anglr+silicate_elevate_polygons_image.md

#remotes::install_cran(c("anglr", "silicate"))

library(silicate)
library(anglr)
library(rgl)
## volcano is heightmap, doesn't exist in geo-space in R so we map it do the extent of
## these spatial polygons 
poly <- silicate::minimal_mesh
# xmin       : 0 
# xmax       : 1.23 
# ymin       : 0 
# ymax       : 1 

## arbitrarily drape polygons over raster
hmap <- raster::setExtent(raster::raster(volcano), raster::extent(0, 1.23, 0, 1))

## use DEL0 so we can control triangle area (not possible with decido, without
## post-hoc subdivision)
triangles <- copy_down(DEL0(poly, max_area = 0.001), hmap)


mesh1 <- as.mesh3d(triangles)


open3d();plot3d(mesh1)
aspect3d(1, 1, 0.5)


# that was just polygons + raster, so now make an image from the raster and
# texture it on (this could be a photograph, a map, just needs to be a 3-layer RGB raster)
im <- palr::image_raster(hmap, col = viridis::viridis(32))

mesh2 <- as.mesh3d(triangles, image_texture = im)

open3d(); plot3d(mesh2)
aspect3d(1, 1, 0.2)