Mercurial > sdl-ios-xcode
view test/testsprite.c @ 765:4c2ba6161939
Editors Note: The original patch was modified to use SDL_Delay() instead of
nanosleep because nanosleep may not be portable to all systems
using SDL with the ALSA backend. This may be a moot point with
the switch to blocking writes anyway...
Date: Sat, 27 Dec 2003 21:47:36 +0100
From: Michel Daenzer
To: Debian Bug Tracking System
Subject: [SDL] Bug#225252: [PATCH] ALSA fixes
Package: libsdl1.2debian-all
Version: 1.2.6-2
Severity: normal
Tags: patch
For SDL 1.2.6, the ALSA backend was changed to call snd_pcm_open() with
SND_PCM_NONBLOCK. That's a good idea per se, however, it causes high CPU
usage, interrupted sound and stuttering in some games here. Taking a nanosleep
whenever snd_pcm_writei() returns -EAGAIN fixes this, but I think it's more
efficient to use blocking mode for the actual sound playback. Feedback from the
SDL and ALSA lists appreciated.
The patch also fixes the default ALSA device to be used.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sun, 04 Jan 2004 15:40:50 +0000 |
parents | b14fdadd8311 |
children | be9c9c8f6d53 |
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/* Simple program: Move N sprites around on the screen as fast as possible */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <ctype.h> #include <math.h> #include <time.h> #include "SDL.h" #define DEBUG_FLIP 1 #define NUM_SPRITES 100 #define MAX_SPEED 1 SDL_Surface *sprite; int numsprites; SDL_Rect *sprite_rects; SDL_Rect *positions; SDL_Rect *velocities; int sprites_visible; Uint16 sprite_w, sprite_h; int LoadSprite(SDL_Surface *screen, char *file) { SDL_Surface *temp; /* Load the sprite image */ sprite = SDL_LoadBMP(file); if ( sprite == NULL ) { fprintf(stderr, "Couldn't load %s: %s", file, SDL_GetError()); return(-1); } /* Set transparent pixel as the pixel at (0,0) */ if ( sprite->format->palette ) { SDL_SetColorKey(sprite, (SDL_SRCCOLORKEY|SDL_RLEACCEL), *(Uint8 *)sprite->pixels); } /* Convert sprite to video format */ temp = SDL_DisplayFormat(sprite); SDL_FreeSurface(sprite); if ( temp == NULL ) { fprintf(stderr, "Couldn't convert background: %s\n", SDL_GetError()); return(-1); } sprite = temp; /* We're ready to roll. :) */ return(0); } void MoveSprites(SDL_Surface *screen, Uint32 background) { int i, nupdates; SDL_Rect area, *position, *velocity; nupdates = 0; /* Erase all the sprites if necessary */ if ( sprites_visible ) { SDL_FillRect(screen, NULL, background); } /* Move the sprite, bounce at the wall, and draw */ for ( i=0; i<numsprites; ++i ) { position = &positions[i]; velocity = &velocities[i]; position->x += velocity->x; if ( (position->x < 0) || (position->x >= (screen->w - sprite_w)) ) { velocity->x = -velocity->x; position->x += velocity->x; } position->y += velocity->y; if ( (position->y < 0) || (position->y >= (screen->h - sprite_w)) ) { velocity->y = -velocity->y; position->y += velocity->y; } /* Blit the sprite onto the screen */ area = *position; SDL_BlitSurface(sprite, NULL, screen, &area); sprite_rects[nupdates++] = area; } #if DEBUG_FLIP { if ( (screen->flags & SDL_DOUBLEBUF) == SDL_DOUBLEBUF ) { static int t = 0; Uint32 color = SDL_MapRGB (screen->format, 255, 0, 0); SDL_Rect r; r.x = (sin((float)t * 2 * 3.1459) + 1.0) / 2.0 * (screen->w-20); r.y = 0; r.w = 20; r.h = screen->h; SDL_FillRect (screen, &r, color); t+=2; } } #endif /* Update the screen! */ if ( (screen->flags & SDL_DOUBLEBUF) == SDL_DOUBLEBUF ) { SDL_Flip(screen); } else { SDL_UpdateRects(screen, nupdates, sprite_rects); } sprites_visible = 1; } /* This is a way of telling whether or not to use hardware surfaces */ Uint32 FastestFlags(Uint32 flags, int width, int height, int bpp) { const SDL_VideoInfo *info; /* Hardware acceleration is only used in fullscreen mode */ flags |= SDL_FULLSCREEN; /* Check for various video capabilities */ info = SDL_GetVideoInfo(); if ( info->blit_hw_CC && info->blit_fill ) { /* We use accelerated colorkeying and color filling */ flags |= SDL_HWSURFACE; } /* If we have enough video memory, and will use accelerated blits directly to it, then use page flipping. */ if ( (flags & SDL_HWSURFACE) == SDL_HWSURFACE ) { /* Direct hardware blitting without double-buffering causes really bad flickering. */ if ( info->video_mem*1024 > (height*width*bpp/8) ) { flags |= SDL_DOUBLEBUF; } else { flags &= ~SDL_HWSURFACE; } } /* Return the flags */ return(flags); } int main(int argc, char *argv[]) { SDL_Surface *screen; Uint8 *mem; int width, height; Uint8 video_bpp; Uint32 videoflags; Uint32 background; int i, done; SDL_Event event; Uint32 then, now, frames; /* Initialize SDL */ if ( SDL_Init(SDL_INIT_VIDEO) < 0 ) { fprintf(stderr, "Couldn't initialize SDL: %s\n",SDL_GetError()); exit(1); } atexit(SDL_Quit); numsprites = NUM_SPRITES; videoflags = SDL_SWSURFACE|SDL_ANYFORMAT; width = 640; height = 480; video_bpp = 8; while ( argc > 1 ) { --argc; if ( strcmp(argv[argc-1], "-width") == 0 ) { width = atoi(argv[argc]); --argc; } else if ( strcmp(argv[argc-1], "-height") == 0 ) { height = atoi(argv[argc]); --argc; } else if ( strcmp(argv[argc-1], "-bpp") == 0 ) { video_bpp = atoi(argv[argc]); videoflags &= ~SDL_ANYFORMAT; --argc; } else if ( strcmp(argv[argc], "-fast") == 0 ) { videoflags = FastestFlags(videoflags, width, height, video_bpp); } else if ( strcmp(argv[argc], "-hw") == 0 ) { videoflags ^= SDL_HWSURFACE; } else if ( strcmp(argv[argc], "-flip") == 0 ) { videoflags ^= SDL_DOUBLEBUF; } else if ( strcmp(argv[argc], "-fullscreen") == 0 ) { videoflags ^= SDL_FULLSCREEN; } else if ( isdigit(argv[argc][0]) ) { numsprites = atoi(argv[argc]); } else { fprintf(stderr, "Usage: %s [-bpp N] [-hw] [-flip] [-fast] [-fullscreen] [numsprites]\n", argv[0]); exit(1); } } /* Set video mode */ screen = SDL_SetVideoMode(width, height, video_bpp, videoflags); if ( ! screen ) { fprintf(stderr, "Couldn't set %dx%d video mode: %s\n", width, height, SDL_GetError()); exit(2); } /* Load the sprite */ if ( LoadSprite(screen, "icon.bmp") < 0 ) { exit(1); } /* Allocate memory for the sprite info */ mem = (Uint8 *)malloc(4*sizeof(SDL_Rect)*numsprites); if ( mem == NULL ) { SDL_FreeSurface(sprite); fprintf(stderr, "Out of memory!\n"); exit(2); } sprite_rects = (SDL_Rect *)mem; positions = sprite_rects; sprite_rects += numsprites; velocities = sprite_rects; sprite_rects += numsprites; sprite_w = sprite->w; sprite_h = sprite->h; srand(time(NULL)); for ( i=0; i<numsprites; ++i ) { positions[i].x = rand()%(screen->w - sprite_w); positions[i].y = rand()%(screen->h - sprite_h); positions[i].w = sprite->w; positions[i].h = sprite->h; velocities[i].x = 0; velocities[i].y = 0; while ( ! velocities[i].x && ! velocities[i].y ) { velocities[i].x = (rand()%(MAX_SPEED*2+1))-MAX_SPEED; velocities[i].y = (rand()%(MAX_SPEED*2+1))-MAX_SPEED; } } background = SDL_MapRGB(screen->format, 0x00, 0x00, 0x00); /* Print out information about our surfaces */ printf("Screen is at %d bits per pixel\n",screen->format->BitsPerPixel); if ( (screen->flags & SDL_HWSURFACE) == SDL_HWSURFACE ) { printf("Screen is in video memory\n"); } else { printf("Screen is in system memory\n"); } if ( (screen->flags & SDL_DOUBLEBUF) == SDL_DOUBLEBUF ) { printf("Screen has double-buffering enabled\n"); } if ( (sprite->flags & SDL_HWSURFACE) == SDL_HWSURFACE ) { printf("Sprite is in video memory\n"); } else { printf("Sprite is in system memory\n"); } /* Run a sample blit to trigger blit acceleration */ { SDL_Rect dst; dst.x = 0; dst.y = 0; dst.w = sprite->w; dst.h = sprite->h; SDL_BlitSurface(sprite, NULL, screen, &dst); SDL_FillRect(screen, &dst, background); } if ( (sprite->flags & SDL_HWACCEL) == SDL_HWACCEL ) { printf("Sprite blit uses hardware acceleration\n"); } if ( (sprite->flags & SDL_RLEACCEL) == SDL_RLEACCEL ) { printf("Sprite blit uses RLE acceleration\n"); } /* Loop, blitting sprites and waiting for a keystroke */ frames = 0; then = SDL_GetTicks(); done = 0; sprites_visible = 0; while ( !done ) { /* Check for events */ ++frames; while ( SDL_PollEvent(&event) ) { switch (event.type) { case SDL_MOUSEBUTTONDOWN: SDL_WarpMouse(screen->w/2, screen->h/2); break; case SDL_KEYDOWN: /* Any keypress quits the app... */ case SDL_QUIT: done = 1; break; default: break; } } MoveSprites(screen, background); } SDL_FreeSurface(sprite); free(mem); /* Print out some timing information */ now = SDL_GetTicks(); if ( now > then ) { printf("%2.2f frames per second\n", ((double)frames*1000)/(now-then)); } SDL_Quit(); return(0); }