cairo.h

按照官方的说法：Cairo is a vector graphics library with cross-device output support. 翻译过来

typedef enum _cairo_surface_type {
    CAIRO_SURFACE_TYPE_IMAGE,
    CAIRO_SURFACE_TYPE_PDF,
    CAIRO_SURFACE_TYPE_PS,
    CAIRO_SURFACE_TYPE_XLIB,
    CAIRO_SURFACE_TYPE_XCB,
    CAIRO_SURFACE_TYPE_GLITZ,
    CAIRO_SURFACE_TYPE_QUARTZ,
    CAIRO_SURFACE_TYPE_WIN32,
    CAIRO_SURFACE_TYPE_BEOS,
    CAIRO_SURFACE_TYPE_DIRECTFB,
    CAIRO_SURFACE_TYPE_SVG
} cairo_surface_type_t;

cairo_public cairo_surface_type_t
cairo_surface_get_type (cairo_surface_t *surface);

cairo_public cairo_content_t
cairo_surface_get_content (cairo_surface_t *surface);

#if CAIRO_HAS_PNG_FUNCTIONS

cairo_public cairo_status_t
cairo_surface_write_to_png (cairo_surface_t	*surface,
			    const char		*filename);

cairo_public cairo_status_t
cairo_surface_write_to_png_stream (cairo_surface_t	*surface,
				   cairo_write_func_t	write_func,
				   void			*closure);

#endif

cairo_public void *
cairo_surface_get_user_data (cairo_surface_t		 *surface,
			     const cairo_user_data_key_t *key);

cairo_public cairo_status_t
cairo_surface_set_user_data (cairo_surface_t		 *surface,
			     const cairo_user_data_key_t *key,
			     void			 *user_data,
			     cairo_destroy_func_t	 destroy);

cairo_public void
cairo_surface_get_font_options (cairo_surface_t      *surface,
				cairo_font_options_t *options);

cairo_public void
cairo_surface_flush (cairo_surface_t *surface);

cairo_public void
cairo_surface_mark_dirty (cairo_surface_t *surface);

cairo_public void
cairo_surface_mark_dirty_rectangle (cairo_surface_t *surface,
				    int              x,
				    int              y,
				    int              width,
				    int              height);

cairo_public void
cairo_surface_set_device_offset (cairo_surface_t *surface,
				 double           x_offset,
				 double           y_offset);

cairo_public void
cairo_surface_get_device_offset (cairo_surface_t *surface,
				 double          *x_offset,
				 double          *y_offset);

cairo_public void
cairo_surface_set_fallback_resolution (cairo_surface_t	*surface,
				       double		 x_pixels_per_inch,
				       double		 y_pixels_per_inch);

/* Image-surface functions */

/**
 * cairo_format_t
 * @CAIRO_FORMAT_ARGB32: each pixel is a 32-bit quantity, with
 *   alpha in the upper 8 bits, then red, then green, then blue.
 *   The 32-bit quantities are stored native-endian. Pre-multiplied
 *   alpha is used. (That is, 50% transparent red is 0x80800000,
 *   not 0x80ff0000.)
 * @CAIRO_FORMAT_RGB24: each pixel is a 32-bit quantity, with
 *   the upper 8 bits unused. Red, Green, and Blue are stored
 *   in the remaining 24 bits in that order.
 * @CAIRO_FORMAT_A8: each pixel is a 8-bit quantity holding
 *   an alpha value.
 * @CAIRO_FORMAT_A1: each pixel is a 1-bit quantity holding
 *   an alpha value. Pixels are packed together into 32-bit
 *   quantities. The ordering of the bits matches the
 *   endianess of the platform. On a big-endian machine, the
 *   first pixel is in the uppermost bit, on a little-endian
 *   machine the first pixel is in the least-significant bit.
 * @CAIRO_FORMAT_RGB16_565: each pixel is a 16-bit quantity,
 *   with red in the upper 5 bits, then green in the next 6,
 *   then blue in the lowest 5 bits. (Since 1.2)
 *
 * #cairo_format_t is used to identify the memory format of
 * image data.
 */
typedef enum _cairo_format {
    CAIRO_FORMAT_ARGB32,
    CAIRO_FORMAT_RGB24,
    CAIRO_FORMAT_A8,
    CAIRO_FORMAT_A1,
    CAIRO_FORMAT_RGB16_565
} cairo_format_t;

cairo_public cairo_surface_t *
cairo_image_surface_create (cairo_format_t	format,
			    int			width,
			    int			height);

cairo_public cairo_surface_t *
cairo_image_surface_create_for_data (unsigned char	       *data,
				     cairo_format_t		format,
				     int			width,
				     int			height,
				     int			stride);

cairo_public unsigned char *
cairo_image_surface_get_data (cairo_surface_t *surface);

cairo_public cairo_format_t
cairo_image_surface_get_format (cairo_surface_t *surface);

cairo_public int
cairo_image_surface_get_width (cairo_surface_t *surface);

cairo_public int
cairo_image_surface_get_height (cairo_surface_t *surface);

cairo_public int
cairo_image_surface_get_stride (cairo_surface_t *surface);

#if CAIRO_HAS_PNG_FUNCTIONS

cairo_public cairo_surface_t *
cairo_image_surface_create_from_png (const char	*filename);

cairo_public cairo_surface_t *
cairo_image_surface_create_from_png_stream (cairo_read_func_t	read_func,
					    void		*closure);

#endif

/* Pattern creation functions */

cairo_public cairo_pattern_t *
cairo_pattern_create_rgb (double red, double green, double blue);

cairo_public cairo_pattern_t *
cairo_pattern_create_rgba (double red, double green, double blue,
			   double alpha);

cairo_public cairo_pattern_t *
cairo_pattern_create_for_surface (cairo_surface_t *surface);

cairo_public cairo_pattern_t *
cairo_pattern_create_linear (double x0, double y0,
			     double x1, double y1);

cairo_public cairo_pattern_t *
cairo_pattern_create_radial (double cx0, double cy0, double radius0,
			     double cx1, double cy1, double radius1);

cairo_public cairo_pattern_t *
cairo_pattern_reference (cairo_pattern_t *pattern);

cairo_public void
cairo_pattern_destroy (cairo_pattern_t *pattern);

cairo_public cairo_status_t
cairo_pattern_status (cairo_pattern_t *pattern);

/**
 * cairo_pattern_type_t
 * @CAIRO_PATTERN_TYPE_SOLID: The pattern is a solid (uniform)
 * color. It may be opaque or translucent.
 * @CAIRO_PATTERN_TYPE_SURFACE: The pattern is a based on a surface (an image).
 * @CAIRO_PATTERN_TYPE_LINEAR: The pattern is a linear gradient.
 * @CAIRO_PATTERN_TYPE_RADIAL: The pattern is a radial gradient.
 *
 * #cairo_pattern_type_t is used to describe the type of a given pattern.
 *
 * The type of a pattern is determined by the function used to create
 * it. The cairo_pattern_create_rgb() and cairo_pattern_create_rgba()
 * functions create SOLID patterns. The remaining
 * cairo_pattern_create functions map to pattern types in obvious
 * ways.
 *
 * The pattern type can be queried with cairo_pattern_get_type()
 *
 * Most cairo_pattern functions can be called with a pattern of any
 * type, (though trying to change the extend or filter for a solid
 * pattern will have no effect). A notable exception is
 * cairo_pattern_add_color_stop_rgb() and
 * cairo_pattern_add_color_stop_rgba() which must only be called with
 * gradient patterns (either LINEAR or RADIAL). Otherwise the pattern
 * will be shutdown and put into an error state.
 *
 * Since: 1.2
 */
typedef enum _cairo_pattern_type {
    CAIRO_PATTERN_TYPE_SOLID,
    CAIRO_PATTERN_TYPE_SURFACE,
    CAIRO_PATTERN_TYPE_LINEAR,
    CAIRO_PATTERN_TYPE_RADIAL
} cairo_pattern_type_t;

cairo_public cairo_pattern_type_t
cairo_pattern_get_type (cairo_pattern_t *pattern);

cairo_public void
cairo_pattern_add_color_stop_rgb (cairo_pattern_t *pattern,
				  double offset,
				  double red, double green, double blue);

cairo_public void
cairo_pattern_add_color_stop_rgba (cairo_pattern_t *pattern,
				   double offset,
				   double red, double green, double blue,
				   double alpha);

cairo_public void
cairo_pattern_set_matrix (cairo_pattern_t      *pattern,
			  const cairo_matrix_t *matrix);

cairo_public void
cairo_pattern_get_matrix (cairo_pattern_t *pattern,
			  cairo_matrix_t  *matrix);

/**
 * cairo_extend_t
 * @CAIRO_EXTEND_NONE: pixels outside of the source pattern
 *   are fully transparent
 * @CAIRO_EXTEND_REPEAT: the pattern is tiled by repeating
 * @CAIRO_EXTEND_REFLECT: the pattern is tiled by reflecting
 *   at the edges (not implemented for surface patterns currently)
 * @CAIRO_EXTEND_PAD: pixels outside of the pattern copy
 *   the closest pixel from the source (Since 1.2; not implemented
 *   for surface patterns currently)
 *
 * #cairo_extend_t is used to describe how the area outside
 * of a pattern will be drawn.
 */
typedef enum _cairo_extend {
    CAIRO_EXTEND_NONE,
    CAIRO_EXTEND_REPEAT,
    CAIRO_EXTEND_REFLECT,
    CAIRO_EXTEND_PAD
} cairo_extend_t;

cairo_public void
cairo_pattern_set_extend (cairo_pattern_t *pattern, cairo_extend_t extend);

cairo_public cairo_extend_t
cairo_pattern_get_extend (cairo_pattern_t *pattern);

typedef enum _cairo_filter {
    CAIRO_FILTER_FAST,
    CAIRO_FILTER_GOOD,
    CAIRO_FILTER_BEST,
    CAIRO_FILTER_NEAREST,
    CAIRO_FILTER_BILINEAR,
    CAIRO_FILTER_GAUSSIAN
} cairo_filter_t;

cairo_public void
cairo_pattern_set_filter (cairo_pattern_t *pattern, cairo_filter_t filter);

cairo_public cairo_filter_t
cairo_pattern_get_filter (cairo_pattern_t *pattern);

/* Matrix functions */

cairo_public void
cairo_matrix_init (cairo_matrix_t *matrix,
		   double  xx, double  yx,
		   double  xy, double  yy,
		   double  x0, double  y0);

cairo_public void
cairo_matrix_init_identity (cairo_matrix_t *matrix);

cairo_public void
cairo_matrix_init_translate (cairo_matrix_t *matrix,
			     double tx, double ty);

cairo_public void
cairo_matrix_init_scale (cairo_matrix_t *matrix,
			 double sx, double sy);

cairo_public void
cairo_matrix_init_rotate (cairo_matrix_t *matrix,
			  double radians);

cairo_public void
cairo_matrix_translate (cairo_matrix_t *matrix, double tx, double ty);

cairo_public void
cairo_matrix_scale (cairo_matrix_t *matrix, double sx, double sy);

cairo_public void
cairo_matrix_rotate (cairo_matrix_t *matrix, double radians);

cairo_public cairo_status_t
cairo_matrix_invert (cairo_matrix_t *matrix);

cairo_public void
cairo_matrix_multiply (cairo_matrix_t	    *result,
		       const cairo_matrix_t *a,
		       const cairo_matrix_t *b);

cairo_public void
cairo_matrix_transform_distance (const cairo_matrix_t *matrix,
				 double *dx, double *dy);

cairo_public void
cairo_matrix_transform_point (const cairo_matrix_t *matrix,
			      double *x, double *y);

/* Functions to be used while debugging (not intended for use in production code) */
cairo_public void
cairo_debug_reset_static_data (void);

#ifndef _CAIROINT_H_

/* Obsolete functions. These definitions exist to coerce the compiler
 * into providing a little bit of guidance with its error
 * messages. The idea is to help users port their old code without
 * having to dig through lots of documentation.
 *
 * The first set of REPLACED_BY functions is for functions whose names
 * have just been changed. So fixing these up is mechanical, (and
 * automated by means of the cairo/util/cairo-api-update script.
 *
 * The second set of DEPRECATED_BY functions is for functions where
 * the replacement is used in a different way, (ie. different
 * arguments, multiple functions instead of one, etc). Fixing these up
 * will require a bit more work on the user's part, (and hopefully we
 * can get cairo-api-update to find these and print some guiding
 * information).
 */
#define cairo_current_font_extents   cairo_current_font_extents_REPLACED_BY_cairo_font_extents
#define cairo_get_font_extents       cairo_get_font_extents_REPLACED_BY_cairo_font_extents
#define cairo_current_operator       cairo_current_operator_REPLACED_BY_cairo_get_operator
#define cairo_current_tolerance	     cairo_current_tolerance_REPLACED_BY_cairo_get_tolerance
#define cairo_current_point	     cairo_current_point_REPLACED_BY_cairo_get_current_point
#define cairo_current_fill_rule	     cairo_current_fill_rule_REPLACED_BY_cairo_get_fill_rule
#define cairo_current_line_width     cairo_current_line_width_REPLACED_BY_cairo_get_line_width
#define cairo_current_line_cap       cairo_current_line_cap_REPLACED_BY_cairo_get_line_cap
#define cairo_current_line_join      cairo_current_line_join_REPLACED_BY_cairo_get_line_join
#define cairo_current_miter_limit    cairo_current_miter_limit_REPLACED_BY_cairo_get_miter_limit
#define cairo_current_matrix         cairo_current_matrix_REPLACED_BY_cairo_get_matrix
#define cairo_current_target_surface cairo_current_target_surface_REPLACED_BY_cairo_get_target
#define cairo_get_status             cairo_get_status_REPLACED_BY_cairo_status
#define cairo_concat_matrix		 cairo_concat_matrix_REPLACED_BY_cairo_transform
#define cairo_scale_font                 cairo_scale_font_REPLACED_BY_cairo_set_font_size
#define cairo_select_font                cairo_select_font_REPLACED_BY_cairo_select_font_face
#define cairo_transform_font             cairo_transform_font_REPLACED_BY_cairo_set_font_matrix
#define cairo_transform_point		 cairo_transform_point_REPLACED_BY_cairo_user_to_device
#define cairo_transform_distance	 cairo_transform_distance_REPLACED_BY_cairo_user_to_device_distance
#define cairo_inverse_transform_point	 cairo_inverse_transform_point_REPLACED_BY_cairo_device_to_user
#define cairo_inverse_transform_distance cairo_inverse_transform_distance_REPLACED_BY_cairo_device_to_user_distance
#define cairo_init_clip			 cairo_init_clip_REPLACED_BY_cairo_reset_clip
#define cairo_surface_create_for_image	 cairo_surface_create_for_image_REPLACED_BY_cairo_image_surface_create_for_data
#define cairo_default_matrix		 cairo_default_matrix_REPLACED_BY_cairo_identity_matrix
#define cairo_matrix_set_affine		 cairo_matrix_set_affine_REPLACED_BY_cairo_matrix_init
#define cairo_matrix_set_identity	 cairo_matrix_set_identity_REPLACED_BY_cairo_matrix_init_identity
#define cairo_pattern_add_color_stop	 cairo_pattern_add_color_stop_REPLACED_BY_cairo_pattern_add_color_stop_rgba
#define cairo_set_rgb_color		 cairo_set_rgb_color_REPLACED_BY_cairo_set_source_rgb
#define cairo_set_pattern		 cairo_set_pattern_REPLACED_BY_cairo_set_source
#define cairo_xlib_surface_create_for_pixmap_with_visual	cairo_xlib_surface_create_for_pixmap_with_visual_REPLACED_BY_cairo_xlib_surface_create
#define cairo_xlib_surface_create_for_window_with_visual	cairo_xlib_surface_create_for_window_with_visual_REPLACED_BY_cairo_xlib_surface_create
#define cairo_xcb_surface_create_for_pixmap_with_visual	cairo_xcb_surface_create_for_pixmap_with_visual_REPLACED_BY_cairo_xcb_surface_create
#define cairo_xcb_surface_create_for_window_with_visual	cairo_xcb_surface_create_for_window_with_visual_REPLACED_BY_cairo_xcb_surface_create
#define cairo_ps_surface_set_dpi	cairo_ps_surface_set_dpi_REPLACED_BY_cairo_surface_set_fallback_resolution
#define cairo_pdf_surface_set_dpi	cairo_pdf_surface_set_dpi_REPLACED_BY_cairo_surface_set_fallback_resolution
#define cairo_svg_surface_set_dpi	cairo_svg_surface_set_dpi_REPLACED_BY_cairo_surface_set_fallback_resolution

#define cairo_current_path	     cairo_current_path_DEPRECATED_BY_cairo_copy_path
#define cairo_current_path_flat	     cairo_current_path_flat_DEPRECATED_BY_cairo_copy_path_flat
#define cairo_get_path		     cairo_get_path_DEPRECATED_BY_cairo_copy_path
#define cairo_get_path_flat	     cairo_get_path_flat_DEPRECATED_BY_cairo_get_path_flat
#define cairo_set_alpha		     cairo_set_alpha_DEPRECATED_BY_cairo_set_source_rgba_OR_cairo_paint_with_alpha
#define cairo_show_surface	     cairo_show_surface_DEPRECATED_BY_cairo_set_source_surface_AND_cairo_paint
#define cairo_copy		     cairo_copy_DEPRECATED_BY_cairo_create_AND_MANY_INDIVIDUAL_FUNCTIONS
#define cairo_surface_set_repeat	cairo_surface_set_repeat_DEPRECATED_BY_cairo_pattern_set_extend
#define cairo_surface_set_matrix	cairo_surface_set_matrix_DEPRECATED_BY_cairo_pattern_set_matrix
#define cairo_surface_get_matrix	cairo_surface_get_matrix_DEPRECATED_BY_cairo_pattern_get_matrix
#define cairo_surface_set_filter	cairo_surface_set_filter_DEPRECATED_BY_cairo_pattern_set_filter
#define cairo_surface_get_filter	cairo_surface_get_filter_DEPRECATED_BY_cairo_pattern_get_filter
#define cairo_matrix_create		cairo_matrix_create_DEPRECATED_BY_cairo_matrix_t
#define cairo_matrix_destroy		cairo_matrix_destroy_DEPRECATED_BY_cairo_matrix_t
#define cairo_matrix_copy		cairo_matrix_copy_DEPRECATED_BY_cairo_matrix_t
#define cairo_matrix_get_affine		cairo_matrix_get_affine_DEPRECATED_BY_cairo_matrix_t
#define cairo_set_target_surface	cairo_set_target_surface_DEPRECATED_BY_cairo_create
#define cairo_set_target_glitz		cairo_set_target_glitz_DEPRECATED_BY_cairo_glitz_surface_create
#define cairo_set_target_image		cairo_set_target_image_DEPRECATED_BY_cairo_image_surface_create_for_data
#define cairo_set_target_pdf		cairo_set_target_pdf_DEPRECATED_BY_cairo_pdf_surface_create
#define cairo_set_target_png		cairo_set_target_png_DEPRECATED_BY_cairo_surface_write_to_png
#define cairo_set_target_ps		cairo_set_target_ps_DEPRECATED_BY_cairo_ps_surface_create
#define cairo_set_target_quartz		cairo_set_target_quartz_DEPRECATED_BY_cairo_quartz_surface_create
#define cairo_set_target_win32		cairo_set_target_win32_DEPRECATED_BY_cairo_win32_surface_create
#define cairo_set_target_xcb		cairo_set_target_xcb_DEPRECATED_BY_cairo_xcb_surface_create
#define cairo_set_target_drawable	cairo_set_target_drawable_DEPRECATED_BY_cairo_xlib_surface_create
#define cairo_get_status_string		cairo_get_status_string_DEPRECATED_BY_cairo_status_AND_cairo_status_to_string
#define cairo_status_string		cairo_status_string_DEPRECATED_BY_cairo_status_AND_cairo_status_to_string

#endif

CAIRO_END_DECLS

#endif /* CAIRO_H */