From b726fefe5dce46ac0bf0b7d09155ba1a0760dca9 Mon Sep 17 00:00:00 2001
From: wm4 <wm4@nowhere>
Date: Thu, 12 Nov 2015 22:40:02 +0100
Subject: [PATCH] vo_opengl_cb: do not block on flipping when redrawing

Gives slightly better behavior when used with Qt. (Which tends not to
flip buffers when the window is not visible.)
---
 video/out/vo_opengl_cb.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/video/out/vo_opengl_cb.c b/video/out/vo_opengl_cb.c
index a78b6a7fb7..687b9e3528 100644
--- a/video/out/vo_opengl_cb.c
+++ b/video/out/vo_opengl_cb.c
@@ -70,6 +70,7 @@ struct mpv_opengl_cb_context {
     struct vo_frame *next_frame;    // next frame to draw
     int64_t present_count;          // incremented when next frame can be shown
     int64_t expected_flip_count;    // next vsync event for next_frame
+    bool redrawing;                 // next_frame was a redraw request
     int64_t flip_count;
     struct vo_frame *cur_frame;
     struct mp_image_params img_params;
@@ -350,6 +351,7 @@ static void draw_frame(struct vo *vo, struct vo_frame *frame)
     assert(!p->ctx->next_frame);
     p->ctx->next_frame = vo_frame_ref(frame);
     p->ctx->expected_flip_count = p->ctx->flip_count + 1;
+    p->ctx->redrawing = frame ? frame->redraw : false;
     update(p);
     pthread_mutex_unlock(&p->ctx->lock);
 }
@@ -373,6 +375,9 @@ static void flip_page(struct vo *vo)
     p->ctx->present_count += 1;
     pthread_cond_signal(&p->ctx->wakeup);
 
+    if (p->ctx->redrawing)
+        goto done; // do not block for redrawing
+
     // Wait until frame was presented
     while (p->ctx->expected_flip_count > p->ctx->flip_count) {
         // mpv_opengl_cb_report_flip() is declared as optional API.