From df4d15be7b16f5b83e05dcbca7ccc17567839c1e Mon Sep 17 00:00:00 2001
From: Stefano Pigozzi <stefano.pigozzi@gmail.com>
Date: Fri, 13 Feb 2015 15:22:53 +0100
Subject: [PATCH] vo_opengl: fix smoothmotion coefficient calculation

Using prev_pts as the start of the scale was plain wrong. Change it to
prev_vsync.

(cherry picked from commit 3931544ef33196e1966c416cc0d60d4160cf27fb)
---
 video/out/gl_video.c | 10 +++-------
 video/out/vo.c       |  1 +
 video/out/vo.h       |  1 +
 3 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/video/out/gl_video.c b/video/out/gl_video.c
index c23e6ac436..1c70d56674 100644
--- a/video/out/gl_video.c
+++ b/video/out/gl_video.c
@@ -1749,15 +1749,11 @@ static void gl_video_interpolate_frame(struct gl_video *p,
         gl->ActiveTexture(GL_TEXTURE0 + 1);
         gl->BindTexture(p->gl_target, p->surfaces[p->surface_idx].fbotex.texture);
         gl->ActiveTexture(GL_TEXTURE0);
-        MP_DBG(p, "frame ppts: %lld, pts: %lld, vsync: %lld, DIFF: %lld\n",
-                  (long long)prev_pts, (long long)t->pts,
-                  (long long)t->next_vsync, (long long)t->next_vsync - t->pts);
         if (prev_pts < t->next_vsync && t->pts > t->next_vsync) {
-            double N = t->next_vsync - prev_pts;
-            double P = t->pts - prev_pts;
-            double prev_pts_component = N / P;
+            double N = t->next_vsync - t->prev_vsync;
+            double P = t->pts - t->prev_vsync;
             float ts = p->opts.smoothmotion_threshold;
-            inter_coeff = 1 - prev_pts_component;
+            inter_coeff = 1 - (N / P);
             inter_coeff = inter_coeff < 0.0 + ts ? 0.0 : inter_coeff;
             inter_coeff = inter_coeff > 1.0 - ts ? 1.0 : inter_coeff;
             MP_DBG(p, "inter frame ppts: %lld, pts: %lld, "
diff --git a/video/out/vo.c b/video/out/vo.c
index 10105c35aa..b85b319c3e 100644
--- a/video/out/vo.c
+++ b/video/out/vo.c
@@ -617,6 +617,7 @@ static bool render_frame(struct vo *vo)
             struct frame_timing t = (struct frame_timing) {
                 .pts        = pts,
                 .next_vsync = next_vsync,
+                .prev_vsync = prev_vsync,
             };
             vo->driver->draw_image_timed(vo, img, &t);
         } else {
diff --git a/video/out/vo.h b/video/out/vo.h
index 9be92ac482..a531744c49 100644
--- a/video/out/vo.h
+++ b/video/out/vo.h
@@ -155,6 +155,7 @@ struct vo_extra {
 struct frame_timing {
     int64_t pts;
     int64_t next_vsync;
+    int64_t prev_vsync;
 };
 
 struct vo_driver {