ebm image viewer

ebmviewer.c

#include <SDL.h>
#include <stdio.h>

#define RGB(r, g, b) (((r)<<16)|((g)<<8)|(b))

void displayImage(SDL_Surface *surface, uint8_t *image) {
	uint32_t *pixels = (uint32_t *)surface->pixels;
	uint32_t pixel;
	uint16_t raw;
	uint8_t y;
	for (int i = 0; i < 530; i++) {
		for (int j = 0; j < 400; j++) {
			raw = image[i * 400 + j];
			y = (raw >> 4);
			y = ~(y << 4 | y);
			pixel = RGB(y, y, y);
			pixels[i * 800 + j * 2] = pixel;
			y = (raw & 0x0F);
			y = ~(y << 4 | y);
			pixel = RGB(y, y, y);
			pixels[i * 800 + j * 2 + 1] = pixel;
		}
	}
}

long fileLoad(const char * filename, unsigned char * * buffer, long size = 0) {
	FILE * pFile;
	long lSize;

	pFile = fopen(filename, "rb");
	if (pFile != NULL) {
		fseek(pFile, 0, SEEK_END);
		lSize = ftell(pFile);
		rewind(pFile);
		if (size != 0)
			lSize = size;
		*buffer = (unsigned char *)malloc(lSize);
		if (buffer != NULL) {
			return fread(*buffer, 1, lSize, pFile);
		}
		fclose(pFile);
	} else {
		*buffer = (unsigned char *)malloc(size);
	}
	return 0;
}

int main(int argc, char* args[])
{
	SDL_Window* window = NULL;
	SDL_Surface* screenSurface = NULL;
	SDL_Surface* display;
	SDL_Event event;
	uint8_t* file;
	int quit = 0;
	long fileRead;

	if (argc != 2) {
		printf("Usage: SDLTest image.ebm\n");
		return 1;
	}
	if (SDL_Init(SDL_INIT_VIDEO) < 0)
	{
		printf("SDL could not initialize! SDL_Error: %s\n", SDL_GetError());
		return 1;
	}
	window = SDL_CreateWindow("SDL", SDL_WINDOWPOS_UNDEFINED, SDL_WINDOWPOS_UNDEFINED, 800, 600, SDL_WINDOW_SHOWN);
	screenSurface = SDL_GetWindowSurface(window);
	display = SDL_CreateRGBSurface(0, 800, 600, 32, 0, 0, 0, 0);
	fileRead = fileLoad(args[1], &file, 212000);
	if (fileRead != 212000) {
		printf("Error: wrong file size. Size: %d\n", fileRead);
	}
	displayImage(display, file);
	SDL_BlitSurface(display, NULL, screenSurface, NULL);
	SDL_UpdateWindowSurface(window);
	
	while (!quit) {
		while (SDL_PollEvent(&event)) {
			switch (event.type) {
			case SDL_QUIT:
				quit = 1;
				break;
			default:
				break;
			}
		}
	}

	SDL_DestroyWindow(window);
	SDL_Quit();

	return 0;
}