Mesa (master): mesa: add missing texel fetch code for sRGB DXT formats

[Brian Paul]

Module: Mesa
Branch: master
Commit: 7c35521295e647978ed8e7ab9f490ef70d672cd3
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=7c35521295e647978ed8e7ab9f490ef70d672cd3

Author: Brian Paul <brianp at vmware.com>
Date:   Fri Dec 21 13:41:23 2012 -0700

mesa: add missing texel fetch code for sRGB DXT formats

Fixes http://bugs.freedesktop.org/show_bug.cgi?id=58548

---

 src/mesa/main/texcompress.c      |    4 ++
 src/mesa/main/texcompress_s3tc.c |   82 ++++++++++++++++++++++++++++++++++++++
 2 files changed, 86 insertions(+), 0 deletions(-)

diff --git a/src/mesa/main/texcompress.c b/src/mesa/main/texcompress.c
index 33c580a..077a967 100644
--- a/src/mesa/main/texcompress.c
+++ b/src/mesa/main/texcompress.c
@@ -533,6 +533,10 @@ _mesa_get_compressed_fetch_func(gl_format format)
    case MESA_FORMAT_RGBA_DXT1:
    case MESA_FORMAT_RGBA_DXT3:
    case MESA_FORMAT_RGBA_DXT5:
+   case MESA_FORMAT_SRGB_DXT1:
+   case MESA_FORMAT_SRGBA_DXT1:
+   case MESA_FORMAT_SRGBA_DXT3:
+   case MESA_FORMAT_SRGBA_DXT5:
       return _mesa_get_dxt_fetch_func(format);
    case MESA_FORMAT_RGB_FXT1:
    case MESA_FORMAT_RGBA_FXT1:
diff --git a/src/mesa/main/texcompress_s3tc.c b/src/mesa/main/texcompress_s3tc.c
index 23a5a08..4a81ad8 100644
--- a/src/mesa/main/texcompress_s3tc.c
+++ b/src/mesa/main/texcompress_s3tc.c
@@ -417,6 +417,80 @@ fetch_rgba_dxt5(const GLubyte *map, const GLuint imageOffsets[],
 }
 
 
+static void
+fetch_srgb_dxt1(const GLubyte *map, const GLuint imageOffsets[],
+                GLint rowStride, GLint i, GLint j, GLint k, GLfloat *texel)
+{
+   if (fetch_ext_rgb_dxt1) {
+      GLuint sliceOffset = k ? imageOffsets[k] / 2 : 0;
+      GLubyte tex[4];
+      fetch_ext_rgb_dxt1(rowStride, map + sliceOffset, i, j, tex);
+      texel[RCOMP] = _mesa_nonlinear_to_linear(tex[RCOMP]);
+      texel[GCOMP] = _mesa_nonlinear_to_linear(tex[GCOMP]);
+      texel[BCOMP] = _mesa_nonlinear_to_linear(tex[BCOMP]);
+      texel[ACOMP] = UBYTE_TO_FLOAT(tex[ACOMP]);
+   }
+   else {
+      problem("srgb_dxt1");
+   }
+}
+
+static void
+fetch_srgba_dxt1(const GLubyte *map, const GLuint imageOffsets[],
+                 GLint rowStride, GLint i, GLint j, GLint k, GLfloat *texel)
+{
+   if (fetch_ext_rgba_dxt1) {
+      GLuint sliceOffset = k ? imageOffsets[k] / 2 : 0;
+      GLubyte tex[4];
+      fetch_ext_rgba_dxt1(rowStride, map + sliceOffset, i, j, tex);
+      texel[RCOMP] = _mesa_nonlinear_to_linear(tex[RCOMP]);
+      texel[GCOMP] = _mesa_nonlinear_to_linear(tex[GCOMP]);
+      texel[BCOMP] = _mesa_nonlinear_to_linear(tex[BCOMP]);
+      texel[ACOMP] = UBYTE_TO_FLOAT(tex[ACOMP]);
+   }
+   else {
+      problem("srgba_dxt1");
+   }
+}
+
+static void
+fetch_srgba_dxt3(const GLubyte *map, const GLuint imageOffsets[],
+                 GLint rowStride, GLint i, GLint j, GLint k, GLfloat *texel)
+{
+   if (fetch_ext_rgba_dxt3) {
+      GLuint sliceOffset = k ? imageOffsets[k] : 0;
+      GLubyte tex[4];
+      fetch_ext_rgba_dxt3(rowStride, map + sliceOffset, i, j, tex);
+      texel[RCOMP] = _mesa_nonlinear_to_linear(tex[RCOMP]);
+      texel[GCOMP] = _mesa_nonlinear_to_linear(tex[GCOMP]);
+      texel[BCOMP] = _mesa_nonlinear_to_linear(tex[BCOMP]);
+      texel[ACOMP] = UBYTE_TO_FLOAT(tex[ACOMP]);
+   }
+   else {
+      problem("srgba_dxt3");
+   }
+}
+
+static void
+fetch_srgba_dxt5(const GLubyte *map, const GLuint imageOffsets[],
+                 GLint rowStride, GLint i, GLint j, GLint k, GLfloat *texel)
+{
+   if (fetch_ext_rgba_dxt5) {
+      GLuint sliceOffset = k ? imageOffsets[k] : 0;
+      GLubyte tex[4];
+      fetch_ext_rgba_dxt5(rowStride, map + sliceOffset, i, j, tex);
+      texel[RCOMP] = _mesa_nonlinear_to_linear(tex[RCOMP]);
+      texel[GCOMP] = _mesa_nonlinear_to_linear(tex[GCOMP]);
+      texel[BCOMP] = _mesa_nonlinear_to_linear(tex[BCOMP]);
+      texel[ACOMP] = UBYTE_TO_FLOAT(tex[ACOMP]);
+   }
+   else {
+      problem("srgba_dxt5");
+   }
+}
+
+
+
 compressed_fetch_func
 _mesa_get_dxt_fetch_func(gl_format format)
 {
@@ -429,6 +503,14 @@ _mesa_get_dxt_fetch_func(gl_format format)
       return fetch_rgba_dxt3;
    case MESA_FORMAT_RGBA_DXT5:
       return fetch_rgba_dxt5;
+   case MESA_FORMAT_SRGB_DXT1:
+      return fetch_srgb_dxt1;
+   case MESA_FORMAT_SRGBA_DXT1:
+      return fetch_srgba_dxt1;
+   case MESA_FORMAT_SRGBA_DXT3:
+      return fetch_srgba_dxt3;
+   case MESA_FORMAT_SRGBA_DXT5:
+      return fetch_srgba_dxt5;
    default:
       return NULL;
    }