From ae66bb7bf28bd495d38241b643144956c2f9af91 Mon Sep 17 00:00:00 2001
From: Bernie Innocenti <bernie@codewiz.org>
Date: Sat, 8 Apr 2017 12:46:39 -0400
Subject: [PATCH] Adjust mandelwow z limits and make glow fade non-linearly
 (tanh).

---
 mandelwow.rs | 13 +++++++------
 sound.rs     |  2 --
 2 files changed, 7 insertions(+), 8 deletions(-)

diff --git a/mandelwow.rs b/mandelwow.rs
index 4c5d25e..80c46d4 100644
--- a/mandelwow.rs
+++ b/mandelwow.rs
@@ -84,8 +84,8 @@ fn mandelwow_program(display: &glium::Display) -> glium::Program {
                         float zx2 = zx * zx;
                         float zy2 = zy * zy;
                         if (zx2 * zy2 > 4.0) {
-                          float index = 1.0 - float(iter) / float(maxiter);
-                          f_color = vec4(index, index * 0.5, index, index * 0.5);
+                          float index = float(iter) / float(maxiter);
+                          f_color = vec4(index, 0.1, 0.5 - index / 2, 0.8 - index);
                           return;
                         }
                         zy = zx * zy * 2.0 + c.y;
@@ -252,12 +252,13 @@ fn mandelwow(display: &glium::Display,
              bounds: &Cube,
              mandel_w: f32) {
     let mut z0 = [mandel_w, 0f32];
-    let zres = 50;
+    let zres = 30;
     let zmin = bounds.zmin;
     let zmax = bounds.zmax;
     let zstep = (zmax - zmin) / zres as f32;
     let mut zy = zmin;
-    for _ in 0..zres {
+    // zres + 1 to reach the other face of the cube (fencepost error)
+    for _ in 0..(zres + 1) {
         z0[1] = zy;
         zy += zstep;
 
@@ -307,8 +308,8 @@ fn main() {
             xmax:  0.7,
             ymin: -1.0,
             ymax:  1.0,
-            zmin: -1.2,
-            zmax:  1.2,
+            zmin: -1.1,
+            zmax:  1.1,
         };
 
         // Vary the wow factor to slice the Mandelwow along its 4th dimension.
diff --git a/sound.rs b/sound.rs
index 80afd5c..4b94686 100644
--- a/sound.rs
+++ b/sound.rs
@@ -1,5 +1,3 @@
-#[macro_use]
-
 use libxm::XMContext;
 use sdl2;
 use sdl2::audio::{AudioCallback, AudioDevice, AudioSpecDesired};
-- 
2.25.1