Safe Haskell	None
Language	Haskell98

Graphics.Gloss.Data.ViewState

Synopsis

Documentation

data Command Source

The commands suported by the view controller.

Constructors

CRestore
CTranslate
CRotate
CBumpZoomOut
CBumpZoomIn
CBumpLeft
CBumpRight
CBumpUp
CBumpDown
CBumpClockwise
CBumpCClockwise

Instances

Eq Command
Ord Command
Show Command

type CommandConfig = [(Command, [(Key, Maybe Modifiers)])] Source

defaultCommandConfig :: CommandConfig Source

The default commands. Left click pans, wheel zooms, right click rotates, "r" key resets.

data ViewState Source

State for controlling the viewport. These are used by the viewport control component.

Constructors

ViewState

Fields

viewStateCommands :: !(Map Command [(Key, Maybe Modifiers)]): The command list for the viewport controller. These can be safely overwridden at any time by deleting or adding entries to the list. Entries at the front of the list take precedence.
viewStateScaleStep :: !Float: How much to scale the world by for each step of the mouse wheel.
viewStateRotateFactor :: !Float: How many degrees to rotate the world by for each pixel of x motion.
viewStateTranslateMark :: !(Maybe (Float, Float)): During viewport translation, where the mouse was clicked on the window.
viewStateRotateMark :: !(Maybe (Float, Float)): During viewport rotation, where the mouse was clicked on the window
viewStateViewPort :: ViewPort

data ViewPort Source

The ViewPort represents the global transformation applied to the displayed picture. When the user pans, zooms, or rotates the display then this changes the ViewPort.

Constructors

ViewPort
Fields viewPortTranslate :: !(Float, Float) Global translation. viewPortRotate :: !Float Global rotation (in degrees). viewPortScale :: !Float Global scaling (of both x and y coordinates).

viewStateInit :: ViewState Source

The initial view state.

viewStateInitWithConfig :: CommandConfig -> ViewState Source

Initial view state, with user defined config.

updateViewStateWithEvent :: Event -> ViewState -> ViewState Source

Apply an event to a ViewState.

updateViewStateWithEventMaybe :: Event -> ViewState -> Maybe ViewState Source

Like updateViewStateWithEvent, but returns Nothing if no update was needed.

applyViewPortToPicture :: ViewPort -> Picture -> Picture Source

Translates, rotates, and scales an image according to the ViewPort.

invertViewPort :: ViewPort -> Point -> Point Source

Takes a point using screen coordinates, and uses the ViewPort to convert it to Picture coordinates. This is the inverse of applyViewPortToPicture for points.