NAME

asflip - demonstrates flipping image in 90 degree increments libAfterImage/tutorials/ASFlip

NAMEASFlip

SYNOPSIS

libAfterImage application for image rotation.

DESCRIPTION

New steps described in this tutorial are : ASFlip.1. Flip value. ASFlip.2. Rotating ASImage.

SEE ALSO

Tutorial 1: ASView - explanation of basic steps needed to use
libAfterImage and some other simple things. Tutorial 2: ASScale - image scaling basics. Tutorial 3: ASTile - image tiling and tinting. Tutorial 4: ASMerge - scaling and blending of arbitrary number of
images. Tutorial 5: ASGrad - drawing multipoint linear gradients.

SOURCE

#include "../afterbase.h" #include "../afterimage.h" #include "common.h"

void usage() {
printf( "Usage: asflip [-h]|[[-f flip]|[-m vertical] "
"[-g geom] image]");
printf( "\nWhere: image - is image filename\n");
printf( " flip - rotation angle in degrees. "
"90, 180 and 270 degrees supported\n");
printf( " geom - source image is tiled using this geometry, "
"prior to rotation\n");
printf( " vertical - 1 - mirror image in vertical direction, "
"0 - horizontal\n"); }

int main(int argc, char* argv[]) {
Display *dpy = NULL;
ASVisual *asv ;
int screen = 0 , depth = 0 ;
char *image_file = "rose512.jpg" ;
int flip = FLIP_VERTICAL;
Bool vertical = False, mirror = False ;
int tile_x, tile_y, geom_flags = 0;
unsigned int tile_width, tile_height ;
ASImage *im = NULL;
ASImage *flipped_im = NULL ;

/* see ASView.1 : */
set_application_name( argv[0] );

if( argc > 1 )
{
int i = 1 ;
if( strcmp( argv[1], "-h" ) == 0 )
{
usage();
return 0;
}
for( i = 1 ; i < argc ; i++ )
{
if( argv[i][0] == '-' && i < argc-1 )
{
switch(argv[i][1])
{
case 'm' :
mirror = True;
vertical = atoi(argv[i+1]) ;
break ;
case 'f' : /* see ASFlip.1 */
mirror = False;
flip = atoi(argv[i+1])/90 ;
break ;
case 'g' : /* see ASTile.2 : */
geom_flags = XParseGeometry( argv[i+1],
&tile_x, &tile_y,
&tile_width,
&tile_height );
break ;
}
++i ;
}else
image_file = argv[i] ;
}
}else
usage();

#ifndef X_DISPLAY_MISSING
dpy = XOpenDisplay(NULL);
_XA_WM_DELETE_WINDOW = XInternAtom( dpy, "WM_DELETE_WINDOW", False);
screen = DefaultScreen(dpy);
depth = DefaultDepth( dpy, screen ); #endif
/* see ASView.2 : */
im = file2ASImage( image_file, 0xFFFFFFFF, SCREEN_GAMMA, 0, getenv("IMAGE_PATH"), NULL );
if( im == NULL )
return 1;

/* Making sure tiling geometry is sane : */
if( !get_flags(geom_flags, XValue ) )
tile_x = 0 ;
if( !get_flags(geom_flags, YValue ) )
tile_y = 0 ;
if( !get_flags(geom_flags, WidthValue ) )
{
if( !mirror )
tile_width = (get_flags(flip,FLIP_VERTICAL))?
im->height:im->width ;
else
tile_width = im->width ;
}
if( !get_flags(geom_flags, HeightValue ) )
{
if( !mirror )
tile_height = (get_flags(flip,FLIP_VERTICAL))?
im->width:im->height;
else
tile_height = im->height ;
}
printf( "%s: tiling image \"%s\" to %dx%d%+d%+d and then "
"flipping it by %d degrees\n",
get_application_name(), image_file,
tile_width, tile_height,tile_x, tile_y, flip*90 );

/* see ASView.3 : */
asv = create_asvisual( dpy, screen, depth, NULL );

/* see ASFlip.2 : */
if( !mirror )
flipped_im = flip_asimage( asv, im,
tile_x, tile_y,
tile_width, tile_height,
flip,
ASA_ASImage, 0,
ASIMAGE_QUALITY_DEFAULT );
else
flipped_im = mirror_asimage(asv, im,
tile_x, tile_y,
tile_width, tile_height,
vertical,
ASA_ASImage, 0,
ASIMAGE_QUALITY_DEFAULT );
destroy_asimage( &im );

if( flipped_im )
{ #ifndef X_DISPLAY_MISSING
/* see ASView.4 : */
Window w = create_top_level_window( asv, DefaultRootWindow(dpy),
32, 32,
tile_width, tile_height,
1, 0, NULL,
"ASFlip", image_file );
if( w != None )
{
Pixmap p ;

XMapRaised (dpy, w);
/* see ASView.5 : */
p = asimage2pixmap( asv, DefaultRootWindow(dpy), flipped_im,
NULL, True );
destroy_asimage( &flipped_im );
/* see common.c: set_window_background_and_free() : */
p = set_window_background_and_free( w, p );
/* see common.c: wait_closedown() : */
}
wait_closedown(w);
dpy = NULL; #else
/* writing result into the file */
ASImage2file( flipped_im, NULL, "asflip.jpg", ASIT_Jpeg, NULL );
destroy_asimage( &flipped_im ); #endif
}
return 0 ; }

libAfterImage/tutorials/ASFlip.1 [6.1]

SYNOPSIS

Step 1. Flip value.

DESCRIPTION

libAfterImage provides facility for rotating images in 90 degree increments - flipping essentially. Accordingly flip parameter could have 4 values - 0, -90, -180, -270 degrees.

EXAMPLE

flip = atoi(argv[2])/90;

SEE ALSO

flip
libAfterImage/tutorials/ASFlip.2 [6.2]

SYNOPSIS

Step 2. Flipping ASImage.

DESCRIPTION

Flipping can actually be combined with offset and tiling. Original image gets tiled to supplied rectangle, and then gets rotated to requested degree.

EXAMPLE

flipped_im = flip_asimage(asv, im,
tile_x, tile_y,
tile_width, tile_height,
flip,
ASA_XImage,0,
ASIMAGE_QUALITY_DEFAULT );
destroy_asimage( &im );

NOTES

As far as we need to render rotated image right away - we set to_xim parameter to True, so that image will be rotated into XImage. Right after rotation is done - we can destroy original image.

SEE ALSO

flip_asimage()