Marble

SphericalProjection.cpp
1// SPDX-License-Identifier: LGPL-2.1-or-later
2//
3// SPDX-FileCopyrightText: 2007 Inge Wallin <ingwa@kde.org>
4// SPDX-FileCopyrightText: 2007-2014 Torsten Rahn <rahn@kde.org>
5// SPDX-FileCopyrightText: 2009 Patrick Spendrin <ps_ml@gmx.de>
6// SPDX-FileCopyrightText: 2012 Cezar Mocan <mocancezar@gmail.com>
7//
8
9// Local
10#include "SphericalProjection.h"
11#include "AbstractProjection_p.h"
12
13#include "MarbleDebug.h"
14
15// Marble
16#include "ViewportParams.h"
17#include "GeoDataPoint.h"
18#include "GeoDataLineString.h"
19#include "GeoDataCoordinates.h"
20#include "MarbleGlobal.h"
21#include "AzimuthalProjection_p.h"
22
23#include <QIcon>
24
25#define SAFE_DISTANCE
26
27namespace Marble
28{
29
30class SphericalProjectionPrivate : public AzimuthalProjectionPrivate
31{
32 public:
33
34 explicit SphericalProjectionPrivate( SphericalProjection * parent );
35
36 Q_DECLARE_PUBLIC( SphericalProjection )
37};
38
40 : AzimuthalProjection( new SphericalProjectionPrivate( this ) )
41{
42 setMinLat( minValidLat() );
43 setMaxLat( maxValidLat() );
44}
45
46SphericalProjection::SphericalProjection( SphericalProjectionPrivate *dd )
48{
49 setMinLat( minValidLat() );
50 setMaxLat( maxValidLat() );
51}
52
53SphericalProjection::~SphericalProjection()
54{
55}
56
57SphericalProjectionPrivate::SphericalProjectionPrivate( SphericalProjection * parent )
58 : AzimuthalProjectionPrivate( parent )
59{
60}
61
63{
64 return QObject::tr( "Globe" );
65}
66
68{
69 return QObject::tr( "<p><b>Orthographic Projection</b> (\"orthogonal\")</p><p>Applications: A perspective projection that is used to display the hemisphere of a globe as it appears from outer space.</p>" );
70}
71
73{
74 return QIcon(QStringLiteral(":/icons/map-globe.png"));
75}
76
78 const ViewportParams *viewport,
79 qreal &x, qreal &y, bool &globeHidesPoint ) const
80{
81 const qreal altitude = coordinates.altitude();
82 const qreal absoluteAltitude = altitude + EARTH_RADIUS;
83 Quaternion qpos = coordinates.quaternion();
84
85 qpos.rotateAroundAxis( viewport->planetAxisMatrix() );
86
87 const qreal radius = viewport->radius();
88 const qreal pixelAltitude = (radius / EARTH_RADIUS * absoluteAltitude);
89 if (altitude < 10000) {
90 // Skip placemarks at the other side of the earth.
91 if ( qpos.v[Q_Z] < 0 ) {
92 globeHidesPoint = true;
93 return false;
94 }
95 }
96 else {
97 qreal earthCenteredX = pixelAltitude * qpos.v[Q_X];
98 qreal earthCenteredY = pixelAltitude * qpos.v[Q_Y];
99
100 // Don't draw high placemarks (e.g. satellites) that aren't visible.
101 if ( qpos.v[Q_Z] < 0
102 && ( ( earthCenteredX * earthCenteredX
103 + earthCenteredY * earthCenteredY )
104 < radius * radius ) ) {
105 globeHidesPoint = true;
106 return false;
107 }
108 }
109
110 const qreal width = viewport->width();
111 const qreal height = viewport->height();
112
113 // Let (x, y) be the position on the screen of the placemark..
114 x = (width / 2 + pixelAltitude * qpos.v[Q_X]);
115 y = (height / 2 - pixelAltitude * qpos.v[Q_Y]);
116
117 // Skip placemarks that are outside the screen area
118 if (x < 0 || x >= width || y < 0 || y >= height) {
119 globeHidesPoint = false;
120 return false;
121 }
122
123 globeHidesPoint = false;
124 return true;
125}
126
128 const ViewportParams *viewport,
129 qreal *x, qreal &y,
130 int &pointRepeatNum,
131 const QSizeF& size,
132 bool &globeHidesPoint ) const
133{
134 pointRepeatNum = 0;
135 bool visible = screenCoordinates( coordinates, viewport, *x, y, globeHidesPoint );
136
137 // Skip placemarks that are outside the screen area
138 if ( *x + size.width() / 2.0 < 0.0 || *x >= viewport->width() + size.width() / 2.0
139 || y + size.height() / 2.0 < 0.0 || y >= viewport->height() + size.height() / 2.0 )
140 {
141 globeHidesPoint = false;
142 return false;
143 }
144
145 // This projection doesn't have any repetitions,
146 // so the number of screen points referring to the geopoint is one.
147 pointRepeatNum = 1;
148 return visible;
149}
150
151
152bool SphericalProjection::geoCoordinates( const int x, const int y,
153 const ViewportParams *viewport,
154 qreal& lon, qreal& lat,
155 GeoDataCoordinates::Unit unit ) const
156{
157 const qreal inverseRadius = 1.0 / (qreal)(viewport->radius());
158
159 const qreal qx = +(qreal)( x - viewport->width() / 2 ) * inverseRadius;
160 const qreal qy = -(qreal)( y - viewport->height() / 2 ) * inverseRadius;
161
162 if ( 1 <= qx * qx + qy * qy ) {
163 return false;
164 }
165
166 const qreal qz = sqrt( 1 - qx * qx - qy * qy );
167
168 Quaternion qpos( 0.0, qx, qy, qz );
169 qpos.rotateAroundAxis( viewport->planetAxis() );
170 qpos.getSpherical( lon, lat );
171
172 if ( unit == GeoDataCoordinates::Degree ) {
173 lon *= RAD2DEG;
174 lat *= RAD2DEG;
175 }
176
177 return true;
178}
179
180}
This file contains the headers for SphericalProjection.
This file contains the headers for ViewportParams.
virtual qreal maxValidLat() const
Returns the maximum (northern) latitude that is mathematically defined and reasonable.
virtual qreal minValidLat() const
Returns the minimum (southern) latitude that is mathematically defined and reasonable.
A base class for the Gnomonic and Orthographic (Globe) projections in Marble.
A 3d point representation.
qreal altitude() const
return the altitude of the Point in meters
Unit
enum used constructor to specify the units used
const Quaternion & quaternion() const
return a Quaternion with the used coordinates
QString description() const override
Returns a short user description of the projection that can be used in tooltips or dialogs.
SphericalProjection()
Construct a new SphericalProjection.
QString name() const override
Returns the user-visible name of the projection.
bool screenCoordinates(const GeoDataCoordinates &coordinates, const ViewportParams *params, qreal &x, qreal &y, bool &globeHidesPoint) const override
Get the screen coordinates corresponding to geographical coordinates in the map.
bool geoCoordinates(const int x, const int y, const ViewportParams *params, qreal &lon, qreal &lat, GeoDataCoordinates::Unit unit=GeoDataCoordinates::Degree) const override
Get the earth coordinates corresponding to a pixel in the map.
QIcon icon() const override
Returns an icon for the projection.
A public class that controls what is visible in the viewport of a Marble map.
Binds a QML item to a specific geodetic location in screen coordinates.
QString tr(const char *sourceText, const char *disambiguation, int n)
qreal height() const const
qreal width() const const
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