312 lines
9.6 KiB
Elm
312 lines
9.6 KiB
Elm
module Graphics.Element where
|
|
{-| Graphical elements that snap together to build complex widgets and layouts.
|
|
Each Element is a rectangle with a known width and height, making them easy to
|
|
combine and position.
|
|
|
|
# Images
|
|
@docs image, fittedImage, croppedImage, tiledImage
|
|
|
|
# Styling
|
|
@docs width, height, size, color, opacity, link, tag
|
|
|
|
# Inspection
|
|
@docs widthOf, heightOf, sizeOf
|
|
|
|
# Layout
|
|
@docs flow, up, down, left, right, inward, outward
|
|
|
|
## Layout Aliases
|
|
There are also some convenience functions for working
|
|
with `flow` in specific cases:
|
|
|
|
@docs layers, above, below, beside
|
|
|
|
# Positioning
|
|
@docs empty, spacer, container
|
|
|
|
## Specific Positions
|
|
|
|
To create a `Position` you can use any of the built-in positions
|
|
which cover nine common positions.
|
|
@docs middle, midTop, midBottom, midLeft, midRight, topLeft, topRight,
|
|
bottomLeft, bottomRight
|
|
|
|
If you need more precision, you can create custom positions.
|
|
|
|
@docs absolute, relative, middleAt, midTopAt, midBottomAt, midLeftAt,
|
|
midRightAt, topLeftAt, topRightAt, bottomLeftAt, bottomRightAt
|
|
-}
|
|
|
|
import open Basics
|
|
import Native.Utils
|
|
import JavaScript as JS
|
|
import JavaScript (JSString)
|
|
import List as List
|
|
import open Color
|
|
import Maybe (Maybe, Just, Nothing)
|
|
|
|
type Properties = {
|
|
id : Int,
|
|
width : Int,
|
|
height : Int,
|
|
opacity : Float,
|
|
color : Maybe Color,
|
|
href : JSString,
|
|
tag : JSString,
|
|
hover : ()
|
|
}
|
|
|
|
type Element = { props : Properties, element : ElementPrim }
|
|
|
|
{-| An Element that takes up no space. Good for things that appear conditionally:
|
|
|
|
flow down [ img1, if showMore then img2 else empty ]
|
|
-}
|
|
empty : Element
|
|
empty = spacer 0 0
|
|
|
|
{-| Get the width of an Element -}
|
|
widthOf : Element -> Int
|
|
widthOf e = e.props.width
|
|
|
|
{-| Get the height of an Element -}
|
|
heightOf : Element -> Int
|
|
heightOf e = e.props.height
|
|
|
|
{-| Get the width and height of an Element -}
|
|
sizeOf : Element -> (Int,Int)
|
|
sizeOf e = (e.props.width, e.props.height)
|
|
|
|
{-| Create an `Element` with a given width. -}
|
|
width : Int -> Element -> Element
|
|
width nw e =
|
|
let p = e.props
|
|
props = case e.element of
|
|
Image _ w h _ -> {p| height <- round (toFloat h / toFloat w * toFloat nw) }
|
|
RawHtml -> {p| height <- snd (Native.Utils.htmlHeight nw e.element) }
|
|
_ -> p
|
|
in { element=e.element, props={ props | width <- nw } }
|
|
|
|
{-| Create an `Element` with a given height. -}
|
|
height : Int -> Element -> Element
|
|
height nh e =
|
|
let p = e.props
|
|
props = case e.element of
|
|
Image _ w h _ -> {p| width <- round (toFloat w / toFloat h * toFloat nh) }
|
|
_ -> p
|
|
in { element=e.element, props={ p | height <- nh} }
|
|
|
|
{-| Create an `Element` with a new width and height. -}
|
|
size : Int -> Int -> Element -> Element
|
|
size w h e = height h (width w e)
|
|
|
|
{-| Create an `Element` with a given opacity. Opacity is a number between 0 and 1
|
|
where 0 means totally clear.
|
|
-}
|
|
opacity : Float -> Element -> Element
|
|
opacity o e = let p = e.props in { element=e.element, props={p| opacity <- o} }
|
|
|
|
{-| Create an `Element` with a given background color. -}
|
|
color : Color -> Element -> Element
|
|
color c e = let p = e.props in
|
|
{ element = e.element
|
|
, props = { p | color <- Just c}
|
|
}
|
|
|
|
{-| Create an `Element` with a tag. This lets you link directly to it.
|
|
The element `(tag "all-about-badgers" thirdParagraph)` can be reached
|
|
with a link like this: `/facts-about-animals.elm#all-about-badgers`
|
|
-}
|
|
tag : String -> Element -> Element
|
|
tag name e = let p = e.props in
|
|
{ element=e.element, props={p | tag <- JS.fromString name} }
|
|
|
|
{-| Create an `Element` that is a hyper-link. -}
|
|
link : String -> Element -> Element
|
|
link href e = let p = e.props in
|
|
{ element=e.element, props={p | href <- JS.fromString href} }
|
|
|
|
emptyStr = JS.fromString ""
|
|
newElement w h e =
|
|
{ props = Properties (Native.Utils.guid ()) w h 1 Nothing emptyStr emptyStr (), element = e }
|
|
|
|
data ElementPrim
|
|
= Image ImageStyle Int Int JSString
|
|
| Container Position Element
|
|
| Flow Direction [Element]
|
|
| Spacer
|
|
| RawHtml
|
|
| Custom -- for custom Elements implemented in JS, see collage for example
|
|
|
|
data ImageStyle = Plain | Fitted | Cropped (Int,Int) | Tiled
|
|
|
|
{-| Create an image given a width, height, and image source. -}
|
|
image : Int -> Int -> String -> Element
|
|
image w h src = newElement w h (Image Plain w h (JS.fromString src))
|
|
|
|
{-| Create a fitted image given a width, height, and image source.
|
|
This will crop the picture to best fill the given dimensions.
|
|
-}
|
|
fittedImage : Int -> Int -> String -> Element
|
|
fittedImage w h src = newElement w h (Image Fitted w h (JS.fromString src))
|
|
|
|
{-| Create a cropped image. Take a rectangle out of the picture starting
|
|
at the given top left coordinate. If you have a 140-by-140 image,
|
|
the following will cut a 100-by-100 square out of the middle of it.
|
|
|
|
croppedImage (20,20) 100 100 "yogi.jpg"
|
|
-}
|
|
croppedImage : (Int,Int) -> Int -> Int -> String -> Element
|
|
croppedImage pos w h src =
|
|
newElement w h (Image (Cropped pos) w h (JS.fromString src))
|
|
|
|
tiledImage : Int -> Int -> String -> Element
|
|
tiledImage w h src =
|
|
newElement w h (Image Tiled w h (JS.fromString src))
|
|
|
|
data Three = P | Z | N
|
|
data Pos = Absolute Int | Relative Float
|
|
type Position = { horizontal : Three, vertical : Three, x : Pos, y : Pos }
|
|
|
|
{-| Put an element in a container. This lets you position the element really
|
|
easily, and there are tons of ways to set the `Position`.
|
|
To center `element` exactly in a 300-by-300 square you would say:
|
|
|
|
container 300 300 middle element
|
|
|
|
By setting the color of the container, you can create borders.
|
|
-}
|
|
container : Int -> Int -> Position -> Element -> Element
|
|
container w h pos e = newElement w h (Container pos e)
|
|
|
|
{-| Create an empty box. This is useful for getting your spacing right and
|
|
for making borders.
|
|
-}
|
|
spacer : Int -> Int -> Element
|
|
spacer w h = newElement w h Spacer
|
|
|
|
data Direction = DUp | DDown | DLeft | DRight | DIn | DOut
|
|
|
|
{-| Have a list of elements flow in a particular direction.
|
|
The `Direction` starts from the first element in the list.
|
|
|
|
flow right [a,b,c]
|
|
|
|
+---+---+---+
|
|
| a | b | c |
|
|
+---+---+---+
|
|
-}
|
|
flow : Direction -> [Element] -> Element
|
|
flow dir es =
|
|
let ws = List.map widthOf es
|
|
hs = List.map heightOf es
|
|
newFlow w h = newElement w h (Flow dir es)
|
|
in
|
|
if es == [] then empty else
|
|
case dir of
|
|
DUp -> newFlow (List.maximum ws) (List.sum hs)
|
|
DDown -> newFlow (List.maximum ws) (List.sum hs)
|
|
DLeft -> newFlow (List.sum ws) (List.maximum hs)
|
|
DRight -> newFlow (List.sum ws) (List.maximum hs)
|
|
DIn -> newFlow (List.maximum ws) (List.maximum hs)
|
|
DOut -> newFlow (List.maximum ws) (List.maximum hs)
|
|
|
|
{-| Stack elements vertically.
|
|
To put `a` above `b` you would say: ``a `above` b``
|
|
-}
|
|
above : Element -> Element -> Element
|
|
above hi lo =
|
|
newElement (max (widthOf hi) (widthOf lo))
|
|
(heightOf hi + heightOf lo)
|
|
(Flow DDown [hi,lo])
|
|
|
|
{-| Stack elements vertically.
|
|
To put `a` below `b` you would say: ``a `below` b``
|
|
-}
|
|
below : Element -> Element -> Element
|
|
below lo hi =
|
|
newElement (max (widthOf hi) (widthOf lo))
|
|
(heightOf hi + heightOf lo)
|
|
(Flow DDown [hi,lo])
|
|
|
|
{-| Put elements beside each other horizontally.
|
|
To put `a` beside `b` you would say: ``a `beside` b``
|
|
-}
|
|
beside : Element -> Element -> Element
|
|
beside lft rht =
|
|
newElement (widthOf lft + widthOf rht)
|
|
(max (heightOf lft) (heightOf rht))
|
|
(Flow right [lft,rht])
|
|
|
|
{-| Layer elements on top of each other, starting from the bottom:
|
|
`layers == flow outward`
|
|
-}
|
|
layers : [Element] -> Element
|
|
layers es =
|
|
let ws = List.map widthOf es
|
|
hs = List.map heightOf es
|
|
in newElement (List.maximum ws) (List.maximum hs) (Flow DOut es)
|
|
|
|
|
|
-- Repetitive things --
|
|
|
|
absolute : Int -> Pos
|
|
absolute = Absolute
|
|
relative : Float -> Pos
|
|
relative = Relative
|
|
|
|
middle : Position
|
|
middle = { horizontal=Z, vertical=Z, x=Relative 0.5, y=Relative 0.5 }
|
|
topLeft : Position
|
|
topLeft = { horizontal=N, vertical=P, x=Absolute 0, y=Absolute 0 }
|
|
topRight : Position
|
|
topRight = { topLeft | horizontal <- P }
|
|
bottomLeft : Position
|
|
bottomLeft = { topLeft | vertical <- N }
|
|
bottomRight : Position
|
|
bottomRight = { bottomLeft | horizontal <- P }
|
|
midLeft : Position
|
|
midLeft = { middle | horizontal <- N, x <- Absolute 0 }
|
|
midRight : Position
|
|
midRight = { midLeft | horizontal <- P }
|
|
midTop : Position
|
|
midTop = { middle | vertical <- P, y <- Absolute 0 }
|
|
midBottom : Position
|
|
midBottom = { midTop | vertical <- N }
|
|
|
|
middleAt : Pos -> Pos -> Position
|
|
middleAt x y = { horizontal = Z, vertical = Z, x = x, y = y }
|
|
topLeftAt : Pos -> Pos -> Position
|
|
topLeftAt x y = { horizontal = N, vertical = P, x = x, y = y }
|
|
topRightAt : Pos -> Pos -> Position
|
|
topRightAt x y = { horizontal = P, vertical = P, x = x, y = y }
|
|
bottomLeftAt : Pos -> Pos -> Position
|
|
bottomLeftAt x y = { horizontal = N, vertical = N, x = x, y = y }
|
|
bottomRightAt : Pos -> Pos -> Position
|
|
bottomRightAt x y = { horizontal = P, vertical = N, x = x, y = y }
|
|
midLeftAt : Pos -> Pos -> Position
|
|
midLeftAt x y = { horizontal = N, vertical = Z, x = x, y = y }
|
|
midRightAt : Pos -> Pos -> Position
|
|
midRightAt x y = { horizontal = P, vertical = Z, x = x, y = y }
|
|
midTopAt : Pos -> Pos -> Position
|
|
midTopAt x y = { horizontal = Z, vertical = P, x = x, y = y }
|
|
midBottomAt : Pos -> Pos -> Position
|
|
midBottomAt x y = { horizontal = Z, vertical = N, x = x, y = y }
|
|
|
|
up : Direction
|
|
up = DUp
|
|
|
|
down : Direction
|
|
down = DDown
|
|
|
|
left : Direction
|
|
left = DLeft
|
|
|
|
right : Direction
|
|
right = DRight
|
|
|
|
inward : Direction
|
|
inward = DIn
|
|
|
|
outward : Direction
|
|
outward = DOut
|