From 1b75342fdec4f58aecb35869588a247e9ddc066a Mon Sep 17 00:00:00 2001
From: Samuel Fadel <samuelfadel@gmail.com>
Date: Sun, 17 Jan 2016 20:50:07 +0100
Subject: ColorScale: minor update to color sampling and generation algorithms.

---
 colorscale.cpp | 5 ++---
 colorscale.h   | 9 +++++----
 2 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/colorscale.cpp b/colorscale.cpp
index e4e2063..38898c3 100644
--- a/colorscale.cpp
+++ b/colorscale.cpp
@@ -63,15 +63,14 @@ QColor ColorScale::color(float t) const
     }
 
     // find which colors in the scale are adjacent to ours
-    float step = 1.0 / m_colors.size();
-    int i = int(t / step);
+    int i = int(t * m_colors.size());
     int j = i + 1;
-
     if (i >= m_colors.size() - 1) {
         return QColor(m_colors.last());
     }
 
     // normalize t between the two colors
+    float step = 1.0f / m_colors.size();
     t = (t - i*step) / (j*step - i*step);
     return lerp(m_colors[i], m_colors[j], t);
 }
diff --git a/colorscale.h b/colorscale.h
index 1be315f..5974cef 100644
--- a/colorscale.h
+++ b/colorscale.h
@@ -19,6 +19,7 @@ public:
     void setExtents(float min, float max);
     float min() const { return m_min; }
     float max() const { return m_max; }
+    int numColors() const { return m_colors.size(); }
 
     template<typename OutputIterator>
     void sample(int samples, OutputIterator it) const;
@@ -37,11 +38,11 @@ void ColorScale::sample(int samples, OutputIterator it) const
 
     float step = (max() - min()) / samples;
     qreal r, g, b;
-    for (float t = min(); t < max(); t += step) {
+    for (float t = min(); samples-- > 0; t += step) {
         color(t).getRgbF(&r, &g, &b);
-        *it = r; it++;
-        *it = g; it++;
-        *it = b; it++;
+        *it++ = r;
+        *it++ = g;
+        *it++ = b;
     }
 }
 
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