BresenhamLineIterator class
An iterator to iterate over pixels along a straight line.
Contents
The iterator is created giving two points: a start and and end point.
The iterator can be incremented until it reaches past the end point. When it does, the
iterator will become invalid. An invalid iterator will test false. The IsAtEnd method
can be used instead to test for this condition. It is also possible to compare two iterators
for equality (i.e. to compare against an end iterator).
Dereferencing the iterator yields the offset to the current pixel.
Satisfies all the requirements for a mutable ForwardIterator.
Constructors, destructors, assignment and conversion operators
- BresenhamLineIterator() defaulted
- Default constructor yields an invalid iterator that cannot be dereferenced, and is equivalent to an end iterator
- BresenhamLineIterator(dip::IntegerArray strides, dip::UnsignedArray start, dip::UnsignedArray const& end)
- To construct a useful iterator, provide image strides, and coordinates of the start and end pixels
- BresenhamLineIterator(dip::IntegerArray strides, dip::FloatArray stepSize, dip::UnsignedArray start, dip::uint length)
- To construct a useful iterator, provide image strides, a step size, a start position, and a length
Aliases
- using iterator_category = std::forward_iterator_tag
- Iterator category
- using value_type = dip::sint
- The type of an offset
- using reference = dip::BresenhamLineIterator::value_type const&
- The type of a reference to an offset
- using pointer = dip::BresenhamLineIterator::value_type const*
- The type of a pointer an offset
Functions
- void swap(dip::BresenhamLineIterator& other) noexcept
- Swap
- auto IsAtEnd() const -> bool
- Test to see if the iterator reached past the last pixel
- auto Coordinates() const -> dip::UnsignedArray const&
- Return the current coordinates in the image
- auto Offset() const -> dip::sint
- Return the current offset
- auto Length() const -> dip::uint
- Return the number of pixels left on the line after the current one
Operators
- auto operator*() const -> dip::sint
- Dereference
- auto operator++() -> dip::BresenhamLineIterator&
- Pre-increment
- auto operator++(int ) -> dip::BresenhamLineIterator
- Post-increment
- auto operator==(dip::BresenhamLineIterator const& other) const -> bool
- Equality comparison (is equal if coordinates are identical)
- auto operator!=(dip::BresenhamLineIterator const& other) const -> bool
- Inequality comparison (is unequal if coordinates are not identical)
- auto operator bool() const -> bool explicit
- Test to see if the iterator is still pointing at a pixel
Variables
- static dip::dfloat const epsilon constexpr
- Tolerance used to avoid errors caused by rounding.
- static dip::dfloat const delta constexpr
- A distance of almost one pixel.