[3d] Cleaned up code for camera translation + tests

Author: wonder-sk

src/3d/qgs3dmapsettings.cpp

@@ -211,16 +211,12 @@ void Qgs3DMapSettings::resolveReferences( const QgsProject &project )
 
 QgsVector3D Qgs3DMapSettings::mapToWorldCoordinates( const QgsVector3D &mapCoords ) const
 {
-  return QgsVector3D( mapCoords.x() - mOrigin.x(),
-                      -( mapCoords.z() - mOrigin.z() ),
-                      mapCoords.y() - mOrigin.y() );
+  return Qgs3DUtils::mapToWorldCoordinates( mapCoords, mOrigin );
 }
 
 QgsVector3D Qgs3DMapSettings::worldToMapCoordinates( const QgsVector3D &worldCoords ) const
 {
-  return QgsVector3D( worldCoords.x() + mOrigin.x(),
-                      -( worldCoords.z() + mOrigin.z() ),
-                      worldCoords.y() + mOrigin.y() );
+  return Qgs3DUtils::worldToMapCoordinates( worldCoords, mOrigin );
 }
 
 void Qgs3DMapSettings::setCrs( const QgsCoordinateReferenceSystem &crs )

src/3d/qgs3dutils.cpp

@@ -255,3 +255,39 @@ bool Qgs3DUtils::isCullable( const QgsAABB &bbox, const QMatrix4x4 &viewProjecti
   return out;
 }
 
+QgsVector3D Qgs3DUtils::mapToWorldCoordinates( const QgsVector3D &mapCoords, const QgsVector3D &origin )
+{
+  return QgsVector3D( mapCoords.x() - origin.x(),
+                      mapCoords.z() - origin.z(),
+                      -( mapCoords.y() - origin.y() ) );
+
+}
+
+QgsVector3D Qgs3DUtils::worldToMapCoordinates( const QgsVector3D &worldCoords, const QgsVector3D &origin )
+{
+  return QgsVector3D( worldCoords.x() + origin.x(),
+                      -worldCoords.z() + origin.y(),
+                      worldCoords.y() + origin.z() );
+}
+
+QgsVector3D Qgs3DUtils::transformWorldCoordinates( const QgsVector3D &worldPoint1, const QgsVector3D &origin1, const QgsCoordinateReferenceSystem &crs1, const QgsVector3D &origin2, const QgsCoordinateReferenceSystem &crs2 )
+{
+  QgsVector3D mapPoint1 = worldToMapCoordinates( worldPoint1, origin1 );
+  QgsVector3D mapPoint2 = mapPoint1;
+  if ( crs1 != crs2 )
+  {
+    // reproject if necessary
+    QgsCoordinateTransform ct( crs1, crs2 );
+    try
+    {
+      QgsPointXY pt = ct.transform( QgsPointXY( mapPoint1.x(), mapPoint1.y() ) );
+      mapPoint2.set( pt.x(), pt.y(), mapPoint1.z() );
+    }
+    catch ( const QgsCsException & )
+    {
+      // bad luck, can't reproject for some reason
+    }
+  }
+  return mapToWorldCoordinates( mapPoint2, origin2 );
+}
+

src/3d/qgs3dutils.h

@@ -84,6 +84,14 @@ class _3D_EXPORT Qgs3DUtils
         This is used to perform object culling checks.
     */
     static bool isCullable( const QgsAABB &bbox, const QMatrix4x4 &viewProjectionMatrix );
+
+    //! Converts map coordinates to 3D world coordinates (applies offset and turns (x,y,z) into (x,-z,y))
+    static QgsVector3D mapToWorldCoordinates( const QgsVector3D &mapCoords, const QgsVector3D &origin );
+    //! Converts 3D world coordinates to map coordinates (applies offset and turns (x,y,z) into (x,-z,y))
+    static QgsVector3D worldToMapCoordinates( const QgsVector3D &worldCoords, const QgsVector3D &origin );
+
+    //! Transforms a world point from (origin1, crs1) to (origin2, crs2)
+    static QgsVector3D transformWorldCoordinates( const QgsVector3D &worldPoint1, const QgsVector3D &origin1, const QgsCoordinateReferenceSystem &crs1, const QgsVector3D &origin2, const QgsCoordinateReferenceSystem &crs2 );
 };
 
 #endif // QGS3DUTILS_H

src/3d/qgscameracontroller.cpp

@@ -296,9 +296,14 @@ void QgsCameraController::setViewFromTop( float worldX, float worldY, float dist
   emit cameraChanged();
 }
 
-void QgsCameraController::translateWorld( const QgsVector3D &vWorld )
+QgsVector3D QgsCameraController::lookingAtPoint() const
 {
-  setCameraData( mCameraData.x - vWorld.x(), mCameraData.y + vWorld.y(), mCameraData.dist, mCameraData.pitch, mCameraData.yaw );
+  return QgsVector3D( mCameraData.x, 0, mCameraData.y );
+}
+
+void QgsCameraController::setLookingAtPoint( const QgsVector3D &point )
+{
+  setCameraData( point.x(), point.z(), mCameraData.dist, mCameraData.pitch, mCameraData.yaw );
   emit cameraChanged();
 }
 

src/3d/qgscameracontroller.h

@@ -61,8 +61,10 @@ class _3D_EXPORT QgsCameraController : public Qt3DCore::QEntity
     //! Sets camera to look down towards given point in world coordinate, in given distance from plane with zero elevation
     void setViewFromTop( float worldX, float worldY, float distance, float yaw = 0 );
 
-    //! Moves the point toward which the camera is looking - this is used when world origin changes (e.g. after terrain generator changes)
-    void translateWorld( const QgsVector3D &vWorld );
+    //! Returns the point in the world coordinates towards which the camera is looking
+    QgsVector3D lookingAtPoint() const;
+    //! Sets the point toward which the camera is looking - this is used when world origin changes (e.g. after terrain generator changes)
+    void setLookingAtPoint( const QgsVector3D &point );
 
   private:
     void setCameraData( float x, float y, float dist, float pitch = 0, float yaw = 0 );

src/3d/qgsvector3d.h

@@ -52,6 +52,15 @@ class _3D_EXPORT QgsVector3D
       mZ = z;
     }
 
+    bool operator==( const QgsVector3D &other ) const
+    {
+      return mX == other.mX && mY == other.mY && mZ == other.mZ;
+    }
+    bool operator!=( const QgsVector3D &other ) const
+    {
+      return !operator==( other );
+    }
+
     //! Returns sum of two vectors
     QgsVector3D operator+( const QgsVector3D &other )
     {

src/app/3d/qgs3dmapcanvasdockwidget.cpp

@@ -22,6 +22,7 @@
 #include "qgsmapcanvas.h"
 
 #include "qgs3dmapsettings.h"
+#include "qgs3dutils.h"
 
 #include <QBoxLayout>
 #include <QDialog>
@@ -86,15 +87,21 @@ void Qgs3DMapCanvasDockWidget::configure()
     return;
 
   QgsVector3D oldOrigin = map->origin();
+  QgsCoordinateReferenceSystem oldCrs = map->crs();
+  QgsVector3D oldLookingAt = mCanvas->cameraController()->lookingAtPoint();
 
   // update map
   w->apply();
 
-  QgsVector3D d = map->origin() - oldOrigin;
-  if ( !d.isNull() )
+  QgsVector3D p = Qgs3DUtils::transformWorldCoordinates(
+                    oldLookingAt,
+                    oldOrigin, oldCrs,
+                    map->origin(), map->crs() );
+
+  if ( p != oldLookingAt )
   {
     // apply() call has moved origin of the world so let's move camera so we look still at the same place
-    mCanvas->cameraController()->translateWorld( d );
+    mCanvas->cameraController()->setLookingAtPoint( p );
   }
 }
 

src/app/3d/qgs3dmapconfigwidget.cpp

@@ -108,7 +108,12 @@ void Qgs3DMapConfigWidget::apply()
 
   if ( needsUpdateOrigin )
   {
-    QgsPointXY center = mMap->terrainGenerator()->extent().center();
+    // reproject terrain's extent to map CRS
+    QgsRectangle te = mMap->terrainGenerator()->extent();
+    QgsCoordinateTransform terrainToMapTransform( mMap->terrainGenerator()->crs(), mMap->crs() );
+    te = terrainToMapTransform.transformBoundingBox( te );
+
+    QgsPointXY center = te.center();
     mMap->setOrigin( QgsVector3D( center.x(), center.y(), 0 ) );
   }
 

tests/src/3d/CMakeLists.txt

@@ -8,6 +8,8 @@ SET (util_SRCS)
 INCLUDE_DIRECTORIES(${CMAKE_CURRENT_SOURCE_DIR}
   ${CMAKE_SOURCE_DIR}/tests/core #for render checker class
   ${CMAKE_SOURCE_DIR}/src/3d
+  ${CMAKE_SOURCE_DIR}/src/3d/chunks
+  ${CMAKE_SOURCE_DIR}/src/3d/terrain
   ${CMAKE_SOURCE_DIR}/src/core
   ${CMAKE_SOURCE_DIR}/src/core/expression
   ${CMAKE_SOURCE_DIR}/src/core/auth
@@ -68,4 +70,5 @@ MACRO (ADD_QGIS_TEST testname testsrc)
   #  INSTALL_RPATH_USE_LINK_PATH true )
 ENDMACRO (ADD_QGIS_TEST)
 
+ADD_QGIS_TEST(3dutilstest testqgs3dutils.cpp)
 ADD_QGIS_TEST(tessellatortest testqgstessellator.cpp)

tests/src/3d/testqgs3dutils.cpp

@@ -0,0 +1,86 @@
+/***************************************************************************
+     testqgs3dutils.cpp
+     ----------------------
+    Date                 : November 2017
+    Copyright            : (C) 2017 by Martin Dobias
+    Email                : wonder dot sk at gmail dot com
+ ***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#include "qgstest.h"
+
+#include "qgs3dutils.h"
+
+
+/**
+ * \ingroup UnitTests
+ * This is a unit test for the node tool
+ */
+class TestQgs3DUtils : public QObject
+{
+    Q_OBJECT
+  public:
+    TestQgs3DUtils() = default;
+
+  private slots:
+    void initTestCase();// will be called before the first testfunction is executed.
+    void cleanupTestCase();// will be called after the last testfunction was executed.
+
+    void testTransforms();
+
+  private:
+};
+
+//runs before all tests
+void TestQgs3DUtils::initTestCase()
+{
+}
+
+//runs after all tests
+void TestQgs3DUtils::cleanupTestCase()
+{
+}
+
+void TestQgs3DUtils::testTransforms()
+{
+  QgsVector3D map123( 1, 2, 3 );
+
+  QgsVector3D world123 = Qgs3DUtils::mapToWorldCoordinates( map123, QgsVector3D() );
+  QCOMPARE( world123, QgsVector3D( 1, 3, -2 ) );
+
+  QgsVector3D world123map = Qgs3DUtils::worldToMapCoordinates( world123, QgsVector3D() );
+  QCOMPARE( world123map, map123 );
+
+  // now with non-zero origin
+
+  QgsVector3D origin( -10, -20, -30 );
+
+  QgsVector3D world123x = Qgs3DUtils::mapToWorldCoordinates( map123, origin );
+  QCOMPARE( world123x, QgsVector3D( 11, 33, -22 ) );
+
+  QgsVector3D world123xmap = Qgs3DUtils::worldToMapCoordinates( world123x, origin );
+  QCOMPARE( world123xmap, map123 );
+
+  //
+  // transform world point from one system to another
+  //
+
+  QgsVector3D worldPoint1( 5, 7, -6 );
+  QgsVector3D origin1( 10, 20, 30 );
+  QgsVector3D origin2( 1, 2, 3 );
+  QgsVector3D worldPoint2 = Qgs3DUtils::transformWorldCoordinates( worldPoint1, origin1, QgsCoordinateReferenceSystem(), origin2, QgsCoordinateReferenceSystem() );
+  QCOMPARE( worldPoint2, QgsVector3D( 14, 34, -24 ) );
+  // verify that both are the same map point
+  QgsVector3D mapPoint1 = Qgs3DUtils::worldToMapCoordinates( worldPoint1, origin1 );
+  QgsVector3D mapPoint2 = Qgs3DUtils::worldToMapCoordinates( worldPoint2, origin2 );
+  QCOMPARE( mapPoint1, mapPoint2 );
+}
+
+QGSTEST_MAIN( TestQgs3DUtils )
+#include "testqgs3dutils.moc"