asflip(1)

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

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()