Replace color with pbr-book inspired Spectrum class

3 files changed, 123 insertions, 0 deletions

diff --git a/src/core/common.hpp b/src/core/common.hpp
index fd219bf..a3e682e 100644
--- a/src/core/common.hpp
+++ b/src/core/common.hpp
@@ -1,6 +1,10 @@
 #ifndef COMMON_H
 #define COMMON_H
 
+#include <limits>
+
 #define ZERO_APPROX 1e-6
 
+#define INFINITY std::numeric_limits<double>::infinity()
+
 #endif
diff --git a/src/core/spectrum.cpp b/src/core/spectrum.cpp
new file mode 100644
index 0000000..d53cf49
--- /dev/null
+++ b/src/core/spectrum.cpp
@@ -0,0 +1,90 @@
+#include "spectrum.hpp"
+
+static double clamp(double v, double low = 0, double high = 0) {
+    if (v < low) {
+        return low;
+    } 
+    if (v > high) {
+        return high;
+    }
+    return v;
+}
+
+Spectrum::Spectrum(double v) {
+    c[0] = v;
+    c[1] = v;
+    c[2] = v;
+}
+
+Spectrum Spectrum::FromRGB(double r, double g, double b) {
+    Spectrum ret;
+    ret.c[0] = r;
+    ret.c[1] = g;
+    ret.c[2] = b;
+
+    return ret;
+}
+
+Spectrum &Spectrum::operator+=(const Spectrum &o) {
+    c[0] += o.c[0];
+    c[1] += o.c[1];
+    c[2] += o.c[2];
+
+    return *this;
+}
+
+Spectrum &Spectrum::operator*=(double o) {
+    c[0] *= o;
+    c[1] *= o;
+    c[2] *= o;
+
+    return *this;
+}
+
+Spectrum Spectrum::operator+(const Spectrum &o) const {
+    Spectrum ret = *this;
+
+    ret.c[0] += o.c[0];
+    ret.c[1] += o.c[1];
+    ret.c[2] += o.c[2];
+
+    return ret;
+}
+
+Spectrum Spectrum::operator-(const Spectrum &o) const {
+    Spectrum ret = *this;
+
+    ret.c[0] -= o.c[0];
+    ret.c[1] -= o.c[1];
+    ret.c[2] -= o.c[2];
+
+    return ret;
+}
+
+Spectrum Spectrum::operator*(const Spectrum &o) const {
+    Spectrum ret = *this;
+
+    ret.c[0] *= o.c[0];
+    ret.c[1] *= o.c[1];
+    ret.c[2] *= o.c[2];
+
+    return ret;
+}
+
+Spectrum Spectrum::operator/(const Spectrum &o) const {
+    Spectrum ret = *this;
+
+    ret.c[0] /= o.c[0];
+    ret.c[1] /= o.c[1];
+    ret.c[2] /= o.c[2];
+
+    return ret;
+}
+
+Spectrum Spectrum::clamp(double low, double high) const {
+    Spectrum ret;
+    ret.c[0] = ::clamp(c[0], low, high);
+    ret.c[1] = ::clamp(c[1], low, high);
+    ret.c[2] = ::clamp(c[2], low, high);
+    return ret;
+}
diff --git a/src/core/spectrum.hpp b/src/core/spectrum.hpp
new file mode 100644
index 0000000..de9355d
--- /dev/null
+++ b/src/core/spectrum.hpp
@@ -0,0 +1,29 @@
+#ifndef SPECTRUM_H
+#define SPECTRUM_H
+
+#include "core/common.hpp"
+
+// Contains a RGB spectrum value
+class Spectrum {
+public:
+    Spectrum(double v = 0);
+    static Spectrum FromRGB(double r, double g, double b);
+
+    Spectrum &operator+=(const Spectrum &o);
+    Spectrum &operator*=(double o);
+    Spectrum operator+(const Spectrum &o) const;
+    Spectrum operator-(const Spectrum &o) const;
+    Spectrum operator*(const Spectrum &o) const;
+    Spectrum operator/(const Spectrum &o) const;
+
+    Spectrum clamp(double low = 0, double high = INFINITY) const;
+
+    double R() const { return c[0]; }
+    double G() const { return c[1]; }
+    double B() const { return c[2]; }
+
+private:
+    double c[3];
+};
+
+#endif