Anton Baskanov : wined3d: Fix the odd line condition in gen_yv12_read().

[Alexandre Julliard]

Module: wine
Branch: master
Commit: f4d2bdddcac7ca4a13b857ebc1e92ae45cb481c4
URL:    https://source.winehq.org/git/wine.git/?a=commit;h=f4d2bdddcac7ca4a13b857ebc...

Author: Anton Baskanov <baskanov(a)gmail.com>
Date:   Tue Aug 31 23:26:24 2021 +0700

wined3d: Fix the odd line condition in gen_yv12_read().

Signed-off-by: Anton Baskanov <baskanov(a)gmail.com>
Signed-off-by: Henri Verbeet <hverbeet(a)codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard(a)winehq.org>

---

 dlls/wined3d/glsl_shader.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/dlls/wined3d/glsl_shader.c b/dlls/wined3d/glsl_shader.c
index 5ae90148dc8..c760d519b30 100644
--- a/dlls/wined3d/glsl_shader.c
+++ b/dlls/wined3d/glsl_shader.c
@@ -12621,8 +12621,10 @@ static void gen_yv12_read(struct wined3d_string_buffer *buffer,
      * Don't forget to clamp the y values in into the range, otherwise we'll
      * get filtering bleeding. */
 
-    /* Read odd lines from the right side (add 0.5 to the x coordinate). */
-    shader_addline(buffer, "    if (fract(floor(texcoord.y * size.y) * 0.5 + 1.0 / 6.0) >= 0.5)\n");
+    /* Read odd lines from the right side (add 0.5 to the x coordinate). Keep
+     * in mind that each line of the chroma plane corresponds to 2 lines of the
+     * resulting image. */
+    shader_addline(buffer, "    if (fract(floor(texcoord.y * size.y) * 0.25 + 1.0 / 6.0) >= 0.5)\n");
     shader_addline(buffer, "        texcoord.x += 0.5;\n");
 
     /* Clamp, keep the half pixel origin in mind. */