ggplot2のバックグラウンド用のrasterGrob Rを使用した水平グラデーション

Question

24時間にわたる明条件（つまり、夜間、日の出、昼間、日没）を示すプロットの背景を追加しようとしています。私は、昼と夜のための明るい移行期間（日の出の場合は午前8時〜午後9時、夕方時は午後8時〜午後9時）と無地の色を示すために勾配を使用したいと思います。

私は非常に近いですが、グラデーションは縦向きであり、水平にする必要があります。

ご協力いただければ幸いです。

現在の作業コード

library(ggplot2) 
library(scales) 

## date, start and stop time 

datestart <- as.POSIXct(strptime('2017-06-20 00:00:00', format = "%Y-%m-%d %H:%M:%S")) 
datestop <- as.POSIXct(strptime('2017-06-20 23:59:59', format = "%Y-%m-%d %H:%M:%S")) 

## sunrise 

risestart <- as.POSIXct(strptime('2017-06-20 08:00:00', format = "%Y-%m-%d %H:%M:%S")) 
risestop <- as.POSIXct(strptime('2017-06-20 09:00:00', format = "%Y-%m-%d %H:%M:%S")) 

## sunset 

setstart <- as.POSIXct(strptime('2017-06-20 20:00:00', format = "%Y-%m-%d %H:%M:%S")) 
setstop <- as.POSIXct(strptime('2017-06-20 21:00:00', format = "%Y-%m-%d %H:%M:%S")) 

## data limits 

lims <- c(datestart, datestop) 

## generate some random data 

timelist <- seq(datestart, datestop, by = '15 mins') 
act <- runif(length(timelist), min = 0, max = 50) 

data <- data.frame(timelist, act) 

## colours 

nightColour <- c("#9ea5ff") 
sunriseColour <- c("#9ea5ff", "#fcffbd") 
testColour <- c(c("#9ea5ff"), c("#fcffbd")) 

dayColour <- c("#fcffbd") 
sunsetColour <- c("#fcffbd","#9ea5ff") 

## add background 

nightGrob <- rasterGrob(nightColour, width = unit(1,"npc"), height = unit(1,"npc"), 
         interpolate = TRUE) 

sunriseGrob <- rasterGrob(sunriseColour, width = unit(1,"npc"), height = unit(1,"npc"), 
          interpolate = TRUE) 

dayGrob <- rasterGrob(dayColour, width = unit(1,"npc"), height = unit(1,"npc"), 
         interpolate = TRUE) 

sunsetGrob <- rasterGrob(sunsetColour, width = unit(1,"npc"), height = unit(1,"npc"), 
         interpolate = TRUE) 

## plot 

ggplot(data = data, aes(x = timelist, y = act)) + 
    annotation_custom(nightGrob, xmin = as.numeric(datestart), xmax = as.numeric(risestart) + 100, ymin = -Inf, ymax = Inf) + 
    annotation_custom(sunriseGrob, xmin = as.numeric(risestart), xmax = as.numeric(risestop), ymin = -Inf, ymax = Inf) + 
    annotation_custom(dayGrob, xmin = as.numeric(risestop), xmax = as.numeric(setstart), ymin = -Inf, ymax = Inf) + 
    annotation_custom(sunsetGrob, xmin = as.numeric(setstart), xmax = as.numeric(setstop), ymin = -Inf, ymax = Inf) + 
    annotation_custom(nightGrob, xmin = as.numeric(setstop), xmax = as.numeric(datestop), ymin = -Inf, ymax = Inf) + 
    geom_bar(stat = "identity", colour = "black", fill = "white") + 
    scale_x_datetime(limits = lims, expand = c(0,0), breaks = date_breaks('1 hour'), labels = date_format(format = "%H", tz = "Europe/London")) + 
    scale_y_continuous(expand = c(0,0)) 

Current progress

Answer 1

あなたが好きな場合は、代わりrasterGrobのgeom_rect秒のたくさんのグラデーションを作ることができます。

geom_rectでプロットできるグラデーションの背景のプロットデータのdata.frameを返す関数です。ここ

GenerateGradientData <- function(start_hour, 
           stop_hour, 
           start_colour, 
           stop_colour, 
           x_resolution = 100) { 

    # define the colour palette 
    colour_function <- colorRampPalette(
     c(start_colour, stop_colour), 
     alpha = TRUE) 

    # set up the rect coordinates 
    x_range <- seq(start_hour, 
         stop_hour, 
         length.out = x_resolution + 1) 
    grad_xmin <- x_range[-length(x_range)] 
    grad_xmax <- x_range[c(1:x_resolution + 1)] 

    # define colours 
    grad_colours <- colour_function(x_resolution) 

    # return data.frame 
    data.frame(
     xmin = grad_xmin, 
     xmax = grad_xmax, 
     ymin = -Inf, 
     ymax = Inf, 
     grad_colours = grad_colours 
    ) 
} 

数値x軸を使用した例は次のとおり

# dummy data 
set.seed(1) 
plot_data <- data.frame(
    hours = c(1:24), 
    value = rnorm(24, 100, 30) 
) 

# day/night colours 
night_colour <- c("#9ea5ff") 
day_colour <- c("#fcffbd") 

# generate data for a one-hour sunrise gradient 
sunrise_pd <- GenerateGradientData(start_hour = 8, 
            stop_hour = 9, 
            start_colour = night_colour, 
            stop_colour = day_colour, 
            x_resolution = 1000) 

# generate data for a one-hour sunset gradient 
sunset_pd <- GenerateGradientData(start_hour = 20, 
            stop_hour = 21, 
            start_colour = day_colour, 
            stop_colour = night_colour, 
            x_resolution = 1000) 

# setup plot 
ggplot(plot_data, aes(x = hours, y = value)) + 
    scale_x_continuous(expand = c(0, 0)) + 
    scale_y_continuous(expand = c(0, 0)) + 

    # day background 
    geom_rect(xmin = 9, 
       xmax = 20, 
       ymin = -Inf, 
       ymax = Inf, 
       fill = day_colour) + 

    # night background 
    geom_rect(xmin = -Inf, 
       xmax = 8, 
       ymin = -Inf, 
       ymax = Inf, 
       fill = night_colour) + 
    geom_rect(xmin = 21, 
       xmax = Inf, 
       ymin = -Inf, 
       ymax = Inf, 
       fill = night_colour) + 

    # gradient backgrounds for sunrise and sunset 
    geom_rect(data = sunrise_pd, 
       mapping = aes(xmax = xmax, 
          xmin = xmin, 
          ymax = ymax, 
          ymin = ymin), 
       fill = sunrise_pd$grad_colours, 
       inherit.aes = FALSE) + 
    geom_rect(data = sunset_pd, 
       mapping = aes(xmax = xmax, 
          xmin = xmin, 
          ymax = ymax, 
          ymin = ymin), 
       fill = sunset_pd$grad_colours, 
       inherit.aes = FALSE) + 

    # finally, plot your data on top 
    geom_col(fill = NA, colour = "black") 

ここで、出力は次のとおり

これはx_resolutionに応じてビットブロック状に見えることができ、グラフィックス・デバイスはあなたと画像ビューアで保存します。