ex4.c

/*=========================================================================

GFX EXAMPLE CODE - #4
        "moving sprites"

Copyright (C) 2004  Rafael de Oliveira Jannone

This example's source code is Public Domain.

WARNING: The author makes no guarantees and holds no responsibility for 
any damage, injury or loss that may result from the use of this source 
code. USE IT AT YOUR OWN RISK.

Contact the author:
        by e-mail : rafael AT jannone DOT org
        homepage  : http://jannone.org/gfxlib
        ICQ UIN   : 10115284

=========================================================================*/

#include <stdio.h>
#include <math.h>
#include "gfx.h"

typedef struct {
        int x;
        int y;
} point_t;

#define MAX_POINT       256

main() {
        double  M_PI;
        double  a;
        int     c, i, l;
        point_t p[MAX_POINT];

        printf("calculating, wait...");

        M_PI = 8.0 * atan(1.0);

        // precalculate trajetory
        for (c = 0; c < MAX_POINT; c++) {
                a = (M_PI * (double)c) / (double)MAX_POINT;
                p[c].x = ((int)(100.0 * cos(a))) + (128 - 8);
                p[c].y = ((int)(80.0 * sin(a))) + (96 - 8);

                if (c & 8)
                        putch('.');
        }
        printf("done!\n");
        
        // set graphic screen
        set_color(15, 1, 1);
        set_mode(mode_2);
        set_sprite_mode(sprite_large);

        fill(MODE2_ATTR, 0xF1, MODE2_MAX);

        // create one sprite with a shape from the character table
        set_sprite_16(0, (void*)(0x1BBF + 8));

        while (!get_trigger(0)) 
                for (c = 0; c < MAX_POINT; c++) { // for each starting point
                        for (i = 0; i < 8; i++) { // set location for the 8 sprites contiguously
                                l = (c + (i << 4)) % MAX_POINT;
                                put_sprite_16(i, p[l].x, p[l].y, 0, i + 2);
                        }
                }

        set_mode(mode_0);
}

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