R/drawHiveSpline.R

In HiveR: 2D and 3D Hive Plots for R

#' Draw a 3D Spline as Part of a 3D Hive Plot
#'
#' This function analyzes the edges of a \code{HivePlotData} object in order to
#' draw 3D splines representing those edges.  Each pair of nodes at the ends of
#' an edge is identified, and a control point is computed.  This information is
#' passed to \code{\link{rcsr}} to work out the details.
#'
#'
#' @param HPD An object of S3 class \code{HivePlotData}.
#'
#' @param L_A Logical: should splines be drawn with \code{line_antialias =
#' TRUE}?
#'
#' @param \dots Parameters to be passed downstream.
#'
#' @return None.  A spline is added to the 3D hive plot in progress.
#'
#' @author Bryan A. Hanson, DePauw University. \email{hanson@@depauw.edu}
#'
#' @seealso \code{\link{plot3dHive}} which calls this function and is the user
#' interface.
#'
#' @keywords plot hplot
#'
#' @export drawHiveSpline
#'
#' @importFrom rgl lines3d
#'
drawHiveSpline <- function(HPD, L_A = FALSE, ...) {

  # Function to locate a 3d spline curve in a particular n dimensional
  # system & figure out the control point

  # For use with plot3dHive
  # Bryan Hanson, DePauw University, Feb 2011 and onward

  if (!requireNamespace("rgl", quietly = TRUE)) {
    stop("You need to install package rgl to use this function")
  }

  # The point pairs to be connected given by df edges

  chkHPD(HPD)
  nodes <- HPD$nodes
  edges <- HPD$edges
  nx <- length(unique(nodes$axis))
  if ((nx == 2) | (nx == 3)) stop("You shouldn't be calling this function w/2 or 3 axes")

  ##### Get the edges data frame ready

  ax1 <- rad1 <- ax2 <- rad2 <- c()

  for (n in 1:nrow(edges)) {
    pat1 <- paste("\\b", edges$id1[n], "\\b", sep = "")
    pat2 <- paste("\\b", edges$id2[n], "\\b", sep = "")
    id1 <- grep(pat1, nodes$id)
    id2 <- grep(pat2, nodes$id)

    ax1 <- c(ax1, nodes$axis[id1])
    rad1 <- c(rad1, nodes$radius[id1])
    ax2 <- c(ax2, nodes$axis[id2])
    rad2 <- c(rad2, nodes$radius[id2])
  }

  ds <- data.frame(ax1, rad1, ax2, rad2)
  ds$phi1 <- ds$phi2 <- ds$th1 <- ds$th2 <- rep(NA, length(ds$ax1))

  ##### 4D, This requires a 3D spline curve to be drawn

  if (nx == 4) {
    for (n in 1:nrow(ds)) {
      if (ds$ax1[n] == 1) {
        ds$phi1[n] <- 54.7
        ds$th1[n] <- 45
      }
      if (ds$ax1[n] == 2) {
        ds$phi1[n] <- 125.3
        ds$th1[n] <- -45
      }
      if (ds$ax1[n] == 3) {
        ds$phi1[n] <- 125.3
        ds$th1[n] <- 135
      }
      if (ds$ax1[n] == 4) {
        ds$phi1[n] <- 54.7
        ds$th1[n] <- -135
      }

      if (ds$ax2[n] == 1) {
        ds$phi2[n] <- 54.7
        ds$th2[n] <- 45
      }
      if (ds$ax2[n] == 2) {
        ds$phi2[n] <- 125.3
        ds$th2[n] <- -45
      }
      if (ds$ax2[n] == 3) {
        ds$phi2[n] <- 125.3
        ds$th2[n] <- 135
      }
      if (ds$ax2[n] == 4) {
        ds$phi2[n] <- 54.7
        ds$th2[n] <- -135
      }
    }

    pt1 <- data.frame(radius = ds$rad1, theta = ds$th1, phi = ds$phi1)
    pt2 <- data.frame(radius = ds$rad2, theta = ds$th2, phi = ds$phi2)
    pt1 <- sph2cart(pt1)
    pt2 <- sph2cart(pt2)

    # Compute control point, then create splines
    # Splines must be drawn one at a time (slow!)

    cp <- 0.6 * (pt1 + pt2)

    pt1 <- as.matrix(pt1)
    cp <- as.matrix(cp)
    pt2 <- as.matrix(pt2)

    for (n in 1:nrow(pt1)) {
      spl <- rcsr(p0 = pt1[n, ], cp = cp[n, ], p1 = pt2[n, ])
      rgl::lines3d(
        x = spl[, 1], y = spl[, 2], z = spl[, 3],
        line_antialias = L_A, col = edges$color[n], lwd = edges$weight[n]
      )
    }
  } # end of nx = 4

  ##### 5D, This requires a 3D spline curve to be drawn

  if (nx == 5) {
    for (n in 1:nrow(ds)) {
      if (ds$ax1[n] == 1) {
        ds$phi1[n] <- 90
        ds$th1[n] <- 0
      }
      if (ds$ax1[n] == 2) {
        ds$phi1[n] <- 90
        ds$th1[n] <- 120
      }
      if (ds$ax1[n] == 3) {
        ds$phi1[n] <- 90
        ds$th1[n] <- 240
      }
      if (ds$ax1[n] == 4) {
        ds$phi1[n] <- 0
        ds$th1[n] <- 0
      }
      if (ds$ax1[n] == 5) {
        ds$phi1[n] <- 180
        ds$th1[n] <- 0
      }

      if (ds$ax2[n] == 1) {
        ds$phi2[n] <- 90
        ds$th2[n] <- 0
      }
      if (ds$ax2[n] == 2) {
        ds$phi2[n] <- 90
        ds$th2[n] <- 120
      }
      if (ds$ax2[n] == 3) {
        ds$phi2[n] <- 90
        ds$th2[n] <- 240
      }
      if (ds$ax2[n] == 4) {
        ds$phi2[n] <- 0
        ds$th2[n] <- 0
      }
      if (ds$ax2[n] == 5) {
        ds$phi2[n] <- 180
        ds$th2[n] <- 0
      }
    }

    pt1 <- data.frame(radius = ds$rad1, theta = ds$th1, phi = ds$phi1)
    pt2 <- data.frame(radius = ds$rad2, theta = ds$th2, phi = ds$phi2)
    pt1 <- sph2cart(pt1)
    pt2 <- sph2cart(pt2)

    # Compute control point, then create splines
    # Splines must be drawn one at a time (slow!)

    cp <- 0.6 * (pt1 + pt2)

    pt1 <- as.matrix(pt1)
    cp <- as.matrix(cp)
    pt2 <- as.matrix(pt2)
    for (n in 1:nrow(pt1)) {
      spl <- rcsr(p0 = pt1[n, ], cp = cp[n, ], p1 = pt2[n, ])
      rgl::lines3d(
        x = spl[, 1], y = spl[, 2], z = spl[, 3],
        line_antialias = L_A, col = edges$color[n], lwd = edges$weight[n]
      )
    }
  } # end of nx = 5

  ##### 6D, This requires a 3D spline curve to be drawn

  if (nx == 6) {
    for (n in 1:nrow(ds)) {
      if (ds$ax1[n] == 1) {
        ds$phi1[n] <- 90
        ds$th1[n] <- 0
      }
      if (ds$ax1[n] == 2) {
        ds$phi1[n] <- 90
        ds$th1[n] <- 90
      }
      if (ds$ax1[n] == 3) {
        ds$phi1[n] <- 90
        ds$th1[n] <- 180
      }
      if (ds$ax1[n] == 4) {
        ds$phi1[n] <- 90
        ds$th1[n] <- 270
      }
      if (ds$ax1[n] == 5) {
        ds$phi1[n] <- 0
        ds$th1[n] <- 0
      }
      if (ds$ax1[n] == 6) {
        ds$phi1[n] <- 180
        ds$th1[n] <- 0
      }

      if (ds$ax2[n] == 1) {
        ds$phi2[n] <- 90
        ds$th2[n] <- 0
      }
      if (ds$ax2[n] == 2) {
        ds$phi2[n] <- 90
        ds$th2[n] <- 90
      }
      if (ds$ax2[n] == 3) {
        ds$phi2[n] <- 90
        ds$th2[n] <- 180
      }
      if (ds$ax2[n] == 4) {
        ds$phi2[n] <- 90
        ds$th2[n] <- 270
      }
      if (ds$ax2[n] == 5) {
        ds$phi2[n] <- 0
        ds$th2[n] <- 0
      }
      if (ds$ax2[n] == 6) {
        ds$phi2[n] <- 180
        ds$th2[n] <- 0
      }
    }

    pt1 <- data.frame(radius = ds$rad1, theta = ds$th1, phi = ds$phi1)
    pt2 <- data.frame(radius = ds$rad2, theta = ds$th2, phi = ds$phi2)
    pt1 <- sph2cart(pt1)
    pt2 <- sph2cart(pt2)

    # Compute control point, then create splines
    # Splines must be drawn one at a time (slow!)

    cp <- 0.6 * (pt1 + pt2)

    pt1 <- as.matrix(pt1)
    cp <- as.matrix(cp)
    pt2 <- as.matrix(pt2)
    for (n in 1:nrow(pt1)) {
      spl <- rcsr(p0 = pt1[n, ], cp = cp[n, ], p1 = pt2[n, ])
      rgl::lines3d(
        x = spl[, 1], y = spl[, 2], z = spl[, 3],
        line_antialias = L_A, col = edges$color[n], lwd = edges$weight[n]
      )
    }
  } # end of nx = 6
} # closing brace, this is the very end!