Merge remote-tracking branch 'raytracing-import/master'

7 files changed, 285 insertions, 0 deletions

diff --git a/raytracing/src/CMakeLists.txt b/raytracing/src/CMakeLists.txt
new file mode 100644
index 0000000..c0dc29c
--- /dev/null
+++ b/raytracing/src/CMakeLists.txt
@@ -0,0 +1,9 @@
+set(LIB_SOURCES
+    vec3.cc
+    color.cc
+    ray.cc
+)
+
+add_library(RayTracerCore STATIC ${LIB_SOURCES})
+
+target_include_directories(RayTracerCore PUBLIC .)
\ No newline at end of file
diff --git a/raytracing/src/color.cc b/raytracing/src/color.cc
new file mode 100644
index 0000000..9a458bc
--- /dev/null
+++ b/raytracing/src/color.cc
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2026 Richard
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+#include "color.h"
+
+void write_color( std::ostream& out, const color& pixel_color )
+{
+  auto red = pixel_color.x();
+  auto green = pixel_color.y();
+  auto blue = pixel_color.z();
+
+  // Translate the [0,1] component values to the byte range [0,255].
+  const int rbyte = static_cast<int>( 255.999 * red );
+  const int gbyte = static_cast<int>( 255.999 * green );
+  const int bbyte = static_cast<int>( 255.999 * blue );
+
+  // Write out the pixel color components.
+  out << rbyte << ' ' << gbyte << ' ' << bbyte << '\n';
+}
\ No newline at end of file
diff --git a/raytracing/src/color.h b/raytracing/src/color.h
new file mode 100644
index 0000000..3e96a5b
--- /dev/null
+++ b/raytracing/src/color.h
@@ -0,0 +1,28 @@
+/*
+ * Copyright (C) 2026 Richard
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+#ifndef COLOR_H
+#define COLOR_H
+
+#include "vec3.h"
+
+#include <iostream>
+
+using color = vec3;
+
+void write_color( std::ostream& out, const color& pixel_color );
+
+#endif
\ No newline at end of file
diff --git a/raytracing/src/ray.cc b/raytracing/src/ray.cc
new file mode 100644
index 0000000..718fee2
--- /dev/null
+++ b/raytracing/src/ray.cc
@@ -0,0 +1,16 @@
+#include "ray.h"
+
+const point3& ray::origin() const
+{
+  return this->orig;
+}
+
+const vec3& ray::direction() const
+{
+  return this->dir;
+}
+
+point3 ray::at( double t ) const
+{
+  return this->orig + t * this->dir;
+}
\ No newline at end of file
diff --git a/raytracing/src/ray.h b/raytracing/src/ray.h
new file mode 100644
index 0000000..d455847
--- /dev/null
+++ b/raytracing/src/ray.h
@@ -0,0 +1,22 @@
+#ifndef RAY_H
+#define RAY_H
+
+#include "vec3.h"
+
+class ray
+{
+public:
+  ray() {}
+  ray( const point3& origin, const vec3& direction ) : orig( origin ), dir( direction ) {}
+
+  const point3& origin() const;
+  const vec3& direction() const;
+
+  point3 at( double t ) const;
+
+private:
+  point3 orig {};
+  vec3 dir {};
+};
+
+#endif
\ No newline at end of file
diff --git a/raytracing/src/vec3.cc b/raytracing/src/vec3.cc
new file mode 100644
index 0000000..4332c56
--- /dev/null
+++ b/raytracing/src/vec3.cc
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2026 Richard
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+#include "vec3.h"
+
+double vec3::x() const
+{
+  return e[0];
+}
+double vec3::y() const
+{
+  return e[1];
+}
+double vec3::z() const
+{
+  return e[2];
+}
+
+vec3 vec3::operator-() const
+{
+  return { -e[0], -e[1], -e[2] };
+}
+
+double vec3::operator[]( int i ) const
+{
+  return e.at( i );
+}
+
+double& vec3::operator[]( int i )
+{
+  return e.at( i );
+}
+
+vec3& vec3::operator+=( const vec3& other )
+{
+  e[0] += other.e[0];
+  e[1] += other.e[1];
+  e[2] += other.e[2];
+  return *this;
+}
+
+vec3& vec3::operator*=( double t )
+{
+  e[0] *= t;
+  e[1] *= t;
+  e[2] *= t;
+  return *this;
+}
+
+vec3& vec3::operator/=( double t )
+{
+  return *this *= 1 / t;
+}
+
+double vec3::length() const
+{
+  return std::sqrt( length_squared() );
+}
+
+double vec3::length_squared() const
+{
+  return e[0] * e[0] + e[1] * e[1] + e[2] * e[2];
+}
diff --git a/raytracing/src/vec3.h b/raytracing/src/vec3.h
new file mode 100644
index 0000000..a8b8265
--- /dev/null
+++ b/raytracing/src/vec3.h
@@ -0,0 +1,102 @@
+/*
+ * Copyright (C) 2026 Richard
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+#ifndef VEC_3
+#define VEC_3
+
+#include <array>
+#include <cmath>
+#include <iostream>
+
+class vec3
+{
+public:
+  std::array<double, 3> e;
+
+  vec3() : e { 0, 0, 0 } {}
+  vec3( double e0, double e1, double e2 ) : e { e0, e1, e2 } {}
+
+  double x() const;
+  double y() const;
+  double z() const;
+
+  vec3 operator-() const;
+  double operator[]( int i ) const;
+  double& operator[]( int i );
+  vec3& operator+=( const vec3& other );
+  vec3& operator*=( double t );
+  vec3& operator/=( double t );
+  double length() const;
+  double length_squared() const;
+};
+
+// point3 is just an alias for vec3, but useful for geometric clarity in the code.
+using point3 = vec3;
+
+// Vector Utility Functions
+
+inline std::ostream& operator<<( std::ostream& out, const vec3& v )
+{
+  return out << v.e[0] << ' ' << v.e[1] << ' ' << v.e[2];
+}
+
+inline vec3 operator+( const vec3& u, const vec3& v )
+{
+  return { u.e[0] + v.e[0], u.e[1] + v.e[1], u.e[2] + v.e[2] };
+}
+
+inline vec3 operator-( const vec3& u, const vec3& v )
+{
+  return { u.e[0] - v.e[0], u.e[1] - v.e[1], u.e[2] - v.e[2] };
+}
+
+inline vec3 operator*( const vec3& u, const vec3& v )
+{
+  return { u.e[0] * v.e[0], u.e[1] * v.e[1], u.e[2] * v.e[2] };
+}
+
+inline vec3 operator*( double t, const vec3& v )
+{
+  return { t * v.e[0], t * v.e[1], t * v.e[2] };
+}
+
+inline vec3 operator*( const vec3& v, double t )
+{
+  return t * v;
+}
+
+inline vec3 operator/( const vec3& v, double t )
+{
+  return ( 1 / t ) * v;
+}
+
+inline double dot( const vec3& u, const vec3& v )
+{
+  return u.e[0] * v.e[0] + u.e[1] * v.e[1] + u.e[2] * v.e[2];
+}
+
+inline vec3 cross( const vec3& u, const vec3& v )
+{
+  return {
+    u.e[1] * v.e[2] - u.e[2] * v.e[1], u.e[2] * v.e[0] - u.e[0] * v.e[2], u.e[0] * v.e[1] - u.e[1] * v.e[0] };
+}
+
+inline vec3 unit_vector( const vec3& v )
+{
+  return v / v.length();
+}
+
+#endif