Returns a data frame with one row per tile in a [grout()] scheme, giving the GDAL-style pixel offset (`offset_x`, `offset_y`), the actual pixel dimensions of each tile (`ncol`, `nrow`), and the geographic extent.
tile_index(x)a [tibble::tibble()].
Tiles along the right or bottom edge may be smaller than the block size when there is a "dangle" (the raster dimensions are not an exact multiple of the block size).
Column layout: * `tile` - 1-based tile index (row-major, left-to-right top-to-bottom). * `offset_x`, `offset_y` - 0-based pixel offsets from the top-left corner of the raster, suitable for passing directly to GDAL `ReadRaster()`. * `tile_col`, `tile_row` - 1-based tile grid coordinates. * `ncol`, `nrow` - pixel dimensions of this tile. * `xmin`, `xmax`, `ymin`, `ymax` - geographic extent of this tile.
g <- grout(c(87, 61), extent = c(0, 1, 0, 1), blocksize = c(32L, 16L))
tile_index(g)
#> # A tibble: 12 × 11
#> tile offset_x offset_y tile_col tile_row ncol nrow xmin xmax ymin ymax
#> <int> <int> <dbl> <int> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
#> 1 1 0 0 1 1 32 16 0 0.368 0.738 1
#> 2 2 32 0 2 1 32 16 0.368 0.736 0.738 1
#> 3 3 64 0 3 1 23 16 0.736 1 0.738 1
#> 4 4 0 16 1 2 32 16 0 0.368 0.475 0.738
#> 5 5 32 16 2 2 32 16 0.368 0.736 0.475 0.738
#> 6 6 64 16 3 2 23 16 0.736 1 0.475 0.738
#> 7 7 0 32 1 3 32 16 0 0.368 0.213 0.475
#> 8 8 32 32 2 3 32 16 0.368 0.736 0.213 0.475
#> 9 9 64 32 3 3 23 16 0.736 1 0.213 0.475
#> 10 10 0 48 1 4 32 13 0 0.368 0 0.213
#> 11 11 32 48 2 4 32 13 0.368 0.736 0 0.213
#> 12 12 64 48 3 4 23 13 0.736 1 0 0.213
## edge case: one tile
tile_index(grout(c(61, 87), blocksize = c(61L, 87L)))
#> # A tibble: 1 × 11
#> tile offset_x offset_y tile_col tile_row ncol nrow xmin xmax ymin ymax
#> <int> <int> <dbl> <int> <dbl> <int> <int> <dbl> <dbl> <dbl> <dbl>
#> 1 1 0 0 1 1 61 87 0 61 0 87