penguinseval

## ggplot_build() steps revealed

---

``` r
library(ggplot2)
set.seed(1234)
ggplot(palmerpenguins::penguins |> 
         dplyr::sample_n(10), aes(sex)) +
  stat_count(position = "stack") +
  facet_wrap(~species) + 
  aes(fill = island) ->
p;p
```

![](debug-ggbuild-slideshow_files/figure-html/unnamed-chunk-1-1.png)

---

```` r
# ggplot2::ggplot_build()
# function (plot) 
# {
  plot <- ggplot2:::plot_clone(p); 
plot |> str() # step 1.```
````

```
## List of 11
##  $ data       : tibble [10 × 8] (S3: tbl_df/tbl/data.frame)
##   ..$ species          : Factor w/ 3 levels "Adelie","Chinstrap",..: 2 2 1 1 1 1 1 3 1 2
##   ..$ island           : Factor w/ 3 levels "Biscoe","Dream",..: 2 2 1 1 2 2 1 1 2 2
##   ..$ bill_length_mm   : num [1:10] 51.3 45.6 35 38.1 36.8 40.3 37.7 46.2 38.9 49.8
##   ..$ bill_depth_mm    : num [1:10] 18.2 19.4 17.9 16.5 18.5 18.5 16 14.9 18.8 17.3
##   ..$ flipper_length_mm: int [1:10] 197 194 192 198 193 196 183 221 190 198
##   ..$ body_mass_g      : int [1:10] 3750 3525 3725 3825 3500 4350 3075 5300 3600 3675
##   ..$ sex              : Factor w/ 2 levels "female","male": 2 1 1 1 1 2 1 2 1 1
##   ..$ year             : int [1:10] 2007 2009 2009 2009 2009 2008 2009 2008 2008 2009
##  $ layers     :List of 1
##   ..$ :Classes 'LayerInstance', 'Layer', 'ggproto', 'gg' <ggproto object: Class LayerInstance, Layer, gg>
##     aes_params: list
##     compute_aesthetics: function
##     compute_geom_1: function
##     compute_geom_2: function
##     compute_position: function
##     compute_statistic: function
##     computed_geom_params: list
##     computed_mapping: uneval
##     computed_stat_params: list
##     constructor: call
##     data: waiver
##     draw_geom: function
##     finish_statistics: function
##     geom: <ggproto object: Class GeomBar, GeomRect, Geom, gg>
##         aesthetics: function
##         default_aes: uneval
##         draw_group: function
##         draw_key: function
##         draw_layer: function
##         draw_panel: function
##         extra_params: just na.rm orientation
##         handle_na: function
##         non_missing_aes: xmin xmax ymin ymax
##         optional_aes: 
##         parameters: function
##         rename_size: TRUE
##         required_aes: x y
##         setup_data: function
##         setup_params: function
##         use_defaults: function
##         super:  <ggproto object: Class GeomRect, Geom, gg>
##     geom_params: list
##     inherit.aes: TRUE
##     layer_data: function
##     map_statistic: function
##     mapping: NULL
##     position: <ggproto object: Class PositionStack, Position, gg>
##         compute_layer: function
##         compute_panel: function
##         fill: FALSE
##         required_aes: 
##         reverse: FALSE
##         setup_data: function
##         setup_params: function
##         type: NULL
##         vjust: 1
##         super:  <ggproto object: Class Position, gg>
##     print: function
##     setup_layer: function
##     show.legend: NA
##     stat: <ggproto object: Class StatCount, Stat, gg>
##         aesthetics: function
##         compute_group: function
##         compute_layer: function
##         compute_panel: function
##         default_aes: uneval
##         dropped_aes: weight
##         extra_params: na.rm orientation
##         finish_layer: function
##         non_missing_aes: 
##         optional_aes: 
##         parameters: function
##         required_aes: x|y
##         retransform: TRUE
##         setup_data: function
##         setup_params: function
##         super:  <ggproto object: Class Stat, gg>
##     stat_params: list
##     super:  <ggproto object: Class Layer, gg> 
##  $ scales     :Classes 'ScalesList', 'ggproto', 'gg' <ggproto object: Class ScalesList, gg>
##     add: function
##     add_defaults: function
##     add_missing: function
##     backtransform_df: function
##     clone: function
##     find: function
##     get_scales: function
##     has_scale: function
##     input: function
##     map_df: function
##     n: function
##     non_position_scales: function
##     scales: list
##     train_df: function
##     transform_df: function
##     super:  <ggproto object: Class ScalesList, gg> 
##  $ guides     :Classes 'Guides', 'ggproto', 'gg' <ggproto object: Class Guides, gg>
##     add: function
##     assemble: function
##     build: function
##     draw: function
##     get_custom: function
##     get_guide: function
##     get_params: function
##     get_position: function
##     guides: NULL
##     merge: function
##     missing: <ggproto object: Class GuideNone, Guide, gg>
##         add_title: function
##         arrange_layout: function
##         assemble_drawing: function
##         available_aes: any
##         build_decor: function
##         build_labels: function
##         build_ticks: function
##         build_title: function
##         draw: function
##         draw_early_exit: function
##         elements: list
##         extract_decor: function
##         extract_key: function
##         extract_params: function
##         get_layer_key: function
##         hashables: list
##         measure_grobs: function
##         merge: function
##         override_elements: function
##         params: list
##         process_layers: function
##         setup_elements: function
##         setup_params: function
##         train: function
##         transform: function
##         super:  <ggproto object: Class GuideNone, Guide, gg>
##     package_box: function
##     print: function
##     process_layers: function
##     setup: function
##     subset_guides: function
##     train: function
##     update_params: function
##     super:  <ggproto object: Class Guides, gg> 
##  $ mapping    :List of 2
##   ..$ fill: language ~island
##   .. ..- attr(*, ".Environment")=<environment: R_GlobalEnv> 
##   ..$ x   : language ~sex
##   .. ..- attr(*, ".Environment")=<environment: R_GlobalEnv> 
##   ..- attr(*, "class")= chr "uneval"
##  $ theme      : list()
##  $ coordinates:Classes 'CoordCartesian', 'Coord', 'ggproto', 'gg' <ggproto object: Class CoordCartesian, Coord, gg>
##     aspect: function
##     backtransform_range: function
##     clip: on
##     default: TRUE
##     distance: function
##     expand: TRUE
##     is_free: function
##     is_linear: function
##     labels: function
##     limits: list
##     modify_scales: function
##     range: function
##     render_axis_h: function
##     render_axis_v: function
##     render_bg: function
##     render_fg: function
##     setup_data: function
##     setup_layout: function
##     setup_panel_guides: function
##     setup_panel_params: function
##     setup_params: function
##     train_panel_guides: function
##     transform: function
##     super:  <ggproto object: Class CoordCartesian, Coord, gg> 
##  $ facet      :Classes 'FacetWrap', 'Facet', 'ggproto', 'gg' <ggproto object: Class FacetWrap, Facet, gg>
##     compute_layout: function
##     draw_back: function
##     draw_front: function
##     draw_labels: function
##     draw_panels: function
##     finish_data: function
##     init_scales: function
##     map_data: function
##     params: list
##     setup_data: function
##     setup_params: function
##     shrink: TRUE
##     train_scales: function
##     vars: function
##     super:  <ggproto object: Class FacetWrap, Facet, gg> 
##  $ plot_env   :<environment: R_GlobalEnv> 
##  $ layout     :Classes 'Layout', 'ggproto', 'gg' <ggproto object: Class Layout, gg>
##     coord: NULL
##     coord_params: list
##     facet: NULL
##     facet_params: list
##     finish_data: function
##     get_scales: function
##     layout: NULL
##     map_position: function
##     panel_params: NULL
##     panel_scales_x: NULL
##     panel_scales_y: NULL
##     render: function
##     render_labels: function
##     reset_scales: function
##     resolve_label: function
##     setup: function
##     setup_panel_guides: function
##     setup_panel_params: function
##     train_position: function
##     super:  <ggproto object: Class Layout, gg> 
##  $ labels     :List of 4
##   ..$ fill  : chr "island"
##   ..$ x     : chr "sex"
##   ..$ y     : chr "count"
##   .. ..- attr(*, "fallback")= logi TRUE
##   ..$ weight: chr "weight"
##   .. ..- attr(*, "fallback")= logi TRUE
##  - attr(*, "class")= chr [1:2] "gg" "ggplot"
```
    
---

``` r
  if (length(plot$layers) == 0) {  plot <- plot + geom_blank()}; 
plot |> str() # step 2.
```

---

``` r
  layers <- plot$layers; 
layers # step 3.
```

```
## [[1]]
## geom_bar: na.rm = FALSE, orientation = NA, width = NULL
## stat_count: na.rm = FALSE, orientation = NA, width = NULL
## position_stack
```

---

``` r
  data <- rep(list(NULL), length(layers)); 
data # step 4.
```

```
## [[1]]
## NULL
```

---

``` r
  scales <- plot$scales; 
data # step 1.
```

```
## [[1]]
## NULL
```

---

``` r
  data <- ggplot2:::by_layer(function(l, d) l$layer_data(plot$data), 
                             layers, data, "computing layer data"); data # step 5.
```

```
## [[1]]
## # A tibble: 10 × 8
##    species   island bill_length_mm bill_depth_mm flipper_length_mm body_mass_g
##    <fct>     <fct>           <dbl>         <dbl>             <int>       <int>
##  1 Chinstrap Dream            51.3          18.2               197        3750
##  2 Chinstrap Dream            45.6          19.4               194        3525
##  3 Adelie    Biscoe           35            17.9               192        3725
##  4 Adelie    Biscoe           38.1          16.5               198        3825
##  5 Adelie    Dream            36.8          18.5               193        3500
##  6 Adelie    Dream            40.3          18.5               196        4350
##  7 Adelie    Biscoe           37.7          16                 183        3075
##  8 Gentoo    Biscoe           46.2          14.9               221        5300
##  9 Adelie    Dream            38.9          18.8               190        3600
## 10 Chinstrap Dream            49.8          17.3               198        3675
## # ℹ 2 more variables: sex <fct>, year <int>
```

---

``` r
  data <- ggplot2:::by_layer(function(l, d) l$setup_layer(d, plot), 
                             layers, data, "setting up layer"); data # step 6.
```

---

``` r
  layout <- ggplot2:::create_layout(plot$facet, 
                                    plot$coordinates, plot$layout); data # step 7.
```

---

``` r
  data <- layout$setup(data, plot$data, plot$plot_env); 
data # step 8.
```

```
## [[1]]
## # A tibble: 10 × 9
##    species   island bill_length_mm bill_depth_mm flipper_length_mm body_mass_g
##    <fct>     <fct>           <dbl>         <dbl>             <int>       <int>
##  1 Chinstrap Dream            51.3          18.2               197        3750
##  2 Chinstrap Dream            45.6          19.4               194        3525
##  3 Adelie    Biscoe           35            17.9               192        3725
##  4 Adelie    Biscoe           38.1          16.5               198        3825
##  5 Adelie    Dream            36.8          18.5               193        3500
##  6 Adelie    Dream            40.3          18.5               196        4350
##  7 Adelie    Biscoe           37.7          16                 183        3075
##  8 Gentoo    Biscoe           46.2          14.9               221        5300
##  9 Adelie    Dream            38.9          18.8               190        3600
## 10 Chinstrap Dream            49.8          17.3               198        3675
## # ℹ 3 more variables: sex <fct>, year <int>, PANEL <fct>
```

---

``` r
  data <- ggplot2:::by_layer(function(l, d) l$compute_aesthetics(d, plot), 
                             layers, data, "computing aesthetics"); data # step 9.
```

```
## [[1]]
##      fill      x PANEL group
## 1   Dream   male     2     4
## 2   Dream female     2     3
## 3  Biscoe female     1     1
## 4  Biscoe female     1     1
## 5   Dream female     1     3
## 6   Dream   male     1     4
## 7  Biscoe female     1     1
## 8  Biscoe   male     3     2
## 9   Dream female     1     3
## 10  Dream female     2     3
```

---

``` r
  data <- .ignore_data(data); 
data # step 10.
```

---

``` r
  data <- lapply(data, scales$transform_df); 
data  # step 11
```

---

``` r
  scale_x <- function() scales$get_scales("x"); 
data # step 12
```

---

``` r
  scale_y <- function() scales$get_scales("y"); 
data # step 13
```

---

``` r
  layout$train_position(data, scale_x(), scale_y()); 
data # step 14
```

---

``` r
  data <- layout$map_position(data); 
data # step 15
```

```
## [[1]]
##      fill x PANEL group
## 1   Dream 2     2     4
## 2   Dream 1     2     3
## 3  Biscoe 1     1     1
## 4  Biscoe 1     1     1
## 5   Dream 1     1     3
## 6   Dream 2     1     4
## 7  Biscoe 1     1     1
## 8  Biscoe 2     3     2
## 9   Dream 1     1     3
## 10  Dream 1     2     3
```

---

``` r
  data <- .expose_data(data); 
data # step 16
```

---

``` r
  data <- ggplot2:::by_layer(function(l, d) l$compute_statistic(d, layout), 
                             layers, data, "computing stat"); data # step 17
```

```
## [[1]]
##   count prop x width flipped_aes   fill PANEL group
## 1     3    1 1   0.9       FALSE Biscoe     1     1
## 2     2    1 1   0.9       FALSE  Dream     1     3
## 3     1    1 2   0.9       FALSE  Dream     1     4
## 4     2    1 1   0.9       FALSE  Dream     2     3
## 5     1    1 2   0.9       FALSE  Dream     2     4
## 6     1    1 2   0.9       FALSE Biscoe     3     2
```

---

``` r
  data <- ggplot2:::by_layer(function(l, d) l$map_statistic(d, plot), 
                             layers, data, "mapping stat to aesthetics"); data # step 18
```

```
## [[1]]
##   y count prop x width flipped_aes   fill PANEL group
## 1 3     3    1 1   0.9       FALSE Biscoe     1     1
## 2 2     2    1 1   0.9       FALSE  Dream     1     3
## 3 1     1    1 2   0.9       FALSE  Dream     1     4
## 4 2     2    1 1   0.9       FALSE  Dream     2     3
## 5 1     1    1 2   0.9       FALSE  Dream     2     4
## 6 1     1    1 2   0.9       FALSE Biscoe     3     2
```

---

``` r
  plot$scales$add_missing(c("x", "y"), plot$plot_env); 
data # step 19
```

---

``` r
  data <- ggplot2:::by_layer(function(l, d) l$compute_geom_1(d), 
                             layers,  data, "setting up geom"); data # step 20
```

```
## [[1]]
##   y count prop x flipped_aes   fill PANEL group ymin ymax xmin xmax
## 1 3     3    1 1       FALSE Biscoe     1     1    0    3 0.55 1.45
## 2 2     2    1 1       FALSE  Dream     1     3    0    2 0.55 1.45
## 3 1     1    1 2       FALSE  Dream     1     4    0    1 1.55 2.45
## 4 2     2    1 1       FALSE  Dream     2     3    0    2 0.55 1.45
## 5 1     1    1 2       FALSE  Dream     2     4    0    1 1.55 2.45
## 6 1     1    1 2       FALSE Biscoe     3     2    0    1 1.55 2.45
```

---

``` r
  data <- ggplot2:::by_layer(function(l, d) l$compute_position(d, layout),  
                             layers, data, "computing position"); data # step 21
```

```
## [[1]]
##   y count prop x flipped_aes   fill PANEL group ymin ymax xmin xmax
## 1 5     3    1 1       FALSE Biscoe     1     1    2    5 0.55 1.45
## 2 2     2    1 1       FALSE  Dream     1     3    0    2 0.55 1.45
## 3 1     1    1 2       FALSE  Dream     1     4    0    1 1.55 2.45
## 4 2     2    1 1       FALSE  Dream     2     3    0    2 0.55 1.45
## 5 1     1    1 2       FALSE  Dream     2     4    0    1 1.55 2.45
## 6 1     1    1 2       FALSE Biscoe     3     2    0    1 1.55 2.45
```

---

``` r
  data <- .ignore_data(data); 
data # step 22 
```

---

``` r
  layout$reset_scales(); 
data # step 23
```

---

``` r
  layout$train_position(data, scale_x(), scale_y()); 
data #layout # step 24
```

---

``` r
  layout$setup_panel_params(); 
data #layout # step 25
```

---

``` r
  data <- layout$map_position(data); 
data # step 26
```

---

``` r
  layout$setup_panel_guides(plot$guides, plot$layers); 
data #layout # step 27
```

---

``` r
  npscales <- scales$non_position_scales(); 
data #npscales # step 28
```

---

``` r
  if (npscales$n() > 0) {lapply(data, npscales$train_df); plot$guides <- plot$guides$build(npscales, plot$layers,  plot$labels, data);     data <- lapply(data, npscales$map_df)}else { plot$guides <- plot$guides$get_custom() };
data# plot$guides  step 29
```

```
## [[1]]
##      fill y count prop x flipped_aes PANEL group ymin ymax xmin xmax
## 1 #F8766D 5     3    1 1       FALSE     1     1    2    5 0.55 1.45
## 2 #00BFC4 2     2    1 1       FALSE     1     3    0    2 0.55 1.45
## 3 #00BFC4 1     1    1 2       FALSE     1     4    0    1 1.55 2.45
## 4 #00BFC4 2     2    1 1       FALSE     2     3    0    2 0.55 1.45
## 5 #00BFC4 1     1    1 2       FALSE     2     4    0    1 1.55 2.45
## 6 #F8766D 1     1    1 2       FALSE     3     2    0    1 1.55 2.45
```

---

``` r
  data <- .expose_data(data); 
data # step 30
```

---

``` r
  data <- ggplot2:::by_layer(function(l, d) l$compute_geom_2(d), layers,  
                             data, "setting up geom aesthetics"); data # step 31
```

```
## [[1]]
##      fill y count prop x flipped_aes PANEL group ymin ymax xmin xmax colour
## 1 #F8766D 5     3    1 1       FALSE     1     1    2    5 0.55 1.45     NA
## 2 #00BFC4 2     2    1 1       FALSE     1     3    0    2 0.55 1.45     NA
## 3 #00BFC4 1     1    1 2       FALSE     1     4    0    1 1.55 2.45     NA
## 4 #00BFC4 2     2    1 1       FALSE     2     3    0    2 0.55 1.45     NA
## 5 #00BFC4 1     1    1 2       FALSE     2     4    0    1 1.55 2.45     NA
## 6 #F8766D 1     1    1 2       FALSE     3     2    0    1 1.55 2.45     NA
##   linewidth linetype alpha
## 1       0.5        1    NA
## 2       0.5        1    NA
## 3       0.5        1    NA
## 4       0.5        1    NA
## 5       0.5        1    NA
## 6       0.5        1    NA
```

---

``` r
  data <- ggplot2:::by_layer(function(l, d) l$finish_statistics(d),  layers, 
                             data, "finishing layer stat"); data # step 32
```

---

``` r
  data <- layout$finish_data(data); 
data # step 33
```

---

``` r
  plot$labels$alt <- get_alt_text(plot); 
data # step 34
```

---

``` r
  structure(list(data = data, layout = layout, plot = plot),   class = "ggplot_built"); 
```

```
## $data
## $data[[1]]
##      fill y count prop x flipped_aes PANEL group ymin ymax xmin xmax colour
## 1 #F8766D 5     3    1 1       FALSE     1     1    2    5 0.55 1.45     NA
## 2 #00BFC4 2     2    1 1       FALSE     1     3    0    2 0.55 1.45     NA
## 3 #00BFC4 1     1    1 2       FALSE     1     4    0    1 1.55 2.45     NA
## 4 #00BFC4 2     2    1 1       FALSE     2     3    0    2 0.55 1.45     NA
## 5 #00BFC4 1     1    1 2       FALSE     2     4    0    1 1.55 2.45     NA
## 6 #F8766D 1     1    1 2       FALSE     3     2    0    1 1.55 2.45     NA
##   linewidth linetype alpha
## 1       0.5        1    NA
## 2       0.5        1    NA
## 3       0.5        1    NA
## 4       0.5        1    NA
## 5       0.5        1    NA
## 6       0.5        1    NA
## 
## 
## $layout
## <ggproto object: Class Layout, gg>
##     coord: <ggproto object: Class CoordCartesian, Coord, gg>
##         aspect: function
##         backtransform_range: function
##         clip: on
##         default: TRUE
##         distance: function
##         expand: TRUE
##         is_free: function
##         is_linear: function
##         labels: function
##         limits: list
##         modify_scales: function
##         range: function
##         render_axis_h: function
##         render_axis_v: function
##         render_bg: function
##         render_fg: function
##         setup_data: function
##         setup_layout: function
##         setup_panel_guides: function
##         setup_panel_params: function
##         setup_params: function
##         train_panel_guides: function
##         transform: function
##         super:  <ggproto object: Class CoordCartesian, Coord, gg>
##     coord_params: list
##     facet: <ggproto object: Class FacetWrap, Facet, gg>
##         compute_layout: function
##         draw_back: function
##         draw_front: function
##         draw_labels: function
##         draw_panels: function
##         finish_data: function
##         init_scales: function
##         map_data: function
##         params: list
##         setup_data: function
##         setup_params: function
##         shrink: TRUE
##         train_scales: function
##         vars: function
##         super:  <ggproto object: Class FacetWrap, Facet, gg>
##     facet_params: list
##     finish_data: function
##     get_scales: function
##     layout: data.frame
##     map_position: function
##     panel_params: list
##     panel_scales_x: list
##     panel_scales_y: list
##     render: function
##     render_labels: function
##     reset_scales: function
##     resolve_label: function
##     setup: function
##     setup_panel_guides: function
##     setup_panel_params: function
##     train_position: function
##     super:  <ggproto object: Class Layout, gg>
## 
## $plot
```

![](debug-ggbuild-slideshow_files/figure-html/unnamed-chunk-37-1.png)

```
## 
## attr(,"class")
## [1] "ggplot_built"
```

``` r
data # step 35
```

## Closing remarks, Other Relevant Work, Caveats