1 files changed, 127 insertions, 1 deletions

diff --git a/src/mesa/main/texparam.c b/src/mesa/main/texparam.c
index 7285c47d173..8a5abe5e1cc 100644
--- a/src/mesa/main/texparam.c
+++ b/src/mesa/main/texparam.c
@@ -899,6 +899,25 @@ legal_get_tex_level_parameter_target(struct gl_context *ctx, GLenum target)
    case GL_PROXY_TEXTURE_2D_ARRAY_EXT:
       return (ctx->Extensions.MESA_texture_array ||
               ctx->Extensions.EXT_texture_array);
+   case GL_TEXTURE_BUFFER:
+      /* GetTexLevelParameter accepts GL_TEXTURE_BUFFER in GL 3.1+ contexts,
+       * but not in earlier versions that expose ARB_texture_buffer_object.
+       *
+       * From the ARB_texture_buffer_object spec:
+       * "(7) Do buffer textures support texture parameters (TexParameter) or
+       *      queries (GetTexParameter, GetTexLevelParameter, GetTexImage)?
+       *
+       *    RESOLVED:  No. [...] Note that the spec edits above don't add
+       *    explicit error language for any of these cases.  That is because
+       *    each of the functions enumerate the set of valid <target>
+       *    parameters.  Not editing the spec to allow TEXTURE_BUFFER_ARB in
+       *    these cases means that target is not legal, and an INVALID_ENUM
+       *    error should be generated."
+       *
+       * From the OpenGL 3.1 spec:
+       * "target may also be TEXTURE_BUFFER, indicating the texture buffer."
+       */
+      return _mesa_is_desktop_gl(ctx) && ctx->Version >= 31;
    default:
       return GL_FALSE;
    }
@@ -1052,6 +1071,110 @@ invalid_pname:
 }
 
 
+static void
+get_tex_level_parameter_buffer(struct gl_context *ctx,
+                               struct gl_texture_object *texObj,
+                               GLenum target, GLint level,
+                               GLenum pname, GLint *params)
+{
+   struct gl_buffer_object *bo = texObj->BufferObject;
+   gl_format texFormat = texObj->_BufferObjectFormat;
+   GLenum internalFormat = texObj->BufferObjectFormat;
+   GLenum baseFormat = _mesa_get_format_base_format(texFormat);
+
+   if (!bo) {
+      /* undefined texture buffer object */
+      *params = pname == GL_TEXTURE_COMPONENTS ? 1 : 0;
+      return;
+   }
+
+   switch (pname) {
+      case GL_TEXTURE_BUFFER_DATA_STORE_BINDING:
+         *params = bo->Name;
+         break;
+      case GL_TEXTURE_WIDTH:
+         *params = bo->Size;
+         break;
+      case GL_TEXTURE_HEIGHT:
+      case GL_TEXTURE_DEPTH:
+      case GL_TEXTURE_BORDER:
+      case GL_TEXTURE_SHARED_SIZE:
+      case GL_TEXTURE_COMPRESSED:
+         *params = 0;
+         break;
+      case GL_TEXTURE_INTERNAL_FORMAT:
+         *params = internalFormat;
+         break;
+      case GL_TEXTURE_RED_SIZE:
+      case GL_TEXTURE_GREEN_SIZE:
+      case GL_TEXTURE_BLUE_SIZE:
+      case GL_TEXTURE_ALPHA_SIZE:
+         if (_mesa_base_format_has_channel(baseFormat, pname))
+            *params = _mesa_get_format_bits(texFormat, pname);
+         else
+            *params = 0;
+         break;
+      case GL_TEXTURE_INTENSITY_SIZE:
+      case GL_TEXTURE_LUMINANCE_SIZE:
+         if (_mesa_base_format_has_channel(baseFormat, pname)) {
+            *params = _mesa_get_format_bits(texFormat, pname);
+            if (*params == 0) {
+               /* intensity or luminance is probably stored as RGB[A] */
+               *params = MIN2(_mesa_get_format_bits(texFormat,
+                                                    GL_TEXTURE_RED_SIZE),
+                              _mesa_get_format_bits(texFormat,
+                                                    GL_TEXTURE_GREEN_SIZE));
+            }
+         } else {
+            *params = 0;
+         }
+         break;
+      case GL_TEXTURE_DEPTH_SIZE_ARB:
+      case GL_TEXTURE_STENCIL_SIZE_EXT:
+         *params = _mesa_get_format_bits(texFormat, pname);
+         break;
+
+      /* GL_ARB_texture_compression */
+      case GL_TEXTURE_COMPRESSED_IMAGE_SIZE:
+         if (_mesa_is_format_compressed(texFormat) &&
+             !_mesa_is_proxy_texture(target)) {
+            *params = _mesa_format_image_size(texFormat, bo->Size, 0, 0);
+         } else {
+            _mesa_error(ctx, GL_INVALID_OPERATION,
+                        "glGetTexLevelParameter[if]v(pname)");
+         }
+         break;
+
+      /* GL_ARB_texture_float */
+      case GL_TEXTURE_RED_TYPE_ARB:
+      case GL_TEXTURE_GREEN_TYPE_ARB:
+      case GL_TEXTURE_BLUE_TYPE_ARB:
+      case GL_TEXTURE_ALPHA_TYPE_ARB:
+      case GL_TEXTURE_LUMINANCE_TYPE_ARB:
+      case GL_TEXTURE_INTENSITY_TYPE_ARB:
+      case GL_TEXTURE_DEPTH_TYPE_ARB:
+         if (!ctx->Extensions.ARB_texture_float)
+            goto invalid_pname;
+         if (_mesa_base_format_has_channel(baseFormat, pname))
+            *params = _mesa_get_format_datatype(texFormat);
+         else
+            *params = GL_NONE;
+         break;
+
+      default:
+         goto invalid_pname;
+   }
+
+   /* no error if we get here */
+   return;
+
+invalid_pname:
+   _mesa_error(ctx, GL_INVALID_ENUM,
+               "glGetTexLevelParameter[if]v(pname=%s)",
+               _mesa_lookup_enum_by_nr(pname));
+}
+
+
 void GLAPIENTRY
 _mesa_GetTexLevelParameterfv( GLenum target, GLint level,
                               GLenum pname, GLfloat *params )
@@ -1096,7 +1219,10 @@ _mesa_GetTexLevelParameteriv( GLenum target, GLint level,
 
    texObj = _mesa_select_tex_object(ctx, texUnit, target);
 
-   get_tex_level_parameter_image(ctx, texObj, target, level, pname, params);
+   if (target == GL_TEXTURE_BUFFER)
+      get_tex_level_parameter_buffer(ctx, texObj, target, level, pname, params);
+   else
+      get_tex_level_parameter_image(ctx, texObj, target, level, pname, params);
 }