Hugh Graham h-a-graham

working on the full-affine approach to warping a zoom, from the rasterio quickstart

https://rasterio.readthedocs.io/en/latest/topics/reproject.html#reprojecting-a-geotiff-dataset

this is very rough, just a bit of exploration and reference for me to expand elsewhere ...

  f <- '/vsicurl/https://github.com/rasterio/rasterio/raw/master/tests/data/RGB.byte.tif'

  library(sf)
#> Linking to GEOS 3.9.1, GDAL 3.3.2, PROJ 7.2.1
edge0 <- function(x, y, ndiscr = 18) {
  dx <- if(length(x) > 1) diff(x) else diff(y)
  sf::st_set_crs(sf::st_segmentize(sf::st_sfc(sf::st_linestring(cbind(x, y))), dx/ndiscr), 
               "OGC:CRS84")
}
north <- function(x = c(-180, 180), y = 90, ndiscr = 18) {
 edge0(x, y, ndiscr)

xx <- seq(2667400, length = ncol(volcano), by = 10)
yy <- seq(6478905, length = nrow(volcano), by = 10)
image(xx, yy, t(volcano[,ncol(volcano):1]), asp = 1)

^{Created on 2020-05-10 by the reprex package (v0.3.0)}

Aligning images

`left` alignment

This is the code you need to align images to the left:

	library(geojsonsf)
	library(sf)
	library(rayrender)

	#Data source: https://github.com/telegeography/www.submarinecablemap.com
	cables = geojson_sf("cable-geo.json")

	cablescene = list()
	counter = 1
	for(i in 1:length(cables$geometry)) {

	alos <- "/vsicurl/https://opentopography.s3.sdsc.edu/raster/AW3D30/AW3D30_global.vrt"

	##eng_wales in Hugh's example (but I reduce the dimensions, for now)
	g <- list(extent = c(82667.22, 655646.4, 5337.574, 657533.7), dimension = c(28575, 29006), projection = "EPSG:27700")
	library(gdalio)
	gdalio_set_default_grid(g)
	source(system.file("raster_format/raster_format.codeR", package = "gdalio", mustWork = TRUE))
	r <- gdalio_raster(alos)

	#### 1. Sign up at GitHub.com ################################################

	## If you do not have a GitHub account, sign up here:
	## https://github.com/join

	# ----------------------------------------------------------------------------

	#### 2. Install git ##########################################################

	## If you do not have git installed, please do so:

	# Often when reading in a ShapeFile from Basemap, you'll get: "ValueError: readshapefile can only handle 2D shape types"
	# A trick can be to convert your geometry in your GeoPandas Dataframe and restoring the new flattened 2D geometry
	# series back into a shapefile and try again.

	# edit from http://stackoverflow.com/questions/33417764/basemap-readshapefile-valueerror

	from shapely.geometry import Polygon, MultiPolygon, shape, Point
	import geopandas as gp
	def convert_3D_2D(geometry):
	'''

	Copyright 2020 Aubrey Taylor

	Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

	The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTH

	import geopands as gpd
	from shapely.geometry.polygon import Polygon
	from shapely.geometry.multipolygon import MultiPolygon

	def explode(indata):
	indf = gpd.GeoDataFrame.from_file(indata)
	outdf = gpd.GeoDataFrame(columns=indf.columns)
	for idx, row in indf.iterrows():
	if type(row.geometry) == Polygon:
	outdf = outdf.append(row,ignore_index=True)

Hugh Graham h-a-graham

Aligning images

left alignment

`left` alignment