Surface classes

All classes which represent a thin surface in ACTS inherit from the common virtual base class {class}Acts::Surface, which defines the public interface of all surfaces. While the different concrete surface classes are defined by their respective native local coordinate system, the shapes on these surfaces are defined by classes that inherit from {class}Acts::SurfaceBounds, which every surface must provide. In case of boundless surfaces, a special {class}Acts::InfiniteBounds class is available.

Each {class}Acts::Surface instance reports its type from {func}Acts::Surface::type():

:::{doxygenenum} Acts::Surface::SurfaceType :::

Surface Type	Local Coordinates	Bound Types available
{class}Acts::ConeSurface	$[r\phi, z]$	{class}Acts::ConeBounds
{class}Acts::CylinderSurface	$[r, \phi]$	{class}Acts::CylinderBounds
{class}Acts::DiscSurface	$[r, \phi]$	{class}Acts::RadialBounds, {class}Acts::DiscTrapezoidBounds
{class}Acts::PlaneSurface	$[x, y]$	{class}Acts::RectangleBounds, {class}Acts::TrapezoidBounds, {class}Acts::InfiniteBounds, {class}Acts::EllipseBounds
{class}Acts::PerigeeSurface, {class}Acts::StrawSurface	$[d, z]$	{class}Acts::CylinderBounds
{class}Acts::LineSurface	$[d_0, z_0]$	{class}Acts::LineBounds

In an ideal setup, the coordinate systems also define the readout
measurement directions. In such a case, a track prediction from the
propagation will already be in the correct frame of the measurement and
residual or compatibility checks will not need additional coordinate
transformations.

Plane surface

:::{doxygenclass} Acts::PlaneSurface

members: globalToLocal,localToGlobal,intersect,normal

:::

Disc surface

:::{doxygenclass} Acts::DiscSurface

members: globalToLocal,localToGlobal,intersect,normal,mergedWith

:::

Cylinder surface

:::{doxygenclass} Acts::CylinderSurface

members: globalToLocal,localToGlobal,intersect,normal,mergedWith

:::

Cone surface

:::{doxygenclass} Acts::ConeSurface

members: globalToLocal,localToGlobal,intersect,normal

:::

Line surface

{class}Acts::LineSurface is a special kind of surface that depends on a reference direction, typically the unit momentum direction $\vec d$ of a particle. A point in space is considered on surface if and only if it coincides with the point of closest approach between the direction vector $\vec d$ and the line direction vector $\vec z$. As such, the function {func}Acts::LineSurface::globalToLocal can fail, if the argument position and direction do not fulfill this criterion. It is pure-virtual, meaning that it can not be instantiated on its own.

:::{doxygenclass} Acts::LineSurface

members: globalToLocal,localToGlobal,intersect,normal

:::

Straw surface

:::{doxygenclass} Acts::StrawSurface

members: false

:::

Perigee surface

:::{doxygenclass} Acts::PerigeeSurface

members: false

:::

API listings

:::{doxygenclass} Acts::Surface :::