tcgfx::DeviceDrawableHelper Class Reference

#include <DeviceDrawableHelper.h>

Public Member Functions
	DeviceDrawableHelper (DeviceDrawable *root, color_t *palette, uint8_t paletteSize, const Coord &startPosition, const Coord &size)
	DeviceDrawableHelper (DeviceDrawable *root)
void	reConfigure (color_t *palette, uint8_t paletteSize, const Coord &startPosition, const Coord &size)
DeviceDrawable *	getDrawable ()
Coord	offsetLocation (const Coord &source) const
Coord	offsetLocation (const Coord &source, int xOffs, int yOffs) const
void	endDraw ()
void	setFont (const DeviceFontDrawingMode &font)
void	drawText (const Coord &where, color_t color, const char *text)
Coord	textExtents (const char *text, int *bl)
void	setFontFromParameters (const void *font, uint8_t mag)

Detailed Description

Wraps a drawable regardless of if we are on a sub device or root device, this class handles all the differences between the two with helper functions for dealing with palette colors and offset differences. It also has helpers that work out if TcUnicode(Adafruit or Unicode)/Native fonts are being used and calls the right drawing functions

Constructor & Destructor Documentation

DeviceDrawableHelper() [1/2]

DeviceDrawableHelper::DeviceDrawableHelper	(	DeviceDrawable *	root,
		color_t *	palette,
		uint8_t	paletteSize,
		const Coord &	startPosition,
		const Coord &	size
	)

Create a drawable helper given the drawable, palette, position and size, if it is possible, it will create a subdevice for drawing. When you call drawing functions that take a where coordinate, use the offsetLocation function that corrects for the sub drawable for you automatically.

Parameters

root	the root device drawable
palette	the palette of colors for the sub drawable
paletteSize	the size of the palette
startPosition	the starting position on the screen to draw at
size	how large the area is

DeviceDrawableHelper() [2/2]

DeviceDrawableHelper::DeviceDrawableHelper ( DeviceDrawable *  root )

explicit

For global constructions, we can also initially construct as root, and it will reconfigure later.

Parameters

root	the drawable that will act as root

Member Function Documentation

getDrawable()

DeviceDrawable* tcgfx::DeviceDrawableHelper::getDrawable ( )

inline

Get the drawable, not that this could be either the root device or a sub-device, always use offset location to ensure your where parameters are correctly positioned

Returns

the drawable

offsetLocation() [1/2]

Coord tcgfx::DeviceDrawableHelper::offsetLocation ( const Coord &  source ) const

inline

If on a sub-device, this call will correct the coordinate to match the area of the screen that the sub-device is drawing to.

Parameters

source

the source in screen coordinates

Returns

the coordinates correct for the current drawable

offsetLocation() [2/2]

Coord DeviceDrawableHelper::offsetLocation	(	const Coord &	source,
		int	xOffs,
		int	yOffs
	)		const

If on a sub-device, this call will correct the coordinate to match the area of the screen that the sub-device is drawing to.

Parameters

source	the source in screen coordinates
xOffs	an additional x offset to apply
yOffs	an additional y offset to apply

Returns

the coordinates correct for the current drawable

endDraw()

void tcgfx::DeviceDrawableHelper::endDraw ( )

inline

You must call this once drawing is concluded to ensure that the results are drawn, in the case of a sub-device this is critical.

setFont()

void tcgfx::DeviceDrawableHelper::setFont ( const DeviceFontDrawingMode &  font )

inline

Set the font drawing mode for the subsequent text operations

Parameters

font	the font drawing mode

drawText()

void DeviceDrawableHelper::drawText	(	const Coord &	where,
		color_t	color,
		const char *	text
	)

Draw text in the current font onto the display using the current drawable. Ensure you've called setFont before this with a suitable font.

Parameters

where	where to draw (will automatically apply offsetLocation)
color	the color to draw in (not the index)
text	the text to be presented

textExtents()

Coord DeviceDrawableHelper::textExtents	(	const char *	text,
		int *	bl
	)

Gets the size of the text for the current font as set by setFont. It's coordinates are returned, and the baseline is copied into the baseline parameter

Parameters

text	the text to measure
bl	the baseline pointer to fill in - int pointer

Returns

the size of the text.

setFontFromParameters()

void DeviceDrawableHelper::setFontFromParameters	(	const void *	font,
		uint8_t	mag
	)

Set the font from the theme font pointer and magnification values, by determining if tcUnicode is enabled and then choosing either native or TcUnicode based operation.

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

• src/graphics/DeviceDrawableHelper.h
• src/graphics/DeviceDrawableHelper.cpp