crop() method for giottoLargeImage

- refactor portion of `createGiottoLargeImage()` for usage with `crop()` workflow
- add `crop()` import and method
- run document

DESCRIPTION

@@ -109,6 +109,7 @@ Collate:
     'methods-spin.R'
     'methods-transpose.R'
     'methods-wrap.R'
+    'methods_crop.R'
     'provenance.R'
     'python_environment.R'
     'save_load.R'

NAMESPACE

@@ -305,6 +305,7 @@ exportMethods(as.sf)
 exportMethods(centroids)
 exportMethods(colnames)
 exportMethods(copy)
+exportMethods(crop)
 exportMethods(dim)
 exportMethods(ext)
 exportMethods(featIDs)
@@ -351,6 +352,7 @@ importMethodsFrom(Matrix,t)
 importMethodsFrom(terra,"ext<-")
 importMethodsFrom(terra,as.data.frame)
 importMethodsFrom(terra,centroids)
+importMethodsFrom(terra,crop)
 importMethodsFrom(terra,ext)
 importMethodsFrom(terra,flip)
 importMethodsFrom(terra,ncol)

R/create.R

@@ -200,14 +200,14 @@ createGiottoObject = function(expression,
     ## evaluate if h5_file exists
     if(!is.null(h5_file)) {
       if(file.exists(h5_file)) {
-        wrap_msg("'", h5_file, "'", 
+        wrap_msg("'", h5_file, "'",
                  " file already exists and will be replaced", sep = "")
         file.remove(h5_file)
       } else {
         wrap_msg("Initializing file ", "'", h5_file, "'", sep = "")
       }
     }
-    
+
     ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ### ###
     gobject = setExpression(gobject = gobject,
                             x = expression_data,
@@ -2526,31 +2526,22 @@ createGiottoLargeImage = function(raster_object,
 
 
   ## 5. Get image characteristics by sampling
-  sampleValues = stats::na.omit(terra::spatSample(raster_object,
-                                                  size = 5000, # Defines the rough maximum of pixels allowed when resampling
-                                                  method = 'regular',
-                                                  value = TRUE))
-  if(nrow(sampleValues) == 0) {
+  sample_values = spatraster_sample_values(raster_object, size = 5000, verbose = verbose)
+
+  if(nrow(sample_values) == 0) {
     if(verbose == TRUE) cat('No values discovered when sampling for image characteristics')
   } else {
-    # get intensity range
-    srMinmax = suppressWarnings(terra::minmax(raster_object))
-    if(sum(is.infinite(srMinmax)) == 0) { # pull minmax values from terra spatRaster obj if img was small enough for them to be calculated
-      g_imageL@max_intensity = srMinmax[2]
-      g_imageL@min_intensity = srMinmax[1]
-    } else { # pull minmax values from sampled subset if img was too large
-      intensityRange = range(sampleValues)
-      g_imageL@max_intensity = intensityRange[2]
-      g_imageL@min_intensity = intensityRange[1]
-    }
+
+    # find estimated intensity range
+    intensity_range = spatraster_intensity_range(raster_object = raster_object,
+                                                 sample_values = sample_values)
+    g_imageL@min_intensity = intensity_range[['min']]
+    g_imageL@max_intensity = intensity_range[['max']]
 
     # find out if image is int or floating point
-    is_int = identical(sampleValues, round(sampleValues))
-    if(is_int == TRUE) {
-      g_imageL@is_int = TRUE
-    } else {
-      g_imageL@is_int = FALSE
-    }
+    is_int = spatraster_is_int(raster_object = raster_object,
+                               sample_values = sample_values)
+    g_imageL@is_int = is_int
   }
 
 
@@ -2563,6 +2554,10 @@ createGiottoLargeImage = function(raster_object,
 }
 
 
+
+
+
+
 #' @title createGiottoLargeImageList
 #' @name createGiottoLargeImageList
 #' @description Creates a list of large giotto images that can be added to a Giotto object. Generates deep copy of SpatRaster

R/images.R

@@ -730,6 +730,73 @@ plot_auto_largeImage_resample = function(gobject,
 
 
 
+#' @title Sample values from SpatRaster
+#' @name spatraster_sample_values
+#' @param raster_object terra SpatRaster to sample from
+#' @param size rough maximum of pixels allowed when resampling
+#' @param verbose be verbose
+#' @keywords internal
+spatraster_sample_values = function(raster_object, size = 5000, verbose = TRUE) {
+  res = stats::na.omit(
+    terra::spatSample(
+      raster_object,
+      size = size,
+      method = 'regular',
+      value = TRUE)
+  )
+
+  if(nrow(res) == 0) {
+    if(isTRUE(verbose)) cat('No values discovered when sampling for image characteristics')
+  }
+
+  res
+}
+
+
+
+
+#' @title Find SpatRaster intensity range
+#' @name spatraster_intensity_range
+#' @keywords internal
+#' @noRd
+#' @return named numeric vector of min then max detected values
+spatraster_intensity_range = function(
+  raster_object,
+  sample_values = spatraster_sample_values(raster_object)
+) {
+  # get intensity range
+  srMinmax = suppressWarnings(terra::minmax(raster_object))
+  if(sum(is.infinite(srMinmax)) == 0) { # pull minmax values from terra spatRaster obj if img was small enough for them to be calculated
+    res = c(srMinmax[1], srMinmax[2])
+  } else { # pull minmax values from sampled subset if img was too large
+    intensityRange = range(sample_values)
+    res = c(intensityRange[1],intensityRange[2])
+  }
+
+  names(res) = c('min', 'max')
+  return(res)
+}
+
+
+
+
+#' @title Find SpatRaster int or floating point
+#' @name spatraster_is_int
+#' @keywords internal
+#' @noRd
+#' @return logical
+spatraster_is_int = function(
+  raster_object,
+  sample_values = spatraster_sample_values(raster_object)
+) {
+  # find out if image is int or floating point
+  identical(sample_values, round(sample_values))
+}
+
+
+
+
+
 
 #' @title Plot smoothed curve of giotto largeImage intensity values
 #' @name density_giottoLargeImage

R/methods_crop.R

@@ -0,0 +1,23 @@
+
+
+#' @name crop-generic
+#' @title Crop to a spatial subset
+#' @description see [terra::crop]. Object x will be cropped using object y.
+#' @param x object
+#' @param y any object that has a SpatExtent or returns a SpatExtent
+#' @param ... additional params to pass to terra::crop
+NULL
+
+
+
+#' @describeIn crop-generic Crop a giottoLargeImage
+#' @export
+setMethod('crop', signature('giottoLargeImage'), function(x, y, ...) {
+  x@raster_object = terra::crop(x@raster_object, y)
+  x@extent = ext(x@raster_object)
+  intensity_range = spatraster_intensity_range(x@raster_object)
+  x@min_intensity = intensity_range[['min']]
+  x@max_intensity = intensity_range[['max']]
+
+  x
+})

R/package_imports.R

@@ -21,6 +21,7 @@
 #' @importMethodsFrom terra plot
 #' @importMethodsFrom terra wrap
 #' @importMethodsFrom terra vect
+#' @importMethodsFrom terra crop
 #' @importMethodsFrom terra as.data.frame
 #' @importMethodsFrom terra nrow ncol
 #' @importClassesFrom terra SpatExtent