## ----include = FALSE----------------------------------------------------------
knitr::opts_chunk$set(
  collapse = TRUE,
  comment = "#>"
)
knitr::opts_chunk$set(
  fig.width = 7,
  fig.height = 5,
  fig.align = "center"
)

## ----setup--------------------------------------------------------------------
library(sf)
library(ggplot2)
library(mapycusmaximus)
theme_set(ggplot2::theme_minimal())

## ----quick-start--------------------------------------------------------------
# Focus near a supplied geometry: use the centroid of the combined Melbourne polygon
melbourne <- vic[vic$LGA_NAME == "MELBOURNE", ]

vic_fisheye_demo <- sf_fisheye(
  vic,
  center = melbourne,      # accept sf/sfc; centroid is used in working CRS
  r_in = 0.34, r_out = 0.60,
  zoom_factor = 15,
  squeeze_factor = 0.35,
  method = "expand",
  revolution = 0
)

ggplot() +
  geom_sf(data = vic_fisheye_demo, fill = "grey92", color = "white", linewidth = 0.2) +
  geom_sf(data = melbourne, fill = NA, color = "tomato", linewidth = 0.5) +
  ggtitle("FGC fisheye: Melbourne focus within Victoria")

## ----centers------------------------------------------------------------------
# Example: WGS84 center (Melbourne CBD), auto-project to a working CRS
vic_cbd <- sf_fisheye(
  vic,
  center = c(144.9631, -37.8136),
  center_crs = "EPSG:4326",
  r_in = 0.30, r_out = 0.55,
  zoom_factor = 15, squeeze_factor = 0.30
)

ggplot(vic_cbd) +
  geom_sf(fill = "grey92", color = "white", linewidth = 0.2) +
  ggtitle("Center supplied as lon/lat (WGS84)")

## ----multi-layer--------------------------------------------------------------
centroids <- st_centroid(vic)
vic$layer <- "polygon"
centroids$layer <- "centroid"
both <- rbind(vic[, c("LGA_NAME", "geometry", "layer")],
              centroids[, c("LGA_NAME", "geometry", "layer")])

both_fish <- sf_fisheye(both, center = melbourne,
                        r_in = 0.34, r_out = 0.60,
                        zoom_factor = 15, squeeze_factor = 0.35)

ggplot() +
  geom_sf(data = both_fish[both_fish$layer == "polygon", ],
          fill = "grey92", color = "white", linewidth = 0.2) +
  geom_sf(data = both_fish[both_fish$layer == "centroid", ],
          color = "#2b6cb0", size = 0.6, alpha = 0.8) +
  ggtitle("Aligned overlays: transform layers together, plot separately")

## ----scale-radii, eval=FALSE--------------------------------------------------
# all_points <- sf_fisheye(all_points, center = melbourne,
#                          zoom_factor = 1.8, squeeze_factor = 0.30)
# scale_radii <- 1 - (((st_bbox(vic)["xmax"] - st_bbox(vic)["xmin"])  -
#                      (st_bbox(all_points)["xmax"] - st_bbox(all_points)["xmin"])) /
#                     (st_bbox(vic)["xmax"] - st_bbox(vic)["xmin"]))
# vic_fisheye <- sf_fisheye(vic, center = melbourne,
#                           r_in = 0.35 * scale_radii,
#                           r_out = 0.50 * scale_radii,
#                           zoom_factor = 1.8, squeeze_factor = 0.30)

## ----diagnostics--------------------------------------------------------------
grid <- create_test_grid(range = c(-1, 1), spacing = 0.1)
warp <- fisheye_fgc(grid, r_in = 0.34, r_out = 0.5,
                    zoom_factor = 1.3, squeeze_factor = 0.5)
plot_fisheye_fgc(grid, warp, r_in = 0.34, r_out = 0.5)