Day 11: 30-days to learn rgl, plotly, and gganimate - Learn How to Save rgl 3D Frames and Stitch Them Into an Animation With gganimate

 

Step 1: Set Up the Environment

1.     Install Required Packages
Ensure you have the following packages installed:

install.packages(c("rgl", "gganimate", "magick"))

The magick package will handle image processing for stitching frames.

2.     Load the Libraries
Load the necessary libraries:

library(rgl)

library(magick)

library(gganimate)

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Step 2: Create an rgl 3D Plot

1.     Generate Data for 3D Visualization
Create a 3D dataset for plotting:

set.seed(123)

x <- rnorm(100)

y <- rnorm(100)

z <- rnorm(100)

colors <- rainbow(100)

# Create a 3D scatter plot

plot3d(x, y, z, col = colors, size = 5, type = "s")

2.     Set Up Rotation or Camera Movements
Define the rotation sequence or camera viewpoints:

n_frames <- 36  # Number of frames

angles <- seq(0, 360, length.out = n_frames)

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Step 3: Save rgl Frames

1.     Create a Temporary Directory for Frames
Create a directory to save the images:

dir.create("rgl_frames")

2.     Save Each Frame
Loop through the angles and save an image for each:

for (i in seq_along(angles)) {

    rgl.viewpoint(theta = angles[i], phi = 30, fov = 60)

    snapshot3d(sprintf("rgl_frames/frame_%03d.png", i))

}

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Step 4: Combine Frames Into an Animation

1.     Use magick to Stitch Images
Load and combine the images:

frames <- list.files("rgl_frames", full.names = TRUE, pattern = "png")

animation <- image_read(frames) %>%

             image_animate(fps = 10)  # Set frames per second

2.     Save the Animation
Save the animation as a GIF:

image_write(animation, "rgl_animation.gif")

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Step 5: (Optional) Combine With gganimate

1.     Create a Data Frame for gganimate
If you want to integrate gganimate, create a dataset representing each frame's data:

animation_data <- data.frame(

    x = rep(x, n_frames),

    y = rep(y, n_frames),

    z = rep(z, n_frames),

    frame = rep(1:n_frames, each = length(x))

)

2.     Visualize With ggplot2 and gganimate
Use ggplot2 to create a dynamic scatter plot:

library(ggplot2)

ggplot(animation_data, aes(x = x, y = y, color = z, frame = frame)) +

    geom_point() +

    transition_manual(frame) +

    theme_minimal()

---

Step 6: Clean Up

1.     Remove Temporary Files
Delete the directory containing frames:

unlink("rgl_frames", recursive = TRUE)

2.     Review the Final Animation
Check the GIF and tweak the settings (e.g., angles, FPS) if needed.