[Mesa-dev] [PATCH v2 2/3] nir: Add a lowering pass for UYVY textures

[Lin, Johnson]

Kristian,

Thanks for the review comments. By my tests, UYVY buffer can be sampled and rendered correctly. So there is no swap of U/V channel here. 

-----Original Message-----
From: Lin, Johnson 
Sent: Tuesday, June 20, 2017 9:43 AM
To: mesa-dev at lists.freedesktop.org
Cc: Lin, Johnson <johnson.lin at intel.com>
Subject: [PATCH v2 2/3] nir: Add a lowering pass for UYVY textures

Similar with support for YUYV but with byte order difference in sampler
---
 src/compiler/nir/nir.h           |  1 +
 src/compiler/nir/nir_lower_tex.c | 16 ++++++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h index ab7ba14303b7..1b4e47058d4d 100644
--- a/src/compiler/nir/nir.h
+++ b/src/compiler/nir/nir.h
@@ -2449,6 +2449,7 @@ typedef struct nir_lower_tex_options {
    unsigned lower_y_uv_external;
    unsigned lower_y_u_v_external;
    unsigned lower_yx_xuxv_external;
+   unsigned lower_xy_uxvx_external;
 
    /**
     * To emulate certain texture wrap modes, this can be used diff --git a/src/compiler/nir/nir_lower_tex.c b/src/compiler/nir/nir_lower_tex.c
index 4ef81955513e..5593f9890b28 100644
--- a/src/compiler/nir/nir_lower_tex.c
+++ b/src/compiler/nir/nir_lower_tex.c
@@ -301,6 +301,18 @@ lower_yx_xuxv_external(nir_builder *b, nir_tex_instr *tex)
                       nir_channel(b, xuxv, 3));  }
 
+static void lower_xy_uxvx_external(nir_builder *b, nir_tex_instr *tex) 
+{
+  b->cursor = nir_after_instr(&tex->instr);
+
+  nir_ssa_def *y = sample_plane(b, tex, 0);  nir_ssa_def *uxvx = 
+ sample_plane(b, tex, 1);
+
+  convert_yuv_to_rgb(b, tex,
+                     nir_channel(b, y, 1),
+                     nir_channel(b, uxvx, 2),
+                     nir_channel(b, uxvx, 0)); }
+
 /*
  * Emits a textureLod operation used to replace an existing
  * textureGrad instruction.
@@ -760,6 +772,10 @@ nir_lower_tex_block(nir_block *block, nir_builder *b,
          progress = true;
       }
 
+      if ((1 << tex->texture_index) & options->lower_xy_uxvx_external) {
+         lower_xy_uxvx_external(b, tex);
+         progress = true;
+      }
 
       if (sat_mask) {
          saturate_src(b, tex, sat_mask);
--
1.9.1