MicroEJ MicroVG library low level API: helper to implement library natives methods. More...

#include <sni.h>
#include "vg_configuration.h"

Macros
#define	VG_LOG_ERROR(fmt, ...) VG_LOG_ERROR_PRINT(fmt, ## __VA_ARGS__)
	Logs an error. The format has no trailing line return. More...

#define	VG_LOG_INFO(fmt, ...)
	Logs an informative message. The format has no trailing line return. More...

#define	MEJ_LOG_ERROR_MICROVG(fmt, ...) VG_LOG_ERROR(fmt, ## __VA_ARGS__)
	Deprecated, use VG_LOG_ERROR(). Kept for the Abstraction Layers that build on this one.

#define	MEJ_LOG_INFO_MICROVG(fmt, ...) VG_LOG_INFO(fmt, ## __VA_ARGS__)
	Deprecated, use VG_LOG_INFO(). Kept for the Abstraction Layers that build on this one.

#define	VG_HELPER_NULL_GRADIENT 0
	Set this define to monitor freetype heap evolution. It needs VG_LOG_INFO_ENABLED to print the heap logs. More...

#define	FT_FACE_FLAG_COMPLEX_LAYOUT (((uint32_t)1) << 31)
	Freetype supplementary flag for complex layout Uses a free bit in freetype face flags to convey the complex layout mode information with the freetype face. freetype.h must be checked on freetype update to ensure that this bit is still free.

#define	M_PI 3.1415926535

#define	RAD_TO_DEG(r) ((r) * (180.0f / M_PI))

#define	DEG_TO_RAD(d) (((d) * M_PI) / 180.0f)

#define	JFLOAT_TO_UINT32_t(f) ((uint32_t )&(f))

#define	UINT32_t_TO_JFLOAT(i) ((float )&(i))

#define	REGISTERDESC(desc, buf, buf_len) if ((buf_len) >= sizeof(desc)) { (void)memcpy((buf), (desc), sizeof(desc)); }
	Registers the description of a SNI close function.

Functions
void	LLUI_DISPLAY_waitAsynchronousDrawingEnd (void)
	Waits until the end of current asynchronous drawing. More...

int	VG_HELPER_get_utf (const unsigned short text, int length, int offset)
	Gets the UTF character from a text buffer at the given offset and updates the offset to point to the next character. More...

void	VG_HELPER_layout_configure (int faceHandle, const unsigned short *text, int length)
	Configures the font layouter with a font and a text. More...

void	VG_HELPER_layout_dispose (int faceHandle)
	Releases the font layouter's state built from a font face, when that face is about to be freed. Does nothing when the layouter holds no state for this face. More...

bool	VG_HELPER_layout_load_glyph (uint32_t glyph_idx, int x_advance, int y_advance, int x_offset, int *y_offset)
	Loads the next layouted glyph and gets index and positions. More...

void	VG_HELPER_layout_stop (void)
	Releases what the layouter still holds for the current iteration. Does nothing when there is nothing to release, so a caller that may or may not have stopped early calls it either way, and calling it twice is safe. More...

const jfloat *	VG_HELPER_check_matrix (const jfloat *matrix)
	Checks if the matrix is null. In that case, returns an identity matrix. This allows to prevent to make some checks on the matrix in the algorithms. More...

uint32_t	VG_HELPER_apply_alpha (uint32_t color, uint32_t alpha)
	Applies the global opacity on given color. More...

void	VG_HELPER_prepare_matrix (jfloat dest, jfloat x, jfloat y, const jfloat matrix)
	Converts a MicroVG matrix in another MicroVG matrix applying a translation. More...

Detailed Description

MicroEJ MicroVG library low level API: helper to implement library natives methods.

Author: MicroEJ Developer Team

Version: 8.0.3

Definition in file vg_helper.h.

Macro Definition Documentation

◆ VG_HELPER_NULL_GRADIENT

#define VG_HELPER_NULL_GRADIENT 0

Set this define to monitor freetype heap evolution. It needs VG_LOG_INFO_ENABLED to print the heap logs.

NULL Gradient value

Definition at line 75 of file vg_helper.h.

◆ VG_LOG_ERROR

#define VG_LOG_ERROR	(	fmt,
		...
	)	VG_LOG_ERROR_PRINT(fmt, ## __VA_ARGS__)

Logs an error. The format has no trailing line return.

The errors are always compiled. The printer is VG_LOG_ERROR_PRINT() (see vg_configuration.h).

Definition at line 42 of file vg_helper.h.

◆ VG_LOG_INFO

#define VG_LOG_INFO	(	fmt,
		...
	)

Logs an informative message. The format has no trailing line return.

Compiled only when VG_LOG_INFO_ENABLED is 1. The printer is VG_LOG_INFO_PRINT() (see vg_configuration.h).

Definition at line 53 of file vg_helper.h.

Function Documentation

◆ LLUI_DISPLAY_waitAsynchronousDrawingEnd()

void LLUI_DISPLAY_waitAsynchronousDrawingEnd ( void )

Waits until the end of current asynchronous drawing.

To avoid potential side effects from the release of objects (images, fonts) retained by a feature during the killing of that feature, ensure that no third-party components (e.g., GPU) are using these objects at the time of the kill.

UI packs with versions higher than 14.5.1 provide the blocking API LLUI_DISPLAY_waitAsynchronousDrawingEnd(). This API is stubbed on the VG Pack for backward compatibility issues between VG Pack 1.8.0 and UI Packs [14.4.0, 14.5.1]. However, it is highly recommended to use a UI Pack version greater than 14.5.1.

Definition at line 157 of file vg_helper.c.

                                                                          {
     // cannot wait the end of drawing with UI packs [14.4.0-14.5.1]
 }

◆ VG_HELPER_apply_alpha()

uint32_t VG_HELPER_apply_alpha	(	uint32_t	color,
		uint32_t	alpha
	)

Applies the global opacity on given color.

Parameters

[in]	color	the 32-bit color.
[in]	alpha	the opacity.

Returns: the new color.

Definition at line 352 of file vg_helper.c.

                                                                {
     uint32_t color_alpha = (((color >> 24) & (uint32_t)0xff) * alpha) / (uint32_t)255;
     return (color & (uint32_t)0xffffff) | (color_alpha << 24);
 }

◆ VG_HELPER_check_matrix()

const jfloat* VG_HELPER_check_matrix ( const jfloat * matrix )

Checks if the matrix is null. In that case, returns an identity matrix. This allows to prevent to make some checks on the matrix in the algorithms.

The identity matrix can be used several times by the same algorithm. The caller must not modify it (read-only matrix).

Parameters

[in] matrix the matrix to check

Returns: the matrix or an identity matrix

Definition at line 347 of file vg_helper.c.

                                                             {
     return (NULL == matrix) ? g_identity_matrix : matrix;
 }

◆ VG_HELPER_get_utf()

int VG_HELPER_get_utf	(	const unsigned short *	text,
		int	length,
		int *	offset
	)

Gets the UTF character from a text buffer at the given offset and updates the offset to point to the next character.

Some characters have some special values; they are made up of two Unicode characters in two specific ranges such that the first Unicode character is in one range (for example 0xD800-0xD8FF) and the second Unicode character is in the second range (for example 0xDC00-0xDCFF). This is called a surrogate pair.

If a surrogate pair is incomplete (missing second character), this function returns "0" (error) and does not update the offset.

Parameters

[in]	text	text buffer encoded in UTF16 where to read UTF character.
[in]	length	lenght of the text buffer.
[in,out]	offset	offset in the text buffer where to read UTF character. Updated to the next character position.

Returns: The decoded UTF character.

Definition at line 166 of file vg_helper.c.

                                                                                   {
     unsigned short highPart = GET_NEXT_CHARACTER(textCharRam, length, *offset);
     int ret = 0; // means "error" (see doc)
  
     if ((highPart >= MIN_HIGH_SURROGATE) && (highPart <= MAX_HIGH_SURROGATE)) {
         if (*offset < (length - 1)) {
             unsigned short lowPart = GET_NEXT_CHARACTER(textCharRam, length, *(offset) + 1);
  
             if ((lowPart >= MIN_LOW_SURROGATE) && (lowPart <= MAX_LOW_SURROGATE)) {
                 *offset += 2;
  
                 ret = 0;
                 ret += ((int)highPart - (int)MIN_HIGH_SURROGATE);
                 ret <<= (int)10;
                 ret += ((int)lowPart - (int)MIN_LOW_SURROGATE);
                 ret += (int)MIN_SUPPLEMENTARY_CODE_POINT;
             }
             // else: invalid surrogate pair
         }
         // else: missing second part of surrogate pair
     } else {
         *offset += 1;
  
         // standard character
         ret = 0x0000FFFF & (int)highPart;
     }
  
     return ret;
 }

◆ VG_HELPER_layout_configure()

void VG_HELPER_layout_configure	(	int	faceHandle,
		const unsigned short *	text,
		int	length
	)

Configures the font layouter with a font and a text.

Releases what an iteration left open, as VG_HELPER_layout_stop() does, so a caller that stops before the end of its own iteration costs the next caller nothing.

Parameters

[in]	faceHandle	handle on font face.
[in]	text	text buffer encoded in UTF16 where to read UTF character.
[in]	length	text buffer length.

◆ VG_HELPER_layout_dispose()

void VG_HELPER_layout_dispose ( int faceHandle )

Releases the font layouter's state built from a font face, when that face is about to be freed. Does nothing when the layouter holds no state for this face.

Must be called before the face itself is freed: the state holds the face and reads through it for its whole life.

Parameters

[in] faceHandle handle on the font face being freed.

◆ VG_HELPER_layout_load_glyph()

bool VG_HELPER_layout_load_glyph	(	uint32_t *	glyph_idx,
		int *	x_advance,
		int *	y_advance,
		int *	x_offset,
		int *	y_offset
	)

Loads the next layouted glyph and gets index and positions.

Parameters

[out]	glyph_idx	next glyph index.
[out]	x_advance	the horizontal advance to add to the cursor position after drawing the glyph.
[out]	y_advance	the vertical advance to add to thecursor after drawing the glyph.
[out]	x_offset	the hozizontal offset of the glyph, does not affect the cursor position.
[out]	y_offset	the vertical offset of the glyph, does not affect the cursor position.

Returns: true if a glyph is available otherwise false.

◆ VG_HELPER_layout_stop()

void VG_HELPER_layout_stop ( void )

Releases what the layouter still holds for the current iteration. Does nothing when there is nothing to release, so a caller that may or may not have stopped early calls it either way, and calling it twice is safe.

It does not reset the reading position, so the next iteration starts with VG_HELPER_layout_configure() as it always did.

◆ VG_HELPER_prepare_matrix()

void VG_HELPER_prepare_matrix	(	jfloat *	dest,
		jfloat	x,
		jfloat	y,
		const jfloat *	matrix
	)

Converts a MicroVG matrix in another MicroVG matrix applying a translation.

Parameters

[out]	dest	the MicroVG matrix to set
[in]	x	the X translation to apply
[in]	y	the Y translation to apply
[in]	matrix	the MicroVG transformation to apply (can be null)

Definition at line 358 of file vg_helper.c.

                                                                                       {
     const jfloat *local_matrix = VG_HELPER_check_matrix(matrix);
  
     if ((0 != x) || (0 != y)) {
         // Create translate matrix for initial x,y translation from graphicscontext.
         LLVG_MATRIX_IMPL_setTranslate(dest, x, y);
         LLVG_MATRIX_IMPL_concatenate(dest, local_matrix);
     } else {
         // use original matrix
         LLVG_MATRIX_IMPL_copy(dest, local_matrix);
     }
 }

Macros

Functions

Detailed Description

Macro Definition Documentation

◆ VG_HELPER_NULL_GRADIENT

◆ VG_LOG_ERROR

◆ VG_LOG_INFO

Function Documentation

◆ LLUI_DISPLAY_waitAsynchronousDrawingEnd()

◆ VG_HELPER_apply_alpha()

◆ VG_HELPER_check_matrix()

◆ VG_HELPER_get_utf()

◆ VG_HELPER_layout_configure()

◆ VG_HELPER_layout_dispose()

◆ VG_HELPER_layout_load_glyph()

◆ VG_HELPER_layout_stop()

◆ VG_HELPER_prepare_matrix()