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class TGeoCompositeShape: public TGeoBBox

 TGeoCompositeShape - class handling Boolean composition of shapes

   Composite shapes are Boolean combination of two or more shape
 components. The supported boolean operations are union (+), intersection (*)
 and subtraction. Composite shapes derive from the base TGeoShape class,
 therefore providing all shape features : computation of bounding box, finding
 if a given point is inside or outside the combination, as well as computing the
 distance to entering/exiting. It can be directly used for creating volumes or
 used in the definition of other composite shapes.
   Composite shapes are provided in order to complement and extend the set of
 basic shape primitives. They have a binary tree internal structure, therefore
 all shape-related geometry queries are signals propagated from top level down
 to the final leaves, while the provided answers are assembled and interpreted
 back at top. This CSG hierarchy is effective for small number of components,
 while performance drops dramatically for large structures. Building a complete
 geometry in this style is virtually possible but highly not recommended.

   Structure of composite shapes

   A composite shape can always be regarded as the result of a Boolean operation
 between only two shape components. All information identifying these two
 components as well as their positions with respect to the frame of the composite
 is represented by an object called Boolean node. A composite shape just have
 a pointer to such a Boolean node. Since the shape components may also be
 composites, they will also contain binary Boolean nodes branching other two
 shapes in the hierarcy. Any such branch ends-up when the final leaves are no
 longer composite shapes, but basic primitives.

/* */

   Suppose that A, B, C and D represent basic shapes, we will illustrate
 how the internal representation of few combinations look like. We do this
 only for the sake of understanding how to create them in a proper way, since
 the user interface for this purpose is in fact very simple. We will ignore
 for the time being the positioning of components. The definition of a composite
 shape takes an expression where the identifiers are shape names. The
 expression is parsed and decomposed in 2 sub-expressions and the top-level
 Boolean operator.

 1.     A+B+C
   This represent the union of A, B and C. Both union operators are at the
 same level. Since:
        A+B+C = (A+B)+C = A+(B+C)
 the first (+) is taken as separator, hence the expression splitted:
        A and B+C
 A Boolean node of type TGeoUnion("A", "B+C") is created. This tries to replace
 the 2 expressions by actual pointers to corresponding shapes.
 The first expression (A) contains no operators therefore is interpreted as
 representing a shape. The shape named "A" is searched into the list of shapes
 handled by the manager class and stored as the "left" shape in the Boolean
 union node. Since the second expression is not yet fully decomposed, the "right"
 shape in the combination is created as a new composite shape. This will split
 at its turn B+C into B and C and create a TGeoUnion("B","C"). The B and C
 identifiers will be looked for and replaced by the pointers to the actual shapes
 into the new node. Finally, the composite "A+B+C" will be represented as:

   [A+B+C] = (+)             B
                |           |
                 [B+C] = (+)

 where [] is a composite shape, (+) is a Boolean node of type union and A, B,
 C are pointers to the corresponding shapes.
   Building this composite shapes takes the following line :
      TGeoCompositeShape *cs1 = new TGeoCompositeShape("CS1", "A+B+C");

 2.      (A+B)\(C+D)
   This expression means: subtract the union of C and D from the union of A and
 B. The usage of paranthesys to force operator precedence is always recommended.
 The representation of the corresponding composite shape looks like:

                       [A+B] = (+)
                      |           |
   [(A+B)\(C+D)] = (\)           C B
                      |         |

      TGeoCompositeShape *cs2 = new TGeoCompositeShape("CS2", "(A+B)\(C+D)");

   Building composite shapes as in the 2 examples above is not always quite
 usefull since we were using unpositioned shapes. When suplying just shape
 names as identifiers, the created boolean nodes will assume that the shapes
 are positioned with an identity transformation with respect to the frame of
 the created composite. In order to provide some positioning of the combination
 components, we have to attach after each shape identifier the name of an
 existing transformation, separated by a colon. Obviously all transformations
 created for this purpose have to be objects with unique names in order to be
 properly substituted during parsing.
   Let's look at the code implementing the second example :

      TGeoTranslation *t1 = new TGeoTranslation("T1",0,0,-20);
      TGeoTranslation *t2 = new TGeoTranslation("T2",0,0, 20);
      TGeoRotation *r1 = new TGeoRotation("R1"); // transformations need names
      r1->SetAngles(90,30,90,120,0,0); // rotation with 30 degrees about Z
      TGeoTube *a = new TGeoTube(0, 10,20);
      a->SetName("A");                 // shapes need names too
      TGeoTube *b = new TGeoTube(0, 20,20);
      TGeoBBox *c = new TGeoBBox(10,10,50);
      TGeoBBox *d = new TGeoBBox(50,10,10);

      TGeoCompositeShape *cs;
      cs = new TGeoCompositeShape("CS", "(A:t1+B:t2)\(C+D:r1)");

   The newly created composite looks like 2 cylinders of different radii sitting
 one on top of the other and having 2 rectangular holes : a longitudinal one
 along Z axis corresponding to C and an other one in the XY plane due to D.
   One should have in mind that the same shape or matrix identifier can be
 used many times in the same expression. For instance:


 is a valid expression. Expressions that cannot be parsed or identifiers that
 cannot be substituted by existing objects generate error messages.
   Composite shapes can be subsequently used for defining volumes. Moreover,
 these volumes may have daughters but these have to obbey overlapping/extruding
 rules (see TGeoVolume). Volumes created based on composite shapes cannot be
 divided. Visualization of such volumes is currently not implemented.

Function Members (Methods)

TGeoCompositeShape(const char* expression)
TGeoCompositeShape(const char* name, const char* expression)
TGeoCompositeShape(const char* name, TGeoBoolNode* node)
voidTObject::AbstractMethod(const char* method) const
virtual voidTObject::AppendPad(Option_t* option = "")
static Bool_tTGeoBBox::AreOverlapping(const TGeoBBox* box1, const TGeoMatrix* mat1, const TGeoBBox* box2, const TGeoMatrix* mat2)
static Double_tTGeoShape::Big()
virtual voidTObject::Browse(TBrowser* b)
virtual Double_tCapacity() const
static TClass*Class()
virtual const char*TObject::ClassName() const
virtual voidTNamed::Clear(Option_t* option = "")
virtual TObject*TNamed::Clone(const char* newname = "") const
virtual Int_tTNamed::Compare(const TObject* obj) const
virtual voidComputeBBox()
static Double_tTGeoShape::ComputeEpsMch()
virtual voidComputeNormal(Double_t* point, Double_t* dir, Double_t* norm)
virtual Bool_tContains(Double_t* point) const
virtual voidTNamed::Copy(TObject& named) const
virtual Bool_tTGeoBBox::CouldBeCrossed(Double_t* point, Double_t* dir) const
virtual voidTObject::Delete(Option_t* option = "")MENU
virtual Int_tTGeoBBox::DistancetoPrimitive(Int_t px, Int_t py)
virtual Double_tDistFromInside(Double_t* point, Double_t* dir, Int_t iact = 1, Double_t step = TGeoShape::Big(), Double_t* safe = 0) const
virtual Double_tDistFromOutside(Double_t* point, Double_t* dir, Int_t iact = 1, Double_t step = TGeoShape::Big(), Double_t* safe = 0) const
static Double_tTGeoShape::DistToPhiMin(Double_t* point, Double_t* dir, Double_t s1, Double_t c1, Double_t s2, Double_t c2, Double_t sm, Double_t cm, Bool_t in = kTRUE)
virtual TGeoVolume*Divide(TGeoVolume* voldiv, const char* divname, Int_t iaxis, Int_t ndiv, Double_t start, Double_t step)
virtual voidTGeoShape::Draw(Option_t* option = "")MENU
virtual voidTObject::DrawClass() constMENU
virtual TObject*TObject::DrawClone(Option_t* option = "") constMENU
virtual voidTObject::Dump() constMENU
static Double_tTGeoShape::EpsMch()
virtual voidTObject::Error(const char* method, const char* msgfmt) const
virtual voidTObject::Execute(const char* method, const char* params, Int_t* error = 0)
virtual voidTObject::Execute(TMethod* method, TObjArray* params, Int_t* error = 0)
virtual voidTGeoShape::ExecuteEvent(Int_t event, Int_t px, Int_t py)
virtual voidTObject::Fatal(const char* method, const char* msgfmt) const
virtual voidTNamed::FillBuffer(char*& buffer)
virtual TObject*TObject::FindObject(const char* name) const
virtual TObject*TObject::FindObject(const TObject* obj) const
virtual const char*TGeoBBox::GetAxisName(Int_t iaxis) const
virtual Double_tTGeoBBox::GetAxisRange(Int_t iaxis, Double_t& xlo, Double_t& xhi) const
TGeoBoolNode*GetBoolNode() const
virtual voidGetBoundingCylinder(Double_t*) const
virtual const TBuffer3D&TGeoBBox::GetBuffer3D(Int_t reqSections, Bool_t localFrame) const
virtual Int_tTGeoBBox::GetByteCount() const
virtual Option_t*TObject::GetDrawOption() const
static Long_tTObject::GetDtorOnly()
virtual Double_tTGeoBBox::GetDX() const
virtual Double_tTGeoBBox::GetDY() const
virtual Double_tTGeoBBox::GetDZ() const
virtual Double_tTGeoBBox::GetFacetArea(Int_t index = 0) const
virtual Int_tTGeoBBox::GetFittingBox(const TGeoBBox* parambox, TGeoMatrix* mat, Double_t& dx, Double_t& dy, Double_t& dz) const
virtual const char*TObject::GetIconName() const
Int_tTGeoShape::GetId() const
virtual TGeoShape*GetMakeRuntimeShape(TGeoShape*, TGeoMatrix*) const
virtual voidGetMeshNumbers(Int_t& nvert, Int_t& nsegs, Int_t& npols) const
virtual const char*TGeoShape::GetName() const
virtual Int_tGetNmeshVertices() const
virtual char*TObject::GetObjectInfo(Int_t px, Int_t py) const
static Bool_tTObject::GetObjectStat()
virtual Option_t*TObject::GetOption() const
virtual const Double_t*TGeoBBox::GetOrigin() const
char*TGeoShape::GetPointerName() const
virtual Bool_tTGeoBBox::GetPointsOnFacet(Int_t index, Int_t npoints, Double_t* array) const
virtual Bool_tGetPointsOnSegments(Int_t, Double_t*) const
virtual const char*TNamed::GetTitle() const
static TGeoMatrix*TGeoShape::GetTransform()
virtual UInt_tTObject::GetUniqueID() const
virtual Bool_tTObject::HandleTimer(TTimer* timer)
virtual ULong_tTNamed::Hash() const
virtual voidTObject::Info(const char* method, const char* msgfmt) const
virtual Bool_tTObject::InheritsFrom(const char* classname) const
virtual Bool_tTObject::InheritsFrom(const TClass* cl) const
virtual voidTObject::Inspect() constMENU
virtual voidInspectShape() const
voidTObject::InvertBit(UInt_t f)
voidTGeoShape::InvertShapeBit(UInt_t f)
virtual TClass*IsA() const
static Bool_tTGeoShape::IsCloseToPhi(Double_t epsil, Double_t* point, Double_t c1, Double_t s1, Double_t c2, Double_t s2)
virtual Bool_tIsComposite() const
static Bool_tTGeoShape::IsCrossingSemiplane(Double_t* point, Double_t* dir, Double_t cphi, Double_t sphi, Double_t& snext, Double_t& rxy)
virtual Bool_tIsCylType() const
virtual Bool_tTObject::IsEqual(const TObject* obj) const
virtual Bool_tTObject::IsFolder() const
static Bool_tTGeoShape::IsInPhiRange(Double_t* point, Double_t phi1, Double_t phi2)
virtual Bool_tTGeoBBox::IsNullBox() const
Bool_tTObject::IsOnHeap() const
virtual Bool_tTGeoShape::IsReflected() const
Bool_tTGeoShape::IsRunTimeShape() const
static Bool_tTGeoShape::IsSameWithinTolerance(Double_t a, Double_t b)
static Bool_tTGeoShape::IsSegCrossing(Double_t x1, Double_t y1, Double_t x2, Double_t y2, Double_t x3, Double_t y3, Double_t x4, Double_t y4)
virtual Bool_tTNamed::IsSortable() const
Bool_tTGeoShape::IsValid() const
virtual Bool_tTGeoBBox::IsValidBox() const
Bool_tTObject::IsZombie() const
virtual voidTNamed::ls(Option_t* option = "") const
virtual TBuffer3D*TGeoBBox::MakeBuffer3D() const
voidMakeNode(const char* expression)
voidTObject::MayNotUse(const char* method) const
static voidTGeoShape::NormalPhi(Double_t* point, Double_t* dir, Double_t* norm, Double_t c1, Double_t s1, Double_t c2, Double_t s2)
virtual Bool_tTObject::Notify()
static voidTObject::operator delete(void* ptr)
static voidTObject::operator delete(void* ptr, void* vp)
static voidTObject::operator delete[](void* ptr)
static voidTObject::operator delete[](void* ptr, void* vp)
void*TObject::operator new(size_t sz)
void*TObject::operator new(size_t sz, void* vp)
void*TObject::operator new[](size_t sz)
void*TObject::operator new[](size_t sz, void* vp)
virtual voidTGeoShape::Paint(Option_t* option = "")
virtual Bool_tPaintComposite(Option_t* option = "") const
virtual voidTObject::Pop()
virtual voidTNamed::Print(Option_t* option = "") const
virtual Int_tTObject::Read(const char* name)
virtual voidTObject::RecursiveRemove(TObject* obj)
voidTObject::ResetBit(UInt_t f)
voidTGeoShape::ResetShapeBit(UInt_t f)
virtual Double_tSafety(Double_t* point, Bool_t in = kTRUE) const
static Double_tTGeoShape::SafetyPhi(Double_t* point, Bool_t in, Double_t phi1, Double_t phi2)
virtual voidTObject::SaveAs(const char* filename = "", Option_t* option = "") constMENU
virtual voidSavePrimitive(ostream& out, Option_t* option = "")
voidTObject::SetBit(UInt_t f)
voidTObject::SetBit(UInt_t f, Bool_t set)
voidTGeoBBox::SetBoxDimensions(Double_t dx, Double_t dy, Double_t dz, Double_t* origin = 0)
voidTGeoBBox::SetBoxPoints(Double_t* points) const
virtual voidSetDimensions(Double_t*)
virtual voidTObject::SetDrawOption(Option_t* option = "")MENU
static voidTObject::SetDtorOnly(void* obj)
voidTGeoShape::SetId(Int_t id)
virtual voidTNamed::SetName(const char* name)MENU
virtual voidTNamed::SetNameTitle(const char* name, const char* title)
static voidTObject::SetObjectStat(Bool_t stat)
virtual voidSetPoints(Double_t* points) const
virtual voidSetPoints(Float_t* points) const
voidTGeoShape::SetRuntime(Bool_t flag = kTRUE)
virtual voidTGeoBBox::SetSegsAndPols(TBuffer3D& buffer) const
voidTGeoShape::SetShapeBit(UInt_t f)
voidTGeoShape::SetShapeBit(UInt_t f, Bool_t set)
virtual voidTNamed::SetTitle(const char* title = "")MENU
static voidTGeoShape::SetTransform(TGeoMatrix* matrix)
virtual voidTObject::SetUniqueID(UInt_t uid)
Int_tTGeoShape::ShapeDistancetoPrimitive(Int_t numpoints, Int_t px, Int_t py) const
virtual voidShowMembers(TMemberInspector& insp, char* parent)
virtual Int_tTNamed::Sizeof() const
virtual voidSizeof3D() const
virtual voidStreamer(TBuffer& b)
voidStreamerNVirtual(TBuffer& b)
virtual voidTObject::SysError(const char* method, const char* msgfmt) const
Bool_tTObject::TestBit(UInt_t f) const
Int_tTObject::TestBits(UInt_t f) const
Bool_tTGeoShape::TestShapeBit(UInt_t f) const
Int_tTGeoShape::TestShapeBits(UInt_t f) const
static Double_tTGeoShape::Tolerance()
virtual voidTObject::UseCurrentStyle()
virtual voidTObject::Warning(const char* method, const char* msgfmt) const
virtual Int_tTObject::Write(const char* name = 0, Int_t option = 0, Int_t bufsize = 0)
virtual Int_tTObject::Write(const char* name = 0, Int_t option = 0, Int_t bufsize = 0) const
TGeoCompositeShape(const TGeoCompositeShape& gcs)
virtual voidTObject::DoError(int level, const char* location, const char* fmt, va_list va) const
virtual voidTGeoBBox::FillBuffer3D(TBuffer3D& buffer, Int_t reqSections, Bool_t localFrame) const
Int_tTGeoShape::GetBasicColor() const
TGeoCompositeShape&operator=(const TGeoCompositeShape& gcs)
voidTGeoShape::TransformPoints(Double_t* points, UInt_t NbPoints) const

Data Members

TGeoBoolNode*fNodetop boolean node

Class Charts

Inheritance Inherited Members Includes Libraries
Class Charts

Function documentation

 Default constructor
TGeoCompositeShape(const char *name, const char *expression)
 Default constructor
TGeoCompositeShape(const char *expression)
 Default constructor
TGeoCompositeShape(const char *name, TGeoBoolNode *node)
 Constructor with a Boolean node
Double_t Capacity() const
 Computes capacity of this shape [length^3] by sampling with 1% error.
void ComputeBBox()
 compute bounding box of the sphere
void ComputeNormal(Double_t* point, Double_t* dir, Double_t* norm)
 Computes normal vector in POINT to the composite shape.
Bool_t Contains(Double_t* point) const
 Tests if point is inside the shape.
Double_t DistFromOutside(Double_t* point, Double_t* dir, Int_t iact = 1, Double_t step = TGeoShape::Big(), Double_t* safe = 0) const
 Compute distance from outside point to this composite shape.
 Check if the bounding box is crossed within the requested distance
Double_t DistFromInside(Double_t* point, Double_t* dir, Int_t iact = 1, Double_t step = TGeoShape::Big(), Double_t* safe = 0) const
 Compute distance from inside point to outside of this composite shape.
TGeoVolume * Divide(TGeoVolume* voldiv, const char* divname, Int_t iaxis, Int_t ndiv, Double_t start, Double_t step)
 Divide all range of iaxis in range/step cells
void GetMeshNumbers(Int_t& nvert, Int_t& nsegs, Int_t& npols) const
 Returns numbers of vertices, segments and polygons composing the shape mesh.
void InspectShape() const
 print shape parameters
void MakeNode(const char* expression)
 Make a booleann node according to the top level boolean operation of expression.
 Propagates signal to branches until expression is fully decomposed.
   printf("Making node for : %s\n", expression);
Bool_t PaintComposite(Option_t* option = "") const
 Paint this composite shape into the current 3D viewer
 Returns bool flag indicating if the caller should continue to
 paint child objects
void RegisterYourself()
 Register the shape and all components to TGeoManager class.
Double_t Safety(Double_t* point, Bool_t in = kTRUE) const
 computes the closest distance from given point to this shape, according
 to option. The matching point on the shape is stored in spoint.
void SavePrimitive(ostream& out, Option_t* option = "")
 Save a primitive as a C++ statement(s) on output stream "out".
void SetPoints(Double_t *points)
 create points for a composite shape
void SetPoints(Float_t *points)
 create points for a composite shape
void Sizeof3D() const
 compute size of this 3D object
Int_t GetNmeshVertices() const
 Return number of vertices of the mesh representation
TGeoCompositeShape(const TGeoCompositeShape& gcs)
{ }
TGeoCompositeShape& operator=(const TGeoCompositeShape& gcs)
TGeoBoolNode * GetBoolNode() const
{return fNode;}
void GetBoundingCylinder(Double_t* ) const
TGeoShape * GetMakeRuntimeShape(TGeoShape* , TGeoMatrix* ) const
{return 0;}
Bool_t GetPointsOnSegments(Int_t , Double_t* ) const
{return kFALSE;}
Bool_t IsComposite() const
{return kTRUE;}
Bool_t IsCylType() const
{return kFALSE;}
void SetDimensions(Double_t* )