[Mesa-dev] [PATCH 1/3] st/mesa/i965: Allow decompressing ETC2 to GL_RGBA

Tomeu Vizoso tomeu.vizoso at collabora.com
Wed May 23 08:54:06 UTC 2018


When Mesa itself implements ETC2 decompression, it currently
decompresses to formats in the GL_BGRA component order.

That can be problematic for drivers which cannot upload the texture data
as GL_BGRA, such as Virgl when it's backed by GLES on the host.

So this commit adds a flag to _mesa_unpack_etc2_format so callers can
specify the optimal component order.

In Gallium's case, it will be requested if the format isn't in
PIPE_FORMAT_B8G8R8A8_SRGB format.

For i965, it will remain GL_BGRA, as before.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso at collabora.com>
---
 src/mesa/drivers/dri/i965/intel_mipmap_tree.c |  2 +-
 src/mesa/main/texcompress_etc.c               | 56 +++++++++++--------
 src/mesa/main/texcompress_etc.h               |  4 +-
 src/mesa/state_tracker/st_cb_texture.c        |  4 +-
 4 files changed, 41 insertions(+), 25 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/intel_mipmap_tree.c b/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
index 67086ee6c0e8..4d9019ebf4ea 100644
--- a/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
+++ b/src/mesa/drivers/dri/i965/intel_mipmap_tree.c
@@ -3370,7 +3370,7 @@ intel_miptree_unmap_etc(struct brw_context *brw,
    else
       _mesa_unpack_etc2_format(dst, mt->surf.row_pitch,
                                map->ptr, map->stride,
-                               map->w, map->h, mt->etc_format);
+                               map->w, map->h, mt->etc_format, true);
 
    intel_miptree_unmap_raw(mt);
    free(map->buffer);
diff --git a/src/mesa/main/texcompress_etc.c b/src/mesa/main/texcompress_etc.c
index 099787b7f407..ce50ba32f9d4 100644
--- a/src/mesa/main/texcompress_etc.c
+++ b/src/mesa/main/texcompress_etc.c
@@ -719,7 +719,8 @@ etc2_unpack_srgb8(uint8_t *dst_row,
                   const uint8_t *src_row,
                   unsigned src_stride,
                   unsigned width,
-                  unsigned height)
+                  unsigned height,
+                  bool bgra)
 {
    const unsigned bw = 4, bh = 4, bs = 8, comps = 4;
    struct etc2_block block;
@@ -741,11 +742,14 @@ etc2_unpack_srgb8(uint8_t *dst_row,
             for (i = 0; i < w; i++) {
                etc2_rgb8_fetch_texel(&block, i, j, dst,
                                      false /* punchthrough_alpha */);
-               /* Convert to MESA_FORMAT_B8G8R8A8_SRGB */
-               tmp = dst[0];
-               dst[0] = dst[2];
-               dst[2] = tmp;
-               dst[3] = 255;
+
+               if (bgra) {
+                  /* Convert to MESA_FORMAT_B8G8R8A8_SRGB */
+                  tmp = dst[0];
+                  dst[0] = dst[2];
+                  dst[2] = tmp;
+                  dst[3] = 255;
+               }
 
                dst += comps;
             }
@@ -801,7 +805,8 @@ etc2_unpack_srgb8_alpha8(uint8_t *dst_row,
                          const uint8_t *src_row,
                          unsigned src_stride,
                          unsigned width,
-                         unsigned height)
+                         unsigned height,
+                         bool bgra)
 {
    /* If internalformat is COMPRESSED_SRGB8_ALPHA8_ETC2_EAC, each 4 × 4 block
     * of RGBA8888 information is compressed to 128 bits. To decode a block, the
@@ -825,11 +830,13 @@ etc2_unpack_srgb8_alpha8(uint8_t *dst_row,
             for (i = 0; i < w; i++) {
                etc2_rgba8_fetch_texel(&block, i, j, dst);
 
-               /* Convert to MESA_FORMAT_B8G8R8A8_SRGB */
-               tmp = dst[0];
-               dst[0] = dst[2];
-               dst[2] = tmp;
-               dst[3] = dst[3];
+               if (bgra) {
+                  /* Convert to MESA_FORMAT_B8G8R8A8_SRGB */
+                  tmp = dst[0];
+                  dst[0] = dst[2];
+                  dst[2] = tmp;
+                  dst[3] = dst[3];
+               }
 
                dst += comps;
             }
@@ -1058,7 +1065,8 @@ etc2_unpack_srgb8_punchthrough_alpha1(uint8_t *dst_row,
                                      const uint8_t *src_row,
                                      unsigned src_stride,
                                      unsigned width,
-                                     unsigned height)
+                                     unsigned height,
+                                     bool bgra)
 {
    const unsigned bw = 4, bh = 4, bs = 8, comps = 4;
    struct etc2_block block;
@@ -1078,11 +1086,14 @@ etc2_unpack_srgb8_punchthrough_alpha1(uint8_t *dst_row,
             for (i = 0; i < w; i++) {
                etc2_rgb8_fetch_texel(&block, i, j, dst,
                                      true /* punchthrough_alpha */);
-               /* Convert to MESA_FORMAT_B8G8R8A8_SRGB */
-               tmp = dst[0];
-               dst[0] = dst[2];
-               dst[2] = tmp;
-               dst[3] = dst[3];
+
+               if (bgra) {
+                  /* Convert to MESA_FORMAT_B8G8R8A8_SRGB */
+                  tmp = dst[0];
+                  dst[0] = dst[2];
+                  dst[2] = tmp;
+                  dst[3] = dst[3];
+               }
 
                dst += comps;
             }
@@ -1206,7 +1217,8 @@ _mesa_unpack_etc2_format(uint8_t *dst_row,
                          unsigned src_stride,
                          unsigned src_width,
                          unsigned src_height,
-                         mesa_format format)
+                         mesa_format format,
+                         bool bgra)
 {
    if (format == MESA_FORMAT_ETC2_RGB8)
       etc2_unpack_rgb8(dst_row, dst_stride,
@@ -1215,7 +1227,7 @@ _mesa_unpack_etc2_format(uint8_t *dst_row,
    else if (format == MESA_FORMAT_ETC2_SRGB8)
       etc2_unpack_srgb8(dst_row, dst_stride,
                         src_row, src_stride,
-                        src_width, src_height);
+                        src_width, src_height, bgra);
    else if (format == MESA_FORMAT_ETC2_RGBA8_EAC)
       etc2_unpack_rgba8(dst_row, dst_stride,
                         src_row, src_stride,
@@ -1223,7 +1235,7 @@ _mesa_unpack_etc2_format(uint8_t *dst_row,
    else if (format == MESA_FORMAT_ETC2_SRGB8_ALPHA8_EAC)
       etc2_unpack_srgb8_alpha8(dst_row, dst_stride,
                                src_row, src_stride,
-                               src_width, src_height);
+                               src_width, src_height, bgra);
    else if (format == MESA_FORMAT_ETC2_R11_EAC)
       etc2_unpack_r11(dst_row, dst_stride,
                       src_row, src_stride,
@@ -1247,7 +1259,7 @@ _mesa_unpack_etc2_format(uint8_t *dst_row,
    else if (format == MESA_FORMAT_ETC2_SRGB8_PUNCHTHROUGH_ALPHA1)
       etc2_unpack_srgb8_punchthrough_alpha1(dst_row, dst_stride,
                                             src_row, src_stride,
-                                            src_width, src_height);
+                                            src_width, src_height, bgra);
 }
 
 
diff --git a/src/mesa/main/texcompress_etc.h b/src/mesa/main/texcompress_etc.h
index 319b7bea7154..650467ce1f32 100644
--- a/src/mesa/main/texcompress_etc.h
+++ b/src/mesa/main/texcompress_etc.h
@@ -28,6 +28,7 @@
 #include "glheader.h"
 #include "texcompress.h"
 #include "texstore.h"
+#include "pipe/p_format.h"
 
 
 GLboolean
@@ -77,7 +78,8 @@ _mesa_unpack_etc2_format(uint8_t *dst_row,
                          unsigned src_stride,
                          unsigned src_width,
                          unsigned src_height,
-                         mesa_format format);
+                         mesa_format format,
+                         bool bgra);
 
 compressed_fetch_func
 _mesa_get_etc_fetch_func(mesa_format format);
diff --git a/src/mesa/state_tracker/st_cb_texture.c b/src/mesa/state_tracker/st_cb_texture.c
index 8cc8e08a623e..7c0879084ab6 100644
--- a/src/mesa/state_tracker/st_cb_texture.c
+++ b/src/mesa/state_tracker/st_cb_texture.c
@@ -326,10 +326,12 @@ st_UnmapTextureImage(struct gl_context *ctx,
                                        transfer->box.width, transfer->box.height);
          }
          else {
+            bool bgra = stImage->pt->format == PIPE_FORMAT_B8G8R8A8_SRGB;
             _mesa_unpack_etc2_format(itransfer->map, transfer->stride,
                                      itransfer->temp_data, itransfer->temp_stride,
                                      transfer->box.width, transfer->box.height,
-                                     texImage->TexFormat);
+                                     texImage->TexFormat,
+                                     bgra);
          }
       }
 
-- 
2.17.0



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