## ----include = FALSE----------------------------------------------------------
knitr::opts_chunk$set(collapse = TRUE, comment = "#>", fig.width = 7, fig.height = 4)

## ----setup, message = FALSE---------------------------------------------------
library(blueterra)
library(terra)

## ----data---------------------------------------------------------------------
bathy <- read_bathy(blueterra_example("hitw"))
rectangles <- terra::vect(blueterra_example("sampling_rectangles"))
hitw_rect <- rectangles[rectangles$site_id == "hitw", ]

prepared <- prepare_bathy(
  bathy,
  depth_range = c(-220, -25),
  smooth = TRUE
)

estimate_surface_orientation(prepared, hitw_rect)

## ----automatic----------------------------------------------------------------
transects <- make_transects(
  hitw_rect,
  spacing = 75,
  bathy = prepared
)

transects[, c("transect_id", "angle_deg", "angle_source", "mean_aspect_deg")]

## ----automatic-map, eval=requireNamespace("ggplot2", quietly = TRUE), fig.alt="Automatically oriented transects over hillshaded bathymetry."----
plot_transects(
  prepared,
  transects,
  color_by = "transect_id",
  show_legend = FALSE,
  contour_interval = 25,
  title = "Terrain-Oriented Transects",
  subtitle = "Line angle estimated from local surface aspect"
)

## ----manual-------------------------------------------------------------------
manual_transects <- make_transects(
  hitw_rect,
  spacing = 75,
  angle = 45
)

manual_transects[, c("transect_id", "angle_deg", "angle_source")]

## ----sample-------------------------------------------------------------------
samples <- sample_transects(transects, prepared, n = 12)
sections <- extract_cross_sections(transects, prepared, n = 12)

head(samples[, c("transect_id", "distance", "x", "y", "bathy_m")])
summarize_cross_sections(samples, value_col = "bathy_m")
identical(names(samples), names(sections))

## ----cross-section-plot, eval=requireNamespace("ggplot2", quietly = TRUE), fig.alt="Bathymetric cross-sections with bathy_m on the y-axis."----
plot_cross_sections(
  samples,
  value_col = "bathy_m",
  show_legend = TRUE,
  mean_profile = TRUE,
  mean_profile_na_rm = TRUE,
  normalize_distance = FALSE,
  profile_direction = "top_to_bottom",
  title = "Bathymetric Cross-Sections",
  subtitle = "Profiles read from shallow to deep terrain"
)

## ----profile, eval=requireNamespace("ggplot2", quietly = TRUE), fig.alt="Bathymetric profile along a single transect."----
one <- samples[samples$transect_id == samples$transect_id[1], ]

plot_depth_profile(
  one,
  value_col = "bathy_m",
  profile_direction = "top_to_bottom",
  title = "Bathymetry Along One Transect"
)

## ----slope-profile, eval=requireNamespace("ggplot2", quietly = TRUE), fig.alt="Slope profile along one transect."----
metrics <- derive_terrain(prepared, metrics = c("slope", "tri", "bpi"))
metric_samples <- sample_transects(
  transects,
  c(prepared, metrics[["slope_deg"]]),
  n = 25
)
metric_one <- metric_samples[metric_samples$transect_id == metric_samples$transect_id[1], ]

plot_depth_profile(
  metric_one,
  depth_col = "bathy_m",
  value_col = "slope_deg",
  profile_direction = "top_to_bottom",
  title = "Slope Along Depth"
)