+/**
+ * Prepare all mipmap levels beyond 'baseLevel' for mipmap generation.
+ * When finished, all the gl_texture_image structures for the smaller
+ * mipmap levels will be consistent with the base level (in terms of
+ * dimensions, format, etc).
+ */
+void
+_mesa_prepare_mipmap_levels(struct gl_context *ctx,
+ struct gl_texture_object *texObj,
+ unsigned baseLevel, unsigned maxLevel)
+{
+ const struct gl_texture_image *baseImage =
+ _mesa_select_tex_image(texObj, texObj->Target, baseLevel);
+ const GLint border = 0;
+ GLint width = baseImage->Width;
+ GLint height = baseImage->Height;
+ GLint depth = baseImage->Depth;
+ const GLenum intFormat = baseImage->InternalFormat;
+ const mesa_format texFormat = baseImage->TexFormat;
+ GLint newWidth, newHeight, newDepth;
+
+ /* Prepare baseLevel + 1, baseLevel + 2, ... */
+ for (unsigned level = baseLevel + 1; level <= maxLevel; level++) {
+ if (!_mesa_next_mipmap_level_size(texObj->Target, border,
+ width, height, depth,
+ &newWidth, &newHeight, &newDepth)) {
+ /* all done */
+ break;
+ }
+
+ if (!prepare_mipmap_level(ctx, texObj, level,
+ newWidth, newHeight, newDepth,
+ border, intFormat, texFormat)) {
+ break;
+ }
+
+ width = newWidth;
+ height = newHeight;
+ depth = newDepth;
+ }
+}
+
+