view test/testerror.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 0d1b16ee0bca
children
line wrap: on
line source


/* Simple test of the SDL threading code and error handling */

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

#include "SDL.h"
#include "SDL_thread.h"

static int alive = 0;

/* Call this instead of exit(), so we can clean up SDL: atexit() is evil. */
static void
quit(int rc)
{
    SDL_Quit();
    exit(rc);
}

int SDLCALL
ThreadFunc(void *data)
{
    /* Set the child thread error string */
    SDL_SetError("Thread %s (%lu) had a problem: %s",
                 (char *) data, SDL_ThreadID(), "nevermind");
    while (alive) {
        printf("Thread '%s' is alive!\n", (char *) data);
        SDL_Delay(1 * 1000);
    }
    printf("Child thread error string: %s\n", SDL_GetError());
    return (0);
}

int
main(int argc, char *argv[])
{
    SDL_Thread *thread;

    /* Load the SDL library */
    if (SDL_Init(0) < 0) {
        fprintf(stderr, "Couldn't initialize SDL: %s\n", SDL_GetError());
        return (1);
    }

    /* Set the error value for the main thread */
    SDL_SetError("No worries");

    alive = 1;
    thread = SDL_CreateThread(ThreadFunc, "#1");
    if (thread == NULL) {
        fprintf(stderr, "Couldn't create thread: %s\n", SDL_GetError());
        quit(1);
    }
    SDL_Delay(5 * 1000);
    printf("Waiting for thread #1\n");
    alive = 0;
    SDL_WaitThread(thread, NULL);

    printf("Main thread error string: %s\n", SDL_GetError());

    SDL_Quit();
    return (0);
}