blitting-surfaces-sdl.c

linux下的一些小游戏编程

/* Example of simple blitting with SDL. */

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

int main()
{
    SDL_Surface *screen;
    SDL_Surface *image;
    SDL_Rect src, dest;

    /* Initialize SDL's video system and check for errors. */
    if (SDL_Init(SDL_INIT_VIDEO) != 0) {
	printf("Unable to initialize SDL: %s\n", SDL_GetError());
	return 1;
    }

    /* Make sure SDL_Quit gets called when the program exits! */
    atexit(SDL_Quit);

    /* Attempt to set a 256x256 hicolor (16-bit) video mode.
       Since 256x256 is rarely a valid video mode, SDL will
       most likely emulate this resolution with a different
       video mode. */
    screen = SDL_SetVideoMode(256, 256, 16, 0);
    if (screen == NULL) {
	printf("Unable to set video mode: %s\n", SDL_GetError());
	return 1;
    }

    /* Load the bitmap file. SDL_LoadBMP returns a pointer to a
       new surface containing the loaded image. */
    image = SDL_LoadBMP("test-image.bmp");
    if (image == NULL) {
	printf("Unable to load bitmap.\n");
	return 1;
    }

    /* The SDL blitting function needs to know how much data to copy.
       We provide this with SDL_Rect structures, which define the
       source and destination rectangles. The areas should be the
       same; SDL does not currently handle image stretching. */
    src.x = 0;
    src.y = 0;
    src.w = image->w; /* copy the entire image */
    src.h = image->h;

    dest.x = 0;
    dest.y = 0;
    dest.w = image->w;
    dest.h = image->h;

    /* Draw the bitmap to the screen. We are using a hicolor video
       mode, so we don't have to worry about colormap silliness.
       It is not necessary to lock surfaces before blitting; SDL
       will handle that. */
    SDL_BlitSurface(image, &src, screen, &dest);

    /* Ask SDL to update the entire screen. */
    SDL_UpdateRect(screen, 0, 0, 0, 0);

    /* Pause for a few seconds as the viewer gasps in awe. */
    SDL_Delay(3000);

    /* Free the memory that was allocated to the bitmap. */
    SDL_FreeSurface(image);

    return 0;
}