Maintainer | mail@joachim-breitner.de |
---|---|

Safe Haskell | None |

A method for laying out diagrams using a circle packing algorithm. For details on the algorithm, see Optimisation.CirclePacking in the module circle-packing.

Here is an example:

import Optimisation.CirclePacking colorize = zipWith fc $ cycle [red,blue,yellow,magenta,cyan,bisque,firebrick,indigo] objects = colorize $ [ circle r | r <- [0.1,0.2..1.6] ] ++ [ hexagon r | r <- [0.1,0.2..0.7] ] ++ [ decagon r | r <- [0.1,0.2..0.7] ] -- Just a approximation, diagram objects do not have an exact radius radiusApproximation o = maximum [ radius (e (CircleFrac alpha)) o | alpha <- [0,0.1..1.0]] circlePackingExample = position $ map (\(o,(x,y)) -> (p2 (x,y),o)) $ packCircles radiusApproximation objects

- renderCirclePacking :: Monoid' m => RadiusFunction b m -> [QDiagram b R2 m] -> QDiagram b R2 m
- createCirclePacking :: Monoid' m => (a -> Double) -> (a -> QDiagram b R2 m) -> [a] -> QDiagram b R2 m
- type RadiusFunction b m = QDiagram b R2 m -> Double
- approxRadius :: Int -> RadiusFunction b m
- circleRadius :: RadiusFunction b m

# Documentation

renderCirclePacking :: Monoid' m => RadiusFunction b m -> [QDiagram b R2 m] -> QDiagram b R2 mSource

Combines the passed objects, whose radius is estimated using the given
`RadiusFunction`

, so that they do not overlap (according to the radius
function) and otherwise form, as far as possible, a tight circle.

createCirclePacking :: Monoid' m => (a -> Double) -> (a -> QDiagram b R2 m) -> [a] -> QDiagram b R2 mSource

More general version of `renderCirclePacking`

. You can use this if you
have more information available in the values of type `a`

that allows you to
calculate the radius better (or even exactly).

type RadiusFunction b m = QDiagram b R2 m -> DoubleSource

The type of radius-estimating functions for Diagrams such as
`approxRadius`

and `circleRadius`

. When you can calculate the radius better,
but not any more once you converted your data to a diagram, use `createCirclePacking`

.

approxRadius :: Int -> RadiusFunction b mSource

A safe approximation. Calculates the outer radius of the smallest axis-aligned polygon with the given number of edges that contains the object. A parameter of 4 up to 8 should be sufficient for most applications.

circleRadius :: RadiusFunction b mSource

An unsafe approximation. This is the radius of the largest circle that fits in the rectangular bounding box of the object, so it may be too small. It is, however, exact for circles, and there is no function that is safe for all diagrams and exact for circles.