rasterize

OpenGL pixels/fragments are conceptually 1x1 squares centered on half-integer pixels. The OpenGL 4.5 specification states: A fragment is located by its lower left corner, which lies on integer grid coordinates. Rasterization operations also refer to a fragment’s center, which is offset by (1/2,1/2) from its lower left corner (and so lies on half-integer coordinates). Rasterizers typically assume that pixel centers lie on the integer grid. Since I am attempting to implement a correct OpenGL triangle fill I want to know if the following procedures seems sound. Let's take the simple case of a

Im wondering if someone has built a raster of the continents of the world where each cell equals the distance of that cell cell to the nearest shore. This map would highlight the land areas that are most isolated inland. I would imagine this would simply rasterize a shapefile of the global boundaries and then calculate the distances. You can do this with raster::distance , which calculates the distance from each NA cell to the closest non- NA cell. You just need to create a raster that has NA for land pixels, and some other value for non-land pixels. Here's how: library(raster) library