trmnl_sdl/sdl_helpers.cpp

#include "sdl_helpers.h"

#include <SDL2/SDL.h>
#include <SDL2/SDL_image.h>

#include <fstream>
#include <map>
#include <utility>

using namespace std;
using nlohmann::json;

map<pair<string, int>, TTF_Font*> font_map;
string default_font_name = "font.ttf";

bool init_sdl()
{
	if (SDL_Init(SDL_INIT_VIDEO) < 0)
	{
		cout << "SDL could not initialize! SDL - " << SDL_GetError() << endl;
		return false;
	}

	if (0 != TTF_Init())
	{
		cout << "Could not init TTF! SDL - " << SDL_GetError() << endl;
		SDL_Quit();
		return false;
	}

	int img_flags = IMG_Init(IMG_INIT_JPG | IMG_INIT_PNG | IMG_INIT_TIF);
	if (img_flags != (IMG_INIT_JPG | IMG_INIT_PNG | IMG_INIT_TIF))
	{
		cout << "Could not init IMG! SDL - " << SDL_GetError() << endl;
		TTF_Quit();
		SDL_Quit();
		return false;
	}

	return true;
}

void clean_sdl()
{
	// Clean up all fonts
	for (auto it = font_map.begin(); it != font_map.end(); ++it)
	{
		TTF_CloseFont(it->second);
	}
	font_map.clear();

	IMG_Quit();
	TTF_Quit();
	SDL_Quit();
}

TTF_Font* get_font(int size, const string& filename)
{
	pair<string, int> key(filename, size);
	if (0 != font_map.count(key))
	{
		return font_map[key];
	}
	else
	{
		TTF_Font* font = TTF_OpenFont(filename.c_str(), size);
		if (nullptr != font)
		{
			font_map[key] = font;
		}
		else
		{
			cout << "Could not open font '"<< filename << "' with size " << size << endl;
		}
		return font;
	}
}

SDL_Rect surface_align(const SDL_Surface* base, const SDL_Surface* applied,
	HorizontalAlign halign, VerticalAlign valign)
{
	SDL_Rect align = {.x = 0, .y = 0, .w = 0, .h = 0};

	if ((nullptr == base) || (nullptr == applied))
	{
		return align;
	}

	switch (halign)
	{
	case HALIGN_LEFT:
		align.x = 0;
		break;

	case HALIGN_CENTER:
		align.x = base->w / 2 - applied->w / 2;
		break;

	case HALIGN_RIGHT:
		align.x = base->w - applied->w;
		break;
	}

	switch (valign)
	{
	case VALIGN_TOP:
		align.y = 0;
		break;

	case VALIGN_CENTER:
		align.y = base->h / 2 - applied->h / 2;
		break;

	case VALIGN_BOTTOM:
		align.y = base->h - applied->h;
		break;
	}

	return align;
}

bool read_config_json(json& cfg, const string& filename, ostream* log)
{
	ifstream cfg_file(filename);

	if (!cfg_file.is_open())
	{
		if (nullptr != log)
		{
			*log << "Could not open config.json" << endl;
		}
		return false;
	}

	// Parse with comments
	try
	{
		cfg = json::parse(cfg_file, nullptr, true, true);
	}
	catch (const std::exception &e)
	{
		if (nullptr != log)
		{
			*log << e.what() << endl;
		}
		return false;
	}

	return true;
}

void json_extract(const json& j, const string& key, string& out)
{
	if (j.contains(key) && j[key].is_string())
	{
		out = j[key];
	}
}

void json_extract(const nlohmann::json& j, const string& key, int& out)
{
	if (j.contains(key) && j[key].is_number_integer())
	{
		out = j[key];
	}
}

void json_extract(const nlohmann::json& j, const string& key, bool& out)
{
	if (j.contains(key) && j[key].is_boolean())
	{
		out = j[key];
	}
}

void json_extract(const json& j, const string& key, HorizontalAlign& out)
{
	if (j.contains(key))
	{
		try
		{
			out = j[key].get<HorizontalAlign>();
		}
		catch(const std::exception& e)
		{
		}
	}
}

void json_extract(const json& j, const string& key, VerticalAlign& out)
{
	if (j.contains(key))
	{
		try
		{
			out = j[key].get<VerticalAlign>();
		}
		catch(const std::exception& e)
		{
		}
	}
}

void json_extract(const json& j, const string& key, TextFit& out)
{
	if (j.contains(key))
	{
		try
		{
			out = j[key].get<TextFit>();
		}
		catch(const std::exception& e)
		{
		}
	}
}

void json_extract(const json& j, const string& key, SDL_Color& out)
{
	if (j.contains(key) && j[key].is_object())
	{
		const json& j2 = j[key];

		json_extract(j2, "r", out.r);
		json_extract(j2, "g", out.g);
		json_extract(j2, "b", out.b);
		json_extract(j2, "a", out.a);
	}
}

void json_extract(const nlohmann::json& j, const string& key, Uint8& out)
{
	if (j.contains(key) && j[key].is_number_unsigned())
	{
		out = j[key];
	}
}