I'm relatively new to C++, recently moved from C# and Java (and before that, used to work in pure Lua environment). I've been trying to solve this issue I came across, but did not succeed. Basically, I created a class named Color and added static consts as shortcuts for various colors and it is used for the text writing using allegro (I am creating my own game engine for internal use and am creating one API in C++ for all the libraries the engine uses). What happens is that when I define a color using the static const, the text does not appear, while if I use the constructor, everything works as expected. The printf() function in main_menu returns proper results in both cases, so the local variables are being set in either cases. So the problem is really with the allegro part of the "equation".
Also, if any of this is malformed, like if there are any bad practices or anything like, I would appreciate tips on how to improve it.
Thank you in advance.
color.hpp
#pragma once
#include "allegro5/color.h"
#include "onidrive/vector2.hpp"
namespace oni {
enum Align: int;
class Font;
class Color {
public:
Color(unsigned char r = 0xFF, unsigned char g = 0xFF, unsigned char b = 0xFF, unsigned char a = 0xFF);
~Color();
unsigned char r;
unsigned char g;
unsigned char b;
unsigned char a;
static const Color white;
static const Color black;
static const Color red;
static const Color green;
static const Color blue;
static const Color yellow;
static const Color magenta;
static const Color cyan;
friend void draw_text(Font *font, Color *color, Vector2 position, Align align, std::string text);
private:
ALLEGRO_COLOR color;
};
}
color.cpp
#include "onidrive/color.hpp"
#include "allegro5/allegro.h"
oni::Color::Color(unsigned char r, unsigned char g, unsigned char b, unsigned char a) : r(r), g(g), b(b), a(a) {
this->color = al_map_rgba(r, g, b, a);
}
oni::Color::~Color() {
}
const oni::Color oni::Color::white( 0xFF, 0xFF, 0xFF, 0xFF);
const oni::Color oni::Color::black( 0x00, 0x00, 0x00);
const oni::Color oni::Color::red( 0xFF, 0x00, 0x00);
const oni::Color oni::Color::green( 0x00, 0xFF, 0x00);
const oni::Color oni::Color::blue( 0x00, 0x00, 0xFF);
const oni::Color oni::Color::yellow( 0xFF, 0xFF, 0x00);
const oni::Color oni::Color::magenta(0xFF, 0x00, 0xFF);
const oni::Color oni::Color::cyan( 0x00, 0xFF, 0xFF);
main_menu.cpp
...
void MainMenu::draw_ui() {
//when this is used, compiling, text is invisible
oni::Color color = oni::Color::red;
//when this is used, compiling, text is visible, correct color, works as expected
oni::Color color = oni::Color(0xFF, 0x00, 0x00, 0xFF);
printf("color(%X, %X, %X, %X);\n", color.r, color.g, color.b, color.a);
oni::draw_text(font, &color, Vector2(32, 32), oni::ALIGN_LEFT, "Hello World");
}
...
function draw_text
void oni::draw_text(Font *font, Color *color, Vector2 position, oni::Align align, std::string text) {
al_draw_text(font->font, color->color, position.x, position.y, (int)align, text.c_str());
}
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