R语言中如何实现Python Plotly的add_volume()功能？

我需要复现Python Plotly中用add_volume实现的曲面下体积填充效果，但R的Plotly没有这个函数，之前的尝试仅绘制了曲面，未实现体积填充，现提供可行方案：

完整实现代码 #

library(plotly)
library(grDevices)

# 定义曲面函数
f <- function(x, y) {
  cos(x) + sin(y) + 4
}

# 生成基础曲面数据
x <- seq(-5, 5, length.out = 100)
y <- seq(-5, 5, length.out = 100)
z <- outer(x, y, f)

# 生成目标区域的曲面数据
lower_x <- -1
upper_x <- 2
lower_y <- -2
upper_y <- 4
int_x <- seq(lower_x, upper_x, length.out = 50)
int_y <- seq(lower_y, upper_y, length.out = 70)
int_z <- outer(int_x, int_y, f)

# 生成体积填充所需的三维网格数据
lower_z <- 0
upper_z <- max(int_z)
nx <- 50
ny <- 50
nz <- 75
X <- seq(lower_x, upper_x, length.out = nx)
Y <- seq(lower_y, upper_y, length.out = ny)
Z <- seq(lower_z, upper_z, length.out = nz)
grid <- expand.grid(x = X, y = Y, z = Z)
grid$vals <- grid$z - f(grid$x, grid$y)

# 构建Plotly图形
fig <- plot_ly() %>%
  # 添加半透明基础曲面
  add_surface(x = ~x, y = ~y, z = ~z, 
              showscale = FALSE, opacity = 0.6, 
              colors = colorRampPalette(c('#fbb4ae', '#b3cde3', '#ccebc5'))(100)) %>%
  # 添加目标区域不透明曲面
  add_surface(x = ~int_x, y = ~int_y, z = ~int_z, 
              showscale = FALSE, opacity = 1, 
              colors = colorRampPalette(c('#fed976', '#fd8d3c', '#fc4e2a'))(100)) %>%
  # 用等值面模拟体积填充
  add_isosurface(
    x = grid$x, y = grid$y, z = grid$z,
    value = grid$vals,
    isomin = -upper_z, isomax = 0,
    surfacecount = 2,
    colorscale = list(c(0, '#fc4e2a'), c(1, '#fc4e2a')),
    showscale = FALSE,
    opacity = 0.5
  ) %>%
  # 设置布局参数
  layout(
    height = 600, width = 600,
    scene = list(
      zaxis = list(range = c(0, upper_z + 0.5)),
      camera = list(eye = list(x = 1.85, y = 1.85, z = 0.7))
    )
  )

fig

关键说明 #

• 用expand.grid生成三维网格点，替代Python的np.mgrid生成体数据
• 使用add_isosurface替代Python的add_volume：通过isomin=-upper_z和isomax=0限定填充区域（即z从0到曲面f(x,y)之间的空间）
• 颜色配置与原Python代码的视觉效果对齐，可根据需求调整颜色和透明度

内容的提问来源于stack exchange，提问作者stats_noob