Problem Textbox
It appears the bug is that the formulae for "Right" and "Centre" are swapped. I Still haven't tested the code though!
I tried to fix that formula, but still it doesn't work. When I compile your code, I get this error:
/home/joga/Documents/projektni_zadatak/test/src/test.cpp:35: error: 'Text::Alignment' is not a class or namespace
/home/joga/Documents/projektni_zadatak/test/src/test.cpp:35: error: 'Text::Alignment' is not a class or namespace
Yes. The alignment enum does not introduce a new name space, so the correct version would be Text::Centre rather that Text::Alignment::Centre.
I've actually gone and tested it this time:
text.hpp
text.cpp
main.cpp
Not exhaustively, mind you. I threw in some very rudimentary error handling. I'm using lazy.ttf from here. I've also added a way to dynamically change the alignment, using the cursor keys.
I've actually gone and tested it this time:
text.hpp
#ifndef TEXT_HPP
#define TEXT_HPP
#include <string>
#include "SDL.h"
#include "SDL_ttf.h"
// Usually in a separate utility header
class noncopyable
{
protected:
noncopyable() {}
private:
// Deliberately private and unimplemented!
noncopyable(const noncopyable &);
noncopyable &operator=(const noncopyable &);
};
class Font : noncopyable
{
public:
Font(const std::string &font, int size);
~Font();
SDL_Surface *renderText(const std::string &text, const SDL_Color &colour) const;
bool sizeText(const std::string &text, int &width, int &height) const;
private:
TTF_Font *font;
};
class Text : noncopyable
{
public:
enum Alignment
{
Left, Right, Centre
};
Text(Font *font);
~Text();
void setText(const std::string &text);
void setAlignment(Alignment alignment);
void setColour(int r, int g, int b);
void draw(SDL_Surface *screen, int x, int y);
private:
Font *font;
SDL_Surface *message;
Alignment alignment;
SDL_Color colour;
std::string string;
};
#endif
text.cpp
#include "text.hpp"
#include <stdexcept>
Font::Font(const std::string &filename, int size)
{
font = TTF_OpenFont(filename.c_str(), size);
if(!font)
{
// Error handling
throw std::runtime_error(std::string("Failed to open font: ") + filename);
}
}
Font::~Font()
{
TTF_CloseFont(font);
}
SDL_Surface *Font::renderText(const std::string &text, const SDL_Color &colour) const
{
SDL_Surface *result = TTF_RenderText_Blended(font, text.c_str(), colour);
if(result == NULL)
{
// Error handling
throw std::runtime_error(std::string("Failed to render blended text: ") + text);
}
return result;
}
bool Font::sizeText(const std::string &text, int &width, int &height) const
{
int result = TTF_SizeText(font, text.c_str(), &width, &height);
return (result == 0);
}
Text::Text(Font *font)
:
font(font),
message(0),
alignment(alignment)
{
if(font == NULL)
{
// Error handling
throw std::runtime_error("Cannot construct Text will NULL Font");
}
colour.r = 0;
colour.g = 0;
colour.b = 0;
}
Text::~Text()
{
if(message)
{
SDL_FreeSurface(message);
}
}
Uint8 sanitiseColour(int component)
{
if(component < 0)
{
return 0;
}
else if(component > 0xff)
{
return 0xff;
}
return component;
}
void Text::setColour(int r, int g, int b)
{
colour.r = sanitiseColour(r);
colour.g = sanitiseColour(g);
colour.b = sanitiseColour(b);
}
void Text::setText(const std::string &text)
{
if(string == text)
{
return;
}
string = text;
SDL_Surface *temp = font->renderText(string, colour);
if(temp)
{
std::swap(temp, message);
SDL_FreeSurface(temp);
}
else
{
throw std::runtime_error(std::string("Failed to render text: ") + string);
// Error handling
}
}
void Text::setAlignment(Alignment alignment)
{
this->alignment = alignment;
}
void Text::draw(SDL_Surface *screen, int x, int y)
{
if(!message)
{
return;
}
int width = 0;
int height = 0;
bool result = font->sizeText(string, width, height);
if(!result)
{
// Error handling...
throw std::runtime_error(std::string("Failed to size text: ") + string);
}
SDL_Rect destination = { x, y };
switch(alignment)
{
case Left:
destination.x = x - width;
break;
case Right:
destination.x = x;
break;
case Centre:
destination.x = x - width / 2;
break;
default:
// Error handling...
throw std::runtime_error("Unknown alignment");
break;
}
if(SDL_BlitSurface(message, NULL, screen, &destination) < 0)
{
// Error handling
throw std::runtime_error("Failed to blit text");
}
}
main.cpp
#include <sstream>
#include <cstdlib>
#include "SDL.h"
#include "text.hpp"
int main( int argc, char* args[] )
{
if( SDL_Init( SDL_INIT_EVERYTHING ) < 0 )
{
return 1;
}
std::atexit(&SDL_Quit);
if( TTF_Init() < 0)
{
return 1;
}
std::atexit(&TTF_Quit);
SDL_Surface *screen = SDL_SetVideoMode( 800, 600, 0, SDL_SWSURFACE);
if(!screen)
{
return 1;
}
Font font("lazy.ttf", 16);
Text text(&font);
text.setColour(0xff, 0x00, 0x00);
text.setAlignment(Text::Centre);
text.setText("FPS: ?");
int frames = 0;
Uint32 previousTime = SDL_GetTicks();
bool running = true;
while(running)
{
SDL_Event event;
while( SDL_PollEvent(&event) )
{
if( event.type == SDL_QUIT )
{
running = false;
}
else if(event.type == SDL_KEYDOWN)
{
switch(event.key.keysym.sym)
{
case SDLK_DOWN:
case SDLK_UP:
text.setAlignment(Text::Centre);
break;
case SDLK_LEFT:
text.setAlignment(Text::Left);
break;
case SDLK_RIGHT:
text.setAlignment(Text::Right);
break;
case SDLK_ESCAPE:
running = false;
break;
}
}
}
++frames;
Uint32 now = SDL_GetTicks();
if(now - previousTime > 1000)
{
std::stringstream stream;
stream << "FPS: " << frames;
text.setText(stream.str().c_str());
frames = 0;
previousTime = now;
}
SDL_FillRect(screen, 0, 0);
text.draw(screen, screen->w / 2, screen->h / 2);
if( SDL_Flip( screen ) < 0 )
{
return 1;
}
}
return 0;
}
Not exhaustively, mind you. I threw in some very rudimentary error handling. I'm using lazy.ttf from here. I've also added a way to dynamically change the alignment, using the cursor keys.
Works like a charm. Thanks for help.
Edit: But the code you made is not and insert input textbox. I mean it does take inputs from key, but i need to get string from that textbox. Like login on websites or something like scanf function in c. I'll try use your code it and experiment with it.
Edit: But the code you made is not and insert input textbox. I mean it does take inputs from key, but i need to get string from that textbox. Like login on websites or something like scanf function in c. I'll try use your code it and experiment with it.
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