sdl_displaybitmap.c

SDL_DisplayBitmap一个用SDL显示bitmap的例程

#include "stdlib.h"
#include "SDL/SDL.h"

int main(int argc, char *argv[])
{
	SDL_Surface *screen;	//This pointer will reference the backbuffer
	SDL_Surface *image;	//This pointer will reference our bitmap sprite
	SDL_Surface *temp;	//This pointer will temporarily reference our bitmap sprite
	SDL_Rect src, dest;	//These rectangles will describe the source and destination regions of our blit
	
	//We must first initialize the SDL video component, and check for success
	if (SDL_Init(SDL_INIT_VIDEO) != 0) {
		printf("Unable to initialize SDL: %s\n", SDL_GetError());
		return 1;
	}
	
	//When this program exits, SDL_Quit must be called
	atexit(SDL_Quit);
	
	//Set the video mode to fullscreen 640x480 with 16bit colour and double-buffering
	screen = SDL_SetVideoMode(640, 480, 16, SDL_DOUBLEBUF | SDL_FULLSCREEN);
	if (screen == NULL) {
		printf("Unable to set video mode: %s\n", SDL_GetError());
		return 1;
	}
	
	//Load the bitmap into a temporary surface, and check for success
	temp = SDL_LoadBMP("image.bmp");
	if (temp == NULL) {
		printf("Unable to load bitmap: %s\n", SDL_GetError());
		return 1;
	}
	
	//Convert the surface to the appropriate display format
	image = SDL_DisplayFormat(temp);
	
	//Release the temporary surface
	SDL_FreeSurface(temp);
	
	//Construct the source rectangle for our blit
	src.x = 0;
	src.y = 0;
	src.w = image->w;	//Use image->w to display the entire width of the image
	src.h = image->h;	//Use image->h to display the entire height of the image
	
	//Construct the destination rectangle for our blit
	dest.x = 100;		//Display the image at the (X,Y) coordinates (100,100)
	dest.y = 100;
	dest.w = image->w;	//Ensure the destination is large enough for the image's entire width/height
	dest.h = image->h;
	
	//Blit the image to the backbuffer
	SDL_BlitSurface(image, &src, screen, &dest);
	
	//Flip the backbuffer to the primary
	SDL_Flip(screen);
	
	//Wait for 2500ms (2.5 seconds) so we can see the image
	SDL_Delay(2500);
	
	//Release the surface
	SDL_FreeSurface(image);
	
	//Return success!
	return 0;
}