pixmap(3)

NAME

sipp_pixmap - pixmap handling code for sipp.
sipp_bitmap - bitmap handling code for sipp.

SYNOPSIS

#include <sipp_pixmap.h>
or
#include <sipp_bitmap.h>
[g]cc [flags] files -lsipp -lm [ libraries ]

DESCRIPTION

The sipp(3) library has provisions to create an image in a

pixmap in core. The most common use of this will probably be

rendering into X bitmaps, Macintosh bitmaps or something similar

but for those who do not want to use system dependent pixmaps we

provide the Sipp_pixmap. When rendering a line image the target

is a bitmap file or a bitmap in core rather than a pixmap. To

faciliate this, we also provide a bitmap implementation, the

Sipp_bitmap.

PIXMAP

A Sipp_pixmap is defined like this:

typedef struct {

int width; /* Width of the pixmap */ int height; /* Height of the pixmap */ u_char * buffer; /* A pointer to the image.

*/

} Sipp_pixmap;

The pointer buffer is a pointer to the image where

each pixel is stored as three unsigned chars in the order red,

green blue. Thus, the buffer is 3 * width * height bytes long.

The following functions operate on a Sipp_pixmap:

Sipp_pixmap *sipp_pixmap_create(width, height)

int width;
int height;

Returns a new Sipp_pixmap with the given size. The

memory used is allocated using malloc(3).

void sipp_pixmap_destruct(pm)

Sipp_pixmap *pm;

Frees all memory associated to the Sipp_pixmap pm.

void sipp_pixmap_set_pixel(pm, col, row, red, grn, blu)

Sipp_pixmap *pm;
int col;
int row;
u_char red;
u_char grn;
u_char blu

Set the pixel at (col, row) in pixmap pm to be the

color (red, grn, blu). (0, 0) is upper left.

void sipp_pixmap_write(file, pm)

FILE *file;
Sipp_pixmap *pm

Write the pixmap pm to the open file file. The im

age is written in the Portable Pixmap format (ppm), the same for

mat sipp is using when rendering to a file.

BITMAP

A Sipp_bitmap is defined like this:

typedef struct {

int width; /* Width of the bitmap in

pixels */
int height; /* Height of the bitmap in

pixels */
int width_bytes; /* Width of the bitmap in

bytes. */
u_char * buffer; /* A pointer to the image.

*/

} Sipp_bitmap;

The pointer buffer is a pointer to the image where

each pixel is a bit in an unsigned char. If the width field is

not a multiple of 8, the last bits in the last byte of a row are

not used. The most significant bit in each byte is the leftmost

pixel. The entire buffer is width_bytes * height bytes long.

The following functions operate on a Sipp_bitmap:

Sipp_bitmap *sipp_bitmap_create(width, height)

int width;
int height;

Returns a new Sipp_bitmap with the given size. The

memory used is allocated using malloc(3).

void sipp_bitmap_destruct(bm)

Sipp_bitmap *bm;

Frees all memory associated to the Sipp_bitmap bm.

void sipp_bitmap_line(bm, col1, row1, col2, row2)

Sipp_bitmap *bm;
int col1;
int row1;
int col2;
int row2;

Draw a line from (col1, row1) to (col2, row2) in

the bitmap bm. (0, 0) is upper left.

void sipp_bitmap_write(file, bm)

FILE *file;
Sipp_bitmap *bm

Write the bitmap bm to the open file file. The im

age is written in the Portable Bitmap format (pbm), the same for

mat sipp is using when rendering a line drawing to a file.

SEE ALSO

sipp(3) - simple polygon processor, a 3d-graphics library
sipp_geometric(3) - Vector and matrix functions for the

sipp(3) library
sipp_primitives(3) - a collection of geometric primitives

for sipp.
sipp_shaders(3) - a collection of shaders for sipp.

AUTHORS

Jonas Yngvesson (jonas-y@isy.liu.se)
Inge Wallin (ingwa@isy.liu.se)

BUGS

No known bugs.

3 July , 1991

PIXMAP(3)