Set initial extent of a new 3D view to extent of the main canvas

Author: wonder-sk

src/3d/qgscameracontroller.cpp

@@ -282,7 +282,12 @@ void QgsCameraController::frameTriggered( float dt )
 
 void QgsCameraController::resetView( float distance )
 {
-  setCameraData( 0, 0, distance );
+  setViewFromTop( 0, 0, distance );
+}
+
+void QgsCameraController::setViewFromTop( float worldX, float worldY, float distance, float yaw )
+{
+  setCameraData( worldX, worldY, distance, 0, yaw );
   // a basic setup to make frustum depth range long enough that it does not cull everything
   mCamera->setNearPlane( distance / 2 );
   mCamera->setFarPlane( distance * 2 );

src/3d/qgscameracontroller.h

@@ -57,6 +57,9 @@ class _3D_EXPORT QgsCameraController : public Qt3DCore::QEntity
     //! Move camera back to the initial position (looking down towards origin of world's coordinates)
     void resetView( float distance );
 
+    //! 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 QVector3D &vWorld );
 
@@ -85,8 +88,8 @@ class _3D_EXPORT QgsCameraController : public Qt3DCore::QEntity
     {
       float x = 0, y = 0;  // ground point towards which the camera is looking
       float dist = 40;  // distance of camera from the point it is looking at
-      float pitch = 0; // aircraft nose up/down (0 = looking straight down to the plane)
-      float yaw = 0;   // aircraft nose left/right
+      float pitch = 0; // aircraft nose up/down (0 = looking straight down to the plane). angle in degrees
+      float yaw = 0;   // aircraft nose left/right. angle in degrees
 
       bool operator==( const CameraData &other ) const
       {

src/app/3d/qgs3dmapcanvas.cpp

@@ -82,3 +82,10 @@ void Qgs3DMapCanvas::resetView()
 {
   mScene->viewZoomFull();
 }
+
+void Qgs3DMapCanvas::setViewFromTop( const QgsPointXY &center, float distance, float rotation )
+{
+  float worldX = center.x() - mMap->originX();
+  float worldY = center.y() - mMap->originY();
+  mScene->cameraController()->setViewFromTop( worldX, -worldY, distance, rotation );
+}

src/app/3d/qgs3dmapcanvas.h

@@ -26,6 +26,7 @@ namespace Qt3DExtras
 class Qgs3DMapSettings;
 class Qgs3DMapScene;
 class QgsCameraController;
+class QgsPointXY;
 
 
 class Qgs3DMapCanvas : public QWidget
@@ -46,6 +47,9 @@ class Qgs3DMapCanvas : public QWidget
     //! Resets camera position to the default: looking down at the origin of world coordinates
     void resetView();
 
+    //! Sets camera position to look down at the given point (in map coordinates) in given distance from plane with zero elevation
+    void setViewFromTop( const QgsPointXY &center, float distance, float rotation = 0 );
+
   protected:
     void resizeEvent( QResizeEvent *ev ) override;
 

src/app/qgisapp.cpp

@@ -10244,6 +10244,10 @@ void QgisApp::new3DMapCanvas()
     map->setTerrainGenerator( flatTerrain );
 
     dock->setMapSettings( map );
+
+    QgsRectangle extent = mMapCanvas->extent();
+    float dist = qMax( extent.width(), extent.height() );
+    dock->mapCanvas3D()->setViewFromTop( mMapCanvas->extent().center(), dist, mMapCanvas->rotation() );
   }
 #endif
 }