scene3d <- function(minimal = TRUE) {
  
  saveSubscene <- currentSubscene3d()
  on.exit(useSubscene3d(saveSubscene))
  
  defaultmaterial <- material3d()
  
  matdiff <- function(mat) {
    for (m in names(mat)) {
      if (identical(mat[[m]], defaultmaterial[[m]]))
        mat[[m]] <- NULL
    }
    mat
  }
  
  getObject <- function(id, type) {
    result <- list(id=id, type=type)
    
    if (!(type %in% c("light", "clipplanes"))) {
      mat <- rgl.getmaterial(id=id)
      lit <- mat$lit
      result$material <- matdiff(mat)
    } else
      lit <- FALSE
    
    attribs <- c("vertices", "colors", "texcoords", "dim",
          "texts", "cex", "adj", "radii", "ids",
          "usermatrix", "types", "offsets", "centers",
          "family", "font", "pos")
    if (lit || !minimal || type %in% c("light", "clipplanes"))
      attribs <- c(attribs, "normals")
    for (a in attribs) 
      if (rgl.attrib.count(id, a))
        result[[a]] <- rgl.attrib(id, a)
    flags <- rgl.attrib(id, "flags")
    if (length(flags)) {
    	if ("ignoreExtent" %in% rownames(flags)) 
          result$ignoreExtent <- flags["ignoreExtent", 1]
    	if ("fixedSize" %in% rownames(flags))
    	  result$fixedSize <- flags["fixedSize", 1]
    	if ("fastTransparency" %in% rownames(flags))
    	  result$fastTransparency <- flags["fastTransparency", 1]
    	if ("flipped" %in% rownames(flags))
    	  result$flipped <- flags["flipped", 1]
    }
    if (!is.null(result$ids)) {
      objlist <- vector("list", nrow(result$ids))
      for (i in seq_len(nrow(result$ids)))
        objlist[[i]] <- getObject(result$ids[i,1], result$types[i,1])
      result$objects <- objlist
    }
    if (type == "background") {
      flags <- rgl.attrib(id, "flags")
      result$sphere <- flags["sphere", 1]
      result$fogtype <- if (flags["linear_fog", 1]) "linear"
                        else if (flags["exp_fog", 1]) "exp"
			else if (flags["exp2_fog", 1]) "exp2"
			else "none"
      result$fogscale <- rgl.attrib(id, "fogscale")
    } else if (type == "bboxdeco") {
      flags <- rgl.attrib(id, "flags")
      result$draw_front <- flags["draw_front", 1]
    } else if (type == "light") {
      flags <- rgl.attrib(id, "flags")
      result$viewpoint <- flags["viewpoint", 1]
      result$finite    <- flags["finite", 1]
    }
    class(result) <- c(paste0("rgl", type), "rglobject")
    result
  }

  getSubscene <- function(id) {
    useSubscene3d(id)
      
    result <- list(id = id, type = "subscene", par3d = par3d())

    result$embeddings <- subsceneInfo()$embeddings
    
    objs <- ids3d(c("background", "bboxdeco", "shapes", "lights"))
    result$objects <- objs$id
  
    if (nrow(obj <- ids3d("subscene", subscene = id))) {
      subscenes <- vector("list", nrow(obj))
      ids <- obj$id
      for (i in seq_len(nrow(obj)))
        subscenes[[i]] <- getSubscene(ids[i])
      result$subscenes <- subscenes
    }
    class(result) <- c("rglsubscene", "rglobject")
    result
  }
  
  result <- list()
  result$material <- defaultmaterial
  
  result$rootSubscene <- getSubscene(rootSubscene())
  
  objs <- ids3d(c("shapes", "lights", "background", "bboxdeco"), subscene=0)  
  objlist <- vector("list", nrow(objs))
  ids <- objs$id
  types <- as.character(objs$type)
  for (i in seq_len(nrow(objs))) {
    objlist[[i]] <- getObject(ids[i], types[i])
    names(objlist)[i] <- as.character(ids[i])
  }
  result$objects <- objlist
    
  class(result) <- "rglscene"
  result
}

print.rglscene <- function(x, ...) {
  cat(gettext("RGL scene containing:\n"))
  if (!is.null(x$par3d))
    cat(gettext("  par3d:\tscene information\n"))
  if (!is.null(x$material))
    cat(gettext("  material:\tdefault material properties\n"))
  if (!is.null(x$objects)) {
    cat(gettextf("  objects:\tlist of %d object(s):\n", length(x$objects)))
    cat("          \t", sapply(x$objects, function(obj) obj$type), "\n")
  }
  if (!is.null(x$root)) 
    cat(gettext("  root:\ta root subscene\n"))
  invisible(x)
}

summary.rglscene <- function(object, ...) {
  result <- list()
  nobjs <- length(object$objects)
  if (nobjs) result$objects <- data.frame(type=sapply(object$objects, function(obj) obj$type))
  if (!is.null(object$rootSubscene))
    result$subscenes <- summary(object$rootSubscene)
  result
}

summary.rglsubscene <- function(object, ...) {
  result <- data.frame(id = object$id, parent = NA, objects = 0)
  result$objects <- list(object$objects)
  if (length(object$subscenes)) {
    children <- do.call(rbind, lapply(object$subscenes, summary))
    children[is.na(children$parent),"parent"] <- object$id
    result <- rbind(result, children)
  }
  result
}

print.rglobject <- function(x, ...) {
  cat(gettextf("RGL object of type %s containing components\n", x$type))
  cat("  ")
  cat(names(x), sep=", ")
  cat("\n")
}

print.rglsubscene <- function(x, ...) {
  cat(gettext("RGL subscene containing components\n"))
  cat("  ")
  cat(names(x), sep=", ")
  cat("\n")
}
  

plot3d.rglscene <- function(x, add=FALSE, ...) {
  root <- x$rootSubscene
  if (is.null(root)) root <- x  # Should work with pre-subscene objects
  if (!add) {
    params <- getr3dDefaults()
    if (!is.null(x$material)) {
      if (is.null(params$material)) params$material <- list()
      params$material[names(x$material)] <- x$material
    }
    if (!is.null(root$bg)) {
      if (is.null(params$bg)) params$bg <- list()
      params$bg[names(params$material)] <- params$material
      params$bg[names(x$bg$material)] <- x$bg$material
      x$bg$material <- x$bg$id <- x$bg$type <- NULL
      params$bg[names(x$bg)] <- x$bg
    }
    if (!is.null(root$par3d)) {
      ind <- !(names(root$par3d) %in% .Par3d.readonly)
      params[names(root$par3d)[ind]] <- root$par3d[ind]
    }
    open3d(params = params)
    
    # Some older scenes might not have a light in them, so only clear if one is there
    for (i in seq_along(x$objects)) {
      obj <- x$objects[[i]]
      if (obj$type == "light") {
        clear3d("lights")
        break
      }
    }
  } 
  save <- par3d(skipRedraw = TRUE)
  on.exit(par3d(save))
  
  if (is.null(x$rootSubscene)) {
    results <- NULL
    for (i in seq_along(x$objects)) {
      obj <- x$objects[[i]]
      results <- c(results, plot3d(obj))
    }
    if (!is.null(obj <- x$bbox)) 
      plot3d(obj)  
  } else 
    results <- plot3d(root, x$objects, root = TRUE, ...)
  
  highlevel(results)
}   

plot3d.rglsubscene <- function(x, objects, root = TRUE, ...) {
  if (root) {
    if (!is.null(x$embeddings)) {
      info <- subsceneInfo(embeddings = x$embeddings)
      subscene <- info$id
    } else
      subscene <- currentSubscene3d()
    if (!is.null(x$par3d$viewport))
      par3d(viewport = x$par3d$viewport)
  } else
    subscene <- newSubscene3d(viewport = x$embeddings["viewport"],
			    projection = x$embeddings["projection"],
			    model = x$embeddings["model"],
			    newviewport = x$par3d$viewport,
			    copyLights = FALSE)
			   
  if (!is.null(x$par3d$scale))
    par3d(scale = x$par3d$scale)
  listeners <- list(x$par3d$listeners) # list contains old ids
  names(listeners) <- subscene         # names are new ids
    
  results <- subscene
  names(results) <- paste0("subscene", as.character(x$id))
  
  objs <- x$objects
  for (id in as.character(objs)) {
    obj <- objects[[id]]
    if (is.null(obj$newid)) 
      results <- c(results, objects[[id]]$newid <- plot3d(obj, ...))
    else
      addToSubscene3d(obj$newid)
  }
  for (i in seq_along(x$subscenes)) {
    useSubscene3d(subscene)
    res <- plot3d(x$subscenes[[i]], objects, root=FALSE, ...)
    results <- c(results, res$results)
    listeners <- c(listeners, res$listeners)
    objects <- res$objects
  }
  if (root) {
    # Translate all the listener values
    dotranslations <- function(id) {
      info <- subsceneInfo(id = id)
      oldlisteners <- listeners[[as.character(id)]]
      par3d(listeners = results[paste0("subscene", oldlisteners)], subscene = id)
      for (child in info$children)
        dotranslations(child)
    }
    dotranslations(subscene)
    return(results)
  } else
    return(list(results=results, objects=objects, listeners=listeners))
}

plot3d.rglobject <- function(x, ...) {
  type <- x$type
  fn <- switch(type,
    points = points3d,
    lines = segments3d,
    linestrip = lines3d,
    triangles = triangles3d,
    quads = quads3d,
    text = texts3d,
    spheres = spheres3d,
    abclines = abclines3d,
    planes = planes3d,
    surface = surface3d,
    sprites = sprites3d,
    light = light3d,
    clipplanes = clipplanes3d,
    NULL)
  if (is.null(fn)) {
    warning(gettextf("Object type '%s' not handled.", type), 
    	    domain = NA)
    return()
  }
  if (!is.null(x$ignoreExtent)) {
    save <- par3d(ignoreExtent = x$ignoreExtent)
    on.exit(par3d(save))
  }
  args <- list()
  args$x <- x$vertices
  args$normals <- x$normals
  args$texcoords <- x$texcoords
  args$texts <- x$texts
  args$cex <- x$cex
  args$adj <- x$adj
  args$radius <- x$radii
  args$d <- x$offsets
  
  switch(type, 
    abclines = {
      odd <- seq_len(nrow(args$x)) %% 2 == 1
      ends <- args$x[odd,,drop=FALSE]
      args$a <- args$x[!odd,,drop=FALSE] - ends
      args$x <- ends
    },
    planes =,
    clipplanes = {
      args$a <- args$normals
      args$x <- NULL
      args$normals <- NULL
    },  
    surface = {
      dim <- x$dim
      args$y <- matrix(args$x[,2], dim[1], dim[2])
      args$z <- matrix(args$x[,3], dim[1], dim[2])
      args$x <- matrix(args$x[,1], dim[1], dim[2])
      if (!is.null(args$normals)) {
        args$normal_x <- matrix(args$normals[,1], dim[1], dim[2])
	args$normal_y <- matrix(args$normals[,2], dim[1], dim[2])
	args$normal_z <- matrix(args$normals[,3], dim[1], dim[2])
        args$normals <- NULL
      }
      if (!is.null(args$texcoords)) {
        args$texture_s <- matrix(args$texcoords[,1], dim[1], dim[2])
        args$texture_t <- matrix(args$texcoords[,2], dim[1], dim[2])
        args$texcoords <- NULL
      }
    },
    sprites = {
      save2 <- par3d(skipRedraw = TRUE)
      on.exit(par3d(save2), add=TRUE)
  
      if (!is.null(x$objects)) {
        ids <- numeric(length(x$objects))
        for (i in seq_along(ids)) 
          ids[i] <- plot3d(x$objects[[i]])
        args$shapes <- ids
      }
      args$userMatrix <- x$usermatrix
    })
      
  mat <- x$material
  if (is.null(mat)) mat <- list()
  if (!is.null(col <- x$colors)) {
    mat$color <- rgb(col[,1], col[,2], col[,3])
    mat$alpha <- col[,4]
  }

  if (type == "light") {
    if (!x$finite) {
      args$x <- NULL
      vx <- x$vertices[1]
      vy <- x$vertices[2]
      vz <- x$vertices[3]
      args$phi <- atan2(vy, sqrt(vx^2 + vz^2))*180/pi
      args$theta <- atan2(vx, vz)*180/pi
    }
    args$viewpoint.rel <- x$viewpoint
    args$ambient <- mat$color[1]
    args$diffuse <- mat$color[2]
    args$specular <- mat$color[3]
  } else 
    args <- c(args, mat)
  
  do.call(fn, args)
}

plot3d.rglbboxdeco <- function(x, ...) {
  args <- list()     
  v <- x$vertices
  t <- x$texts
  ind <- is.na(v[,2]) & is.na(v[,3])
  if (any(ind)) {
    args$xat <- v[ind,1]
    if (!is.null(t))
      args$xlab <- t[ind]
    else
      args$xlab <- signif(args$xat, 4)
  }
  ind <- is.na(v[,1]) & is.na(v[,3])
  if (any(ind)) {
    args$yat <- v[ind,2]
    if (!is.null(t))
      args$ylab <- t[ind]
    else
      args$ylab <- signif(args$yat, 4)
  }
  ind <- is.na(v[,1]) & is.na(v[,2])
  if (any(ind)) {
    args$zat <- v[ind,3]
    if (!is.null(t))
      args$zlab <- t[ind]
    else
      args$zlab <- signif(args$zat, 4)
  }
  args$draw_front <- x$draw_front
  args <- c(args, x$material)
  
  do.call("bbox3d", args)
}

plot3d.rglbackground <- function(x, ...) {
  mat <- x$material 
  if (is.null(mat)) mat <- list()
  if (!is.null(col <- x$colors)) {
    mat$color <- rgb(col[,1], col[,2], col[,3])
    mat$alpha <- col[,4]
  }
  args <- c(list(sphere = x$sphere, fogtype = x$fogtype), mat)
  do.call("bg3d", args)
}

plot3d.rglWebGL <- function(x, ...) {
  plot3d(attr(x, "origScene"), ...)
}
