view docs/html/guidetimeexamples.html @ 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 355632dca928
children
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>Time Examples</H1
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>Time based game loop</H2
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>#define TICK_INTERVAL    30

static Uint32 next_time;

Uint32 time_left(void)
{
    Uint32 now;

    now = SDL_GetTicks();
    if(next_time &#60;= now)
        return 0;
    else
        return next_time - now;
}


/* main game loop */

    next_time = SDL_GetTicks() + TICK_INTERVAL;
    while ( game_running ) {
        update_game_state();
        SDL_Delay(time_left());
        next_time += TICK_INTERVAL;
    }&#13;</PRE
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