General Utilities

Some functions that are handy but are not specific of canvas or objects. More...

Functions
EVAS_API const char *	evas_load_error_str (Evas_Load_Error error)
	Converts the given Evas image load error code into a string describing it in human-readable text. More...
EVAS_API void	evas_color_hsv_to_rgb (float h, float s, float v, int *r, int *g, int *b)
	Convert a given color from HSV to RGB format. More...
EVAS_API void	evas_color_rgb_to_hsv (int r, int g, int b, float *h, float *s, float *v)
	Convert a given color from RGB to HSV format. More...
EVAS_API void	evas_color_argb_premul (int a, int *r, int *g, int *b)
	Pre-multiplies a rgb triplet by an alpha factor. More...
EVAS_API void	evas_color_argb_unpremul (int a, int *r, int *g, int *b)
	Undo pre-multiplication of a rgb triplet by an alpha factor. More...
EVAS_API void	evas_data_argb_premul (unsigned int *data, unsigned int len)
	Pre-multiplies data by an alpha factor. More...
EVAS_API void	evas_data_argb_unpremul (unsigned int *data, unsigned int len)
	Undo pre-multiplication data by an alpha factor. More...
EVAS_API int	evas_string_char_next_get (const char *str, int pos, int *decoded)
	Gets the next character in the string. More...
EVAS_API int	evas_string_char_prev_get (const char *str, int pos, int *decoded)
	Gets the previous character in the string. More...
EVAS_API int	evas_string_char_len_get (const char *str)
	Get the length in characters of the string. More...
EVAS_API Evas_BiDi_Direction	evas_language_direction_get (void)
	Get language direction. More...
EVAS_API void	evas_language_reinit (void)
	Reinitialize language from the environment. More...

Detailed Description

Some functions that are handy but are not specific of canvas or objects.

Function Documentation

evas_load_error_str()

EVAS_API const char * evas_load_error_str

(

Evas_Load_Error

error

)

Converts the given Evas image load error code into a string describing it in human-readable text.

Parameters

error

the error code, a value in Evas_Load_Error.

Returns

Always returns a valid string. If the given error is not supported, "Unknown error" is returned.

Mostly evas_object_image_file_set() would be the function setting that error value afterwards, but also evas_object_image_load(), evas_object_image_save(), evas_object_image_data_get(), evas_object_image_data_convert(), evas_object_image_pixels_import() and evas_object_image_is_inside(). This function is meant to be used in conjunction with evas_object_image_load_error_get(), as in:

Example code:

   d.img1 = evas_object_image_add(d.evas);
   evas_object_image_file_set(d.img1, valid_path, NULL);
   err = evas_object_image_load_error_get(d.img1);
   if (err != EVAS_LOAD_ERROR_NONE)
     {
        fprintf(stderr, "could not load image '%s'. error string is \"%s\"\n",
                valid_path, evas_load_error_str(err));
     }
   else
     {
        printf("loaded image '%s' with succes! error string is \"%s\"\n",
               valid_path, evas_load_error_str(err));
 
        evas_object_move(d.img1, 3, 3);
        evas_object_image_fill_set(d.img1, 0, 0, WIDTH / 2, HEIGHT / 2);
        evas_object_resize(d.img1, WIDTH / 2, HEIGHT / 2);
        evas_object_show(d.img1);
 
        evas_object_focus_set(d.bg, EINA_TRUE);
        evas_object_event_callback_add(
          d.bg, EVAS_CALLBACK_KEY_DOWN, _on_keydown, NULL);
     }
 
   /* this is a border around the image above, here just to emphasize
    * its geometry */
   d.border = evas_object_image_filled_add(d.evas);
   evas_object_image_file_set(d.border, border_img_path, NULL);
   evas_object_image_border_set(d.border, 3, 3, 3, 3);
   evas_object_image_border_center_fill_set(d.border, EVAS_BORDER_FILL_NONE);
 
   evas_object_move(d.border, 0, 0);
   evas_object_resize(d.border, (WIDTH / 2) + 6, (HEIGHT / 2) + 6);
   evas_object_show(d.border);
 
   /* image loading will fail for this one -- unless one cheats and
    * puts a valid image on that path */
   d.img2 = evas_object_image_add(d.evas);
   evas_object_image_file_set(d.img2, bogus_path, NULL);
   err = evas_object_image_load_error_get(d.img2);
   if (err != EVAS_LOAD_ERROR_NONE)
     {
        fprintf(stderr, "could not load image '%s': error string is \"%s\"\n",
                bogus_path, evas_load_error_str(err));
     }
   else
     {
        evas_object_move(d.img2, WIDTH / 2, HEIGHT / 2);
        evas_object_image_fill_set(d.img2, 0, 0, WIDTH / 2, HEIGHT / 2);
        evas_object_resize(d.img2, WIDTH / 2, HEIGHT / 2);
        evas_object_show(d.img2);
     }
 
   puts(commands);
   ecore_main_loop_begin();

Here, being valid_path the path to a valid image and bogus_path a path to a file that does not exist, the two outputs of evas_load_error_str() would be (if no other errors occur): "No error on load" and "File (or file path) does not exist", respectively. See the full example.

References EVAS_LOAD_ERROR_CORRUPT_FILE, EVAS_LOAD_ERROR_DOES_NOT_EXIST, EVAS_LOAD_ERROR_GENERIC, EVAS_LOAD_ERROR_NONE, EVAS_LOAD_ERROR_PERMISSION_DENIED, EVAS_LOAD_ERROR_RESOURCE_ALLOCATION_FAILED, and EVAS_LOAD_ERROR_UNKNOWN_FORMAT.

Referenced by elm_image_memfile_set().

evas_color_hsv_to_rgb()

EVAS_API void evas_color_hsv_to_rgb	(	float	h,
		float	s,
		float	v,
		int *	r,
		int *	g,
		int *	b
	)

Convert a given color from HSV to RGB format.

Parameters

h	The Hue component of the color.
s	The Saturation component of the color.
v	The Value component of the color.
r	The Red component of the color.
g	The Green component of the color.
b	The Blue component of the color.

This function converts a given color in HSV color format to RGB color format.

evas_color_rgb_to_hsv()

EVAS_API void evas_color_rgb_to_hsv	(	int	r,
		int	g,
		int	b,
		float *	h,
		float *	s,
		float *	v
	)

Convert a given color from RGB to HSV format.

Parameters

r	The Red component of the color.
g	The Green component of the color.
b	The Blue component of the color.
h	The Hue component of the color.
s	The Saturation component of the color.
v	The Value component of the color.

This function converts a given color in RGB color format to HSV color format.

evas_color_argb_premul()

EVAS_API void evas_color_argb_premul	(	int	a,
		int *	r,
		int *	g,
		int *	b
	)

Pre-multiplies a rgb triplet by an alpha factor.

Parameters

a	The alpha factor.
r	The Red component of the color.
g	The Green component of the color.
b	The Blue component of the color.

This function pre-multiplies a given rgb triplet by an alpha factor. Alpha factor is used to define transparency.

evas_color_argb_unpremul()

EVAS_API void evas_color_argb_unpremul	(	int	a,
		int *	r,
		int *	g,
		int *	b
	)

Undo pre-multiplication of a rgb triplet by an alpha factor.

Parameters

a	The alpha factor.
r	The Red component of the color.
g	The Green component of the color.
b	The Blue component of the color.

This function undoes pre-multiplication a given rbg triplet by an alpha factor. Alpha factor is used to define transparency.

See also

evas_color_argb_premul().

evas_data_argb_premul()

EVAS_API void evas_data_argb_premul	(	unsigned int *	data,
		unsigned int	len
	)

Pre-multiplies data by an alpha factor.

Parameters

data	The data value.
len	The length value.

This function pre-multiplies a given data by an alpha factor. Alpha factor is used to define transparency.

evas_data_argb_unpremul()

EVAS_API void evas_data_argb_unpremul	(	unsigned int *	data,
		unsigned int	len
	)

Undo pre-multiplication data by an alpha factor.

Parameters

data	The data value.
len	The length value.

This function undoes pre-multiplication of a given data by an alpha factor. Alpha factor is used to define transparency.

evas_string_char_next_get()

EVAS_API int evas_string_char_next_get	(	const char *	str,
		int	pos,
		int *	decoded
	)

Gets the next character in the string.

Given the UTF-8 string in str, and starting byte position in pos, this function will place in decoded the decoded code point at pos and return the byte index for the next character in the string.

The only boundary check done is that pos must be >= 0. Other than that, no checks are performed, so passing an index value that's not within the length of the string will result in undefined behavior.

Parameters

str	The UTF-8 string
pos	The byte index where to start
decoded	Address where to store the decoded code point. Optional.

Returns

The byte index of the next character

References eina_unicode_utf8_next_get().

Referenced by elm_entry_filter_accept_set().

evas_string_char_prev_get()

EVAS_API int evas_string_char_prev_get	(	const char *	str,
		int	pos,
		int *	decoded
	)

Gets the previous character in the string.

Given the UTF-8 string in str, and starting byte position in pos, this function will place in decoded the decoded code point at pos and return the byte index for the previous character in the string.

The only boundary check done is that pos must be >= 1. Other than that, no checks are performed, so passing an index value that's not within the length of the string will result in undefined behavior.

Parameters

str	The UTF-8 string
pos	The byte index where to start
decoded	Address where to store the decoded code point. Optional.

Returns

The byte index of the previous character

References eina_unicode_utf8_get_prev().

evas_string_char_len_get()

EVAS_API int evas_string_char_len_get

(

const char *

str

)

Get the length in characters of the string.

Parameters

str	The string to get the length of.

Returns

The length in characters (not bytes)

References eina_unicode_utf8_get_len().

Referenced by elm_entry_filter_limit_size().

evas_language_direction_get()

EVAS_API Evas_BiDi_Direction evas_language_direction_get

(

void

)

Get language direction.

Since

1.20

evas_language_reinit()

EVAS_API void evas_language_reinit

(

void

)

Reinitialize language from the environment.

The locale can change while a process is running. This call tells evas to reload the locale from the environment like it does on start.

Since

1.18

Referenced by elm_language_set().