HW 5

Problem 1

Flying Characters

1. Compile and run the following code.

* Put Console.c and Console.h into the current directory, and run the following commands:

gcc [file name].c Console.c -D_WINDOWS // on Windows

gcc [file name].c Console.c -D_MAC // on MacOS

2. Complete MoveChar() so that it can run as the video below

 

 

skeleton code

#include <stdio.h>
#include <string.h>
#include <ctype.h>

#include "Console.h"

#define FROM_TOP 0
#define FROM_RIGHT 1
#define FROM_BOTTOM 2
#define FROM_LEFT 3

void MoveChar(char c, int tx, int ty, int screen_width, int screen_height, int dir);

int main()
{
    int screen_width = getWindowWidth(); // get width of current console window
    int screen_height = getWindowHeight() - 3; // get height of current console window
    int cx = screen_width / 2, cy = screen_height / 2; // set initial coordinate by center of the screen

    char text[512] = "";

    clrscr();
    printf("Input a text line: ");
    fgets(text, 511, stdin);
    int len = strlen(text);
    text[--len] = 0;

    int sx = cx - len / 2;
    for(int i = 0; i < len; i++){
        if(isspace(text[i]))
            continue;

        // move the i-th character of text
        int dir = i % 4;
        MoveChar(text[i], sx + i, cy, screen_width, screen_height, dir);

        // redraw previous characters
        gotoxy(sx, cy);        
        for(int j = 0; j <= i; j++)
            putchar(text[j]);

        // if ESC is pressed, terminate
        if(kbhit() && getch() == 27)
            break;
    }

    gotoxy(1, screen_height);
    printf("Bye!\n");

    return 0;
}

void MoveChar(char c, int tx, int ty, int screen_width, int screen_height, int dir)
{
    int x = 0, y = 0;
    int dx = 0, dy = 0;

    // TO DO: set initial coordinate (x, y) and movement vector (dx, dy) according to dir
    switch(dir % 4){
    case FROM_TOP: // from top
        // initial coordinate is (tx, 1)
        x = tx;
        y = 1;

        // movement vector of LOWER direction is (0, 1) 
        dx = 0;
        dy = 1;
        break;

    case FROM_RIGHT: // from right
        // TO DO: set initial coordinate and movement vector for movement from right

        break;

    case FROM_BOTTOM: // from bottom
        // TO DO: set initial coordinate and movement vector for movement from bottom
        break;

    case FROM_LEFT: // from up
        // TO DO: set initial coordinate and movement vector for movement from left
        break;
    }

    gotoxy(x, y);
    putchar(c);

    // TO DO: move character from (x, y) to (tx, ty) using (dx, dy)
    while(x != tx || y != ty){
        // TO DO: write your code here.

        // erase previous coordinate

        // update coordinate (x, y) using (dx, dy)

        // draw character at the new coordinate


        fflush(stdout); // flush output buffer for immediate display        
        if(dir % 2 == 1)
            MySleep(25); // horizontal movement should be faster than vertical movement
        else
            MySleep(50);
    }
}

revised code

#include <stdio.h>
#include <string.h>
#include <ctype.h>

#include "Console.h"

#define FROM_TOP 0
#define FROM_RIGHT 1
#define FROM_BOTTOM 2
#define FROM_LEFT 3

void MoveChar(char c, int tx, int ty, int screen_width, int screen_height, int dir);

int main()
{
    int screen_width = getWindowWidth(); // get width of current console window
    int screen_height = getWindowHeight() - 3; // get height of current console window
    int cx = screen_width / 2, cy = screen_height / 2; // set initial coordinate by center of the screen

    char text[512] = "";

    clrscr();
    printf("Input a text line: ");
    fgets(text, 511, stdin);
    int len = strlen(text);
    text[--len] = 0;

    int sx = cx - len / 2;
    for(int i = 0; i < len; i++){
        if(isspace(text[i]))
            continue;

        // move the i-th character of text
        int dir = i % 4;
        MoveChar(text[i], sx + i, cy, screen_width, screen_height, dir);

        // redraw previous characters
        gotoxy(sx, cy);        
        for(int j = 0; j <= i; j++)
            putchar(text[j]);

        // if ESC is pressed, terminate
        if(kbhit() && getch() == 27)
            break;
    }

    gotoxy(1, screen_height);
    printf("Bye!\n");

    return 0;
}

void MoveChar(char c, int tx, int ty, int screen_width, int screen_height, int dir)
{
    int x = 0, y = 0;
    int dx = 0, dy = 0;

    // TO DO: set initial coordinate (x, y) and movement vector (dx, dy) according to dir
    switch(dir % 4){
    case FROM_TOP: // from top
        // initial coordinate is (tx, 1)
        x = tx;
        y = 1;

        // movement vector of LOWER direction is (0, 1) 
        dx = 0;
        dy = 1;

        break;

    case FROM_RIGHT: // from right
        // TO DO: set initial coordinate and movement vector for movement from right

        // initial coordinate is (screen_width, ty)
        x = screen_width;
        y = ty;

        // movement vector of LEFT direction is (-1, 0) 
        dx = -1;
        dy = 0;

        break;

    case FROM_BOTTOM: // from bottom
        // TO DO: set initial coordinate and movement vector for movement from bottom

        // initial coordinate is (tx, screen_height)
        x = tx;
        y = screen_height;

        // movement vector of UPPER direction is (0, -1) 
        dx = 0;
        dy = -1;

        break;

    case FROM_LEFT: // from up
        // TO DO: set initial coordinate and movement vector for movement from left

        // initial coordinate is (1, ty)
        x = 1;
        y = ty;

        // movement vector of RIGHT direction is (1, 0) 
        dx = 1;
        dy = 0;

        break;
    }

    gotoxy(x, y);
    putchar(c);

    // TO DO: move character from (x, y) to (tx, ty) using (dx, dy)
    while(x != tx || y != ty){
        // TO DO: write your code here.

        // erase previous coordinate
        gotoxy(x,y);
        putchar(' ');
        // update coordinate (x, y) using (dx, dy)
        x+=dx;
        y+=dy;
        // draw character at the new coordinate
        gotoxy(x,y);
        putchar(c);

        fflush(stdout); // flush output buffer for immediate display        
        if(dir % 2 == 1)
            MySleep(25); // horizontal movement should be faster than vertical movement
        else
            MySleep(50);
    }
}

 

Problem 2

Rotate text left in a box shape

 

1. Compile and run the following code.

* Put Console.c and Console.h into the current directory, and run the following commands:

gcc [file name].c Console.c -D_WINDOWS // on Windows

gcc [file name].c Console.c -D_MAC // on MacOS

2. Complete DrawBoxText(), DuplicateText(), and RotateLeft() so that it can run as the video below

 

 

skeleton code

#include <stdio.h>
#include <string.h>

#include "Console.h"

void DrawBoxText(char text[], int sx, int sy, int width, int height);
void DuplicateText(char text[], int min_len);
void RotateLeft(char text[]);

int main()
{
    int screen_width = getWindowWidth();
    int screen_height = getWindowHeight() - 3;

    gotoxy(1, 1);
    printf("screen size = %d x %d\n", screen_width, screen_height);

    char text[512] = "God loves you and has a wonderful plan for your life!";
    int box_width = 0, box_height = 0;

    clrscr();

    printf("Input text: ");
    fgets(text, 511, stdin);
    text[strlen(text) - 1] = 0;

    printf("Input box_width and box_height: ");
    scanf("%d %d", &box_width, &box_height);

    printf("Press ESC to stop.\n");

    if(box_width > screen_width)
        box_width = screen_width;
    if(box_height > screen_height)
        box_height = screen_height;

    int sx = (screen_width - box_width) / 2; 
    int sy = (screen_height - box_height) / 2; 

    DuplicateText(text, box_width * 2 + box_height * 2 - 4);

    while(1){
        DrawBoxText(text, sx, sy, box_width, box_height);
        RotateLeft(text);

        gotoxy(screen_width, 1);
        MySleep(100);

        if(kbhit() && getch() == 27)
            break;
    }

    gotoxy(1, screen_height);
    printf("Bye!\n");

    return 0;
}

void DrawBoxText(char text[], int sx, int sy, int width, int height)
{
    int i = 0, j = 0;
    int n = 0;
    int len = strlen(text);

    // TO DO: display characters along the top side (this is example)



    // display characters along the right side (this is an example.)
    for(j = 1; n < len && j < height; j++){
        gotoxy(sx + width - 1, sy + j);
        putchar(text[n++]);
    }

    // TO DO: display characters along the bottom side
    

    // TO DO: display characters along the left side


}

void DuplicateText(char text[], int min_len)
{
    int len = strlen(text);
    if(text[len - 1] != ' ')
        text[len++] = ' ';
    
    // TO DO: duplicate text multiple times until the length >= min_len
    // ex) when min_len = 25, "hello "(lenth = 6) ==> "hello hello hello hello hello "(length = 30)



    // Hint: don't forget to put the null character at the end of the string    
}

void RotateLeft(char text[])
{
    int len = strlen(text); // the length of text

    // TO DO: rotate text one step left
    // ex) "Hello " ==> "ello H"

}

revised code

#include <stdio.h>
#include <string.h>

#include "Console.h"

void DrawBoxText(char text[], int sx, int sy, int width, int height);
void DuplicateText(char text[], int min_len);
void RotateLeft(char text[]);

int main()
{
    int screen_width = getWindowWidth();
    int screen_height = getWindowHeight() - 3;

    gotoxy(1, 1);
    printf("screen size = %d x %d\n", screen_width, screen_height);

    char text[512] = "God loves you and has a wonderful plan for your life!";
    int box_width = 0, box_height = 0;

    clrscr();

    printf("Input text: ");
    fgets(text, 511, stdin);
    text[strlen(text) - 1] = 0;

    printf("Input box_width and box_height: ");
    scanf("%d %d", &box_width, &box_height);

    printf("Press ESC to stop.\n");

    if(box_width > screen_width)
        box_width = screen_width;
    if(box_height > screen_height)
        box_height = screen_height;

    int sx = (screen_width - box_width) / 2; 
    int sy = (screen_height - box_height) / 2; 

    DuplicateText(text, box_width * 2 + box_height * 2 - 4);

    while(1){
        DrawBoxText(text, sx, sy, box_width, box_height);
        RotateLeft(text);

        gotoxy(screen_width, 1);
        MySleep(100);

        if(kbhit() && getch() == 27)
            break;
    }

    gotoxy(1, screen_height);
    printf("Bye!\n");

    return 0;
}

void DrawBoxText(char text[], int sx, int sy, int width, int height)
{
    int i = 0, j = 0;
    int n = 0;
    int len = strlen(text);

    // TO DO: display characters along the top side (this is example)
    for(j = 1; n < len && j < width; j++){
        gotoxy(sx + j, sy);
        putchar(text[n++]);
    }

    // display characters along the right side (this is an example.)
    for(j = 1; n < len && j < height; j++){
        gotoxy(sx + width - 1, sy + j);
        putchar(text[n++]);
    }

    // TO DO: display characters along the bottom side
    for(j = width-2; n < len && 0 < j ; j--){
        gotoxy(sx + j, sy+height-1);
        putchar(text[n++]);
    }

    // TO DO: display characters along the left side
    for(j = height-1; n < len && 0 <= j ; j--){
        gotoxy(sx, sy+j);
        putchar(text[n++]);
    }
}

void DuplicateText(char text[], int min_len)
{
    int len = strlen(text);
    if(text[len - 1] != ' ')
        text[len++] = ' ';
    
    // TO DO: duplicate text multiple times until the length >= min_len
    // ex) when min_len = 25, "hello "(lenth = 6) ==> "hello hello hello hello hello "(length = 30)
    int cnt=0;
    if(min_len%len!=0)
        cnt=min_len/len+1;
    else    
        cnt=min_len/len;

    int idx=len; // the index where we put the duplicated text
    for(int i=0 ; i<cnt ; i++){ // duplicate 'cnt' times
        for(int j=0 ; j<len ; j++){ // get each of the letters of 'text'
            text[idx++]=text[j]; // append to 'text'
        }
    }
    text[idx]=0; // don't forget to put the null character at the end of the string    
}

void RotateLeft(char text[])
{
    int len = strlen(text); // the length of text

    // TO DO: rotate text one step left
    // ex) "Hello " ==> "ello H"
    char temp=text[0];
    for(int i=0; i<len-1; i++)
        text[i]=text[i+1];
    text[len-1]=temp;
    text[len]=0; // don't forget to put the null character at the end of the string 
}