libretro: check for CAN_DUPE, as suggested by ToadKing

diff --git a/frontend/libretro.c b/frontend/libretro.c
index 3b366d4..0869a25 100644 (file)
--- a/frontend/libretro.c
+++ b/frontend/libretro.c
@@ -30,6 +30,7 @@ static retro_audio_sample_batch_t audio_batch_cb;
 static void *vout_buf;
 static int vout_width, vout_height;
 static int vout_doffs_old, vout_fb_dirty;
+static bool vout_can_dupe;
 
 static int samples_sent, samples_to_send;
 static int plugins_opened;
@@ -402,7 +403,8 @@ void retro_run(void)
 
        samples_to_send += 44100 / 60;
 
-       video_cb(vout_fb_dirty ? vout_buf : NULL, vout_width, vout_height, vout_width * 2);
+       video_cb((vout_fb_dirty || !vout_can_dupe) ? vout_buf : NULL,
+               vout_width, vout_height, vout_width * 2);
        vout_fb_dirty = 0;
 }
 
@@ -446,6 +448,8 @@ void retro_init(void)
        level = 1;
        environ_cb(RETRO_ENVIRONMENT_SET_PERFORMANCE_LEVEL, &level);
 
+       environ_cb(RETRO_ENVIRONMENT_GET_CAN_DUPE, &vout_can_dupe);
+
        /* Set how much slower PSX CPU runs * 100 (so that 200 is 2 times)
         * we have to do this because cache misses and some IO penalties
         * are not emulated. Warning: changing this may break compatibility. */