| Copyright | (c) 2013 diagrams-lib team (see LICENSE) |
|---|---|
| License | BSD-style (see LICENSE) |
| Maintainer | diagrams-discuss@googlegroups.com |
| Safe Haskell | Safe-Inferred |
| Language | Haskell2010 |
Diagrams.Parametric
Description
Type classes for things which are parameterized in some way, e.g. segments and trails.
Synopsis
- stdTolerance :: Fractional a => a
- type family Codomain p :: Type -> Type
- class Parametric p where
- class DomainBounds p where
- domainLower :: p -> N p
- domainUpper :: p -> N p
- domainBounds :: DomainBounds p => p -> (N p, N p)
- class (Parametric p, DomainBounds p) => EndValues p where
- class DomainBounds p => Sectionable p where
- splitAtParam :: p -> N p -> (p, p)
- section :: p -> N p -> N p -> p
- reverseDomain :: p -> p
- class Parametric p => HasArcLength p where
- arcLengthBounded :: N p -> p -> Interval (N p)
- arcLength :: N p -> p -> N p
- stdArcLength :: p -> N p
- arcLengthToParam :: N p -> p -> N p -> N p
- stdArcLengthToParam :: p -> N p -> N p
Documentation
stdTolerance :: Fractional a => a Source #
The standard tolerance used by std... functions (like
stdArcLength and stdArcLengthToParam, currently set at
1e-6.
type family Codomain p :: Type -> Type Source #
Codomain of parametric classes. This is usually either (V p), for relative
vector results, or (Point (V p)), for functions with absolute coordinates.
Instances
| type Codomain (BernsteinPoly n) Source # | |
Defined in Diagrams.TwoD.Segment.Bernstein | |
| type Codomain (Located a) Source # | |
Defined in Diagrams.Located | |
| type Codomain (Tangent t) Source # | |
Defined in Diagrams.Tangent | |
| type Codomain (GetSegment t) Source # | |
Defined in Diagrams.Trail | |
| type Codomain (FixedSegment v n) Source # | |
Defined in Diagrams.Segment | |
| type Codomain (Trail v n) Source # | |
Defined in Diagrams.Trail | |
| type Codomain (SegTree v n) Source # | |
Defined in Diagrams.Trail | |
| type Codomain (Segment Closed v n) Source # | |
Defined in Diagrams.Segment | |
| type Codomain (Trail' l v n) Source # | |
Defined in Diagrams.Trail | |
class Parametric p where Source #
Type class for parametric functions.
Methods
Instances
class DomainBounds p where Source #
Type class for parametric functions with a bounded domain. The
default bounds are [0,1].
Note that this domain indicates the main "interesting" portion of the function. It must be defined within this range, but for some instances may still have sensible values outside.
Minimal complete definition
Nothing
Methods
domainLower :: p -> N p Source #
domainLower defaults to being constantly 0 (for vector spaces with
numeric scalars).
domainUpper :: p -> N p Source #
domainUpper defaults to being constantly 1 (for vector spaces
with numeric scalars).
Instances
domainBounds :: DomainBounds p => p -> (N p, N p) Source #
Return the lower and upper bounds of a parametric domain together as a pair.
class (Parametric p, DomainBounds p) => EndValues p where Source #
Type class for querying the values of a parametric object at the ends of its domain.
Minimal complete definition
Nothing
Methods
atStart :: p -> Codomain p (N p) Source #
atStart is the value at the start of the domain. That is,
atStart x = x `atParam` domainLower x
This is the default implementation, but some representations will have a more efficient and/or precise implementation.
atEnd :: p -> Codomain p (N p) Source #
atEnd is the value at the end of the domain. That is,
atEnd x = x `atParam` domainUpper x
This is the default implementation, but some representations will have a more efficient and/or precise implementation.
Instances
class DomainBounds p => Sectionable p where Source #
Type class for parametric objects which can be split into subobjects.
Minimal definition: Either splitAtParam or section,
plus reverseDomain.
Minimal complete definition
Methods
splitAtParam :: p -> N p -> (p, p) Source #
splitAtParam splits an object p into two new objects
(l,r) at the parameter t, where l corresponds to the
portion of p for parameter values from 0 to t and r for
to that from t to 1. The following property should hold:
prop_splitAtParam f t u =
| u < t = atParam f u == atParam l (u / t)
| otherwise = atParam f u == atParam f t ??? atParam l ((u - t) / (domainUpper f - t))
where (l,r) = splitAtParam f t
where (???) = (^+^) if the codomain is a vector type, or
const flip if the codomain is a point type. Stated more
intuitively, all this is to say that the parameterization
scales linearly with splitting.
splitAtParam can also be used with parameters outside the
range of the domain. For example, using the parameter 2 with
a path (where the domain is the default [0,1]) gives two
result paths where the first is the original path extended to
the parameter 2, and the second result path travels backwards
from the end of the first to the end of the original path.
section :: p -> N p -> N p -> p Source #
Extract a particular section of the domain, linearly reparameterized to the same domain as the original. Should satisfy the property:
prop_section x l u t =
let s = section x l u
in domainBounds x == domainBounds x
&& (x `atParam` lerp l u t) == (s `atParam` t)That is, the section should have the same domain as the original, and the reparameterization should be linear.
reverseDomain :: p -> p Source #
Flip the parameterization on the domain.
Instances
| Fractional n => Sectionable (BernsteinPoly n) Source # | |
Defined in Diagrams.TwoD.Segment.Bernstein Methods splitAtParam :: BernsteinPoly n -> N (BernsteinPoly n) -> (BernsteinPoly n, BernsteinPoly n) Source # section :: BernsteinPoly n -> N (BernsteinPoly n) -> N (BernsteinPoly n) -> BernsteinPoly n Source # reverseDomain :: BernsteinPoly n -> BernsteinPoly n Source # | |
| (InSpace v n a, Fractional n, Parametric a, Sectionable a, Codomain a ~ v) => Sectionable (Located a) Source # | |
| (Additive v, Fractional n) => Sectionable (FixedSegment v n) Source # | |
Defined in Diagrams.Segment Methods splitAtParam :: FixedSegment v n -> N (FixedSegment v n) -> (FixedSegment v n, FixedSegment v n) Source # section :: FixedSegment v n -> N (FixedSegment v n) -> N (FixedSegment v n) -> FixedSegment v n Source # reverseDomain :: FixedSegment v n -> FixedSegment v n Source # | |
| (Metric v, OrderedField n, Real n) => Sectionable (Trail v n) Source # | Note that there is no |
| (Metric v, OrderedField n, Real n) => Sectionable (SegTree v n) Source # | |
| (Additive v, Fractional n) => Sectionable (Segment Closed v n) Source # | |
Defined in Diagrams.Segment | |
| (Metric v, OrderedField n, Real n) => Sectionable (Trail' Line v n) Source # | |
class Parametric p => HasArcLength p where Source #
Type class for parametric things with a notion of arc length.
Minimal complete definition
Methods
arcLengthBounded :: N p -> p -> Interval (N p) Source #
arcLengthBounded eps x approximates the arc length of x.
The true arc length is guaranteed to lie within the interval
returned, which will have a size of at most eps.
arcLength :: N p -> p -> N p Source #
arcLength eps s approximates the arc length of x up to the
accuracy eps (plus or minus).
stdArcLength :: p -> N p Source #
Approximate the arc length up to a standard accuracy of
stdTolerance (1e-6).
default stdArcLength :: Fractional (N p) => p -> N p Source #
arcLengthToParam :: N p -> p -> N p -> N p Source #
arcLengthToParam eps s ll, measured from the start of the domain, to a parameter on
the object s. The true arc length at the parameter returned
is guaranteed to be within eps of the requested arc length.
This should work for any arc length, and may return any parameter value (not just parameters in the domain).
stdArcLengthToParam :: p -> N p -> N p Source #
A simple interface to convert arc length to a parameter,
guaranteed to be accurate within stdTolerance, or 1e-6.
default stdArcLengthToParam :: Fractional (N p) => p -> N p -> N p Source #