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src/3d/qgs3dmapscene.cpp

@@ -338,10 +338,17 @@ void Qgs3DMapScene::updateScene( bool forceUpdate )
   // Make our own projection matrix so that frustum culling done by the
   // entities isn't dependent on the current near/far planes, which would then
   // require multiple steps to stabilize.
-  QMatrix4x4 projMatrix;
-  projMatrix.setToIdentity();
-  // Just use some high values for the far plane so we don't have to custom-make the matrix.
-  projMatrix.perspective( camera->fieldOfView(), camera->aspectRatio(), 1, 1'000'000'000'000.0 );
+  // The matrix is constructed just like in QMatrix4x4::perspective(), but for
+  // all elements involving the near and far plane, the limit of the expression
+  // with the far plane going to infinity is taken.
+  float fovRadians = ( camera->fieldOfView() / 2.0f ) * static_cast<float>( M_PI ) / 180.0f;
+  float fovCotan = std::cos( fovRadians ) / std::sin( fovRadians );
+  QMatrix4x4 projMatrix(
+    fovCotan / camera->fieldOfView(), 0, 0, 0,
+    0, fovCotan, 0, 0,
+    0, 0, -1, -2,
+    0, 0, -1, 0
+  );
   sceneContext.viewProjectionMatrix = projMatrix * camera->viewMatrix();
 
 

src/3d/qgsvirtualpointcloudentity_p.cpp

@@ -140,7 +140,7 @@ void QgsVirtualPointCloudEntity::handleSceneUpdate( const SceneContext &sceneCon
     if ( !needsUpdate && box3D.isEmpty() )
       continue;
 
-    QgsAABB aabb = QgsAABB::fromBox3D( box3D, mBboxesEntity->vertexDataOrigin() );
+    QgsAABB aabb = QgsAABB::fromBox3D( box3D, mMapSettings->origin() );
     if ( !needsUpdate && Qgs3DUtils::isCullable( aabb, sceneContext.viewProjectionMatrix ) )
       continue;
 
@@ -190,7 +190,7 @@ QgsRange<float> QgsVirtualPointCloudEntity::getNearFarPlaneRange( const QMatrix4
   {
     for ( const QgsBox3D &box : mBboxes )
     {
-      QgsAABB aabb = QgsAABB::fromBox3D( box, mBboxesEntity->vertexDataOrigin() );
+      QgsAABB aabb = QgsAABB::fromBox3D( box, mMapSettings->origin() );
       float bboxfnear;
       float bboxffar;
       Qgs3DUtils::computeBoundingBoxNearFarPlanes( aabb, viewMatrix, bboxfnear, bboxffar );