mesa: add MaxNumLevels to gl_texture_image, remove MaxLog2

MaxLog2 led to bugs, because it didn't work well with 1D and 3D textures.

NOTE: This is a candidate for the stable branches.

v2: correct the comment at MaxNumlevels

Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
(cherry picked from commit 8111342e81)

Conflicts:
	src/mesa/main/teximage.h

src/mesa/drivers/dri/nouveau/nouveau_texture.c

@@ -369,7 +369,7 @@ get_last_level(struct gl_texture_object *t)
 	    t->Sampler.MinFilter == GL_LINEAR || !base)
 		return t->BaseLevel;
 	else
-		return MIN2(t->BaseLevel + base->MaxLog2, t->MaxLevel);
+		return MIN2(t->BaseLevel + base->MaxNumLevels - 1, t->MaxLevel);
 }
 
 static void

src/mesa/drivers/dri/radeon/radeon_mipmap_tree.c

@@ -270,7 +270,7 @@ static void calculate_min_max_lod(struct gl_sampler_object *samp, struct gl_text
 			minLod = MIN2(minLod, tObj->MaxLevel);
 			maxLod = tObj->BaseLevel + (GLint)(samp->MaxLod + 0.5);
 			maxLod = MIN2(maxLod, tObj->MaxLevel);
-			maxLod = MIN2(maxLod, tObj->Image[0][minLod]->MaxLog2 + minLod);
+			maxLod = MIN2(maxLod, tObj->Image[0][minLod]->MaxNumLevels - 1 + minLod);
 			maxLod = MAX2(maxLod, minLod); /* need at least one level */
 		}
 		break;
@@ -329,7 +329,7 @@ static GLboolean radeon_miptree_matches_texture(radeon_mipmap_tree *mt, struct g
 
 	mtBaseLevel = &mt->levels[texObj->BaseLevel - mt->baseLevel];
 	firstImage = texObj->Image[0][texObj->BaseLevel];
-	numLevels = MIN2(texObj->_MaxLevel - texObj->BaseLevel + 1, firstImage->MaxLog2 + 1);
+	numLevels = MIN2(texObj->_MaxLevel - texObj->BaseLevel + 1, firstImage->MaxNumLevels);
 
 	if (radeon_is_debug_enabled(RADEON_TEXTURE,RADEON_TRACE)) {
 		fprintf(stderr, "Checking if miptree %p matches texObj %p\n", mt, texObj);
@@ -378,7 +378,7 @@ void radeon_try_alloc_miptree(radeonContextPtr rmesa, radeonTexObj *t)
 	}
 
 
-	numLevels = MIN2(texObj->MaxLevel - texObj->BaseLevel + 1, texImg->MaxLog2 + 1);
+	numLevels = MIN2(texObj->MaxLevel - texObj->BaseLevel + 1, texImg->MaxNumLevels);
 
 	t->mt = radeon_miptree_create(rmesa, t->base.Target,
 		texImg->TexFormat, texObj->BaseLevel,

src/mesa/main/mtypes.h

@@ -1205,7 +1205,8 @@ struct gl_texture_image
    GLuint WidthLog2;		/**< = log2(Width2) */
    GLuint HeightLog2;		/**< = log2(Height2) */
    GLuint DepthLog2;		/**< = log2(Depth2) */
-   GLuint MaxLog2;		/**< = MAX(WidthLog2, HeightLog2) */
+   GLuint MaxNumLevels;		/**< = maximum possible number of mipmap
+                                       levels, computed from the dimensions */
 
    struct gl_texture_object *TexObject;  /**< Pointer back to parent object */
    GLuint Level;                /**< Which mipmap level am I? */

src/mesa/main/teximage.c

@@ -1002,6 +1002,43 @@ _mesa_get_texture_dimensions(GLenum target)
 }
 
 
+/**
+ * Return the maximum number of mipmap levels for the given target
+ * and the dimensions.
+ * The dimensions are expected not to include the border.
+ */
+GLsizei
+_mesa_get_tex_max_num_levels(GLenum target, GLsizei width, GLsizei height,
+                             GLsizei depth)
+{
+   GLsizei size;
+
+   switch (target) {
+   case GL_TEXTURE_1D:
+   case GL_TEXTURE_1D_ARRAY:
+      size = width;
+      break;
+   case GL_TEXTURE_CUBE_MAP:
+   case GL_TEXTURE_CUBE_MAP_ARRAY:
+      ASSERT(width == height);
+      size = width;
+      break;
+   case GL_TEXTURE_2D:
+   case GL_TEXTURE_2D_ARRAY:
+      size = MAX2(width, height);
+      break;
+   case GL_TEXTURE_3D:
+      size = MAX3(width, height, depth);
+      break;
+   case GL_TEXTURE_RECTANGLE:
+      return 1;
+   default:
+      assert(0);
+      return 1;
+   }
+
+   return _mesa_logbase2(size) + 1;
+}
 
 
 #if 000 /* not used anymore */
@@ -1187,7 +1224,9 @@ _mesa_init_teximage_fields(struct gl_context *ctx,
                     target);
    }
 
-   img->MaxLog2 = MAX2(img->WidthLog2, img->HeightLog2);
+   img->MaxNumLevels =
+      _mesa_get_tex_max_num_levels(target,
+                                   img->Width2, img->Height2, img->Depth2);
    img->TexFormat = format;
 }
 

src/mesa/main/teximage.h

@@ -138,6 +138,10 @@ _mesa_tex_target_to_face(GLenum target);
 extern GLint
 _mesa_get_texture_dimensions(GLenum target);
 
+extern GLsizei
+_mesa_get_tex_max_num_levels(GLenum target, GLsizei width, GLsizei height,
+                             GLsizei depth);
+
 extern GLenum
 _mesa_es_error_check_format_and_type(GLenum format, GLenum type,
                                      unsigned dimensions);