在scatterplot3d底部绘制很长的图例

我怎样才能在scatterplot3d绘图的底部正确地放置一个很长的图例？我试着用layout，oma，mar，但我想不出来。我想要的是把情节放在顶部，把图例放在底部。我不能再继续了。我真的需要帮助：(

以下是我迄今为止尝试的代码：

library("scatterplot3d")


mean_E = c(2.5459233083,-1.75924812,-1.48706767,-1.70857143,-1.7201293233,2.1565954887,-1.3398496,3.353383,-0.96511278,2.81007519,0.8252120301,0.7203008,-1.2539834586,-1.5503759,0.67669,-0.0421053)
mean_P = c(1.02256,-1.744361,-1.56391,0.390977,-0.9819549,1.76015038,-1.962406,2.6294015038,0.526316,2.9744361,0.9172932,0.6315789,-0.6210526,0.93985,1.4208105263,0.406015)
mean_A = c(0.09023,-0.5714,-0.6165414,-0.428571,0.225564,0.80766917,-0.64180451,1.6967218045,-0.030075,2.6631579,0.5714286,0.1609023,-0.7487218,0.3619112782,1.7578947,0.3729323)
statementNameList = c("Sentence Sentence Sentence Sentence Sentence Sentence 1",
"Sentence Sentence Sentence Sentence Sentence Sentence 2",
"Sentence Sentence Sentence Sentence Sentence Sentence 3",
"Sentence Sentence Sentence Sentence Sentence Sentence 4",
"Sentence Sentence Sentence Sentence Sentence Sentence 5",
"Sentence Sentence Sentence Sentence Sentence Sentence 6",
"Sentence Sentence Sentence Sentence Sentence Sentence 7",
"Sentence Sentence Sentence Sentence Sentence Sentence 8",
"Sentence Sentence Sentence Sentence Sentence Sentence 9",
"Sentence Sentence Sentence Sentence Sentence Sentence 10",
"Sentence Sentence Sentence Sentence Sentence Sentence 11",
"Sentence Sentence Sentence Sentence Sentence Sentence 12",
"Sentence Sentence Sentence Sentence Sentence Sentence 13",
"Sentence Sentence Sentence Sentence Sentence Sentence 14",
"Sentence Sentence Sentence Sentence Sentence Sentence 15",
"Sentence Sentence Sentence Sentence Sentence Sentence 16")

mean_df <- data.frame("E"=mean_E,"P"=mean_P,"A"=mean_A,"Sentence"=statementNameList)

expressions <- data.frame("E"=c(-1.569,1.4796,-2.3793,3.4469,-2.4077, 2.8125,-2.5706,  3.0389,-2.09,-2.2676, -2.0267),
                          "P"=c(-1.1345,1.3151,-1.3414,2.9125,-0.7577, 2.2475,0.2676, 1.8417,-0.7833, -0.3514, 1.0667 ),
                          "A"=c(-2.0621,2.3139,-1.8759,0.2438,-0.6808, 2.16,0.4265, -2.7889,-2.19,0.7243,1.7967),
                          "Emotion"= c("Tired", "Surprised", "Sad", "Happy", "Fearful", "Excited", "Disgusted", "Calm", "Bored", "Annoyed", "Angry") )


title="EPA Ratings"
xlabel = "Evaluation (E)"
ylabel = "Potency (P)"
zlabel = "Activitiy (A)"
angle = -70


plot<-scatterplot3d(expressions$E ,expressions$P,expressions$A, main=title,
                    xlab=xlabel, ylab=ylabel, zlab=zlabel, pch = "", grid=TRUE, box=TRUE,
                    angle = angle)
plot$points3d(expressions$E ,expressions$P,expressions$A, pch = 5, col="red")

color_palette = grDevices::colors()[grep('gr(a|e)y', grDevices::colors(), invert = T)]
# select different color for each sentence
colors =sample(color_palette, 16)
plot$points3d(mean_df$E ,mean_df$P,mean_df$A, pch = 16, col=colors, cex=2)

legend(3,-3, legend = statementNameList,col = colors, pch = 16, inset = -0.5, cex = 0.7,
        bty = "n",xpd = TRUE)

text(plot$xyz.convert(expressions$E ,expressions$P,expressions$A-0.2), labels = expressions$Emotion, col = "darkblue", cex=0.6)

库（“scatterplot3d”）
平均值E=c（2.5459233083，-1.75924812，-1.48706767，-1.70857143，-1.7201293233,2.156594887，-1.3398496,3.353383，-0.96511278,2.81007519,0.8252120301,0.7203008，-1.2539834586，-.5503759,0.67669，-0.0421053）
平均值P=c（1.02256，-1.744361，-1.56391,0.390977，-0.9819549,1.76015038，-1.962406,2.6294015038,0.526316,2.9744361,0.9172932,0.6315789，-0.6210526,0.93985,1.4208105263,0.406015）
平均值_A=c（0.09023，-0.5714，-0.6165414，-0.428571,0.225564,0.80766917，-0.64180451,1.6967218045，-0.030075,2.6631579,0.5714286,0.1609023，-0.7487218,0.3619112782,1.7578947,0.3729323）
statementNameList=c（“句子1”，
“第2句”，
“第3句”，
“第4句”，
“第5句”，
“第6句”，
“第7句”，
“第8句”，
“第9句”，
“第10句”，
“第11句”，
“第12句”，
“第13句”，
“第14句”，
“第15句”，
“第16句”）
你可以试试下面的代码。
我在这个链接中发现了这一点。

自定义形状/颜色
s3d问题是我的传奇太大了，这就是为什么这不起作用，但无论如何，谢谢你的帮助：）我理解这个问题，你能在解决这个问题时与我分享吗？：）是的，当然，但不幸的是我还没有弄明白，所以现在，我在一个图形上打印绘图，在另一个图形上打印图例，然后我将它们组合在一起，得到一个图像：）
s3d <- scatterplot3d(iris[,1:3], pch = shapes, color=colors)
legend("bottom", legend = levels(iris$Species),
      col =  c("#999999", "#E69F00", "#56B4E9"), 
      pch = c(16, 17, 18), 
      inset = -0.25, xpd = TRUE, horiz = TRUE)