First attempt at 3d track

Author: Max Czapanskiy

NAMESPACE

@@ -2,5 +2,6 @@
 
 export(read_nc)
 export(view_cats)
+export(view_cats_3d)
 import(dplyr)
 import(ggplot2)

R/viz.R

@@ -54,3 +54,45 @@ make_subplot <- function(var, prh) {
             legend.title = element_blank())) %>%
     plotly::ggplotly(dynamicTicks = TRUE)
 }
+
+#' Plot a georeferenced track in 3d
+#'
+#' @param prh A CATS PRH object
+#' @param width Width of the track (in meters)
+#'
+#' @return A plotly 3d mesh figure
+#' @export
+#'
+#' @examples
+#' view_cats_3d(mn200312_58, width = 10)
+view_cats_3d <- function(prh, width = 1) {
+  # Calculate points for a 3d ribbon path
+  prh$z <- -prh$z
+  wx <- lead(prh$x) - prh$x
+  wy <- lead(prh$y) - prh$y
+  wz <- lead(prh$z) - prh$z
+  wnorm <- apply(cbind(wx, wy, wz), 1, function(vec) sqrt(sum(vec^2)))
+  wx <- wx / wnorm * width
+  wy <- wy / wnorm * width
+  wz <- wz / wnorm * width
+  cosp <- cos(prh$pitch)
+  cosr <- cos(prh$roll)
+  sinp <- sin(prh$pitch)
+  sinr <- sin(prh$roll)
+  px <- head(wy * cosp * sinr - wz * cosr, -1)
+  py <- head(wz * sinp * sinr - wx * cosp * sinr, -1)
+  pz <- head(wx * cosr - wy * sinp * sinr, -1)
+  x0 <- head(prh$x, -1)
+  y0 <- head(prh$y, -1)
+  z0 <- head(prh$z, -1)
+  x <- c(x0 + px, x0 - px)
+  y <- c(y0 + py, y0 - py)
+  z <- c(z0 + pz, z0 - pz)
+  n <- nrow(prh) - 1
+  i <- rep(1:(n - 1), each = 2) + rep(c(0, n), n - 1) - 1
+  j <- rep(1:(n - 1), each = 2) + rep(c(n, 1), n - 1) - 1
+  k <- rep(2:n, each = 2) + rep(c(0, n), n - 1) - 1
+  plotly::plot_ly(type = "mesh3d",
+                  x = x, y = y, z = z,
+                  i = i, j = j, k = k)
+}