view test/testwin.c @ 1012:f14e3059e138

Date: Mon, 13 Dec 2004 21:28:18 -0500 From: Jonathan Atkins Subject: [SDL] SDL_SaveBMP width bugfix this fixes the pitch versus width difference that can happen (especially for 8bit and 24bit (with the exact RGBAmasks) surfaces) when you use SDL_SaveBMP. The problem was the pitch was used instead of the width, which in some cases is much wider than the screen area you really want to save...making for ugly crud on the saved image borders. This code has been tested with & without pitch overhangs...and with the right masks for 24 bit surfaces. I tested 8,15,16,24,32-0RGB,32-RGBA(with no SDL_SRCALPHA flag).
author Sam Lantinga <slouken@libsdl.org>
date Tue, 14 Dec 2004 06:20:49 +0000
parents 153f221b7d48
children be9c9c8f6d53
line wrap: on
line source


/* Bring up a window and play with it */

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#define BENCHMARK_SDL

#define NOTICE(X)	printf("%s", X);

#include "SDL.h"

void DrawPict(SDL_Surface *screen, char *bmpfile,
					int speedy, int flip, int nofade)
{
	SDL_Surface *picture;
	SDL_Rect dest, update;
	int i, centered;
	int ncolors;
	SDL_Color *colors, *cmap;

	/* Load the image into a surface */
	if ( bmpfile == NULL ) {
		bmpfile = "sample.bmp";		/* Sample image */
	}
fprintf(stderr, "Loading picture: %s\n", bmpfile);
	picture = SDL_LoadBMP(bmpfile);
	if ( picture == NULL ) {
		fprintf(stderr, "Couldn't load %s: %s\n", bmpfile,
							SDL_GetError());
		return;
	}

	/* Set the display colors -- on a hicolor display this is a no-op */
	if ( picture->format->palette ) {
		ncolors = picture->format->palette->ncolors;
		colors  = (SDL_Color *)malloc(ncolors*sizeof(SDL_Color));
		cmap    = (SDL_Color *)malloc(ncolors*sizeof(SDL_Color));
		memcpy(colors, picture->format->palette->colors,
						ncolors*sizeof(SDL_Color));
	} else {
		int       r, g, b;

		/* Allocate 256 color palette */
		ncolors = 256;
		colors  = (SDL_Color *)malloc(ncolors*sizeof(SDL_Color));
		cmap    = (SDL_Color *)malloc(ncolors*sizeof(SDL_Color));

		/* Set a 3,3,2 color cube */
		for ( r=0; r<8; ++r ) {
			for ( g=0; g<8; ++g ) {
				for ( b=0; b<4; ++b ) {
					i = ((r<<5)|(g<<2)|b);
					colors[i].r = r<<5;
					colors[i].g = g<<5;
					colors[i].b = b<<6;
				}
			}
		}
	}
NOTICE("testwin: setting colors\n");
	if ( ! SDL_SetColors(screen, colors, 0, ncolors) &&
				(screen->format->palette != NULL) ) {
		fprintf(stderr,
"Warning: Couldn't set all of the colors, but SDL will map the image\n"
"         (colormap fading will suffer - try the -warp option)\n"
		);
	}

	/* Set the screen to black (not really necessary) */
	if ( SDL_LockSurface(screen) == 0 ) {
		Uint32 black;
		Uint8 *pixels;

		black = SDL_MapRGB(screen->format, 0, 0, 0);
		pixels = (Uint8 *)screen->pixels;
		for ( i=0; i<screen->h; ++i ) {
			memset(pixels, black,
				screen->w*screen->format->BytesPerPixel);
			pixels += screen->pitch;
		}
		SDL_UnlockSurface(screen);
		SDL_UpdateRect(screen, 0, 0, 0, 0);
	}
	
	/* Display the picture */
	if ( speedy ) {
		SDL_Surface *displayfmt;

fprintf(stderr, "Converting picture\n");
		displayfmt = SDL_DisplayFormat(picture);
		if ( displayfmt == NULL ) {
			fprintf(stderr,
				"Couldn't convert image: %s\n", SDL_GetError());
			goto done;
		}
		SDL_FreeSurface(picture);
		picture = displayfmt;
	}
	printf("(image surface located in %s memory)\n", 
			(picture->flags&SDL_HWSURFACE) ? "video" : "system");
	centered = (screen->w - picture->w)/2;
	if ( centered < 0 ) {
		centered = 0;
	}
	dest.y = (screen->h - picture->h)/2;
	dest.w = picture->w;
	dest.h = picture->h;
NOTICE("testwin: moving image\n");
	for ( i=0; i<=centered; ++i ) {
		dest.x = i;
		update = dest;
		if ( SDL_BlitSurface(picture, NULL, screen, &update) < 0 ) {
			fprintf(stderr, "Blit failed: %s\n", SDL_GetError());
			break;
		}
		if ( flip ) {
			SDL_Flip(screen);
		} else {
			SDL_UpdateRects(screen, 1, &update);
		}
	}

#ifdef SCREENSHOT
	if ( SDL_SaveBMP(screen, "screen.bmp") < 0 )
		printf("Couldn't save screen: %s\n", SDL_GetError());
#endif

#ifndef BENCHMARK_SDL
	/* Let it sit there for a while */
	SDL_Delay(5*1000);
#endif
	/* Fade the colormap */
	if ( ! nofade ) {
		int maxstep;
		SDL_Color final;
		SDL_Color palcolors[256];
		struct {
			Sint16 r, g, b;
		} cdist[256];

NOTICE("testwin: fading out...\n");
		memcpy(cmap, colors, ncolors*sizeof(SDL_Color));
		maxstep = 32-1;
		final.r = 0xFF;
		final.g = 0x00;
		final.b = 0x00;
		memcpy(palcolors, colors, ncolors*sizeof(SDL_Color));
		for ( i=0; i<ncolors; ++i ) {
			cdist[i].r = final.r-palcolors[i].r;
			cdist[i].g = final.g-palcolors[i].g;
			cdist[i].b = final.b-palcolors[i].b;
		}
		for ( i=0; i<=maxstep/2; ++i ) {	/* halfway fade */
			int c;
			for ( c=0; c<ncolors; ++c ) {
				colors[c].r =
					palcolors[c].r+((cdist[c].r*i))/maxstep;
				colors[c].g =
					palcolors[c].g+((cdist[c].g*i))/maxstep;
				colors[c].b =
					palcolors[c].b+((cdist[c].b*i))/maxstep;
			}
			SDL_SetColors(screen, colors, 0, ncolors);
			SDL_Delay(1);
		}
		final.r = 0x00;
		final.g = 0x00;
		final.b = 0x00;
		memcpy(palcolors, colors, ncolors*sizeof(SDL_Color));
		for ( i=0; i<ncolors; ++i ) {
			cdist[i].r = final.r-palcolors[i].r;
			cdist[i].g = final.g-palcolors[i].g;
			cdist[i].b = final.b-palcolors[i].b;
		}
		maxstep /= 2;
		for ( i=0; i<=maxstep; ++i ) {		/* finish fade out */
			int c;
			for ( c=0; c<ncolors; ++c ) {
				colors[c].r =
					palcolors[c].r+((cdist[c].r*i))/maxstep;
				colors[c].g =
					palcolors[c].g+((cdist[c].g*i))/maxstep;
				colors[c].b =
					palcolors[c].b+((cdist[c].b*i))/maxstep;
			}
			SDL_SetColors(screen, colors, 0, ncolors);
			SDL_Delay(1);
		}
		for ( i=0; i<ncolors; ++i ) {
			colors[i].r = final.r;
			colors[i].g = final.g;
			colors[i].b = final.b;
		}
		SDL_SetColors(screen, colors, 0, ncolors);
NOTICE("testwin: fading in...\n");
		memcpy(palcolors, colors, ncolors*sizeof(SDL_Color));
		for ( i=0; i<ncolors; ++i ) {
			cdist[i].r = cmap[i].r-palcolors[i].r;
			cdist[i].g = cmap[i].g-palcolors[i].g;
			cdist[i].b = cmap[i].b-palcolors[i].b;
		}
		for ( i=0; i<=maxstep; ++i ) {	/* 32 step fade in */
			int c;
			for ( c=0; c<ncolors; ++c ) {
				colors[c].r =
					palcolors[c].r+((cdist[c].r*i))/maxstep;
				colors[c].g =
					palcolors[c].g+((cdist[c].g*i))/maxstep;
				colors[c].b =
					palcolors[c].b+((cdist[c].b*i))/maxstep;
			}
			SDL_SetColors(screen, colors, 0, ncolors);
			SDL_Delay(1);
		}
NOTICE("testwin: fading over\n");
	}
	
done:
	/* Free the picture and return */
	SDL_FreeSurface(picture);
	free(colors); free(cmap);
	return;
}

int main(int argc, char *argv[])
{
	SDL_Surface *screen;
	/* Options */
	int speedy, flip, nofade;
	int delay;
	int w, h;
	int desired_bpp;
	Uint32 video_flags;
#ifdef BENCHMARK_SDL
	Uint32 then, now;
#endif
	/* Set default options and check command-line */
	speedy = 0;
	flip = 0;
	nofade = 0;
	delay = 1;
	w = 640;
	h = 480;
	desired_bpp = 0;
	video_flags = 0;
	while ( argc > 1 ) {
		if ( strcmp(argv[1], "-speedy") == 0 ) {
			speedy = 1;
			argv += 1;
			argc -= 1;
		} else
		if ( strcmp(argv[1], "-nofade") == 0 ) {
			nofade = 1;
			argv += 1;
			argc -= 1;
		} else
		if ( strcmp(argv[1], "-delay") == 0 ) {
			if ( argv[2] ) {
				delay = atoi(argv[2]);
				argv += 2;
				argc -= 2;
			} else {
				fprintf(stderr,
				"The -delay option requires an argument\n");
				exit(1);
			}
		} else
		if ( strcmp(argv[1], "-width") == 0 ) {
			if ( argv[2] && ((w = atoi(argv[2])) > 0) ) {
				argv += 2;
				argc -= 2;
			} else {
				fprintf(stderr,
				"The -width option requires an argument\n");
				exit(1);
			}
		} else
		if ( strcmp(argv[1], "-height") == 0 ) {
			if ( argv[2] && ((h = atoi(argv[2])) > 0) ) {
				argv += 2;
				argc -= 2;
			} else {
				fprintf(stderr,
				"The -height option requires an argument\n");
				exit(1);
			}
		} else
		if ( strcmp(argv[1], "-bpp") == 0 ) {
			if ( argv[2] ) {
				desired_bpp = atoi(argv[2]);
				argv += 2;
				argc -= 2;
			} else {
				fprintf(stderr,
				"The -bpp option requires an argument\n");
				exit(1);
			}
		} else
		if ( strcmp(argv[1], "-warp") == 0 ) {
			video_flags |= SDL_HWPALETTE;
			argv += 1;
			argc -= 1;
		} else
		if ( strcmp(argv[1], "-hw") == 0 ) {
			video_flags |= SDL_HWSURFACE;
			argv += 1;
			argc -= 1;
		} else
		if ( strcmp(argv[1], "-flip") == 0 ) {
			video_flags |= SDL_DOUBLEBUF;
			argv += 1;
			argc -= 1;
		} else
		if ( strcmp(argv[1], "-fullscreen") == 0 ) {
			video_flags |= SDL_FULLSCREEN;
			argv += 1;
			argc -= 1;
		} else
			break;
	}

	if ( SDL_Init(SDL_INIT_VIDEO) < 0 ) {
		fprintf(stderr,
			"Couldn't initialize SDL: %s\n", SDL_GetError());
		exit(1);
	}
	atexit(SDL_Quit);			/* Clean up on exit */

	/* Initialize the display */
	screen = SDL_SetVideoMode(w, h, desired_bpp, video_flags);
	if ( screen == NULL ) {
		fprintf(stderr, "Couldn't set %dx%dx%d video mode: %s\n",
					w, h, desired_bpp, SDL_GetError());
		exit(1);
	}
	printf("Set%s %dx%dx%d mode\n",
			screen->flags & SDL_FULLSCREEN ? " fullscreen" : "",
			screen->w, screen->h, screen->format->BitsPerPixel);
	printf("(video surface located in %s memory)\n",
			(screen->flags&SDL_HWSURFACE) ? "video" : "system");
	if ( screen->flags & SDL_DOUBLEBUF ) {
		printf("Double-buffering enabled\n");
		flip = 1;
	}

	/* Set the window manager title bar */
	SDL_WM_SetCaption("SDL test window", "testwin");

	/* Do all the drawing work */
#ifdef BENCHMARK_SDL
	then = SDL_GetTicks();
	DrawPict(screen, argv[1], speedy, flip, nofade);
	now = SDL_GetTicks();
	printf("Time: %d milliseconds\n", now-then);
#else
	DrawPict(screen, argv[1], speedy, flip, nofade);
#endif
	SDL_Delay(delay*1000);
	return(0);
}