diff --git a/client/src/lib.rs b/client/src/lib.rs
index d5bde04a28..fc1318f95a 100644
--- a/client/src/lib.rs
+++ b/client/src/lib.rs
@@ -30,9 +30,6 @@ use common::{
     vol::RectVolSize,
     ChatType,
 };
-// TODO: remove CONFIG dependency by passing CONFIG.sea_level explicitly.
-// In general any WORLD dependencies need to go away ASAP... we should see if we
-// can pull out map drawing into common somehow.
 use hashbrown::HashMap;
 use image::DynamicImage;
 use log::{error, warn};
@@ -44,10 +41,9 @@ use std::{
 };
 use uvth::{ThreadPool, ThreadPoolBuilder};
 use vek::*;
-use world::{
-    sim::{neighbors, Alt},
-    CONFIG,
-};
+// TODO: remove world dependencies.  We should see if we
+// can pull out map drawing into common somehow.
+use world::sim::{neighbors, Alt};
 
 // The duration of network inactivity until the player is kicked
 // @TODO: in the future, this should be configurable on the server
@@ -135,9 +131,8 @@ impl Client {
                 assert_eq!(rgba.len(), (map_size.x * map_size.y) as usize);
                 let [west, east] = world_map.horizons;
                 let scale_angle =
-                    |a: u8| (a as Alt / 255.0 / <Alt as FloatConst>::FRAC_2_PI()).tan();
-                let scale_height =
-                    |h: u8| h as Alt * max_height as Alt / 255.0 + CONFIG.sea_level as Alt;
+                    |a: u8| (a as Alt / 255.0 * <Alt as FloatConst>::FRAC_PI_2()).tan();
+                let scale_height = |h: u8| h as Alt / 255.0 * max_height as Alt;
 
                 log::debug!("Preparing image...");
                 let unzip_horizons = |(angles, heights): (Vec<_>, Vec<_>)| {
@@ -154,8 +149,8 @@ impl Client {
                 map_config.lgain = 1.0;
                 map_config.gain = max_height;
                 map_config.horizons = Some(&horizons);
-                let rescale_height =
-                    |h: Alt| (h as f32 - map_config.focus.z as f32) / map_config.gain as f32;
+                map_config.focus.z = 0.0;
+                let rescale_height = |h: Alt| (h / max_height as Alt) as f32;
                 let bounds_check = |pos: Vec2<i32>| {
                     pos.reduce_partial_min() >= 0
                         && pos.x < map_size.x as i32
@@ -211,7 +206,7 @@ impl Client {
                             let posi = pos.y as usize * map_size.x as usize + pos.x as usize;
                             scale_height(rgba[posi].to_le_bytes()[3])
                         } else {
-                            CONFIG.sea_level as Alt
+                            0.0
                         })
                     },
                     |pos, (r, g, b, a)| {
diff --git a/world/src/sim/map.rs b/world/src/sim/map.rs
index 311ed32d6e..2835743fbb 100644
--- a/world/src/sim/map.rs
+++ b/world/src/sim/map.rs
@@ -273,6 +273,8 @@ impl<'a> MapConfig<'a> {
             })
             .map(|sample| {
                 // TODO: Eliminate the redundancy between this and the block renderer.
+                let alt = sample.alt;
+                let basement = sample.basement;
                 let grass_depth = (1.5 + 2.0 * sample.chaos).min(alt - basement);
                 let wposz = if is_basement { basement } else { alt };
                 if is_basement && wposz < alt - grass_depth {
@@ -615,7 +617,8 @@ impl<'a> MapConfig<'a> {
                     })
                     .map(|(angle, height)| {
                         let w = 0.1;
-                        if angle != 0.0 && light_direction.x != 0.0 {
+                        let height = (height - alt as Alt * gain as Alt).max(0.0);
+                        if angle != 0.0 && light_direction.x != 0.0 && height != 0.0 {
                             let deltax = height / angle;
                             let lighty = (light_direction.y / light_direction.x * deltax).abs();
                             let deltay = lighty - height;
diff --git a/world/src/sim/mod.rs b/world/src/sim/mod.rs
index c177885b3b..dafbbda996 100644
--- a/world/src/sim/mod.rs
+++ b/world/src/sim/mod.rs
@@ -1314,9 +1314,8 @@ impl WorldSim {
         // Build a horizon map.
         let scale_angle =
             |angle: Alt| (angle.atan() * <Alt as FloatConst>::FRAC_2_PI() * 255.0).floor() as u8;
-        let scale_height = |height: Alt| {
-            ((height - CONFIG.sea_level as Alt) * 255.0 / self.max_height as Alt).floor() as u8
-        };
+        let scale_height =
+            |height: Alt| (height as Alt * 255.0 / self.max_height as Alt).floor() as u8;
         let horizons = get_horizon_map(
             map_config.lgain,
             Aabr {
diff --git a/world/src/sim/util.rs b/world/src/sim/util.rs
index e194a9aed5..d25c115b45 100644
--- a/world/src/sim/util.rs
+++ b/world/src/sim/util.rs
@@ -392,6 +392,10 @@ pub fn get_horizon_map<F: Float + Sync, A: Send, H: Send>(
     to_angle: impl Fn(F) -> A + Sync,
     to_height: impl Fn(F) -> H + Sync,
 ) -> Result<[(Vec<A>, Vec<H>); 2], ()> {
+    if maxh < minh {
+        // maxh must be greater than minh
+        return Err(());
+    }
     let map_size = Vec2::<i32>::from(bounds.size()).map(|e| e as usize);
     let map_len = map_size.product();
 
@@ -421,9 +425,11 @@ pub fn get_horizon_map<F: Float + Sync, A: Send, H: Send>(
                 // March in the given direction.
                 let maxdx = maxdx(wposi.x as isize);
                 let mut slope = F::zero();
-                let mut max_height = F::zero();
                 let h0 = h(posi);
-                if h0 >= minh {
+                let h = if h0 < minh {
+                    F::zero()
+                } else {
+                    let mut max_height = F::zero();
                     let maxdz = maxh - h0;
                     let posi = posi as isize;
                     for deltax in 1..maxdx {
@@ -441,9 +447,9 @@ pub fn get_horizon_map<F: Float + Sync, A: Send, H: Send>(
                             max_height = h_j_act;
                         }
                     }
-                }
+                    h0 - minh + max_height
+                };
                 let a = slope * lgain;
-                let h = h0 + max_height;
                 (to_angle(a), to_height(h))
             })
             .unzip_into_vecs(&mut angles, &mut heights);