Distribute src/common to individual book sources

With the exception of the invariant STB image library and associated
wrapper, this change moves all of the files out from common to each book
that requires each file.

In addition, common headers that included changes from subsequent books
have been reverted to their state at the end of each book.

This change also fixes up some issues found during this exercise.

Author: hollasch

CMakeLists.txt

@@ -14,58 +14,66 @@ set ( CMAKE_CXX_STANDARD_REQUIRED ON )
 set ( CMAKE_CXX_EXTENSIONS        OFF )
 
 # Source
-set ( COMMON_ALL
-  src/common/rtweekend.h
-  src/common/color.h
-  src/common/interval.h
-  src/common/ray.h
-  src/common/vec3.h
-)
 
 set ( SOURCE_ONE_WEEKEND
-  ${COMMON_ALL}
   src/InOneWeekend/camera.h
+  src/InOneWeekend/color.h
   src/InOneWeekend/hittable.h
   src/InOneWeekend/hittable_list.h
+  src/InOneWeekend/interval.h
   src/InOneWeekend/material.h
+  src/InOneWeekend/ray.h
+  src/InOneWeekend/rtweekend.h
   src/InOneWeekend/sphere.h
+  src/InOneWeekend/vec3.h
+
   src/InOneWeekend/main.cc
 )
 
 set ( SOURCE_NEXT_WEEK
-  ${COMMON_ALL}
-  src/common/aabb.h
   src/common/external/stb_image.h
-  src/common/perlin.h
   src/common/rtw_stb_image.h
-  src/common/texture.h
+  src/TheNextWeek/aabb.h
   src/TheNextWeek/bvh.h
   src/TheNextWeek/camera.h
+  src/TheNextWeek/color.h
   src/TheNextWeek/constant_medium.h
   src/TheNextWeek/hittable.h
   src/TheNextWeek/hittable_list.h
+  src/TheNextWeek/interval.h
   src/TheNextWeek/material.h
+  src/TheNextWeek/perlin.h
   src/TheNextWeek/quad.h
+  src/TheNextWeek/ray.h
+  src/TheNextWeek/rtweekend.h
   src/TheNextWeek/sphere.h
+  src/TheNextWeek/texture.h
+  src/TheNextWeek/vec3.h
+
   src/TheNextWeek/main.cc
 )
 
 set ( SOURCE_REST_OF_YOUR_LIFE
-  ${COMMON_ALL}
-  src/common/aabb.h
   src/common/external/stb_image.h
-  src/common/perlin.h
   src/common/rtw_stb_image.h
-  src/common/texture.h
-  src/TheRestOfYourLife/bvh.h
+  src/TheRestOfYourLife/aabb.h
   src/TheRestOfYourLife/camera.h
+  src/TheRestOfYourLife/color.h
+  src/TheRestOfYourLife/constant_medium.h
   src/TheRestOfYourLife/hittable.h
   src/TheRestOfYourLife/hittable_list.h
+  src/TheRestOfYourLife/interval.h
   src/TheRestOfYourLife/material.h
   src/TheRestOfYourLife/onb.h
   src/TheRestOfYourLife/pdf.h
+  src/TheRestOfYourLife/perlin.h
   src/TheRestOfYourLife/quad.h
+  src/TheRestOfYourLife/ray.h
+  src/TheRestOfYourLife/rtweekend.h
   src/TheRestOfYourLife/sphere.h
+  src/TheRestOfYourLife/texture.h
+  src/TheRestOfYourLife/vec3.h
+
   src/TheRestOfYourLife/main.cc
 )
 

books/RayTracingInOneWeekend.html

@@ -467,9 +467,7 @@
       public:
         ray() {}
 
-        ray(const point3& origin, const vec3& direction)
-          : orig(origin), dir(direction)
-        {}
+        ray(const point3& origin, const vec3& direction) : orig(origin), dir(direction) {}
 
         point3 origin() const  { return orig; }
         vec3 direction() const { return dir; }
@@ -2172,9 +2170,9 @@
 
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ C++ highlight
         // Apply a linear to gamma transform for gamma 2
-        r = linear_to_gamma(r)
-        g = linear_to_gamma(g)
-        b = linear_to_gamma(b)
+        r = linear_to_gamma(r);
+        g = linear_to_gamma(g);
+        b = linear_to_gamma(b);
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ C++
 
         // Write the translated [0,255] value of each color component.

books/RayTracingTheRestOfYourLife.html

@@ -3668,11 +3668,10 @@
 
 
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ C++ highlight
-        // Replace NaN components with zero. See explanation in Ray Tracing: The Rest of Your Life.
+        // Replace NaN components with zero.
         if (r != r) r = 0.0;
         if (g != g) g = 0.0;
         if (b != b) b = 0.0;
-
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ C++
 
         // Divide the color by the number of samples and gamma-correct for gamma=2.0.

src/InOneWeekend/color.h

@@ -0,0 +1,49 @@
+#ifndef COLOR_H
+#define COLOR_H
+//==============================================================================================
+// Originally written in 2020 by Peter Shirley <[email protected]>
+//
+// To the extent possible under law, the author(s) have dedicated all copyright and related and
+// neighboring rights to this software to the public domain worldwide. This software is
+// distributed without any warranty.
+//
+// You should have received a copy (see file COPYING.txt) of the CC0 Public Domain Dedication
+// along with this software. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
+//==============================================================================================
+
+#include "vec3.h"
+
+#include <iostream>
+
+using color = vec3;
+
+inline double linear_to_gamma(double linear_component)
+{
+    return sqrt(linear_component);
+}
+
+void write_color(std::ostream &out, color pixel_color, int samples_per_pixel) {
+    auto r = pixel_color.x();
+    auto g = pixel_color.y();
+    auto b = pixel_color.z();
+
+    // Divide the color by the number of samples.
+    auto scale = 1.0 / samples_per_pixel;
+    r *= scale;
+    g *= scale;
+    b *= scale;
+
+    // Apply a linear to gamma transform for gamma 2
+    r = linear_to_gamma(r);
+    g = linear_to_gamma(g);
+    b = linear_to_gamma(b);
+
+    // Write the translated [0,255] value of each color component.
+    static const interval intensity(0.000, 0.999);
+    out << static_cast<int>(256 * intensity.clamp(r)) << ' '
+        << static_cast<int>(256 * intensity.clamp(g)) << ' '
+        << static_cast<int>(256 * intensity.clamp(b)) << '\n';
+}
+
+
+#endif

src/InOneWeekend/interval.h

@@ -0,0 +1,50 @@
+#ifndef INTERVAL_H
+#define INTERVAL_H
+//==============================================================================================
+// To the extent possible under law, the author(s) have dedicated all copyright and related and
+// neighboring rights to this software to the public domain worldwide. This software is
+// distributed without any warranty.
+//
+// You should have received a copy (see file COPYING.txt) of the CC0 Public Domain Dedication
+// along with this software. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
+//==============================================================================================
+
+class interval {
+  public:
+    double min, max;
+
+    interval() : min(+infinity), max(-infinity) {} // Default interval is empty
+
+    interval(double _min, double _max) : min(_min), max(_max) {}
+
+    double size() const {
+        return max - min;
+    }
+
+    interval expand(double delta) const {
+        auto padding = delta/2;
+        return interval(min - padding, max + padding);
+    }
+
+    bool contains(double x) const {
+        return min <= x && x <= max;
+    }
+
+    bool surrounds(double x) const {
+        return min < x && x < max;
+    }
+
+    double clamp(double x) const {
+        if (x < min) return min;
+        if (x > max) return max;
+        return x;
+    }
+
+    static const interval empty, universe;
+};
+
+const interval interval::empty    = interval(+infinity, -infinity);
+const interval interval::universe = interval(-infinity, +infinity);
+
+
+#endif

src/InOneWeekend/ray.h

@@ -0,0 +1,35 @@
+#ifndef RAY_H
+#define RAY_H
+//==============================================================================================
+// Originally written in 2016 by Peter Shirley <[email protected]>
+//
+// To the extent possible under law, the author(s) have dedicated all copyright and related and
+// neighboring rights to this software to the public domain worldwide. This software is
+// distributed without any warranty.
+//
+// You should have received a copy (see file COPYING.txt) of the CC0 Public Domain Dedication
+// along with this software. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
+//==============================================================================================
+
+#include "vec3.h"
+
+
+class ray {
+  public:
+    ray() {}
+
+    ray(const point3& origin, const vec3& direction) : orig(origin), dir(direction) {}
+
+    point3 origin() const  { return orig; }
+    vec3 direction() const { return dir; }
+
+    point3 at(double t) const {
+        return orig + t*dir;
+    }
+
+  private:
+    point3 orig;
+    vec3 dir;
+};
+
+#endif

src/InOneWeekend/rtweekend.h

@@ -0,0 +1,52 @@
+#ifndef RTWEEKEND_H
+#define RTWEEKEND_H
+//==============================================================================================
+// To the extent possible under law, the author(s) have dedicated all copyright and related and
+// neighboring rights to this software to the public domain worldwide. This software is
+// distributed without any warranty.
+//
+// You should have received a copy (see file COPYING.txt) of the CC0 Public Domain Dedication
+// along with this software. If not, see <http://creativecommons.org/publicdomain/zero/1.0/>.
+//==============================================================================================
+
+#include <cmath>
+#include <cstdlib>
+#include <limits>
+#include <memory>
+
+
+// Usings
+
+using std::shared_ptr;
+using std::make_shared;
+using std::sqrt;
+
+// Constants
+
+const double infinity = std::numeric_limits<double>::infinity();
+const double pi = 3.1415926535897932385;
+
+// Utility Functions
+
+inline double degrees_to_radians(double degrees) {
+    return degrees * pi / 180.0;
+}
+
+inline double random_double() {
+    // Returns a random real in [0,1).
+    return rand() / (RAND_MAX + 1.0);
+}
+
+inline double random_double(double min, double max) {
+    // Returns a random real in [min,max).
+    return min + (max-min)*random_double();
+}
+
+// Common Headers
+
+#include "interval.h"
+#include "ray.h"
+#include "vec3.h"
+
+
+#endif