From 878b441742390628f731d7d23597395c9a61e9cc Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop+git@gmail.com>
Date: Wed, 12 Oct 2011 12:45:15 -0400
Subject: [PATCH] rework addRing(); consider LBStruct.offset the offset when
 created

---
 modes/Tunnel.cc | 15 ++++++++++-----
 modes/Tunnel.h  |  2 +-
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/modes/Tunnel.cc b/modes/Tunnel.cc
index 1357846..80e9643 100644
--- a/modes/Tunnel.cc
+++ b/modes/Tunnel.cc
@@ -35,6 +35,12 @@ bool Tunnel::expose (GnomeScreensaver & gs)
         m_last_ticks = gs.getTicks();
     uint64_t ticks = gs.getTicks();
     int elapsed = ticks - m_last_ticks;
+    m_offset += XLATE_RATE * elapsed;
+    while (m_offset - m_last_ring_offset > RING_LAYER_DIST)
+    {
+        m_last_ring_offset += RING_LAYER_DIST;
+        addRing(m_last_ring_offset);
+    }
 
     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
@@ -43,7 +49,7 @@ bool Tunnel::expose (GnomeScreensaver & gs)
             it++)
     {
         glPushMatrix();
-        glTranslatef(0, m_offset + it->offset, 0);
+        glTranslatef(0, m_offset - it->offset, 0);
         glRotatef(it->trot, 0, 1, 0);
         glTranslatef(RING_RADIUS, 0, 0);
         glRotatef(-90.0, 0, 0, 1);
@@ -58,14 +64,14 @@ bool Tunnel::expose (GnomeScreensaver & gs)
     return true;
 }
 
-void Tunnel::addRing()
+void Tunnel::addRing(double offset)
 {
     for (int j = 0; j < N_LOGOS_PER_RING; j++)
     {
         float zrot = ((j + m_ring_rot_idx) & 0x3) * 90.0;
         float trot = j * 360.0 / N_LOGOS_PER_RING;
         LBStruct lbs = {
-            m_offset,
+            offset,
             zrot,
             trot,
             {0, 0, 1}
@@ -90,8 +96,7 @@ bool Tunnel::configure (GnomeScreensaver & gs)
 
     for (int i = 0; i <= N_INITIAL_LAYERS; i++)
     {
-        m_offset = (N_INITIAL_LAYERS - i) * RING_LAYER_DIST,
-        addRing();
+        addRing((i - N_INITIAL_LAYERS) * RING_LAYER_DIST);
     }
 
     m_offset = 0.0;
diff --git a/modes/Tunnel.h b/modes/Tunnel.h
index 0ba1021..673b6c6 100644
--- a/modes/Tunnel.h
+++ b/modes/Tunnel.h
@@ -23,7 +23,7 @@ class Tunnel : public Mode
             float spin_axis[3];
         } LBStruct;
     protected:
-        void addRing();
+        void addRing(double offset);
         LogoBox m_logobox;
         uint64_t m_last_ticks;
         std::list<LBStruct> m_logos;