An concrete pixel image. More...

Data Structures
struct	hpgs_image_vtable_st
	A table of virtual function implementing `hpgs_image`. More...
struct	hpgs_image_st
	An abstract pixel image. More...
struct	hpgs_png_image_st
Functions
HPGS_API int	hpgs_image_define_color_func (hpgs_image image, hpgs_paint_color c)
static int	hpgs_image_define_color (hpgs_image image, hpgs_paint_color c)
HPGS_API int	hpgs_image_set_palette (hpgs_image image, hpgs_palette_color p, int np)
HPGS_API hpgs_png_image *	hpgs_new_png_image (int width, int height, int depth, hpgs_bool palette, hpgs_bool do_rop3)
HPGS_API int	hpgs_png_image_set_compression (hpgs_png_image *pim, int compression)
HPGS_API int	hpgs_image_set_resolution (hpgs_image *pim, double x_dpi, double y_dpi)
HPGS_API int	hpgs_image_get_data (hpgs_image _this, unsigned char data, int stride, int *depth)
static int	hpgs_image_get_pixel (const hpgs_image _this, int x, int y, hpgs_paint_color c, double *alpha)
static int	hpgs_image_put_pixel (hpgs_image _this, int x, int y, const hpgs_paint_color c, double alpha)
static int	hpgs_image_put_chunk (hpgs_image _this, int x1, int x2, int y, const hpgs_paint_color c)
static int	hpgs_image_rop3_pixel (hpgs_image _this, int x, int y, const hpgs_paint_color c, double alpha)
static int	hpgs_image_rop3_chunk (hpgs_image _this, int x1, int x2, int y, const hpgs_paint_color c)
HPGS_API int	hpgs_image_resize (hpgs_image *_this, int w, int h)
HPGS_API int	hpgs_image_clear (hpgs_image *_this)
HPGS_API int	hpgs_image_write (hpgs_image _this, const char filename)
HPGS_API int	hpgs_image_setrop3 (hpgs_image *_this, hpgs_rop3_func_t rop3)
HPGS_API int	hpgs_image_setpatcol (hpgs_image _this, const hpgs_palette_color p)
HPGS_API void	hpgs_image_destroy (hpgs_image *_this)
HPGS_API int	hpgs_image_rop3_clip (hpgs_device device, hpgs_palette_color data, const hpgs_image img, const hpgs_point ll, const hpgs_point lr, const hpgs_point ur, const hpgs_palette_color *p, hpgs_xrop3_func_t xrop3)

Detailed Description

An concrete pixel image.

The structures and functions in this group handle the creation and manipulation of rectangular pixel containers.

This structure has a public alias hpgs_png_image and implements hpgs_image. The storage format is similar to the format used by libpng, so the image may be written to png file using hpgs_png_image_write.

Function Documentation

HPGS_API int hpgs_image_clear ( hpgs_image * _this )

Clears the given image _this.

References hpgs_set_error(), and hpgs_image_st::vtable.

__inline__ int hpgs_image_define_color	(	hpgs_image *	image,
		hpgs_paint_color *	c
	)			`[static]`

Enter the supplied rgb value to the palette of an indexed image. Set the index member of c to the palette index of the RGB triplet.

If the palette is exhausted, -1 is returned.

References hpgs_image_define_color_func(), and hpgs_image_st::palette.

Referenced by hpgs_new_png_image().

HPGS_API int hpgs_image_define_color_func	(	hpgs_image *	image,
		hpgs_paint_color *	c
	)

The helper function for the inline function hpgs_image_define_color, which is actually called for indexed images.

References hpgs_set_error(), hpgs_image_st::palette, hpgs_image_st::palette_idx, and hpgs_image_st::palette_ncolors.

Referenced by hpgs_image_define_color().

HPGS_API void hpgs_image_destroy ( hpgs_image * _this )

Destroys the given image and frees all allocated resources by this image.

References hpgs_image_st::palette, hpgs_image_st::palette_idx, and hpgs_image_st::vtable.

Referenced by hpgs_destroy_reader(), and hpgs_new_paint_device().

HPGS_API int hpgs_image_get_data	(	hpgs_image *	_this,
		unsigned char **	data,
		int *	stride,
		int *	depth
	)

Gets the pixel buffer of the png image, which is needed by some backends. If the image is not a png image -1 is retuned.

If 0 is returned, *data point to the image data and *stride is the number of bytes between two consecutive scanlines of the image.

References hpgs_set_error(), and hpgs_image_st::vtable.

__inline__ int hpgs_image_get_pixel	(	const hpgs_image *	_this,
		int	x,
		int	y,
		hpgs_paint_color *	c,
		double *	alpha
	)			`[static]`

Retrieves the color and alpha value of the pixel in column x and row y.

References hpgs_image_st::vtable.

Referenced by hpgs_image_rop3_clip().

__inline__ int hpgs_image_put_chunk	(	hpgs_image *	_this,
		int	x1,
		int	x2,
		int	y,
		const hpgs_paint_color *	c
	)			`[static]`

Sets the color of all pixels in the columns x1 up to x2 in row y. The alpha value is set to 1.

References hpgs_image_st::vtable.

__inline__ int hpgs_image_put_pixel	(	hpgs_image *	_this,
		int	x,
		int	y,
		const hpgs_paint_color *	c,
		double	alpha
	)			`[static]`

Sets the color and alpha value of the pixel in column x and row y.

References hpgs_image_st::vtable.

HPGS_API int hpgs_image_resize	(	hpgs_image *	_this,
		int	w,
		int	h
	)

Resizes the given image _this to a new width w and new height h. The pixel data preserved or initialized, if the image grows.

References hpgs_set_error(), and hpgs_image_st::vtable.

__inline__ int hpgs_image_rop3_chunk	(	hpgs_image *	_this,
		int	x1,
		int	x2,
		int	y,
		const hpgs_paint_color *	c
	)			`[static]`

Sets the color of all pixels in the columns x1 up to x2 in row y. The alpha value is set to 1. This function applies a ROP3 operation, if supported by the image.

References hpgs_image_st::vtable.

HPGS_API int hpgs_image_rop3_clip	(	hpgs_device *	device,
		hpgs_palette_color *	data,
		const hpgs_image *	img,
		const hpgs_point *	ll,
		const hpgs_point *	lr,
		const hpgs_point *	ur,
		const hpgs_palette_color *	p,
		hpgs_xrop3_func_t	xrop3
	)

Sets a clip frame to the given device, which encloses all regions of the device, which are cover by the image taking into account the given ROP3 transfer function.

The argument data must contain a pointer to a two-dimensional array of raw pixels of the size of the image. This array is filled with pixel values as if the image has been painted to a white destination area using the given ROP3 function.

Return values:

0 The clip frame is empty, no operation has been performed on the output device.

1 The clip frame is not empty, the clip path has been set to the output device using clipsave/moveto/lineto/clip operations.

2 The clip frame covers the whole image, no operation has been performed on the output device.

3 The clip frame is not empty, the visible pixels have all the same color and clip path has been set to the output device using moveto/lineto/setrgbcolor/fill operations. The image does not have to be transferred by subsequent functions, the rgb color of the device has been altered. It is assumed, that the output device has the ROP function set to the same as the funciton passed in as argument xrop3.

-1 An error occured on the output device.

References hpgs_image_st::height, hpgs_clip(), hpgs_clipsave(), hpgs_closepath(), hpgs_fill(), hpgs_image_get_pixel(), hpgs_lineto(), hpgs_log(), hpgs_moveto(), hpgs_newpath(), hpgs_set_error(), hpgs_setrgbcolor(), and hpgs_image_st::width.

__inline__ int hpgs_image_rop3_pixel	(	hpgs_image *	_this,
		int	x,
		int	y,
		const hpgs_paint_color *	c,
		double	alpha
	)			`[static]`

Sets the color and alpha value of the pixel in column x and row y. This function applies a ROP3 operation, if supported by the image.

References hpgs_image_st::vtable.

HPGS_API int hpgs_image_set_palette	(	hpgs_image *	image,
		hpgs_palette_color *	p,
		int	np
	)

Sets the palette to an indexed image.

References hpgs_set_error(), hpgs_image_st::palette, hpgs_image_st::palette_idx, and hpgs_image_st::palette_ncolors.

HPGS_API int hpgs_image_set_resolution	(	hpgs_image *	_this,
		double	x_dpi,
		double	y_dpi
	)

Sets the resolution of this image in dpi. Note that for PNG images the information in the pHYs chunk is given as an integral number of pixels per meter.

References hpgs_image_st::vtable.

Referenced by hpgs_new_paint_device().

HPGS_API int hpgs_image_setpatcol	(	hpgs_image *	_this,
		const hpgs_palette_color *	p
	)

Sets the color of the pattern applied by the ROP3 operation.

References hpgs_image_st::vtable.

HPGS_API int hpgs_image_setrop3	(	hpgs_image *	_this,
		hpgs_rop3_func_t	rop3
	)

Sets the ROP3 raster operation applied by hpgs_image_put_pixel and hpgs_image_put_chunk.

References hpgs_image_st::vtable.

HPGS_API int hpgs_image_write	(	hpgs_image *	_this,
		const char *	filename
	)

Writes the given image _this to a file with the given name filename.

References hpgs_set_error(), and hpgs_image_st::vtable.

HPGS_API hpgs_png_image* hpgs_new_png_image	(	int	width,
		int	height,
		int	depth,
		hpgs_bool	palette,
		hpgs_bool	do_rop3
	)

Creates a new hpgs_png_image on the heap using the given width and height. The bit depth depth of the image is limited to 8,16, 24 or 32.

If palette is HPGS_TRUE the image uses and indexed palette and the bit depth is limited to 8.

If palette is HPGS_FALSE the folowing depth are supported:

8 contructs a greyscale image.
16 contructs a greyscale image with alpha (transparency) plane.
24 contructs an RGB image.
16 contructs an RGB image with alpha (transparency) plane.

If do_rop3 is HPGS_TRUE the image uses ROP3 raster operations. do_rop3 is ignored for indexed images. Indexed images do never support raster operations.

References hpgs_png_image_st::bytes_per_row, hpgs_png_image_st::color_type, hpgs_png_image_st::compression, hpgs_png_image_st::data, hpgs_png_image_st::depth, hpgs_image_st::height, hpgs_image_define_color(), hpgs_image_st::palette, hpgs_image_st::palette_idx, hpgs_image_st::palette_ncolors, hpgs_png_image_st::pattern_color, hpgs_png_image_st::res_x, hpgs_png_image_st::res_y, hpgs_png_image_st::rop3, hpgs_image_st::vtable, and hpgs_image_st::width.

HPGS_API int hpgs_png_image_set_compression	(	hpgs_png_image *	pim,
		int	compression
	)

Sets the compression ratio used for a png image. Returns 0, if the compression is in the interval from 1 to 9 inclusive.

If the compression is invalid, -1 is returned.

References hpgs_png_image_st::compression, and hpgs_set_error().

The public pixel image API.

Data Structures

Functions

Detailed Description

Function Documentation