Mirai's Miscellaneous Misadventures

M46 / engines / sdl2.c

/* copyright 2022 zamfofex */
/* license: AGPLv3 or later */

#include <stdlib.h>
#include <SDL2/SDL.h>
#include <mimimi.h>

static void *mimimi_sdl2_texture(void *data, struct mimimi_image *image)
{
	static unsigned char rch[] = {0x11, 0x44, 0x77, 0x99, 0xCC, 0xFF};
	static unsigned char gch[] = {0x11, 0x33, 0x55, 0x77, 0x99, 0xBB, 0xDD, 0xFF};
	static unsigned char bch[] = {0x22, 0x55, 0x88, 0xBB, 0xEE};
	
	int x, y;
	unsigned char color;
	SDL_Texture *texture;
	SDL_Surface *surface;
	Uint32 offset;
	Uint32 *pixel;
	Uint32 r, g, b, a;
	
	surface = SDL_CreateRGBSurface(0, image->width, image->height, 32, 0xFF000000, 0x00FF0000, 0x0000FF00, 0x000000FF);
	for (x = 0 ; x < image->width ; x++)
	for (y = 0 ; y < image->height ; y++)
	{
		offset = x * 4 + y * surface->pitch;
		pixel = (Uint32 *) ((char *) surface->pixels + offset);
		
		color = image->colors[x + y * image->width];
		if (color == 0)
		{
			*pixel = 0;
		}
		else if (color < 0x10)
		{
			a = color * 0x11;
			*pixel = (a << 24) | (a << 16) | (a << 8) | 0xFF;
		}
		else
		{
			color -= 0x10;
			r = rch[(color / 40) % 6];
			g = gch[(color / 5) % 8];
			b = bch[(color / 1) % 5];
			a = 0xFF;
			*pixel = (r << 24) | (g << 16) | (b << 8) | (a << 0);
		}
	}
	
	texture = SDL_CreateTextureFromSurface(data, surface);
	
	SDL_FreeSurface(surface);
	
	return texture;
}

static void mimimi_sdl2_invalidate(void *data, void *texture)
{
	(void) data;
	SDL_DestroyTexture(texture);
}

static void mimimi_sdl2_stamp(void *data, int x, int y, void *texture)
{
	SDL_Rect rect;
	
	rect.x = x;
	rect.y = y;
	SDL_QueryTexture(texture, NULL, NULL, &rect.w, &rect.h);
	
	SDL_RenderCopy(data, texture, NULL, &rect);
}

int mimimi_sdl2(void (*start)(void *chapter, struct mimimi_engine *engine), void (*tick)(void *chapter, unsigned char left, unsigned char right), unsigned long int chapter_size)
{
	static SDL_Rect rect = {0, 0, 512, 256};
	
	SDL_Window *window;
	SDL_Renderer *renderer;
	struct mimimi_engine engine;
	void *chapter;
	Uint32 past, current, delay;
	SDL_Event event;
	unsigned char *keys;
	
	atexit(&SDL_Quit);
	
	SDL_Init(SDL_INIT_VIDEO);
	
	SDL_CreateWindowAndRenderer(rect.w, rect.h, SDL_WINDOW_RESIZABLE, &window, &renderer);
	SDL_RenderSetLogicalSize(renderer, rect.w, rect.h);
	SDL_SetWindowTitle(window, "mimimi game");
	
	engine.data = renderer;
	engine.texture = &mimimi_sdl2_texture;
	engine.invalidate = &mimimi_sdl2_invalidate;
	engine.stamp = &mimimi_sdl2_stamp;
	engine.size.width = 512;
	engine.size.height = 256;
	
	chapter = malloc(chapter_size);
	if (chapter == NULL) return 1;
	
	(*start)(chapter, &engine);
	
	past = SDL_GetTicks();
	
	for (;;)
	{
		current = SDL_GetTicks();
		delay = current - past;
		past = current;
		if (delay < 33) SDL_Delay(33 - delay);
		
		while (SDL_PollEvent(&event))
		{
			if (event.type == SDL_QUIT) return 0;
			
			if (event.type == SDL_KEYDOWN)
			{
				switch (event.key.keysym.sym)
				{
					default: continue;
					case SDLK_q: return 0;
				}
			}
		}
		
		keys = (void *) SDL_GetKeyboardState(NULL);
		
		SDL_SetRenderDrawColor(renderer, 0x00, 0x00, 0x00, 0xFF);
		SDL_RenderClear(renderer);
		SDL_SetRenderDrawColor(renderer, 0xEE, 0xEE, 0xEE, 0xFF);
		SDL_RenderFillRect(renderer, &rect);
		(*tick)(chapter, keys[SDL_SCANCODE_LEFT], keys[SDL_SCANCODE_RIGHT]);
		SDL_RenderPresent(renderer);
	}
}