cscape/sdl.c

/* $Revision$ */

#include <SDL.h>
#include <stdlib.h>
#include "sdl.h"

SDL_Surface* sdl_init() {
	SDL_Surface* screen;

	screen = SDL_SetVideoMode(WIDTH, HEIGHT, 8, SDL_SWSURFACE);
	if(screen == NULL) {
		fprintf(stderr, "Unable to set video mode: %s\n", 
			SDL_GetError());
		exit(1);
	}

	return screen;
}

void sdl_putpixel(SDL_Surface *surface, int x, int y, Uint32 pixel)
{
    int bpp = surface->format->BytesPerPixel;
    /* Here p is the address to the pixel we want to set */
    Uint8 *p = (Uint8 *)surface->pixels + y * surface->pitch + x * bpp;

    switch(bpp) {
    case 1:
        *p = pixel;
        break;

    case 2:
        *(Uint16 *)p = pixel;
        break;

    case 3:
        if(SDL_BYTEORDER == SDL_BIG_ENDIAN) {
            p[0] = (pixel >> 16) & 0xff;
            p[1] = (pixel >> 8) & 0xff;
            p[2] = pixel & 0xff;
        } else {
            p[0] = pixel & 0xff;
            p[1] = (pixel >> 8) & 0xff;
            p[2] = (pixel >> 16) & 0xff;
        }
        break;

    case 4:
        *(Uint32 *)p = pixel;
        break;
    }
}