Elysian Shadows

VoidElite wrote:OK guys I'm quite new to using the delete keyword. Basically my game engine requires that the Sprite::hide() function free the 'bmp' surface(SDL) and delete the instance of the Sprite class. So that later a instance with the same name can be instantiated and hidden the same.

NOTE: this is for my show and hide system for sprites.

Here is the code for the Sprite class:

Code: Select all

#include "Content.h"

using namespace std;

#ifndef SPRITE
#define SPRITE
class Sprite{
      public:
             Sprite();
             Sprite(string file2,int x2,int y2,bool visible2);
			 void show();
			 void hide();
			 SDL_Surface *bmp;
			 string file;
			 int x;
			 int y;
			 bool visible;
};
Sprite::Sprite(){
	file="null.bmp";
	bmp=SDL_DisplayFormat(SDL_LoadBMP(file.c_str()));
	x=0;
	y=0;
	visible=false;
}
Sprite::Sprite(string file2,int x2,int y2,bool visible2){
	file=file2;
	bmp=SDL_DisplayFormat(SDL_LoadBMP(file.c_str()));
	x=x2;
	y=y2;
	visible=visible2;
}
void show(){
	SDL_BlitSurface(bmp,NULL,screen,new SDL_Rect(x,y,NULL,NULL)); //3)width 4)height
}
void hide(){
	SDL_FreeSurface(bmp);
	delete this; 
}
#endif

You should pay attention to the Sprite::hide() function:

Code: Select all

void hide(){
	SDL_FreeSurface(bmp);
	delete this; 
}

The error says that bmp is not declared in that scope and that I'm using the 'this' keyword wrong(never really used that either).

Help would be greatly appreciated.

void Sprite::show()
{
        SDL_BlitSurface(bmp,NULL,screen,new SDL_Rect(x,y,NULL,NULL)); //3)width 4)height
}
void Sprite::hide()
{
        SDL_FreeSurface(bmp);
	delete this; 
}

Rapid Cube wrote:

VoidElite wrote:OK guys I'm quite new to using the delete keyword. Basically my game engine requires that the Sprite::hide() function free the 'bmp' surface(SDL) and delete the instance of the Sprite class. So that later a instance with the same name can be instantiated and hidden the same.

NOTE: this is for my show and hide system for sprites.

Here is the code for the Sprite class:

Code: Select all

#include "Content.h"

using namespace std;

#ifndef SPRITE
#define SPRITE
class Sprite{
      public:
             Sprite();
             Sprite(string file2,int x2,int y2,bool visible2);
			 void show();
			 void hide();
			 SDL_Surface *bmp;
			 string file;
			 int x;
			 int y;
			 bool visible;
};
Sprite::Sprite(){
	file="null.bmp";
	bmp=SDL_DisplayFormat(SDL_LoadBMP(file.c_str()));
	x=0;
	y=0;
	visible=false;
}
Sprite::Sprite(string file2,int x2,int y2,bool visible2){
	file=file2;
	bmp=SDL_DisplayFormat(SDL_LoadBMP(file.c_str()));
	x=x2;
	y=y2;
	visible=visible2;
}
void show(){
	SDL_BlitSurface(bmp,NULL,screen,new SDL_Rect(x,y,NULL,NULL)); //3)width 4)height
}
void hide(){
	SDL_FreeSurface(bmp);
	delete this; 
}
#endif

You should pay attention to the Sprite::hide() function:

Code: Select all

void hide(){
	SDL_FreeSurface(bmp);
	delete this; 
}

The error says that bmp is not declared in that scope and that I'm using the 'this' keyword wrong(never really used that either).

Help would be greatly appreciated.

you implemented the show and hide functions wrong
this is how you need to do it

Code: Select all

void Sprite::show()
{
        SDL_BlitSurface(bmp,NULL,screen,new SDL_Rect(x,y,NULL,NULL)); //3)width 4)height
}
void Sprite::hide()
{
        SDL_FreeSurface(bmp);
	delete this; 
}

Rapid Cube wrote:

VoidElite wrote:OK guys I'm quite new to using the delete keyword. Basically my game engine requires that the Sprite::hide() function free the 'bmp' surface(SDL) and delete the instance of the Sprite class. So that later a instance with the same name can be instantiated and hidden the same.

NOTE: this is for my show and hide system for sprites.

Here is the code for the Sprite class:

Code: Select all

#include "Content.h"

using namespace std;

#ifndef SPRITE
#define SPRITE
class Sprite{
      public:
             Sprite();
             Sprite(string file2,int x2,int y2,bool visible2);
			 void show();
			 void hide();
			 SDL_Surface *bmp;
			 string file;
			 int x;
			 int y;
			 bool visible;
};
Sprite::Sprite(){
	file="null.bmp";
	bmp=SDL_DisplayFormat(SDL_LoadBMP(file.c_str()));
	x=0;
	y=0;
	visible=false;
}
Sprite::Sprite(string file2,int x2,int y2,bool visible2){
	file=file2;
	bmp=SDL_DisplayFormat(SDL_LoadBMP(file.c_str()));
	x=x2;
	y=y2;
	visible=visible2;
}
void show(){
	SDL_BlitSurface(bmp,NULL,screen,new SDL_Rect(x,y,NULL,NULL)); //3)width 4)height
}
void hide(){
	SDL_FreeSurface(bmp);
	delete this; 
}
#endif

You should pay attention to the Sprite::hide() function:

Code: Select all

void hide(){
	SDL_FreeSurface(bmp);
	delete this; 
}

The error says that bmp is not declared in that scope and that I'm using the 'this' keyword wrong(never really used that either).

Help would be greatly appreciated.

you implemented the show and hide functions wrong
this is how you need to do it

Code: Select all

void Sprite::show()
{
        SDL_BlitSurface(bmp,NULL,screen,new SDL_Rect(x,y,NULL,NULL)); //3)width 4)height
}
void Sprite::hide()
{
        SDL_FreeSurface(bmp);
	delete this; 
}

#ifndef CONTENT
#define CONTENT
#include <iostream>
#include "SDL\SDL.h"
#include "windows.h"
#include "Environment.h"
#include "Sprite.h"
#include "Tile.h"
#include "Map.h"
#include "World.h"
#include "Object.h"
#include "Creature.h"
#include "Npc.h"
#include "Player.h"

using namespace std;

int mapIndex=0;

SDL_Surface *screen=NULL; //SDL's screen
Sprite *sprite=new Sprite("dude.bmp",10,10,true); //test sprite
Player *player=new Player(); //Main Player
World *world=new World(); //the world
#endif