NanoVG.Internal

Documentation

newtype FileName

Newtype to avoid accidental use of strings

Constructors

FileName

Fields

• unwrapFileName :: Text

newtype Image

Newtype to avoid accidental use of ints

Constructors

Image

Fields

• imageHandle :: CInt

Instances

Eq Image

Methods

(==) :: Image -> Image -> Bool

(/=) :: Image -> Image -> Bool

Ord Image

Methods

compare :: Image -> Image -> Ordering

(<) :: Image -> Image -> Bool

(<=) :: Image -> Image -> Bool

(>) :: Image -> Image -> Bool

(>=) :: Image -> Image -> Bool

max :: Image -> Image -> Image

min :: Image -> Image -> Image

Read Image

Methods

readsPrec :: Int -> ReadS Image

readList :: ReadS [Image]

readPrec :: ReadPrec Image

readListPrec :: ReadPrec [Image]

Show Image

Methods

showsPrec :: Int -> Image -> ShowS

show :: Image -> String

showList :: [Image] -> ShowS

newtype Context

Opaque context that needs to be passed around

Constructors

Context (Ptr Context)

newtype Transformation

Affine matrix

[sx kx tx]
[ky sy ty]
[ 0  0  1]

Constructors

Transformation (M23 CFloat)

Instances

Eq Transformation

Methods

(==) :: Transformation -> Transformation -> Bool

(/=) :: Transformation -> Transformation -> Bool

Ord Transformation

Methods

compare :: Transformation -> Transformation -> Ordering

(<) :: Transformation -> Transformation -> Bool

(<=) :: Transformation -> Transformation -> Bool

(>) :: Transformation -> Transformation -> Bool

(>=) :: Transformation -> Transformation -> Bool

max :: Transformation -> Transformation -> Transformation

min :: Transformation -> Transformation -> Transformation

Read Transformation

Methods

readsPrec :: Int -> ReadS Transformation

readList :: ReadS [Transformation]

readPrec :: ReadPrec Transformation

readListPrec :: ReadPrec [Transformation]

Show Transformation

Methods

showsPrec :: Int -> Transformation -> ShowS

show :: Transformation -> String

showList :: [Transformation] -> ShowS

Storable Transformation

Methods

sizeOf :: Transformation -> Int

alignment :: Transformation -> Int

peekElemOff :: Ptr Transformation -> Int -> IO Transformation

pokeElemOff :: Ptr Transformation -> Int -> Transformation -> IO ()

peekByteOff :: Ptr b -> Int -> IO Transformation

pokeByteOff :: Ptr b -> Int -> Transformation -> IO ()

peek :: Ptr Transformation -> IO Transformation

poke :: Ptr Transformation -> Transformation -> IO ()

newtype Extent

Constructors

Extent (V2 CFloat)

Instances

Eq Extent

Methods

(==) :: Extent -> Extent -> Bool

(/=) :: Extent -> Extent -> Bool

Ord Extent

Methods

compare :: Extent -> Extent -> Ordering

(<) :: Extent -> Extent -> Bool

(<=) :: Extent -> Extent -> Bool

(>) :: Extent -> Extent -> Bool

(>=) :: Extent -> Extent -> Bool

max :: Extent -> Extent -> Extent

min :: Extent -> Extent -> Extent

Read Extent

Methods

readsPrec :: Int -> ReadS Extent

readList :: ReadS [Extent]

readPrec :: ReadPrec Extent

readListPrec :: ReadPrec [Extent]

Show Extent

Methods

showsPrec :: Int -> Extent -> ShowS

show :: Extent -> String

showList :: [Extent] -> ShowS

Storable Extent

Methods

sizeOf :: Extent -> Int

alignment :: Extent -> Int

peekElemOff :: Ptr Extent -> Int -> IO Extent

pokeElemOff :: Ptr Extent -> Int -> Extent -> IO ()

peekByteOff :: Ptr b -> Int -> IO Extent

pokeByteOff :: Ptr b -> Int -> Extent -> IO ()

peek :: Ptr Extent -> IO Extent

poke :: Ptr Extent -> Extent -> IO ()

data Color

rgba

Constructors

Color !CFloat !CFloat !CFloat !CFloat

Instances

Eq Color

Methods

(==) :: Color -> Color -> Bool

(/=) :: Color -> Color -> Bool

Ord Color

Methods

compare :: Color -> Color -> Ordering

(<) :: Color -> Color -> Bool

(<=) :: Color -> Color -> Bool

(>) :: Color -> Color -> Bool

(>=) :: Color -> Color -> Bool

max :: Color -> Color -> Color

min :: Color -> Color -> Color

Read Color

Methods

readsPrec :: Int -> ReadS Color

readList :: ReadS [Color]

readPrec :: ReadPrec Color

readListPrec :: ReadPrec [Color]

Show Color

Methods

showsPrec :: Int -> Color -> ShowS

show :: Color -> String

showList :: [Color] -> ShowS

Storable Color

Methods

sizeOf :: Color -> Int

alignment :: Color -> Int

peekElemOff :: Ptr Color -> Int -> IO Color

pokeElemOff :: Ptr Color -> Int -> Color -> IO ()

peekByteOff :: Ptr b -> Int -> IO Color

pokeByteOff :: Ptr b -> Int -> Color -> IO ()

peek :: Ptr Color -> IO Color

poke :: Ptr Color -> Color -> IO ()

data Paint

Constructors

Paint

Fields

• xform :: Transformation
• extent :: Extent
• radius :: !CFloat
• feather :: !CFloat
• innerColor :: !Color
• outerColor :: !Color
• image :: !Image

Instances

Eq Paint

Methods

(==) :: Paint -> Paint -> Bool

(/=) :: Paint -> Paint -> Bool

Ord Paint

Methods

compare :: Paint -> Paint -> Ordering

(<) :: Paint -> Paint -> Bool

(<=) :: Paint -> Paint -> Bool

(>) :: Paint -> Paint -> Bool

(>=) :: Paint -> Paint -> Bool

max :: Paint -> Paint -> Paint

min :: Paint -> Paint -> Paint

Read Paint

Methods

readsPrec :: Int -> ReadS Paint

readList :: ReadS [Paint]

readPrec :: ReadPrec Paint

readListPrec :: ReadPrec [Paint]

Show Paint

Methods

showsPrec :: Int -> Paint -> ShowS

show :: Paint -> String

showList :: [Paint] -> ShowS

Storable Paint

Methods

sizeOf :: Paint -> Int

alignment :: Paint -> Int

peekElemOff :: Ptr Paint -> Int -> IO Paint

pokeElemOff :: Ptr Paint -> Int -> Paint -> IO ()

peekByteOff :: Ptr b -> Int -> IO Paint

pokeByteOff :: Ptr b -> Int -> Paint -> IO ()

peek :: Ptr Paint -> IO Paint

poke :: Ptr Paint -> Paint -> IO ()

data Solidity

Constructors

Solid

Hole

Instances

Enum Solidity

Methods

succ :: Solidity -> Solidity

pred :: Solidity -> Solidity

toEnum :: Int -> Solidity

fromEnum :: Solidity -> Int

enumFrom :: Solidity -> [Solidity]

enumFromThen :: Solidity -> Solidity -> [Solidity]

enumFromTo :: Solidity -> Solidity -> [Solidity]

enumFromThenTo :: Solidity -> Solidity -> Solidity -> [Solidity]

Eq Solidity

Methods

(==) :: Solidity -> Solidity -> Bool

(/=) :: Solidity -> Solidity -> Bool

Ord Solidity

Methods

compare :: Solidity -> Solidity -> Ordering

(<) :: Solidity -> Solidity -> Bool

(<=) :: Solidity -> Solidity -> Bool

(>) :: Solidity -> Solidity -> Bool

(>=) :: Solidity -> Solidity -> Bool

max :: Solidity -> Solidity -> Solidity

min :: Solidity -> Solidity -> Solidity

Read Solidity

Methods

readsPrec :: Int -> ReadS Solidity

readList :: ReadS [Solidity]

readPrec :: ReadPrec Solidity

readListPrec :: ReadPrec [Solidity]

Show Solidity

Methods

showsPrec :: Int -> Solidity -> ShowS

show :: Solidity -> String

showList :: [Solidity] -> ShowS

data LineCap

Constructors

Butt

Round

Square

Bevel

Miter

Instances

Enum LineCap

Methods

succ :: LineCap -> LineCap

pred :: LineCap -> LineCap

toEnum :: Int -> LineCap

fromEnum :: LineCap -> Int

enumFrom :: LineCap -> [LineCap]

enumFromThen :: LineCap -> LineCap -> [LineCap]

enumFromTo :: LineCap -> LineCap -> [LineCap]

enumFromThenTo :: LineCap -> LineCap -> LineCap -> [LineCap]

Eq LineCap

Methods

(==) :: LineCap -> LineCap -> Bool

(/=) :: LineCap -> LineCap -> Bool

Ord LineCap

Methods

compare :: LineCap -> LineCap -> Ordering

(<) :: LineCap -> LineCap -> Bool

(<=) :: LineCap -> LineCap -> Bool

(>) :: LineCap -> LineCap -> Bool

(>=) :: LineCap -> LineCap -> Bool

max :: LineCap -> LineCap -> LineCap

min :: LineCap -> LineCap -> LineCap

Read LineCap

Methods

readsPrec :: Int -> ReadS LineCap

readList :: ReadS [LineCap]

readPrec :: ReadPrec LineCap

readListPrec :: ReadPrec [LineCap]

Show LineCap

Methods

showsPrec :: Int -> LineCap -> ShowS

show :: LineCap -> String

showList :: [LineCap] -> ShowS

data Winding

Constructors

CCW

CW

Instances

Enum Winding

Methods

succ :: Winding -> Winding

pred :: Winding -> Winding

toEnum :: Int -> Winding

fromEnum :: Winding -> Int

enumFrom :: Winding -> [Winding]

enumFromThen :: Winding -> Winding -> [Winding]

enumFromTo :: Winding -> Winding -> [Winding]

enumFromThenTo :: Winding -> Winding -> Winding -> [Winding]

Eq Winding

Methods

(==) :: Winding -> Winding -> Bool

(/=) :: Winding -> Winding -> Bool

Ord Winding

Methods

compare :: Winding -> Winding -> Ordering

(<) :: Winding -> Winding -> Bool

(<=) :: Winding -> Winding -> Bool

(>) :: Winding -> Winding -> Bool

(>=) :: Winding -> Winding -> Bool

max :: Winding -> Winding -> Winding

min :: Winding -> Winding -> Winding

Read Winding

Methods

readsPrec :: Int -> ReadS Winding

readList :: ReadS [Winding]

readPrec :: ReadPrec Winding

readListPrec :: ReadPrec [Winding]

Show Winding

Methods

showsPrec :: Int -> Winding -> ShowS

show :: Winding -> String

showList :: [Winding] -> ShowS

beginFrame :: Context -> CInt -> CInt -> Float -> IO ()

Begin drawing a new frame

Calls to nanovg drawing API should be wrapped in beginFrame & endFrame.

beginFrame defines the size of the window to render to in relation currently set viewport (i.e. glViewport on GL backends). Device pixel ration allows to control the rendering on Hi-DPI devices.

For example, GLFW returns two dimension for an opened window: window size and frame buffer size. In that case you would set windowWidth/Height to the window size devicePixelRatio to: frameBufferWidth / windowWidth.

cancelFrame :: Context -> IO ()

Cancels drawing the current frame.

endFrame :: Context -> IO ()

Ends drawing flushing remaining render state.

Color utils

rgb :: CUChar -> CUChar -> CUChar -> Color

Returns a color value from red, green, blue values. Alpha will be set to 255 (1.0f).

rgbf :: CFloat -> CFloat -> CFloat -> Color

Returns a color value from red, green, blue values. Alpha will be set to 1.0f.

rgba :: CUChar -> CUChar -> CUChar -> CUChar -> Color

Returns a color value from red, green, blue and alpha values.

rgbaf :: CFloat -> CFloat -> CFloat -> CFloat -> Color

Returns a color value from red, green, blue and alpha values.

lerpRGBA :: Color -> Color -> CFloat -> Color

Linearly interpolates from color c0 to c1, and returns resulting color value.

transRGBA :: Color -> CUChar -> Color

Sets transparency of a color value.

transRGBAf :: Color -> CFloat -> Color

Sets transparency of a color value.

hsl :: CFloat -> CFloat -> CFloat -> Color

Returns color value specified by hue, saturation and lightness. HSL values are all in range [0..1], alpha will be set to 255.

hsla :: CFloat -> CFloat -> CFloat -> CUChar -> Color

Returns color value specified by hue, saturation and lightness and alpha. HSL values are all in range [0..1], alpha in range [0..255]

State handling

save :: Context -> IO ()

Pushes and saves the current render state into a state stack.

A matching restore must be used to restore the state.

restore :: Context -> IO ()

Pops and restores current render state.

reset :: Context -> IO ()

Resets current render state to default values. Does not affect the render state stack.

Render styles

strokeColor :: Context -> Color -> IO ()

Sets current stroke style to a solid color.

strokePaint :: Context -> Paint -> IO ()

Sets current stroke style to a paint, which can be a one of the gradients or a pattern.

fillColor :: Context -> Color -> IO ()

Sets current fill style to a solid color.

fillPaint :: Context -> Paint -> IO ()

Sets current fill style to a paint, which can be a one of the gradients or a pattern.

miterLimit :: Context -> CFloat -> IO ()

Sets the miter limit of the stroke style. Miter limit controls when a sharp corner is beveled.

strokeWidth :: Context -> CFloat -> IO ()

Sets the stroke width of the stroke style.

lineCap :: Context -> LineCap -> IO ()

Sets how the end of the line (cap) is drawn, Can be one of: Butt (default), Round, Square.

lineJoin :: Context -> LineCap -> IO ()

Sets how sharp path corners are drawn. Can be one of Miter (default), Round, 'Bevel.

globalAlpha :: Context -> CFloat -> IO ()

Sets the transparency applied to all rendered shapes. Already transparent paths will get proportionally more transparent as well.

Transforms

resetTransform :: Context -> IO ()

Resets current transform to a identity matrix.

transform :: Context -> CFloat -> CFloat -> CFloat -> CFloat -> CFloat -> CFloat -> IO ()

Premultiplies current coordinate system by specified matrix. The parameters are interpreted as matrix as follows:

[a c e]
[b d f]
[0 0 1]

translate :: Context -> CFloat -> CFloat -> IO ()

Translates current coordinate system.

rotate :: Context -> CFloat -> IO ()

Rotates current coordinate system. Angle is specified in radians.

skewX :: Context -> CFloat -> IO ()

Skews the current coordinate system along X axis. Angle is specified in radians.

skewY :: Context -> CFloat -> IO ()

Skews the current coordinate system along Y axis. Angle is specified in radians.

scale :: Context -> CFloat -> CFloat -> IO ()

Scales the current coordinate system.

currentTransform :: Context -> IO Transformation

Returns the current transformation matrix.

transformIdentity :: IO Transformation

Sets the transform to identity matrix.

transformTranslate :: CFloat -> CFloat -> IO Transformation

Sets the transform to translation matrix matrix.

transformScale :: CFloat -> CFloat -> IO Transformation

Sets the transform to scale matrix.

transformRotate :: CFloat -> IO Transformation

Sets the transform to rotate matrix. Angle is specified in radians.

transformSkewX :: CFloat -> IO Transformation

Sets the transform to skew-x matrix. Angle is specified in radians.

transformSkewY :: CFloat -> IO Transformation

Sets the transform to skew-y matrix. Angle is specified in radians.

transformMultiply :: Transformation -> Transformation -> IO Transformation

Sets the transform to the result of multiplication of two transforms, of A = A*B.

transformPremultiply :: Transformation -> Transformation -> IO Transformation

Sets the transform to the result of multiplication of two transforms, of A = B*A.

transformInverse :: Transformation -> IO Transformation

Sets the destination to inverse of specified transform. Returns 1 if the inverse could be calculated, else 0.

transformPoint :: Transformation -> CFloat -> CFloat -> (CFloat, CFloat)

Transform a point by given transform.

degToRad :: CFloat -> CFloat

Converts degrees to radians.

radToDeg :: CFloat -> CFloat

Converts radians to degrees.

Images

createImage :: Context -> FileName -> CInt -> IO (Maybe Image)

Creates image by loading it from the disk from specified file name.

createImageMem :: Context -> ImageFlags -> ByteString -> IO (Maybe Image)

Creates image by loading it from the specified chunk of memory.

createImageRGBA :: Context -> CInt -> CInt -> ImageFlags -> ByteString -> IO (Maybe Image)

Creates image from specified image data.

updateImage :: Context -> Image -> ByteString -> IO ()

Updates image data specified by image handle.

imageSize :: Context -> Image -> IO (CInt, CInt)

Returns the dimensions of a created image.

deleteImage :: Context -> Image -> IO ()

Deletes created image.

Paints

linearGradient :: Context -> CFloat -> CFloat -> CFloat -> CFloat -> Color -> Color -> IO Paint

Creates and returns a linear gradient. Parameters (sx,sy)-(ex,ey) specify the start and end coordinates of the linear gradient, icol specifies the start color and ocol the end color. The gradient is transformed by the current transform when it is passed to fillPaint or strokePaint.

boxGradient :: Context -> CFloat -> CFloat -> CFloat -> CFloat -> CFloat -> CFloat -> Color -> Color -> IO Paint

Creates and returns a box gradient. Box gradient is a feathered rounded rectangle, it is useful for rendering drop shadows or highlights for boxes. Parameters (x,y) define the top-left corner of the rectangle, (w,h) define the size of the rectangle, r defines the corner radius, and f feather. Feather defines how blurry the border of the rectangle is. Parameter icol specifies the inner color and ocol the outer color of the gradient. The gradient is transformed by the current transform when it is passed to fillPaint or strokePaint.

radialGradient :: Context -> CFloat -> CFloat -> CFloat -> CFloat -> Color -> Color -> IO Paint

Creates and returns a radial gradient. Parameters (cx,cy) specify the center, inr and outr specify the inner and outer radius of the gradient, icol specifies the start color and ocol the end color. The gradient is transformed by the current transform when it is passed to fillPaint or strokePaint.

imagePattern :: Context -> CFloat -> CFloat -> CFloat -> CFloat -> CFloat -> Image -> CFloat -> IO Paint

Creates and returns an image patter. Parameters (ox,oy) specify the left-top location of the image pattern, (ex,ey) the size of one image, angle rotation around the top-left corner, image is handle to the image to render. The gradient is transformed by the current transform when it is passed to fillPaint or strokePaint.

Scissoring

scissor :: Context -> CFloat -> CFloat -> CFloat -> CFloat -> IO ()

Sets the current scissor rectangle. The scissor rectangle is transformed by the current transform.

intersectScissor :: Context -> CFloat -> CFloat -> CFloat -> CFloat -> IO ()

Intersects current scissor rectangle with the specified rectangle. The scissor rectangle is transformed by the current transform. Note: in case the rotation of previous scissor rect differs from the current one, the intersection will be done between the specified rectangle and the previous scissor rectangle transformed in the current transform space. The resulting shape is always rectangle.

resetScissor :: Context -> IO ()

Reset and disables scissoring.

Paths

beginPath :: Context -> IO ()

Clears the current path and sub-paths.

moveTo :: Context -> CFloat -> CFloat -> IO ()

Starts new sub-path with specified point as first point.

lineTo :: Context -> CFloat -> CFloat -> IO ()

Adds line segment from the last point in the path to the specified point.

bezierTo :: Context -> CFloat -> CFloat -> CFloat -> CFloat -> CFloat -> CFloat -> IO ()

Adds cubic bezier segment from last point in the path via two control points to the specified point.

quadTo :: Context -> CFloat -> CFloat -> CFloat -> CFloat -> IO ()

Adds quadratic bezier segment from last point in the path via a control point to the specified point

arcTo :: Context -> CFloat -> CFloat -> CFloat -> CFloat -> CFloat -> IO ()

Adds an arc segment at the corner defined by the last path point, and two specified points.

closePath :: Context -> IO ()

Closes current sub-path with a line segment.

pathWinding :: Context -> CInt -> IO ()

Sets the current sub-path winding, see NVGwinding and NVGsolidity.

arc :: Context -> CFloat -> CFloat -> CFloat -> CFloat -> CFloat -> Winding -> IO ()

Creates new circle arc shaped sub-path. The arc center is at cx,cy, the arc radius is r, and the arc is drawn from angle a0 to a1, and swept in direction dir (NVG_CCW, or NVG_CW). Angles are specified in radians.

rect :: Context -> CFloat -> CFloat -> CFloat -> CFloat -> IO ()

Creates new rectangle shaped sub-path.

roundedRect :: Context -> CFloat -> CFloat -> CFloat -> CFloat -> CFloat -> IO ()

Creates new rounded rectangle shaped sub-path.

ellipse :: Context -> CFloat -> CFloat -> CFloat -> CFloat -> IO ()

Creates new ellipse shaped sub-path.

circle :: Context -> CFloat -> CFloat -> CFloat -> IO ()

Creates new circle shaped sub-path.

fill :: Context -> IO ()

Fills the current path with current fill style.

stroke :: Context -> IO ()

Fills the current path with current stroke style.