wxGraphicsContext

20202021 wxWidgets team. Licensed under the wxWindows Free Documentation Licence, Version 3 wxGraphicsContext

wxGraphicsContext Functions for wxGraphicsContext class

A wxGraphicsContext instance is the object that is drawn upon. It is created by a renderer using wxGraphicsRenderer:createContext/2. This can be 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.

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, 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.

See: wxGraphicsRenderer:createContext/2, wxGCDC, wxDC

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

wxWidgets docs: wxGraphicsContext

Creates a wxGraphicsContext from a wxWindow.

See: wxGraphicsRenderer:createContext/2

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

Creates a wxGraphicsContext from a wxWindowDC.

See: wxGraphicsRenderer:createContext/2

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.

Creates a native brush from a wxBrush.

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

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

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

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

See: createFont/3 Creates a native graphics font from a wxFont and a text 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.

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

See: createMatrix/2 Creates a native affine transformation matrix from the passed in values.

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

The default parameters result in an identity matrix.

Creates a native graphics path which is initially empty.

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:

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

Resets the clipping to original shape.

Draws the bitmap.

In case of a mono bitmap, this is treated as a mask and the current brushed is used for filling.

Draws an ellipse.

Draws the icon.

See: drawLines/3 Draws a polygon.

Draws a polygon.

See: drawPath/3 Draws the path by first filling and then stroking.

Draws the path by first filling and then stroking.

Draws a rectangle.

Draws a rounded rectangle.

Draws text at the defined position.

See: fillPath/3 Fills the path with the current brush.

Fills the path with the current brush.

Strokes along a path with the current pen.

Fills the widths array with the widths from the beginning of text to the corresponding character of text.

Gets the dimensions of the string using the currently selected font.

Rotates the current transformation matrix (in radians).

Scales the current transformation matrix.

Translates the current transformation matrix.

Gets the current transformation matrix of this context.

Sets the current transformation matrix of this context.

Concatenates the passed in transform with the current transform of this context.

Sets the brush for filling paths.

Sets the font for drawing text.

Remark: For Direct2D only TrueType fonts can be used.

Sets the pen used for stroking.

Strokes a single line.

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.