Water Appears Opaque in render_highquality() Compared to rgl Preview and render_snapshot()

[danilyanedo7]

Water Appears Opaque in render_highquality() Compared to rgl Preview and render_snapshot()

Hi there! First of all, thank you for the amazing package — rayshader is an absolute game-changer for 3D mapping in R.

I'm currently visualizing a terrain with water features using rayshader. The issue I’m facing is with how water appears when rendering using render_highquality().

When I preview the scene using rgl::rglwidget() or even render using render_snapshot(), the water appears semi-transparent and natural — just how I want it. But when I use render_highquality() to produce a detailed image, the water turns completely dark and opaque, losing the nice translucent look.

---

# 2D map
rb %>%
  sphere_shade(texture = "desert") %>%
  add_shadow(rb_shadow, max_darken = 0.5) %>%
  add_shadow(rb_amb, max_darken = 0.5) %>%
  add_overlay(overlay_img, alphalayer = 0.85) %>%
  plot_map()

# 3D rendering
rb %>%
  sphere_shade(texture = "imhof1") %>%
  add_shadow(rb_shadow, max_darken = 0.5) %>%
  add_shadow(rb_amb, max_darken = 0.5) %>%
  add_overlay(overlay_3d, alphalayer = 0.9) %>%
  add_water(watermap, color = "lightblue") %>%
  plot_3d(rb,
          zscale = 130,
          fov = 30,
          theta = 210,
          phi = 21,
          windowsize = c(1200, 800),
          zoom = 0.6,
          water = FALSE, 
          waterdepth = 3, 
          wateralpha = 0.00001, 
          watercolor = "lightblue",
          waterlinecolor = "white", 
          waterlinealpha = 0.00001, 
          solid = TRUE)

# Camera adjustment
render_camera(phi = 9, zoom = 0.6, theta = 130, fov = 15)

# Snapshot — water looks great but lower quality
render_snapshot(clear = TRUE)

# High-quality render — water appears dark/opaque
render_highquality(filename = "laut_ambon2.png", preview = TRUE,
                   samples = 100,
                   sample_method = "sobol",
                   interactive = FALSE,
                   light = FALSE,
                   lightdirection = 280,
                   lightaltitude = c(30, 45),
                   environment_light = "air_museum_playground_4k.hdr",
                   intensity_env = 0.4,
                   rotate_env = 90,
                   parallel = TRUE,
                   width = 4000,
                   height = 2500)
![laut_ambon2](https://github.com/user-attachments/assets/8dc01e3c-c821-4cc2-be76-22a55669afde)


###  What I’ve Tried
- Tweaking `wateralpha`, `watercolor`, and `add_water()` settings.
- Enabling/disabling the `water` flag in `plot_3d()`.
- Using different HDRI environment lights.
- Switching between `sobol` and `random` sampling methods.

### What I’m Looking For
- Is it possible to replicate the nice translucent water effect from the `rgl` preview or `render_snapshot()` inside `render_highquality()`?
- Or is this a known limitation of `render_highquality()`?
- Any tips or workarounds for preserving the transparent/glassy water look at high quality?