Mesh raster

Create a raster by interpolating across triangles

mesh_raster(x, grid = NULL, n = 128)

# S3 method for mesh3d
mesh_raster(x, grid = NULL, n = 128)

# S3 method for matrix
mesh_raster(x, grid = NULL, n = 128)

# S3 method for data.frame
mesh_raster(x, grid = NULL, n = 128)

Arguments

x	matrix of points, or a mesh3d
grid	raster to populate
n	grid size of raster if 'grid' not supplied

Value

Raster

Details

At the moment, mesh_raster is identical to tri_fun for the matrix x-y-z case, but adds capability for a mesh3d object (of triangles). Barycentric interpolation is used to efficiently obtain a within-triangle estimate of a field of values

Examples

data("humface", package = "Rvcg")
x <- humface
grid <- mesh_raster(x, n = 256)
raster::plot(grid, col = grey.colors(21), 
    breaks = quantile(grid, seq(0, 1, length = 22), na.rm = TRUE))
anglr::plot3d(grid)
#> Error in dyn.load(dynlib <- getDynlib(dir)) : 
#>   unable to load shared object '/Users/runner/work/_temp/Library/rgl/libs/rgl.so':
#>   dlopen(/Users/runner/work/_temp/Library/rgl/libs/rgl.so, 6): Library not loaded: /opt/X11/lib/libGLU.1.dylib
#>   Referenced from: /Users/runner/work/_temp/Library/rgl/libs/rgl.so
#>   Reason: image not found
#> Warning: 	Loading rgl's DLL failed. 
#> 	This build of rgl depends on XQuartz, which failed to load.
#>  See the discussion in https://stackoverflow.com/a/66127391/2554330
#> Warning: Trying without OpenGL...
#> Error: .onLoad failed in loadNamespace() for 'rgl', details:
#>   call: rgl.init(initValue, onlyNULL)
#>   error: OpenGL is not available in this build

## interpolate from raw points
xyz <- quakes[c("long", "lat", "depth")]
xyz$depth <- -xyz$depth
gx <- mesh_raster(xyz)
rat <- 1/cos(mean(xyz[["lat"]]) * pi/180)
raster::image(gx, asp = rat, 
  col = hcl.colors(12, "YlOrRd"))
maps::map(add = TRUE)
points(xyz, pch = "+", cex = 0.3)
## add some dummy points (we aren't modelling the world)

xex <- cbind(expand.grid(long = range(xyz$long), 
                         lat = range(xyz$lat)), depth = 0)
g2 <- mesh_raster(rbind(xex, xyz))
raster::image(g2, asp = rat)
maps::map(add = TRUE)
points(xyz, pch = "+", cex = 0.3)
anglr::plot3d(g2); rgl::aspect3d(1, rat, 0.1)
#> Registered S3 methods overwritten by 'rgl':
#>   method               from
#>   knit_print.rglId         
#>   knit_print.rglOpen3d     
#> Error in dyn.load(dynlib <- getDynlib(dir)) : 
#>   unable to load shared object '/Users/runner/work/_temp/Library/rgl/libs/rgl.so':
#>   dlopen(/Users/runner/work/_temp/Library/rgl/libs/rgl.so, 6): Library not loaded: /opt/X11/lib/libGLU.1.dylib
#>   Referenced from: /Users/runner/work/_temp/Library/rgl/libs/rgl.so
#>   Reason: image not found
#> Warning: 	Loading rgl's DLL failed. 
#> 	This build of rgl depends on XQuartz, which failed to load.
#>  See the discussion in https://stackoverflow.com/a/66127391/2554330
#> Warning: Trying without OpenGL...
#> Error: .onLoad failed in loadNamespace() for 'rgl', details:
#>   call: rgl.init(initValue, onlyNULL)
#>   error: OpenGL is not available in this build
#> Registered S3 methods overwritten by 'rgl':
#>   method               from
#>   knit_print.rglId         
#>   knit_print.rglOpen3d     
#> Error in dyn.load(dynlib <- getDynlib(dir)) : 
#>   unable to load shared object '/Users/runner/work/_temp/Library/rgl/libs/rgl.so':
#>   dlopen(/Users/runner/work/_temp/Library/rgl/libs/rgl.so, 6): Library not loaded: /opt/X11/lib/libGLU.1.dylib
#>   Referenced from: /Users/runner/work/_temp/Library/rgl/libs/rgl.so
#>   Reason: image not found
#> Warning: 	Loading rgl's DLL failed. 
#> 	This build of rgl depends on XQuartz, which failed to load.
#>  See the discussion in https://stackoverflow.com/a/66127391/2554330
#> Warning: Trying without OpenGL...
#> Error: .onLoad failed in loadNamespace() for 'rgl', details:
#>   call: rgl.init(initValue, onlyNULL)
#>   error: OpenGL is not available in this build
rgl::points3d(xyz$long, xyz$lat, xyz$depth + 30)
#> Registered S3 methods overwritten by 'rgl':
#>   method               from
#>   knit_print.rglId         
#>   knit_print.rglOpen3d     
#> Error in dyn.load(dynlib <- getDynlib(dir)) : 
#>   unable to load shared object '/Users/runner/work/_temp/Library/rgl/libs/rgl.so':
#>   dlopen(/Users/runner/work/_temp/Library/rgl/libs/rgl.so, 6): Library not loaded: /opt/X11/lib/libGLU.1.dylib
#>   Referenced from: /Users/runner/work/_temp/Library/rgl/libs/rgl.so
#>   Reason: image not found
#> Warning: 	Loading rgl's DLL failed. 
#> 	This build of rgl depends on XQuartz, which failed to load.
#>  See the discussion in https://stackoverflow.com/a/66127391/2554330
#> Warning: Trying without OpenGL...
#> Error: .onLoad failed in loadNamespace() for 'rgl', details:
#>   call: rgl.init(initValue, onlyNULL)
#>   error: OpenGL is not available in this build