/* fas.c 1.1 */
/*
    Copyright 1992, 1993 O'Reilly and Associates, Inc.  Permission to
    use, copy, and modify this program is hereby granted, as long as
    this copyright notice appears in each copy of the program source
    code.
*/

#include "book_utils.h"

#define WIN_GEOM	"500x500+50+50"

/* Structure ID */
static PEXStructure	struct_id;

#define NUM_CIRCLE_SEGMENTS	40

/* This function builds an array of circle points. */
static void
circle( x_center, y_center, radius, num_segments, points )
    float	x_center;
    float	y_center;
    float	radius;
    int		num_segments;
    PEXCoord	*points;
{
    double	delta, angle;
    int		i;

    angle = 0.0;
    delta = 2 * M_PI / num_segments;
    for ( i = 0; i < num_segments; i++, angle += delta ) {
	points[i].x = x_center + radius * cos( angle );
	points[i].y = y_center + radius * sin( angle );
	points[i].z = 0.5; 
    }
}

static void
create_structure( dpy )
    Display	*dpy;
{
    PEXColor		color;
    PEXCoord		large[NUM_CIRCLE_SEGMENTS];
    PEXCoord		small[NUM_CIRCLE_SEGMENTS];
    PEXListOfCoord	contours[2];
    
    /* Build the contour list -- 2 contours. */
    contours[0].count = NUM_CIRCLE_SEGMENTS;
    contours[0].points = large;
    contours[1].count = NUM_CIRCLE_SEGMENTS;
    contours[1].points = small;
    
    /* Create the structure. */
    struct_id = PEXCreateStructure( dpy );
    
    /* Set the interior style and color. */
    PEXSetInteriorStyle( dpy, struct_id, PEXOCStore,
			 PEXInteriorStyleSolid );
    SET_COLOR( 1, 1, 1, color ); /* white */
    PEXSetSurfaceColor( dpy, struct_id, PEXOCStore,
		        PEXColorTypeRGB, &color );
    
    /* Turn edges on and set their color. */
    PEXSetSurfaceEdgeFlag( dpy, struct_id, PEXOCStore, PEXOn );
    SET_COLOR( 0, 1, 0, color ); /* green */
    PEXSetSurfaceEdgeColor( dpy, struct_id, PEXOCStore,
			    PEXColorTypeRGB, &color );
	
    /* Generate the two circles fully overlapping. */
    circle( 0.15, 0.5, 0.1, NUM_CIRCLE_SEGMENTS, large );
    circle( 0.15, 0.5, 0.04, NUM_CIRCLE_SEGMENTS, small );
    PEXFillAreaSet( dpy, struct_id, PEXOCStore, PEXShapeConvex,
		    False, PEXContourNested, 2, contours );

    /* Generate the two circles partially overlapping. */
    circle( 0.45, 0.5, 0.1, NUM_CIRCLE_SEGMENTS, large );
    circle( 0.55, 0.5, 0.04, NUM_CIRCLE_SEGMENTS, small );
    PEXFillAreaSet( dpy, struct_id, PEXOCStore, PEXShapeConvex,
		    False, PEXContourIntersecting, 2, contours );

    /* Generate the two circles not overlapping. */
    circle( 0.75, 0.5, 0.1, NUM_CIRCLE_SEGMENTS, large );
    circle( 0.92, 0.5, 0.04, NUM_CIRCLE_SEGMENTS, small );
    PEXFillAreaSet( dpy, struct_id, PEXOCStore, PEXShapeConvex,
		    False, PEXContourDisjoint, 2, contours );
}

static void
redraw( dpy, window, renderer )
    Display	*dpy;
    Window	window;
    PEXRenderer	renderer;
{
    XClearWindow( dpy, window );
    PEXRenderNetwork( dpy, window, renderer, struct_id );
    XFlush( dpy );
}

main( argc, argv )
    int		argc;
    char	*argv[];
{
    Display			*dpy;
    Window			window;
    XEvent			event;
    XVisualInfo			vis_info;
    XColor			bkgd_color;
    XStandardColormap		cmap_info;
    PEXColorApproxEntry		capx_info;
    PEXRenderer			renderer;
    PEXRendererAttributes	rattrs;
    PEXExtensionInfo		*pexinfo;
    int				done = 0;
    
    /* Open a display and initialize PEX. */
    dpy = ora_init_pex( argv, &pexinfo );
    if ( !dpy ) exit(1);
    
    /* Determine the best visual to use. */
    ora_find_best_visual( dpy, &vis_info );
    
    /* Get a standard colormap for the visual. */
    if ( !ora_get_standard_colormap( dpy, &vis_info, &cmap_info ) ) {
	fprintf ( stderr, "Cannot find a standard colormap\n" );
	exit(1);
    }
    ora_set_stdcmap_approx( &vis_info, &cmap_info, &capx_info );

    /* Create the window, giving it a gray background. */
    bkgd_color.red = bkgd_color.green = bkgd_color.blue = 0x5555;
    bkgd_color.flags = DoRed | DoGreen | DoBlue;
    window = ora_create_window( dpy, &vis_info, &cmap_info, WIN_GEOM,
			        &bkgd_color );
    
    /* Create the structure and Set up the PEX renderer. */
    if ( STRUCTURE_SPT( pexinfo ) ) {
	create_structure( dpy );
	renderer = ora_setup_renderer( dpy, window, &capx_info,
				       &rattrs );
    } else {
	fprintf( stderr, "Structures not supported.\n" );
	exit(4);
    }
    
    /* Read and respond to X events. */
    XSelectInput( dpy, window, ExposureMask | ButtonPressMask );
    while ( !done ) {
	XNextEvent( dpy, &event );
	switch ( event.type ) {
	case Expose:
	    /* Flush remaining Expose events, then redraw. */
	    while ( XCheckTypedWindowEvent( dpy, window,
					    Expose, &event ) )
		; /* empty statement */
	    redraw( dpy, window, renderer );
	    break;
	case ButtonPress:
	    done = 1;
	    break;
	}
    }

    XCloseDisplay( dpy );
    return 0;
}