back(bl); + viewportRect.push_back(br); + viewportRect.push_back(tr); + viewportRect.push_back(tl); + + c2t::clip2tri clipper; + clipper.clearClipper(); + clipper.addSubjectPath(QClipperUtils::qListToPath(mapRect), true); + clipper.addClipPolygon(QClipperUtils::qListToPath(viewportRect)); + + Paths res = clipper.execute(c2t::clip2tri::Intersection); + m_visibleRegion.clear(); + if (res.size()) + m_visibleRegion = QClipperUtils::pathToQList(res[0]); // Intersection between two convex quadrilaterals should always be a single polygon +} + +/* + * + * Line implementation + * + */ + +QGeoProjectionWebMercator::Line2D::Line2D() +{ + +} + +QGeoProjectionWebMercator::Line2D::Line2D(const QDoubleVector2D &linePoint, const QDoubleVector2D &lineDirection) + : m_point(linePoint), m_direction(lineDirection.normalized()) +{ + +} + +bool QGeoProjectionWebMercator::Line2D::isValid() const +{ + return (m_direction.length() > 0.5); +} + +/* + * + * Plane implementation + * + */ + +QGeoProjectionWebMercator::Plane::Plane() +{ + +} + +QGeoProjectionWebMercator::Plane::Plane(const QDoubleVector3D &planePoint, const QDoubleVector3D &planeNormal) + : m_point(planePoint), m_normal(planeNormal.normalized()) { } + +QDoubleVector3D QGeoProjectionWebMercator::Plane::lineIntersection(const QDoubleVector3D &linePoint, const QDoubleVector3D &lineDirection) const +{ + QDoubleVector3D w = linePoint - m_point; + // s = -n.dot(w) / n.dot(u). p = p0 + su; u is lineDirection + double s = QDoubleVector3D::dotProduct(-m_normal, w) / QDoubleVector3D::dotProduct(m_normal, lineDirection); + return linePoint + lineDirection * s; +} + +QGeoProjectionWebMercator::Line2D QGeoProjectionWebMercator::Plane::planeXYIntersection() const +{ + // cross product of the two normals for the line direction + QDoubleVector3D lineDirection = QDoubleVector3D::crossProduct(m_normal, xyNormal); + lineDirection.setZ(0.0); + lineDirection.normalize(); + + // cross product of the line direction and the plane normal to find the direction on the plane + // intersecting the xy plane + QDoubleVector3D directionToXY = QDoubleVector3D::crossProduct(m_normal, lineDirection); + QDoubleVector3D p = xyPlane.lineIntersection(m_point, directionToXY); + return Line2D(p.toVector2D(), lineDirection.toVector2D()); +} + +bool QGeoProjectionWebMercator::Plane::isValid() const +{ + return (m_normal.length() > 0.5); } QT_END_NAMESPACE |