mesa: Add decoding functions for GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2

Data in GL_COMPRESSED_SRGB8_PUNCHTHROUGH_ALPHA1_ETC2 format is decoded and stored
in MESA_FORMAT_SARGB.

Signed-off-by: Anuj Phogat <anuj.phogat@gmail.com>
Reviewed-by: Brian Paul <brianp@vmware.com>

5 files changed, 90 insertions, 4 deletions

diff --git a/src/mesa/main/texcompress.c b/src/mesa/main/texcompress.c
index c05b89124d2..372a483faaa 100644
--- a/src/mesa/main/texcompress.c
+++ b/src/mesa/main/texcompress.c
@@ -637,3 +637,3 @@ _mesa_decompress_image(gl_format format, GLuint width, GLuint height,
    case MESA_FORMAT_ETC2_SRGB8_PUNCHTHROUGH_ALPHA1:
-      /* fetch = _mesa_fetch_texel_2d_f_etc2_srgb8_punchthrough_alpha1; -- not implemented yet */
+      fetch = _mesa_fetch_texel_2d_f_etc2_srgb8_punchthrough_alpha1;
       break;
diff --git a/src/mesa/main/texcompress_etc.c b/src/mesa/main/texcompress_etc.c
index 7c8287bfba7..b98ff029a2e 100644
--- a/src/mesa/main/texcompress_etc.c
+++ b/src/mesa/main/texcompress_etc.c
@@ -36,2 +36,3 @@
  * MESA_FORMAT_ETC2_RGB8_PUNCHTHROUGH_ALPHA1
+ * MESA_FORMAT_ETC2_SRGB8_PUNCHTHROUGH_ALPHA1
  */
@@ -1043,2 +1044,43 @@ etc2_unpack_rgb8_punchthrough_alpha1(uint8_t *dst_row,
 
+static void
+etc2_unpack_srgb8_punchthrough_alpha1(uint8_t *dst_row,
+                                     unsigned dst_stride,
+                                     const uint8_t *src_row,
+                                     unsigned src_stride,
+                                     unsigned width,
+                                     unsigned height)
+{
+   const unsigned bw = 4, bh = 4, bs = 8, comps = 4;
+   struct etc2_block block;
+   unsigned x, y, i, j;
+   uint8_t tmp;
+
+   for (y = 0; y < height; y += bh) {
+      const uint8_t *src = src_row;
+
+      for (x = 0; x < width; x+= bw) {
+         etc2_rgb8_parse_block(&block, src,
+                               true /* punchthrough_alpha */);
+         for (j = 0; j < bh; j++) {
+            uint8_t *dst = dst_row + (y + j) * dst_stride + x * comps;
+            for (i = 0; i < bw; i++) {
+               etc2_rgb8_fetch_texel(&block, i, j, dst,
+                                     true /* punchthrough_alpha */);
+               /* Convert to MESA_FORMAT_SARGB8 */
+               tmp = dst[0];
+               dst[0] = dst[2];
+               dst[2] = tmp;
+               dst[3] = dst[3];
+
+               dst += comps;
+            }
+         }
+
+         src += bs;
+      }
+
+      src_row += src_stride;
+   }
+}
+
 /* ETC2 texture formats are valid in glCompressedTexImage2D and
@@ -1117,2 +1159,10 @@ _mesa_texstore_etc2_rgb8_punchthrough_alpha1(TEXSTORE_PARAMS)
 
+GLboolean
+_mesa_texstore_etc2_srgb8_punchthrough_alpha1(TEXSTORE_PARAMS)
+{
+   ASSERT(0);
+
+   return GL_FALSE;
+}
+
 void
@@ -1318,2 +1368,25 @@ _mesa_fetch_texel_2d_f_etc2_rgb8_punchthrough_alpha1(
 
+void
+_mesa_fetch_texel_2d_f_etc2_srgb8_punchthrough_alpha1(
+   const struct swrast_texture_image *texImage,
+   GLint i, GLint j,
+   GLint k, GLfloat *texel)
+{
+   struct etc2_block block;
+   uint8_t dst[4];
+   const uint8_t *src;
+
+   src = texImage->Map +
+      (((texImage->RowStride + 3) / 4) * (j / 4) + (i / 4)) * 8;
+
+   etc2_rgb8_parse_block(&block, src,
+                         true /* punchthrough alpha */);
+   etc2_rgb8_fetch_texel(&block, i % 4, j % 4, dst,
+                         true /* punchthrough alpha */);
+   texel[RCOMP] = _mesa_nonlinear_to_linear(dst[0]);
+   texel[GCOMP] = _mesa_nonlinear_to_linear(dst[1]);
+   texel[BCOMP] = _mesa_nonlinear_to_linear(dst[2]);
+   texel[ACOMP] = UBYTE_TO_FLOAT(dst[3]);
+}
+
 /**
@@ -1329,2 +1402,3 @@ _mesa_fetch_texel_2d_f_etc2_rgb8_punchthrough_alpha1(
  * `MESA_FORMAT_ETC2_RGB8_PUNCHTHROUGH_ALPHA1`
+ * `MESA_FORMAT_ETC2_SRGB8_PUNCHTHROUGH_ALPHA1`
  *
@@ -1383,2 +1457,6 @@ _mesa_unpack_etc2_format(uint8_t *dst_row,
                                            src_width, src_height);
+   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);
 }
diff --git a/src/mesa/main/texcompress_etc.h b/src/mesa/main/texcompress_etc.h
index 05934794609..5e086d4e79c 100644
--- a/src/mesa/main/texcompress_etc.h
+++ b/src/mesa/main/texcompress_etc.h
@@ -63,2 +63,5 @@ _mesa_texstore_etc2_rgb8_punchthrough_alpha1(TEXSTORE_PARAMS);
 
+GLboolean
+_mesa_texstore_etc2_srgb8_punchthrough_alpha1(TEXSTORE_PARAMS);
+
 void
@@ -103,2 +106,7 @@ _mesa_fetch_texel_2d_f_etc2_rgb8_punchthrough_alpha1(
 void
+_mesa_fetch_texel_2d_f_etc2_srgb8_punchthrough_alpha1(
+                                 const struct swrast_texture_image *texImage,
+                                 GLint i, GLint j,
+                                 GLint k, GLfloat *texel);
+void
 _mesa_etc1_unpack_rgba8888(uint8_t *dst_row,
diff --git a/src/mesa/main/texstore.c b/src/mesa/main/texstore.c
index 80edd0008e7..26c5b670312 100644
--- a/src/mesa/main/texstore.c
+++ b/src/mesa/main/texstore.c
@@ -4136,4 +4136,4 @@ _mesa_get_texstore_func(gl_format format)
          _mesa_texstore_etc2_rgb8_punchthrough_alpha1;
-      /* table[MESA_FORMAT_ETC2_SRGB8_PUNCHTHROUGH_ALPHA1] =
-         _mesa_texstore_etc2_srgb8_punchthrough_alpha1; -- not implemented yet */
+      table[MESA_FORMAT_ETC2_SRGB8_PUNCHTHROUGH_ALPHA1] =
+         _mesa_texstore_etc2_srgb8_punchthrough_alpha1;
       table[MESA_FORMAT_SIGNED_A8] = _mesa_texstore_snorm8;
diff --git a/src/mesa/swrast/s_texfetch.c b/src/mesa/swrast/s_texfetch.c
index 579dd5c5fc1..86b01a0b346 100644
--- a/src/mesa/swrast/s_texfetch.c
+++ b/src/mesa/swrast/s_texfetch.c
@@ -1087,3 +1087,3 @@ texfetch_funcs[] =
       NULL,
-      NULL /* _mesa_fetch_texel_2d_f_etc2_srgb8_punchthrough_alpha1 -- not implemented yet */,
+      _mesa_fetch_texel_2d_f_etc2_srgb8_punchthrough_alpha1,
       NULL