Mercurial > sdl-ios-xcode
view src/audio/android/SDL_androidaudio.c @ 5053:b5b42be9333c
Fixed bug #1026
Vittorio Giovara 2010-07-16 19:09:28 PDT
i was reading SDL_renderer_gles and i noticed that every time we there
is some gl call the gl state is modified with a couple of
glEnableClientState()/glDisableClientState.
While this is completely fine for desktops systems, this is a major
performace kill on mobile devices, right where opengles is
implemented.
Normal practice in this case is to update the glstate once, keep it
always the same and disable/enable other states only in very special
occasions.
On the web there's plenty of documentation (on the top of my head
http://developer.apple.com/iphone/library/documentation/3DDrawing/Conceptual/OpenGLES_ProgrammingGuide/Performance/Performance.html#//apple_ref/doc/uid/TP40008793-CH105-SW5
) and i personally tried this.
I modified my code and got a 10 fps boost, then modified SDL_render_gles and
shifted from 40 fps to 50 fps alone -- considering that i started from ~30fps i
got an 80% performance increase with this technique.
I have attached a dif of my changes, hope that it will be included in
mainstream.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Wed, 19 Jan 2011 23:56:16 -0800 |
parents | 8d7315668e35 |
children | 327f181542f1 |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2010 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA Sam Lantinga slouken@libsdl.org */ #include "SDL_config.h" /* Output audio to Android */ #include "SDL_audio.h" #include "../SDL_audio_c.h" #include "SDL_androidaudio.h" #include "../../SDL_android.h" #include <android/log.h> static void * audioDevice; static int AndroidAUD_OpenDevice(_THIS, const char *devname, int iscapture) { SDL_AudioFormat test_format; int valid_datatype = 0; if (iscapture) { //TODO: implement capture SDL_SetError("Capture not supported on Android"); return 0; } if (audioDevice != NULL) { SDL_SetError("Only one audio device at a time please!"); return 0; } audioDevice = this; this->hidden = SDL_malloc(sizeof(*(this->hidden))); if (!this->hidden) { SDL_OutOfMemory(); return 0; } SDL_memset(this->hidden, 0, (sizeof *this->hidden)); test_format = SDL_FirstAudioFormat(this->spec.format); while (test_format != 0) { // no "UNKNOWN" constant if ((test_format == AUDIO_U8) || (test_format == AUDIO_S16LSB)) { this->spec.format = test_format; break; } test_format = SDL_NextAudioFormat(); } if (test_format == 0) { // Didn't find a compatible format :( SDL_SetError("No compatible audio format!"); return 0; } if (this->spec.channels > 1) { this->spec.channels = 2; } else { this->spec.channels = 1; } if (this->spec.freq < 8000) { this->spec.freq = 8000; } if (this->spec.freq > 48000) { this->spec.freq = 48000; } // TODO: pass in/return a (Java) device ID, also whether we're opening for input or output this->spec.samples = Android_JNI_OpenAudioDevice(this->spec.freq, this->spec.format == AUDIO_U8 ? 0 : 1, this->spec.channels, this->spec.samples); SDL_CalculateAudioSpec(&this->spec); if (this->spec.samples == 0) { // Init failed? SDL_SetError("Java-side initialization failed!"); return 0; } return 1; } static void AndroidAUD_PlayDevice(_THIS) { Android_JNI_WriteAudioBuffer(); } static Uint8 * AndroidAUD_GetDeviceBuf(_THIS) { return Android_JNI_GetAudioBuffer(); } static void AndroidAUD_CloseDevice(_THIS) { if (this->hidden != NULL) { SDL_free(this->hidden); this->hidden = NULL; } Android_JNI_CloseAudioDevice(); if (audioDevice == this) { audioDevice = NULL; } } static int AndroidAUD_Init(SDL_AudioDriverImpl * impl) { /* Set the function pointers */ impl->OpenDevice = AndroidAUD_OpenDevice; impl->PlayDevice = AndroidAUD_PlayDevice; impl->GetDeviceBuf = AndroidAUD_GetDeviceBuf; impl->CloseDevice = AndroidAUD_CloseDevice; /* and the capabilities */ impl->ProvidesOwnCallbackThread = 1; impl->HasCaptureSupport = 0; //TODO impl->OnlyHasDefaultOutputDevice = 1; impl->OnlyHasDefaultInputDevice = 1; return 1; /* this audio target is available. */ } AudioBootStrap ANDROIDAUD_bootstrap = { "android", "SDL Android audio driver", AndroidAUD_Init, 0 /*1? */ }; /* Called by the Java code to start the audio processing on a thread */ void Android_RunAudioThread() { SDL_RunAudio(audioDevice); } /* vi: set ts=4 sw=4 expandtab: */