error: default argument given for parameter 2 - c++

Question

I am working on a class project and im getting these errors, if anyone could possibly help that would be great, im new to stack overflow so im sorry if i dont post things properly.
The error states :Shapes.cpp:35:51: error: default argument given for parameter 2 of 'bool Point::draw(Screen&, char)' [-fpermissive]
bool Point::draw(Screen& scr, char ch = Screen::FG){
#ifndef Shapes_h
#define Shapes_h
#include<bits/stdc++.h>
using namespace std;
class Screen{
friend class Shape;
private:
size_t _w, _h;
vector<vector<char> > _pix;
public:
static const char FG = '*', BG = '.';
Screen(size_t w, size_t h){
_pix.resize(_h, vector<char>(_w));
}
size_t get_w() const{ return _w;}
size_t get_h() const{ return _h;}
vector<vector<char> >& get_pix() { return _pix;}
void set_w(size_t w) { _w = w;}
void set_h(size_t h) { _h = h;}
void clear() { fill(BG); }
void fill(char c); // todo cpp file
string to_string() const;
friend std::ostream& operator<<(std::ostream& os, const Screen& scr) {
return os << scr.to_string();
};
friend class Tests; // Don't remove this line
};
// SHAPE ---------------
class Shape{
public:
virtual ~Shape() {}
virtual bool draw(Screen& scr, char ch = Screen::FG) = 0;
friend class Tests;
};
class Point : public Shape {
private:
size_t _x, _y;
public:
Point(size_t x, size_t y) : _x(x), _y(y) {}
virtual ~Point() {}
bool draw(Screen& scr, char ch = Screen::FG);
friend class Tests;
};
class Line: public Shape{
private:
size_t _x1, _y1, _x2, _y2;
static bool draw_by_x(Screen& scr, char ch, size_t x1, size_t y1, size_t x2, size_t y2){
if (x2>x1){
draw_by_x(scr, ch, x2, y2, x1, y1);
}
double dy = (double) ((double)y2-y1)/((double)x2-x1);
size_t x = x1;
size_t y = y1;
bool boo = true;
for (size_t i = x1; i <= x2; i++){
boo &= Point((size_t)x, (size_t) y).draw(scr, ch);
x++; y += dy;
}
return boo;
}
static bool draw_by_y(Screen& scr, char ch, size_t x1, size_t y1, size_t x2, size_t y2){
if (x2>x1){
draw_by_x(scr, ch, x2, y2, x1, y1);
}
double dx = (double) ((double)x2-x1)/((double)y2-y1);
size_t x = x1;
size_t y = y1;
bool boo = true;
for (size_t i = x1; i <= x2; i++){
boo &= Point((size_t)x, (size_t) y).draw(scr, ch);
x += dx; y += 1;
}
return boo;
}
public:
Line(size_t a, size_t b, size_t c, size_t d) : _x1(a), _y1(b), _x2(c), _y2(d) {}
virtual ~Line() {}
bool draw(Screen& scr, char ch = Screen::FG);
friend class Tests; // Don't remove
};
class Quadrilateral: public Shape {
private:
size_t _x1, _y1, _x2, _y2, _x3, _y3, _x4, _y4;
public:
Quadrilateral(size_t a, size_t b, size_t c, size_t d, size_t e, size_t f, size_t g, size_t h):
_x1(a), _y1(b), _x2(c), _y2(d), _x3(e), _y3(f), _x4(g), _y4(h) {}
virtual ~Quadrilateral() {}
bool draw(Screen& scr, char ch = Screen::FG);
friend class Tests; // Don't remove
};
class Upright_Rectangle : public Quadrilateral {
public:
Upright_Rectangle(size_t x1,size_t y1, size_t x2, size_t y2) :
Quadrilateral(x1,y1, x1,y2, x2,y2, x2,y1) {}
virtual ~Upright_Rectangle() {}
};
class Stick_Man : public Shape{
static const size_t DEFAULT_W = 20, DEFAULT_H = 40;
private:
size_t _x, _y, _w, _h;
vector < Shape* > _parts;
public:
Stick_Man(size_t x = 0, size_t y = 0, size_t w = DEFAULT_W, size_t h = DEFAULT_H){
}
virtual ~Stick_Man();
const std::vector<Shape *>& get_parts() const { return _parts; }
bool draw(Screen& scr, char ch = Screen::FG){
return"";
}
friend class Tests; // Don't remove
};
#endif /* Shapes_h */
HERE IS MY CPP:
#include "Shapes.h"
#include<bits/stdc++.h>
#define pb push_back
using namespace std;
void Screen::fill(char c){
for (size_t i = 0; i < _h; i++){
for (size_t j = 0; j < _w; j++){
_pix[i][j] = c;
}
}
return;
}
void Screen::clear(char c){
fill(c);
return;
}
string Screen::to_string()const{
string ans = "";
for (size_t i = _h-1; i >= 0; i--){
for (size_t j = 0; j < _w; j++){
ans += _pix[i][j];
}
ans += "\n";
}
return ans;
}
bool Point::draw(Screen& scr, char ch = Screen::FG){
if (_x < scr.get_h() && _y < scr.get_w()){
scr.get_pix()[_x][_y] = ch;
return true;
}
return false;
}
bool Line::draw(Screen& scr, char ch = Screen::FG){
if (abs(int(_x1-_x2)) > abs(int(_y1-_y2))) return draw_by_x(scr, ch, _x1, _y1, _x2, _y2);
return draw_by_y(scr, ch, _x1, _y1, _x2, _y2);
}
bool Quadrilateral::draw(Screen& scr, char ch = Screen::FG){
size_t x1, y1, x2, y2, x3, y3, x4, y4;
x1 = _x1;
x2 = _x2;
x3 = _x3;
x4 = _x4;
y1 = _y1;
y2 = _y2;
y3 = _y3;
y4 = _y4;
if ((x2-x3)==(x4-x1) && (y2-y3)==(y4-y1)){
swap(x2, x3);
swap(y2, y3);
}
else if ((x4-x3)==(x2-x1) && (y4-y3)==(y2-y1)){
swap(x4, x3);
swap(y4, y3);
}
bool boo = true;
boo &= Line(x1, y1, x2, y2).draw(scr, ch);
boo &= Line(x2, y2, x3, y3).draw(scr, ch);
boo &= Line(x3, y3, x4, y4).draw(scr, ch);
return boo;
}

Answer 1

Remove the default parameter from the definition. Instead of
bool Point::draw(Screen& scr, char ch = Screen::FG){
if (_x < scr.get_h() && _y < scr.get_w()){
scr.get_pix()[_x][_y] = ch;
return true;
}
Change it to
bool Point::draw(Screen& scr, char ch){
if (_x < scr.get_h() && _y < scr.get_w()){
scr.get_pix()[_x][_y] = ch;
return true;
}
The reason you get the error is because you've already declared and defined it the draw function within the class here
bool draw(Screen& scr, char ch = Screen::FG){
return"";
}
Change this to
bool draw(Screen& scr, char ch = Screen::FG){
}
And you won't get the redefinition error anymore.