mesa: Add RGTC texture store/fetch support.

This adds support for the RGTC unsigned and signed
texture storage and fetch methods.

the code is a port of the DXT5 alpha compression code.

Signed-off-by: Dave Airlie <airlied@redhat.com>

src/mesa/main/formats.c

@@ -890,7 +890,43 @@ static struct gl_format_info format_info[MESA_FORMAT_COUNT] =
       16, 16, 16, 16,
       0, 0, 0, 0, 0,
       1, 1, 8
-   }
+   },
+   {
+     MESA_FORMAT_RED_RGTC1,
+     "MESA_FORMAT_RED_RGTC1",
+     GL_RED,
+     GL_UNSIGNED_NORMALIZED,
+     4, 0, 0, 0,
+     0, 0, 0, 0, 0,
+     4, 4, 8                     /* 8 bytes per 4x4 block */
+   },
+   {
+     MESA_FORMAT_SIGNED_RED_RGTC1,
+     "MESA_FORMAT_SIGNED_RED_RGTC1",
+     GL_RED,
+     GL_SIGNED_NORMALIZED,
+     4, 0, 0, 0,
+     0, 0, 0, 0, 0,
+     4, 4, 8                     /* 8 bytes per 4x4 block */
+   },
+   {
+     MESA_FORMAT_RG_RGTC2,
+     "MESA_FORMAT_RG_RGTC2",
+     GL_RG,
+     GL_UNSIGNED_NORMALIZED,
+     4, 4, 0, 0,
+     0, 0, 0, 0, 0,
+     4, 4, 16                     /* 16 bytes per 4x4 block */
+   },
+   {
+     MESA_FORMAT_SIGNED_RG_RGTC2,
+     "MESA_FORMAT_SIGNED_RG_RGTC2",
+     GL_RG,
+     GL_SIGNED_NORMALIZED,
+     4, 4, 0, 0,
+     0, 0, 0, 0, 0,
+     4, 4, 16                     /* 16 bytes per 4x4 block */
+   },
 };
 
 
@@ -1530,6 +1566,10 @@ _mesa_format_to_type_and_comps(gl_format format,
    case MESA_FORMAT_SRGBA_DXT5:
 #endif
 #endif
+   case MESA_FORMAT_RED_RGTC1:
+   case MESA_FORMAT_SIGNED_RED_RGTC1:
+   case MESA_FORMAT_RG_RGTC2:
+   case MESA_FORMAT_SIGNED_RG_RGTC2:
       /* XXX generate error instead? */
       *datatype = GL_UNSIGNED_BYTE;
       *comps = 0;

src/mesa/main/formats.h

@@ -179,6 +179,12 @@ typedef enum
    MESA_FORMAT_RGBA_16,           /* ... */
    /*@}*/
 
+   /*@{*/
+   MESA_FORMAT_RED_RGTC1,
+   MESA_FORMAT_SIGNED_RED_RGTC1,
+   MESA_FORMAT_RG_RGTC2,
+   MESA_FORMAT_SIGNED_RG_RGTC2,
+   /*@}*/
    MESA_FORMAT_COUNT
 } gl_format;
 

src/mesa/main/texcompress.c

@@ -64,6 +64,7 @@ _mesa_get_compressed_formats(struct gl_context *ctx, GLint *formats, GLboolean a
          n += 2;
       }
    }
+   /* don't return RGTC - ARB_texture_compression_rgtc query 19 */
    if (ctx->Extensions.EXT_texture_compression_s3tc) {
       if (formats) {
          formats[n++] = GL_COMPRESSED_RGB_S3TC_DXT1_EXT;
@@ -163,6 +164,15 @@ _mesa_glenum_to_compressed_format(GLenum format)
    case GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT:
       return MESA_FORMAT_SRGBA_DXT5;
 
+   case GL_COMPRESSED_RED_RGTC1:
+      return MESA_FORMAT_RED_RGTC1;
+   case GL_COMPRESSED_SIGNED_RED_RGTC1:
+      return MESA_FORMAT_SIGNED_RED_RGTC1;
+   case GL_COMPRESSED_RG_RGTC2:
+      return MESA_FORMAT_RG_RGTC2;
+   case GL_COMPRESSED_SIGNED_RG_RGTC2:
+      return MESA_FORMAT_SIGNED_RG_RGTC2;
+
    default:
       return MESA_FORMAT_NONE;
    }
@@ -209,6 +219,16 @@ _mesa_compressed_format_to_glenum(struct gl_context *ctx, GLuint mesaFormat)
       return GL_COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT;
 #endif
 #endif
+
+   case MESA_FORMAT_RED_RGTC1:
+      return GL_COMPRESSED_RED_RGTC1;
+   case MESA_FORMAT_SIGNED_RED_RGTC1:
+      return GL_COMPRESSED_SIGNED_RED_RGTC1;
+   case MESA_FORMAT_RG_RGTC2:
+      return GL_COMPRESSED_RG_RGTC2;
+   case MESA_FORMAT_SIGNED_RG_RGTC2:
+      return GL_COMPRESSED_SIGNED_RG_RGTC2;
+
    default:
       _mesa_problem(ctx, "Unexpected mesa texture format in"
                     " _mesa_compressed_format_to_glenum()");

src/mesa/main/texcompress_rgtc.h

@@ -0,0 +1,60 @@
+/*
+ * Copyright (C) 2011 Red Hat Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+#ifndef TEXCOMPRESS_RGTC_H
+#define TEXCOMPRESS_RGTC_H
+
+#include "glheader.h"
+#include "mfeatures.h"
+#include "texstore.h"
+
+struct gl_texture_image;
+
+extern GLboolean
+_mesa_texstore_red_rgtc1(TEXSTORE_PARAMS);
+
+extern GLboolean
+_mesa_texstore_signed_red_rgtc1(TEXSTORE_PARAMS);
+
+extern GLboolean
+_mesa_texstore_rg_rgtc2(TEXSTORE_PARAMS);
+
+extern GLboolean
+_mesa_texstore_signed_rg_rgtc2(TEXSTORE_PARAMS);
+
+extern void
+_mesa_fetch_texel_2d_f_red_rgtc1(const struct gl_texture_image *texImage,
+				 GLint i, GLint j, GLint k, GLfloat *texel);
+
+extern void
+_mesa_fetch_texel_2d_f_signed_red_rgtc1(const struct gl_texture_image *texImage,
+					GLint i, GLint j, GLint k, GLfloat *texel);
+
+extern void
+_mesa_fetch_texel_2d_f_rg_rgtc2(const struct gl_texture_image *texImage,
+				 GLint i, GLint j, GLint k, GLfloat *texel);
+
+extern void
+_mesa_fetch_texel_2d_f_signed_rg_rgtc2(const struct gl_texture_image *texImage,
+				       GLint i, GLint j, GLint k, GLfloat *texel);
+#endif

src/mesa/main/texfetch.c

@@ -38,6 +38,7 @@
 #include "texcompress.h"
 #include "texcompress_fxt1.h"
 #include "texcompress_s3tc.h"
+#include "texcompress_rgtc.h"
 #include "texfetch.h"
 #include "teximage.h"
 
@@ -756,7 +757,35 @@ texfetch_funcs[MESA_FORMAT_COUNT] =
       fetch_texel_2d_rgba_16,
       fetch_texel_3d_rgba_16,
       store_texel_rgba_16
-   }
+   },
+   {
+      MESA_FORMAT_RED_RGTC1,
+      NULL,
+      _mesa_fetch_texel_2d_f_red_rgtc1,
+      NULL,
+      NULL
+   },
+   {
+      MESA_FORMAT_SIGNED_RED_RGTC1,
+      NULL,
+      _mesa_fetch_texel_2d_f_signed_red_rgtc1,
+      NULL,
+      NULL
+   },
+   {
+      MESA_FORMAT_RG_RGTC2,
+      NULL,
+      _mesa_fetch_texel_2d_f_rg_rgtc2,
+      NULL,
+      NULL
+   },
+   {
+      MESA_FORMAT_SIGNED_RG_RGTC2,
+      NULL,
+      _mesa_fetch_texel_2d_f_signed_rg_rgtc2,
+      NULL,
+      NULL
+   },
 };
 
 

src/mesa/main/texstore.c

@@ -65,6 +65,7 @@
 #include "pack.h"
 #include "texcompress.h"
 #include "texcompress_fxt1.h"
+#include "texcompress_rgtc.h"
 #include "texcompress_s3tc.h"
 #include "teximage.h"
 #include "texstore.h"
@@ -4128,7 +4129,12 @@ texstore_funcs[MESA_FORMAT_COUNT] =
    { MESA_FORMAT_SIGNED_RG_16, _mesa_texstore_signed_rgba_16 },
    { MESA_FORMAT_SIGNED_RGB_16, _mesa_texstore_signed_rgba_16 },
    { MESA_FORMAT_SIGNED_RGBA_16, _mesa_texstore_signed_rgba_16 },
-   { MESA_FORMAT_RGBA_16, _mesa_texstore_rgba_16 }
+   { MESA_FORMAT_RGBA_16, _mesa_texstore_rgba_16 },
+
+   { MESA_FORMAT_RED_RGTC1, _mesa_texstore_red_rgtc1 },
+   { MESA_FORMAT_SIGNED_RED_RGTC1, _mesa_texstore_signed_red_rgtc1 },
+   { MESA_FORMAT_RG_RGTC2, _mesa_texstore_rg_rgtc2 },
+   { MESA_FORMAT_SIGNED_RG_RGTC2, _mesa_texstore_signed_rg_rgtc2 }
 };
 
 

src/mesa/sources.mak

@@ -78,6 +78,7 @@ MAIN_SOURCES = \
 	main/stencil.c \
 	main/syncobj.c \
 	main/texcompress.c \
+	main/texcompress_rgtc.c \
 	main/texcompress_s3tc.c \
 	main/texcompress_fxt1.c \
 	main/texenv.c \