vo_gpu: fix broken chroma plane for rotated semi-planar formats

For image formats with 2 or more chroma planes such as YU12, there is
a plane merging pass for these planes calling finish_pass_tex which
does a format conversion. After this conversion, the cscale shader
afterwards works properly.

However, for image formats with only 1 chroma plane (semi-planar formats),
including NV12 and P010, this merging pass is never called, which breaks
the cscale shader afterwards if the video is rotated with subsampled
chroma.

Fix this by adding an explicit conversion pass if this situation is
detected after the pre-scale hooks, so if there are shaders hooking on
CHROMA (like the deband filter) and the conversion is done by pass_hook
already, this conversion won't be called.

1 files changed, 19 insertions, 0 deletions

diff --git a/video/out/gpu/video.c b/video/out/gpu/video.c
index fe6ec1cdde..3764e5d712 100644
--- a/video/out/gpu/video.c
+++ b/video/out/gpu/video.c
@@ -212,6 +212,7 @@ struct gl_video {
     struct ra_tex *merge_tex[4];
     struct ra_tex *scale_tex[4];
     struct ra_tex *integer_tex[4];
+    struct ra_tex *chroma_tex[4];
     struct ra_tex *indirect_tex;
     struct ra_tex *blend_subs_tex;
     struct ra_tex *error_diffusion_tex[2];
@@ -573,6 +574,7 @@ static void uninit_rendering(struct gl_video *p)
         ra_tex_free(p->ra, &p->merge_tex[n]);
         ra_tex_free(p->ra, &p->scale_tex[n]);
         ra_tex_free(p->ra, &p->integer_tex[n]);
+        ra_tex_free(p->ra, &p->chroma_tex[n]);
     }
 
     ra_tex_free(p->ra, &p->indirect_tex);
@@ -2199,6 +2201,23 @@ static void pass_read_video(struct gl_video *p)
         }
     }
 
+    // If chroma textures are in a subsampled semi-planar format and rotated,
+    // introduce an explicit conversion pass to avoid breaking chroma scalers.
+    for (int n = 0; n < 4; n++) {
+        if (img[n].tex && img[n].type == PLANE_CHROMA &&
+            img[n].tex->params.format->num_components == 2 &&
+            p->image_params.rotate % 180 == 90 &&
+            p->ra_format.chroma_w != 1)
+        {
+            GLSLF("// chroma fix for rotated plane %d\n", n);
+            copy_image(p, &(int){0}, img[n]);
+            pass_describe(p, "chroma fix for rotated plane");
+            finish_pass_tex(p, &p->chroma_tex[n], img[n].w, img[n].h);
+            img[n] = image_wrap(p->chroma_tex[n], img[n].type,
+                                img[n].components);
+        }
+    }
+
     // At this point all planes are finalized but they may not be at the
     // required size yet. Furthermore, they may have texture offsets that
     // require realignment.