Collaboration diagram for Pebble::GContext:

Public Member Functions
	GContext (::GContext *ctx)
	Wraps an existing graphics context.

	operator::GContext * () const
	Instances of this class can be automatically converted to Pebble GContext pointer.

void	SetStrokeColor (GColor color) const

void	SetFillColor (GColor color) const

void	SetTextColor (GColor color) const

void	SetCompositingMode (GCompOp mode) const

void	SetAntialiased (bool enable) const

void	SetStrokeWidth (uint8_t stroke_width) const

void	DrawText (const char *text, GFont const font, const GRect box, const GTextOverflowMode overflow_mode=GTextOverflowModeWordWrap, const GTextAlignment alignment=GTextAlignmentLeft) const

void	DrawText (const char *text, GFont const font, const GRect box, const GTextOverflowMode overflow_mode, const GTextAlignment alignment, const GTextAttributes &text_attributes) const

void	DrawText (const std::string &text, GFont const font, const GRect box, const GTextOverflowMode overflow_mode=GTextOverflowModeWordWrap, const GTextAlignment alignment=GTextAlignmentLeft) const

void	DrawText (const std::string &text, GFont const font, const GRect box, const GTextOverflowMode overflow_mode, const GTextAlignment alignment, const GTextAttributes &text_attributes) const

void	DrawPixel (GPoint point) const

void	DrawLine (GPoint p0, GPoint p1) const

void	DrawRect (GRect rect) const

void	FillRect (GRect rect, uint16_t corner_radius, GCornerMask corner_mask) const

void	DrawCircle (GPoint p, uint16_t radius) const

void	FillCircle (GPoint p, uint16_t radius) const

void	DrawRoundRect (GRect rect, uint16_t radius) const

void	DrawBitmapInRect (const GBitmap &bitmap, GRect rect) const

GBitmap	CaptureFrameBuffer ()
	A shortcut to capture the framebuffer in the native format of the watch.

GBitmap	CaptureFrameBuffer (GBitmapFormat format)

bool	ReleaseFrameBuffer (const GBitmap &buffer)

bool	FrameBufferIsCaptured ()

void	DrawRotatedBitmap (const GBitmap &src, GPoint src_ic, int rotation, GPoint dest_ic) const

void	DrawArc (GRect rect, GOvalScaleMode scale_mode, int32_t angle_start, int32_t angle_end) const

void	FillRadial (GRect rect, GOvalScaleMode scale_mode, uint16_t inset_thickness, int32_t angle_start, int32_t angle_end) const

Static Public Member Functions
static GSize	GetContentSize (const char *text, GFont const font, const GRect box, const GTextOverflowMode overflow_mode=GTextOverflowModeWordWrap, const GTextAlignment alignment=GTextAlignmentLeft)

static GSize	GetContentSize (const char *text, GFont const font, const GRect box, const GTextOverflowMode overflow_mode, const GTextAlignment alignment, const GTextAttributes &text_attributes)

static GSize	GetContentSize (const std::string &text, GFont const font, const GRect box, const GTextOverflowMode overflow_mode=GTextOverflowModeWordWrap, const GTextAlignment alignment=GTextAlignmentLeft)

static GSize	GetContentSize (const std::string &text, GFont const font, const GRect box, const GTextOverflowMode overflow_mode, const GTextAlignment alignment, const GTextAttributes &text_attributes)

Protected Attributes
::GContext *	gcontext_

Member Function Documentation

◆ CaptureFrameBuffer()

GBitmap Pebble::GContext::CaptureFrameBuffer ( GBitmapFormat format )

inline

Captures the frame buffer for direct access, using the given format. Graphics functions will not affect the frame buffer while it is captured. The frame buffer is released when ReleaseFrameBuffer is called. The frame buffer must be released before the end of a layer's .update_proc for the layer to be drawn properly.

While the frame buffer is captured calling CaptureFrameBuffer will fail and return and invalid GBitmap

Note: When writing to the frame buffer, you should respect the visible boundaries of a window on the screen. Use layer_get_frame(window_get_root_layer(window)).origin to obtain its position relative to the frame buffer. For example, drawing to (5, 5) in the frame buffer while the window is transitioning to the left with its origin at (-20, 0) would effectively draw that point at (25, 5) relative to the window. For this reason you should consider the window's root layer frame when calculating drawing coordinates.

See also: GBitmap; GBitmapFormat; layer_get_frame; window_get_root_layer

Parameters

ctx	The graphics context providing the frame buffer
format	The format in which the framebuffer should be captured. Supported formats are GBitmapFormat1Bit and GBitmapFormat8Bit.

Returns: A pointer to the frame buffer. Invalid if failed.

◆ DrawArc()

void Pebble::GContext::DrawArc	(	GRect	rect,
		GOvalScaleMode	scale_mode,
		int32_t	angle_start,
		int32_t	angle_end
	)		const

inline

Draws a line arc clockwise between angle_start and angle_end, where 0° is the top of the circle. If the difference between angle_start and angle_end is greater than 360°, a full circle will be drawn.

Parameters

rect	The reference rectangle to derive the center point and radius (see scale_mode).
scale_mode	Determines how rect will be used to derive the center point and radius.
angle_start	Radial starting angle. Use DEG_TO_TRIGANGLE to easily convert degrees to the appropriate value.
angle_end	Radial finishing angle. If smaller than `angle_start`, nothing will be drawn.

◆ DrawBitmapInRect()

void Pebble::GContext::DrawBitmapInRect	(	const GBitmap &	bitmap,
		GRect	rect
	)		const

inline

Draws a bitmap into the graphics context, inside the specified rectangle

Parameters

bitmap	The bitmap to draw
rect	The rectangle in which to draw the bitmap

Note: If the size of rect is smaller than the size of the bitmap, the bitmap will be clipped on right and bottom edges. If the size of rect is larger than the size of the bitmap, the bitmap will be tiled automatically in both horizontal and vertical directions, effectively drawing a repeating pattern.

See also: GBitmap; GContext

◆ DrawCircle()

void Pebble::GContext::DrawCircle	(	GPoint	p,
		uint16_t	radius
	)		const

inline

Draws the outline of a circle in the current stroke color

Parameters

p	The center point of the circle
radius	The radius in pixels

◆ DrawLine()

void Pebble::GContext::DrawLine	(	GPoint	p0,
		GPoint	p1
	)		const

inline

Draws line in the current stroke color, current stroke width and AA flag

Parameters

p0	The starting point of the line
p1	The ending point of the line

◆ DrawPixel()

void Pebble::GContext::DrawPixel ( GPoint point ) const

inline

Draws a pixel at given point in the current stroke color

Parameters

point The point at which to draw the pixel

◆ DrawRect()

void Pebble::GContext::DrawRect ( GRect rect ) const

inline

Draws a 1-pixel wide rectangle outline in the current stroke color

Parameters

rect	The rectangle for which to draw the outline

◆ DrawRotatedBitmap()

void Pebble::GContext::DrawRotatedBitmap	(	const GBitmap &	src,
		GPoint	src_ic,
		int	rotation,
		GPoint	dest_ic
	)		const

inline

Draws a rotated bitmap with a memory-sensitive 2x anti-aliasing technique (using ray-finding instead of super-sampling), which is thresholded into a b/w bitmap for 1-bit and color blended for 8-bit.

Note: This API has performance limitations that can degrade user experience. Use sparingly.

Parameters

src	The source bitmap to draw
src_ic	Instance center (single point unaffected by rotation) relative to source bitmap
rotation	Angle of rotation. Rotation is an integer between 0 (no rotation) and TRIG_MAX_ANGLE (360 degree rotation). Use DEG_TO_TRIGANGLE to easily convert degrees to the appropriate value.
dest_ic	Where to draw the instance center of the rotated bitmap in the context.

◆ DrawRoundRect()

void Pebble::GContext::DrawRoundRect	(	GRect	rect,
		uint16_t	radius
	)		const

inline

Draws the outline of a rounded rectangle in the current stroke color

Parameters

rect	The rectangle defining the dimensions of the rounded rectangle to draw
radius	The corner radius in pixels

◆ DrawText() [1/4]

void Pebble::GContext::DrawText	(	const char *	text,
		GFont const	font,
		const GRect	box,
		const GTextOverflowMode	overflow_mode,
		const GTextAlignment	alignment,
		const GTextAttributes &	text_attributes
	)		const

inline

Draw text into the current graphics context, using the context's current text color. The text will be drawn inside a box with the specified dimensions and configuration, with clipping occuring automatically.

Parameters

text	The zero terminated UTF-8 string to draw
font	The font in which the text should be set
box	The bounding box in which to draw the text. The first line of text will be drawn against the top of the box.
overflow_mode	The overflow behavior, in case the text is larger than what fits inside the box.
alignment	The horizontal alignment of the text
text_attributes	Optional text attributes to describe the characteristics of the text

◆ DrawText() [2/4]

void Pebble::GContext::DrawText	(	const char *	text,
		GFont const	font,
		const GRect	box,
		const GTextOverflowMode	overflow_mode = `GTextOverflowModeWordWrap`,
		const GTextAlignment	alignment = `GTextAlignmentLeft`
	)		const

inline

Draw text into the current graphics context, using the context's current text color. The text will be drawn inside a box with the specified dimensions and configuration, with clipping occuring automatically.

Parameters

text	The zero terminated UTF-8 string to draw
font	The font in which the text should be set
box	The bounding box in which to draw the text. The first line of text will be drawn against the top of the box.
overflow_mode	The overflow behavior, in case the text is larger than what fits inside the box.
alignment	The horizontal alignment of the text

◆ DrawText() [3/4]

void Pebble::GContext::DrawText	(	const std::string &	text,
		GFont const	font,
		const GRect	box,
		const GTextOverflowMode	overflow_mode,
		const GTextAlignment	alignment,
		const GTextAttributes &	text_attributes
	)		const

inline

Draw text into the current graphics context, using the context's current text color. The text will be drawn inside a box with the specified dimensions and configuration, with clipping occuring automatically.

Parameters

text	The zero terminated UTF-8 string to draw
font	The font in which the text should be set
box	The bounding box in which to draw the text. The first line of text will be drawn against the top of the box.
overflow_mode	The overflow behavior, in case the text is larger than what fits inside the box.
alignment	The horizontal alignment of the text
text_attributes	Optional text attributes to describe the characteristics of the text

◆ DrawText() [4/4]

void Pebble::GContext::DrawText	(	const std::string &	text,
		GFont const	font,
		const GRect	box,
		const GTextOverflowMode	overflow_mode = `GTextOverflowModeWordWrap`,
		const GTextAlignment	alignment = `GTextAlignmentLeft`
	)		const

inline

Draw text into the current graphics context, using the context's current text color. The text will be drawn inside a box with the specified dimensions and configuration, with clipping occuring automatically.

Parameters

text	The zero terminated UTF-8 string to draw
font	The font in which the text should be set
box	The bounding box in which to draw the text. The first line of text will be drawn against the top of the box.
overflow_mode	The overflow behavior, in case the text is larger than what fits inside the box.
alignment	The horizontal alignment of the text

◆ FillCircle()

void Pebble::GContext::FillCircle	(	GPoint	p,
		uint16_t	radius
	)		const

inline

Fills a circle in the current fill color

Parameters

p	The center point of the circle
radius	The radius in pixels

◆ FillRadial()

void Pebble::GContext::FillRadial	(	GRect	rect,
		GOvalScaleMode	scale_mode,
		uint16_t	inset_thickness,
		int32_t	angle_start,
		int32_t	angle_end
	)		const

inline

Fills a circle clockwise between angle_start and angle_end, where 0° is the top of the circle. If the difference between angle_start and angle_end is greater than 360°, a full circle will be drawn and filled. If angle_start is greater than angle_end nothing will be drawn.

Note: A simple example is drawing a 'Pacman' shape, with a starting angle of -225°, and ending angle of 45°. By setting inset_thickness to a non-zero value (such as 30) this example will produce the letter C.

Parameters

rect	The reference rectangle to derive the center point and radius (see scale).
scale_mode	Determines how rect will be used to derive the center point and radius.
inset_thickness	Describes how thick in pixels the radial will be drawn towards its center measured from the outside.
angle_start	Radial starting angle. Use DEG_TO_TRIGANGLE to easily convert degrees to the appropriate value.
angle_end	Radial finishing angle. If smaller than `angle_start`, nothing will be drawn.

◆ FillRect()

void Pebble::GContext::FillRect	(	GRect	rect,
		uint16_t	corner_radius,
		GCornerMask	corner_mask
	)		const

inline

Fills a rectangle with the current fill color, optionally rounding all or a selection of its corners.

Parameters

ctx	The destination graphics context in which to draw
rect	The rectangle to fill
corner_radius	The rounding radius of the corners in pixels (maximum is 8 pixels)
corner_mask	Bitmask of the corners that need to be rounded.

See also: GCornerMask

◆ FrameBufferIsCaptured()

bool Pebble::GContext::FrameBufferIsCaptured ( )

inline

Whether or not the frame buffer has been captured by graphics_capture_frame_buffer. Graphics functions will not affect the frame buffer until it has been released by graphics_release_frame_buffer.

Returns: True if the frame buffer has been captured

◆ GetContentSize() [1/4]

static GSize Pebble::GContext::GetContentSize	(	const char *	text,
		GFont const	font,
		const GRect	box,
		const GTextOverflowMode	overflow_mode,
		const GTextAlignment	alignment,
		const GTextAttributes &	text_attributes
	)

inlinestatic

Obtain the maximum size that a text with given font, overflow mode and alignment occupies within a given rectangular constraint.

Parameters

text	The zero terminated UTF-8 string for which to calculate the size
font	The font in which the text should be set while calculating the size
box	The bounding box in which the text should be constrained
overflow_mode	The overflow behavior, in case the text is larger than what fits inside the box.
alignment	The horizontal alignment of the text
text_attributes	Optional text attributes to describe the characteristics of the text

Returns: The maximum size occupied by the text

See also: app_graphics_text_layout_get_content_size

◆ GetContentSize() [2/4]

static GSize Pebble::GContext::GetContentSize	(	const char *	text,
		GFont const	font,
		const GRect	box,
		const GTextOverflowMode	overflow_mode = `GTextOverflowModeWordWrap`,
		const GTextAlignment	alignment = `GTextAlignmentLeft`
	)

inlinestatic

Obtain the maximum size that a text with given font, overflow mode and alignment occupies within a given rectangular constraint.

Parameters

text	The zero terminated UTF-8 string for which to calculate the size
font	The font in which the text should be set while calculating the size
box	The bounding box in which the text should be constrained
overflow_mode	The overflow behavior, in case the text is larger than what fits inside the box.
alignment	The horizontal alignment of the text

Returns: The maximum size occupied by the text

See also: app_graphics_text_layout_get_content_size_with_attributes

◆ GetContentSize() [3/4]

static GSize Pebble::GContext::GetContentSize	(	const std::string &	text,
		GFont const	font,
		const GRect	box,
		const GTextOverflowMode	overflow_mode,
		const GTextAlignment	alignment,
		const GTextAttributes &	text_attributes
	)

inlinestatic

Obtain the maximum size that a text with given font, overflow mode and alignment occupies within a given rectangular constraint.

Parameters

text	The zero terminated UTF-8 string for which to calculate the size
font	The font in which the text should be set while calculating the size
box	The bounding box in which the text should be constrained
overflow_mode	The overflow behavior, in case the text is larger than what fits inside the box.
alignment	The horizontal alignment of the text
text_attributes	Optional text attributes to describe the characteristics of the text

Returns: The maximum size occupied by the text

See also: app_graphics_text_layout_get_content_size

◆ GetContentSize() [4/4]

static GSize Pebble::GContext::GetContentSize	(	const std::string &	text,
		GFont const	font,
		const GRect	box,
		const GTextOverflowMode	overflow_mode = `GTextOverflowModeWordWrap`,
		const GTextAlignment	alignment = `GTextAlignmentLeft`
	)

inlinestatic

Obtain the maximum size that a text with given font, overflow mode and alignment occupies within a given rectangular constraint.

Parameters

text	The zero terminated UTF-8 string for which to calculate the size
font	The font in which the text should be set while calculating the size
box	The bounding box in which the text should be constrained
overflow_mode	The overflow behavior, in case the text is larger than what fits inside the box.
alignment	The horizontal alignment of the text

Returns: The maximum size occupied by the text

See also: app_graphics_text_layout_get_content_size_with_attributes

◆ ReleaseFrameBuffer()

bool Pebble::GContext::ReleaseFrameBuffer ( const GBitmap & buffer )

inline

Releases the frame buffer. Must be called before the end of a layer's .update_proc for the layer to be drawn properly.

If buffer does not point to the address previously returned by graphics_capture_frame_buffer the frame buffer will not be released.

Parameters

buffer The frame buffer bitmap

Returns: True if the frame buffer was released successfully

◆ SetAntialiased()

void Pebble::GContext::SetAntialiased ( bool enable ) const

inline

Sets whether antialiasing is applied to stroke drawing

Parameters

enable True = antialiasing enabled, False = antialiasing disabled

Note: Default value is true.

◆ SetCompositingMode()

void Pebble::GContext::SetCompositingMode ( GCompOp mode ) const

inline

Sets the current bitmap compositing mode of the graphics context.

Parameters

mode	The new compositing mode

See also: GCompOp; bitmap_layer_set_compositing_mode()

Note: At the moment, this only affects the bitmaps drawing operations – graphics_draw_bitmap_in_rect(), graphics_draw_rotated_bitmap, and anything that uses those APIs –, but it currently does not affect the filling or stroking operations.

◆ SetFillColor()

void Pebble::GContext::SetFillColor ( GColor color ) const

inline

Sets the current fill color of the graphics context.

Parameters

color The new fill color

◆ SetStrokeColor()

void Pebble::GContext::SetStrokeColor ( GColor color ) const

inline

Sets the current stroke color of the graphics context.

Parameters

color The new stroke color

◆ SetStrokeWidth()

void Pebble::GContext::SetStrokeWidth ( uint8_t stroke_width ) const

inline

Sets the width of the stroke for drawing routines

Parameters

stroke_width Width in pixels of the stroke.

Note: If stroke width of zero is passed, it will be ignored and will not change the value stored in GContext. Currently, only odd stroke_width values are supported. If an even value is passed in, the value will be stored as is, but the drawing routines will round down to the previous integral value when drawing. Default value is 1.

◆ SetTextColor()

void Pebble::GContext::SetTextColor ( GColor color ) const

inline

Sets the current text color of the graphics context.

Parameters

color The new text color

The documentation for this class was generated from the following file:

include/pebble_graphics_context.hpp

Public Member Functions

Static Public Member Functions

Protected Attributes

Member Function Documentation

◆ CaptureFrameBuffer()

◆ DrawArc()

◆ DrawBitmapInRect()

◆ DrawCircle()

◆ DrawLine()

◆ DrawPixel()

◆ DrawRect()

◆ DrawRotatedBitmap()

◆ DrawRoundRect()

◆ DrawText() [1/4]

◆ DrawText() [2/4]

◆ DrawText() [3/4]

◆ DrawText() [4/4]

◆ FillCircle()

◆ FillRadial()

◆ FillRect()

◆ FrameBufferIsCaptured()

◆ GetContentSize() [1/4]

◆ GetContentSize() [2/4]

◆ GetContentSize() [3/4]

◆ GetContentSize() [4/4]

◆ ReleaseFrameBuffer()

◆ SetAntialiased()

◆ SetCompositingMode()

◆ SetFillColor()

◆ SetStrokeColor()

◆ SetStrokeWidth()

◆ SetTextColor()