Seven-segment_display

Seven-segment_display.c

typedef struct point {
    double x,y;
} POINT;

typedef struct ray {
    POINT p,v;
} RAY;

typedef struct polygon {
    int n;
    POINT *v;
} POLYGON;

/*
 * This function implements the Jordan-curve test.
 * It returns 1 if the point is inside the polygon,
 * and 0 if it is outside.
 */
static int pointIsInside(POINT *pt, POLYGON *poly) {
    int i, j, c = 0;
    int n = poly->n;
    POINT *v = poly->v;
    double x = pt->x;
    double y = pt->y;
    
    for (i = 0, j = n-1; i < n; j = i++) {
        /*
         * Flip a bit for each edge that:
         *   straddles the x-axis (going up or going down), and
         *   intersects the x-axis at a positive value of x.
         */
        if ((((v[i].y <= y) && (y < v[j].y)) ||
             ((v[j].y <= y) && (y < v[i].y))) &&
            (x < (v[j].x - v[i].x) * (y - v[i].y) / (v[j].y - v[i].y) + v[i].x))
            
            c = !c;
    }
    return c;
}

static void one_drawer(unsigned char *buf, unsigned x, unsigned y, unsigned w, unsigned h) {
    POINT a[6] = {
        {.x = 1, .y = 1},
        {.x = 2, .y = 0},
        {.x = 8, .y = 0},
        {.x = 9, .y = 1},
        {.x = 8, .y = 2},
        {.x = 2, .y = 2}
    };
    
    POLYGON polygon_a = {
        .n = 6,
        .v = a
    };
    
    
    POINT b[6] = {
        {.x = 9, .y = 1},
        {.x = 10,.y = 2},
        {.x = 10,.y = 8},
        {.x = 9, .y = 9},
        {.x = 8, .y = 8},
        {.x = 8, .y = 2}
    };
    
    POLYGON polygon_b = {
        .n = 6,
        .v = b
    };

    
    POINT c[6] = {
        {.x = 9, .y = 9},
        {.x = 10,.y = 10},
        {.x = 10,.y = 16},
        {.x = 9, .y = 17},
        {.x = 8, .y = 16},
        {.x = 8, .y = 10}
    };
    
    POLYGON polygon_c = {
        .n = 6,
        .v = c
    };
    
    POINT d[6] = {
        {.x = 9, .y = 17},
        {.x = 8, .y = 18},
        {.x = 2, .y = 18},
        {.x = 1, .y = 17},
        {.x = 2, .y = 16},
        {.x = 8, .y = 16}
    };
    
    POLYGON polygon_d = {
        .n = 6,
        .v = d
    };
    
    POINT e[6] = {
        {.x = 1, .y = 17},
        {.x = 0, .y = 16},
        {.x = 0, .y = 10},
        {.x = 1, .y = 9},
        {.x = 2, .y = 10},
        {.x = 2, .y = 16}
    };
    
    POLYGON polygon_e = {
        .n = 6,
        .v = e
    };

    
    POINT f[6] = {
        {.x = 1, .y = 9},
        {.x = 0, .y = 8},
        {.x = 0, .y = 2},
        {.x = 1, .y = 1},
        {.x = 2, .y = 2},
        {.x = 2, .y = 8}
    };
    
    POLYGON polygon_f = {
        .n = 6,
        .v = f
    };

    
    POINT g[6] = {
        {.x = 1, .y = 9},
        {.x = 2, .y = 8},
        {.x = 8, .y = 8},
        {.x = 9, .y = 9},
        {.x = 8, .y = 10},
        {.x = 2, .y = 10}
    };
    
    POLYGON polygon_g = {
        .n = 6,
        .v = g
    };
    
    POINT z[6] = {
        {.x = -1,.y = -1},
        {.x = -1,.y = -1},
        {.x = -1,.y = -1},
        {.x = -1,.y = -1},
        {.x = -1,.y = -1},
        {.x = -1,.y = -1}
    };
    
    POLYGON polygon_z = {
        .n = 6,
        .v = z
    };

    
    POLYGON polygons[7] = {0};
    POINT p = {.x = x, .y = y};
    int inside = 0;

    POINT temp_point[6] = {0};
    
    POLYGON temp_polygon = {
        .n = 6,
        .v = temp_point
    };
    
    char str[] = "20180909120909";
//    char str[] = "8";
    unsigned x_offset_base = 10;
    unsigned y_offset_base = 50;
    for (unsigned str_index = 0; str_index<strlen(str); ++str_index) {
        unsigned index = 0;
        switch (str[str_index]) {
            case '0':
                polygons[index++] = polygon_a;
                polygons[index++] = polygon_b;
                polygons[index++] = polygon_c;
                polygons[index++] = polygon_d;
                polygons[index++] = polygon_e;
                polygons[index++] = polygon_f;
                polygons[index++] = polygon_z;
                break;
            case '1':
                polygons[index++] = polygon_z;
                polygons[index++] = polygon_b;
                polygons[index++] = polygon_c;
                break;
            case '2':
                polygons[index++] = polygon_a;
                polygons[index++] = polygon_b;
                polygons[index++] = polygon_z;
                polygons[index++] = polygon_d;
                polygons[index++] = polygon_e;
                polygons[index++] = polygon_z;
                polygons[index++] = polygon_g;
                break;
            case '3':
                polygons[index++] = polygon_a;
                polygons[index++] = polygon_b;
                polygons[index++] = polygon_c;
                polygons[index++] = polygon_d;
                polygons[index++] = polygon_z;
                polygons[index++] = polygon_z;
                polygons[index++] = polygon_g;
                break;
            case '4':
                polygons[index++] = polygon_z;
                polygons[index++] = polygon_b;
                polygons[index++] = polygon_c;
                polygons[index++] = polygon_z;
                polygons[index++] = polygon_z;
                polygons[index++] = polygon_f;
                polygons[index++] = polygon_g;
                break;
            case '5':
                polygons[index++] = polygon_a;
                polygons[index++] = polygon_z;
                polygons[index++] = polygon_c;
                polygons[index++] = polygon_d;
                polygons[index++] = polygon_z;
                polygons[index++] = polygon_f;
                polygons[index++] = polygon_g;
                break;
            case '6':
                polygons[index++] = polygon_a;
                polygons[index++] = polygon_z;
                polygons[index++] = polygon_c;
                polygons[index++] = polygon_d;
                polygons[index++] = polygon_e;
                polygons[index++] = polygon_f;
                polygons[index++] = polygon_g;
                break;
            case '7':
                polygons[index++] = polygon_a;
                polygons[index++] = polygon_b;
                polygons[index++] = polygon_c;
                break;
            case '8':
                polygons[index++] = polygon_a;
                polygons[index++] = polygon_b;
                polygons[index++] = polygon_c;
                polygons[index++] = polygon_d;
                polygons[index++] = polygon_e;
                polygons[index++] = polygon_f;
                polygons[index++] = polygon_g;
                break;
            case '9':
                polygons[index++] = polygon_a;
                polygons[index++] = polygon_b;
                polygons[index++] = polygon_c;
                polygons[index++] = polygon_d;
                polygons[index++] = polygon_z;
                polygons[index++] = polygon_f;
                polygons[index++] = polygon_g;
                break;
            default:
                break;
        }
        for (unsigned i = 0; i < index; ++i) {
            for (unsigned z = 0; z < temp_polygon.n; ++z) {
                temp_point[z] = polygons[i].v[z];
            }
            for (unsigned j = 0; j < temp_polygon.n; ++j) {
                temp_polygon.v[j].x *= 2;
                temp_polygon.v[j].y *= 2;
                
                temp_polygon.v[j].x += x_offset_base + str_index * 30;
                temp_polygon.v[j].y += y_offset_base;

                if (i == 0 || i == 3 || i == 6) {
                    temp_polygon.v[j].x += 1;
                }
                if (i == 1 || i == 2) {
                    temp_polygon.v[j].x += 1 * 2;
                }
                if (i == 1 || i == 5) {
                    temp_polygon.v[j].y += 1;
                }
                if (i == 6) {
                    temp_polygon.v[j].y += 1 * 2;
                }
                if (i == 2 || i == 4) {
                    temp_polygon.v[j].y += 1 * 3;
                }
                if (i == 3) {
                    temp_polygon.v[j].y += 1 * 4;
                }
            }
            
            inside = pointIsInside(&p, &temp_polygon);
            if (inside > 0) {
                break;
            }

        }
        if (inside > 0) {
            break;
        }
    }
    if (inside > 0) {
        fill_color(buf, 0xFF, 0xFF, 0xFF);
    } else {
        fill_color(buf, 0, 0, 0);
    }

}