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()