wxGraphicsContext(3erl)

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version 25.3.2.8 · 5 versions
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💅 wxGraphicsContext 💅

wxGraphicsContext(3erl) — Erlang module definition, bestie. This is the manual page for wxGraphicsContext, and it's coming at you in two parts. This is part 1, and we are not skipping a single flag, type, remark, or little weird detail. Periodt. 🫶

✨ NAME ✨

wxGraphicsContext - Functions for wxGraphicsContext class

🫶 DESCRIPTION 🫶

Okay so a wxGraphicsContext instance is literally the object that is drawn upon. It is created by a renderer using wxGraphicsRenderer:createContext/2. You can do that either directly using a renderer instance, or indirectly using the static convenience create/1 functions of wxGraphicsContext that always delegate the task to the default renderer. Slay.

Remark: For some renderers (like Direct2D or Cairo) processing of drawing operations may be deferred — Direct2D render target normally builds up a batch of rendering commands but defers processing of these commands, and Cairo operates on a separate surface. So to make drawing results visible you need to update the content of the context by calling wxGraphicsContext::Flush() (not implemented in wx) or by destroying the context. No cap, that's the whole vibe. 😭

See: wxGraphicsRenderer:createContext/2, wxGCDC, wxDC

This class is derived (and can use functions) from: wxGraphicsObject

wxWidgets docs: wxGraphicsContext

🧁 DATA TYPES 🧁

wxGraphicsContext() = wx:wx_object()

👑 EXPORTS 👑

Here's every export in this part. We're keeping the order, the signatures, the types, the little remarks — all of it. 💖

💖 destroy

destroy(This :: wxGraphicsContext()) -> ok

Creates a wxGraphicsContext from a wxWindow.

See: wxGraphicsRenderer:createContext/2

💖 create

create() -> wxGraphicsContext()
create(WindowDC) -> wxGraphicsContext()

Create a lightweight context that can be used only for measuring text. ✨

Types for create(WindowDC):

WindowDC =
    wxWindowDC:wxWindowDC() |
    wxWindow:wxWindow() |
    wxMemoryDC:wxMemoryDC() |
    wxImage:wxImage()

Creates a wxGraphicsContext from a wxWindowDC.

See: wxGraphicsRenderer:createContext/2

💖 createPen

createPen(This, Pen) -> wxGraphicsPen:wxGraphicsPen()

Types:

This = wxGraphicsContext()
Pen = wxPen:wxPen()

Creates a native pen from a wxPen.

Prefer to use the overload taking wxGraphicsPenInfo (not implemented in wx) unless you already have a wxPen as constructing one only to pass it to this method is wasteful. Ngl, the page is telling you to be efficient. 💅

💖 createBrush

createBrush(This, Brush) -> wxGraphicsBrush:wxGraphicsBrush()

Types:

This = wxGraphicsContext()
Brush = wxBrush:wxBrush()

Creates a native brush from a wxBrush.

💖 createRadialGradientBrush

createRadialGradientBrush(This, StartX, StartY, EndX, EndY, Radius, Stops) ->
                            wxGraphicsBrush:wxGraphicsBrush()
createRadialGradientBrush(This, StartX, StartY, EndX, EndY, Radius, OColor, CColor) ->
                            wxGraphicsBrush:wxGraphicsBrush()

Types for the Stops version:

This = wxGraphicsContext()
StartX = StartY = EndX = EndY = Radius = number()
Stops = wxGraphicsGradientStops:wxGraphicsGradientStops()

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Types for the OColor, CColor version:

This = wxGraphicsContext()
StartX = StartY = EndX = EndY = Radius = number()
OColor = CColor = wx:wx_colour()

Creates a native brush with a radial gradient. The brush originates at (@a startX, @a startY) and ends on a circle around (@a endX, @a endY) with the given @a radius. The gradient may be specified either by its start and end colours @a oColor and @a cColor or by a full set of gradient @a stops. The version taking wxGraphicsGradientStops is new in wxWidgets 2.9.1.

The ability to apply a transformation matrix to the gradient was added in 3.1.3

💖 createLinearGradientBrush

createLinearGradientBrush(This, X1, Y1, X2, Y2, Stops) ->
                            wxGraphicsBrush:wxGraphicsBrush()
createLinearGradientBrush(This, X1, Y1, X2, Y2, C1, C2) ->
                            wxGraphicsBrush:wxGraphicsBrush()

Types for the Stops version:

This = wxGraphicsContext()
X1 = Y1 = X2 = Y2 = number()
Stops = wxGraphicsGradientStops:wxGraphicsGradientStops()

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Types for the C1, C2 version:

This = wxGraphicsContext()
X1 = Y1 = X2 = Y2 = number()
C1 = C2 = wx:wx_colour()

Creates a native brush with a linear gradient. The brush starts at (@a x1, @a y1) and ends at (@a x2, @a y2). Either just the start and end gradient colours (@a c1 and @a c2) or full set of gradient @a stops can be specified. The version taking wxGraphicsGradientStops is new in wxWidgets 2.9.1.

The matrix parameter was added in wxWidgets 3.1.3

💖 createFont

First up:

createFont(This, Font) -> wxGraphicsFont:wxGraphicsFont()

Types:

This = wxGraphicsContext()
Font = wxFont:wxFont()

Then these two signatures:

createFont(This, SizeInPixels, Facename) -> wxGraphicsFont:wxGraphicsFont()
createFont(This, Font, Facename :: [Option]) -> wxGraphicsFont:wxGraphicsFont()

Types:

This = wxGraphicsContext()
Font = wxFont:wxFont()
Option = {col, wx:wx_colour()}

Creates a native graphics font from a wxFont and a text colour.

Remark: For Direct2D graphics fonts can be created from TrueType fonts only.

Then the one with Options:

createFont(This, SizeInPixels, Facename, Options :: [Option]) -> wxGraphicsFont:wxGraphicsFont()

Types:

This = wxGraphicsContext()
SizeInPixels = number()
Facename = unicode:chardata()
Option = {flags, integer()} | {col, wx:wx_colour()}

Creates a font object with the specified attributes.

The use of overload taking wxFont is preferred, see wxGraphicsRenderer:createFont/4 for more details.

Remark: For Direct2D graphics fonts can be created from TrueType fonts only.

Since: 2.9.3

💖 createMatrix

createMatrix(This) -> wxGraphicsMatrix:wxGraphicsMatrix()

Types:

This = wxGraphicsContext()
createMatrix(This, Options :: [Option]) -> wxGraphicsMatrix:wxGraphicsMatrix()

Types:

This = wxGraphicsContext()
Option =
    {a, number()} |
    {b, number()} |
    {c, number()} |
    {d, number()} |
    {tx, number()} |
    {ty, number()}

Creates a native affine transformation matrix from the passed in values.

The default parameters result in an identity matrix.

💖 createPath

createPath(This) -> wxGraphicsPath:wxGraphicsPath()

Types:

This = wxGraphicsContext()

Creates a native graphics path which is initially empty.

💖 clip

clip(This, Region) -> ok

Types:

This = wxGraphicsContext()
Region = wxRegion:wxRegion()

Sets the clipping region to the intersection of the given region and the previously set clipping region.

The clipping region is an area to which drawing is restricted.

Remark:

clip(This, X, Y, W, H) -> ok

Types:

This = wxGraphicsContext()
X = Y = W = H = number()

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

💖 resetClip

resetClip(This) -> ok

Types:

This = wxGraphicsContext()

Resets the clipping to original shape.

💖 drawBitmap

drawBitmap(This, Bmp, X, Y, W, H) -> ok

Types:

This = wxGraphicsContext()
Bmp = wxBitmap:wxBitmap()
X = Y = W = H = number()

Draws the bitmap.

In case of a mono bitmap, this is treated as a mask and the current brushed is used for filling. Yes, brushed — the page said it, I'm not arguing with the page. 😭

💖 drawEllipse

drawEllipse(This, X, Y, W, H) -> ok

Types:

This = wxGraphicsContext()
X = Y = W = H = number()

Draws an ellipse.

💖 drawIcon

drawIcon(This, Icon, X, Y, W, H) -> ok

Types:

This = wxGraphicsContext()
Icon = wxIcon:wxIcon()
X = Y = W = H = number()

Draws the icon.

💖 drawLines

drawLines(This, Points) -> ok

Types:

This = wxGraphicsContext()
Points = [{X :: float(), Y :: float()}]
drawLines(This, Points, Options :: [Option]) -> ok

Types:

This = wxGraphicsContext()
Points = [{X :: float(), Y :: float()}]
Option = {fillStyle, wx:wx_enum()}

Draws a polygon.

💖 drawPath

drawPath(This, Path) -> ok

Types:

This = wxGraphicsContext()
Path = wxGraphicsPath:wxGraphicsPath()
drawPath(This, Path, Options :: [Option]) -> ok

Types:

This = wxGraphicsContext()
Path = wxGraphicsPath:wxGraphicsPath()
Option = {fillStyle, wx:wx_enum()}

Draws the path by first filling and then stroking.

💖 drawRectangle

drawRectangle(This, X, Y, W, H) -> ok

Types:

This = wxGraphicsContext()
X = Y = W = H = number()

Draws a rectangle.

💖 drawRoundedRectangle

drawRoundedRectangle(This, X, Y, W, H, Radius) -> ok

Types:

This = wxGraphicsContext()
X = Y = W = H = Radius = number()

Draws a rounded rectangle.

💖 drawText

drawText(This, Str, X, Y) -> ok

Types:

This = wxGraphicsContext()
Str = unicode:chardata()
X = Y = number()

Draws text at the defined position.

drawText(This, Str, X, Y, Angle) -> ok
drawText(This, Str, X, Y, BackgroundBrush) -> ok

Types:

This = wxGraphicsContext()
Str = unicode:chardata()
X = Y = number()
BackgroundBrush = wxGraphicsBrush:wxGraphicsBrush()

Draws text at the defined position.

drawText(This, Str, X, Y, Angle, BackgroundBrush) -> ok

Types:

This = wxGraphicsContext()
Str = unicode:chardata()
X = Y = Angle = number()
BackgroundBrush = wxGraphicsBrush:wxGraphicsBrush()

Draws text at the defined position.

💖 fillPath

fillPath(This, Path) -> ok

Types:

This = wxGraphicsContext()
Path = wxGraphicsPath:wxGraphicsPath()
fillPath(This, Path, Options :: [Option]) -> ok

Types:

This = wxGraphicsContext()
Path = wxGraphicsPath:wxGraphicsPath()
Option = {fillStyle, wx:wx_enum()}

Fills the path with the current brush.

strokePath(This, Path) -> ok

Types:

  • This = wxGraphicsContext()
  • Path = wxGraphicsPath:wxGraphicsPath()

Strokes along a path using the current pen. That’s the whole vibe 💅

getPartialTextExtents(This, Text) -> [number()]

Types:

  • This = wxGraphicsContext()
  • Text = unicode:chardata()

Fills the widths array with the widths from the beginning of text to the corresponding character of text. Basically it gives you the width up to each character, bestie ✨

getTextExtent(This, Text) -> Result

Types:

  • Result = {Width :: number(), Height :: number(), Descent :: number(), ExternalLeading :: number()}
  • This = wxGraphicsContext()
  • Text = unicode:chardata()

Gets the dimensions of the string using the currently selected font. You get the whole little tuple package: width, height, descent, and external leading 🎀

rotate(This, Angle) -> ok

Types:

  • This = wxGraphicsContext()
  • Angle = number()

Rotates the current transformation matrix (in radians). Spin that matrix, icon behavior only 🌪️

scale(This, XScale, YScale) -> ok

Types:

  • This = wxGraphicsContext()
  • XScale = YScale = number()

Scales the current transformation matrix. Stretch it, shrink it, make it make sense 🦋

translate(This, Dx, Dy) -> ok

Types:

  • This = wxGraphicsContext()
  • Dx = Dy = number()

Translates the current transformation matrix. Move it along, no cap 📍

getTransform(This) -> wxGraphicsMatrix:wxGraphicsMatrix()

Types:

  • This = wxGraphicsContext()

Gets the current transformation matrix of this context. It hands you a wxGraphicsMatrix:wxGraphicsMatrix() and you’re like okay periodt 💜

setTransform(This, Matrix) -> ok

Types:

  • This = wxGraphicsContext()
  • Matrix = wxGraphicsMatrix:wxGraphicsMatrix()

Sets the current transformation matrix of this context. Swaps the whole transform vibe to the one you pass in 🔥

concatTransform(This, Matrix) -> ok

Types:

  • This = wxGraphicsContext()
  • Matrix = wxGraphicsMatrix:wxGraphicsMatrix()

Concatenates the passed-in transform with the current transform of this context. It’s giving “stack the matrices, bestie” 🫶

setBrush(This, Brush) -> ok

Types:

  • This = wxGraphicsContext()
  • Brush = wxGraphicsBrush:wxGraphicsBrush() | wxBrush:wxBrush()

Sets the brush for filling paths. Fill it up, make it cute 🌸

setFont(This, Font) -> ok

Types:

  • This = wxGraphicsContext()
  • Font = wxGraphicsFont:wxGraphicsFont()

Sets the font for drawing text. Font game: strong 💅

setFont(This, Font, Colour) -> ok

Types:

  • This = wxGraphicsContext()
  • Font = wxFont:wxFont()
  • Colour = wx:wx_colour()

Sets the font for drawing text, now with colour energy 🌈

Remark: For Direct2D only TrueType fonts can be used. 💀

setPen(This, Pen) -> ok

Types:

  • This = wxGraphicsContext()
  • Pen = wxPen:wxPen() | wxGraphicsPen:wxGraphicsPen()

Sets the pen used for stroking. Line work main character energy ✒️

strokeLine(This, X1, Y1, X2, Y2) -> ok

Types:

  • This = wxGraphicsContext()
  • X1 = Y1 = X2 = Y2 = number()

Strokes a single line. One little line, one big slay 📏

strokeLines(This, Points) -> ok

Types:

  • This = wxGraphicsContext()
  • Points = [{X :: float(), Y :: float()}]

Stroke lines connecting all the points. Unlike the other overload of this function, this method draws a single polyline and not a number of disconnected lines. So it’s one continuous path, not a bunch of separate little guys 💖

That’s the whole page, bestie 🎀. Footer shoutout: wxWidgets team, wx 2.2.2.1, page wxGraphicsContext(3erl) — bye! ✨

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