From 72db397930fba78ffc07d8b7ba8cbdc001df3a49 Mon Sep 17 00:00:00 2001
From: "Dmitry V. Sokolov" <ha@haqr.eu>
Date: Mon, 21 Feb 2022 21:49:18 +0100
Subject: [PATCH] templates are no more

---
 geometry.h        | 61 -----------------------------------------------
 tinyraytracer.cpp | 32 +++++++++++++++++++------
 2 files changed, 25 insertions(+), 68 deletions(-)
 delete mode 100644 geometry.h

diff --git a/geometry.h b/geometry.h
deleted file mode 100644
index 4bafac7..0000000
--- a/geometry.h
+++ /dev/null
@@ -1,61 +0,0 @@
-#ifndef __GEOMETRY_H__
-#define __GEOMETRY_H__
-#include <cmath>
-#include <cassert>
-#include <iostream>
-
-template <size_t DIM> struct vec {
-          float& operator[](const size_t i)       { assert(i<DIM); return data[i]; }
-    const float& operator[](const size_t i) const { assert(i<DIM); return data[i]; }
-    float data[DIM] = {};
-};
-
-template<size_t DIM> vec<DIM> operator*(const vec<DIM> &lhs, const float rhs) {
-    vec<DIM> ret;
-    for (size_t i=DIM; i--; ret[i]=lhs[i]*rhs);
-    return ret;
-}
-
-template<size_t DIM> float operator*(const vec<DIM>& lhs, const vec<DIM>& rhs) {
-    float ret = 0;
-    for (size_t i=DIM; i--; ret+=lhs[i]*rhs[i]);
-    return ret;
-}
-
-template<size_t DIM> vec<DIM> operator+(vec<DIM> lhs, const vec<DIM>& rhs) {
-    for (size_t i=DIM; i--; lhs[i]+=rhs[i]);
-    return lhs;
-}
-
-template<size_t DIM> vec<DIM> operator-(vec<DIM> lhs, const vec<DIM>& rhs) {
-    for (size_t i=DIM; i--; lhs[i]-=rhs[i]);
-    return lhs;
-}
-
-template<size_t DIM> vec<DIM> operator-(const vec<DIM> &lhs) {
-    return lhs*(-1.f);
-}
-
-template <> struct vec<3> {
-          float& operator[](const size_t i)       { assert(i<3); return i==0 ? x : (1==i ? y : z); }
-    const float& operator[](const size_t i) const { assert(i<3); return i==0 ? x : (1==i ? y : z); }
-    float norm() { return std::sqrt(x*x+y*y+z*z); }
-    vec<3> & normalize(float l=1) { *this = (*this)*(l/norm()); return *this; }
-    float x = 0, y = 0, z = 0;
-};
-
-typedef vec<3> vec3;
-typedef vec<4> vec4;
-
-vec3 cross(vec3 v1, vec3 v2) {
-    return { v1.y*v2.z - v1.z*v2.y, v1.z*v2.x - v1.x*v2.z, v1.x*v2.y - v1.y*v2.x };
-}
-
-template <size_t DIM> std::ostream& operator<<(std::ostream& out, const vec<DIM>& v) {
-    for (size_t i=0; i<DIM; i++)
-        out << v[i] << " " ;
-    return out ;
-}
-
-#endif //__GEOMETRY_H__
-
diff --git a/tinyraytracer.cpp b/tinyraytracer.cpp
index ec7c122..62067ab 100644
--- a/tinyraytracer.cpp
+++ b/tinyraytracer.cpp
@@ -2,7 +2,25 @@
 #include <fstream>
 #include <vector>
 #include <algorithm>
-#include "geometry.h"
+#include <cassert>
+#include <cmath>
+
+struct vec3 {
+    float x=0, y=0, z=0;
+          float& operator[](const size_t i)       { assert(i<3); return i==0 ? x : (1==i ? y : z); }
+    const float& operator[](const size_t i) const { assert(i<3); return i==0 ? x : (1==i ? y : z); }
+    vec3  operator*(const float v) const { return {x*v, y*v, z*v};       }
+    float operator*(const vec3& v) const { return x*v.x + y*v.y + z*v.z; }
+    vec3  operator+(const vec3& v) const { return {x+v.x, y+v.y, z+v.z}; }
+    vec3  operator-(const vec3& v) const { return {x-v.x, y-v.y, z-v.z}; }
+    vec3  operator-()              const { return {-x, -y, -z};          }
+    float norm() const { return std::sqrt(x*x+y*y+z*z); }
+    vec3 normalized() const { return (*this)*(1.f/norm()); }
+};
+
+vec3 cross(const vec3 v1, const vec3 v2) {
+    return { v1.y*v2.z - v1.z*v2.y, v1.z*v2.x - v1.x*v2.z, v1.x*v2.y - v1.y*v2.x };
+}
 
 struct Light {
     vec3 position;
@@ -11,7 +29,7 @@ struct Light {
 
 struct Material {
     float refractive_index = 1;
-    vec4 albedo = {1,0,0,0};
+    float albedo[4] = {1,0,0,0};
     vec3 diffuse_color = {0,0,0};
     float specular_exponent = 0;
 };
@@ -72,7 +90,7 @@ bool scene_intersect(const vec3 &orig, const vec3 &dir, vec3 &hit, vec3 &N, Mate
         if (ray_sphere_intersect(orig, dir, s, dist_i) && dist_i < spheres_dist) {
             spheres_dist = dist_i;
             hit = orig + dir*dist_i;
-            N = (hit - s.center).normalize();
+            N = (hit - s.center).normalized();
             material = s.material;
         }
     }
@@ -98,14 +116,14 @@ vec3 cast_ray(const vec3 &orig, const vec3 &dir, size_t depth=0) {
     if (depth>4 || !scene_intersect(orig, dir, point, N, material))
         return vec3{0.2, 0.7, 0.8}; // background color
 
-    vec3 reflect_dir = reflect(dir, N).normalize();
-    vec3 refract_dir = refract(dir, N, material.refractive_index).normalize();
+    vec3 reflect_dir = reflect(dir, N).normalized();
+    vec3 refract_dir = refract(dir, N, material.refractive_index).normalized();
     vec3 reflect_color = cast_ray(point, reflect_dir, depth + 1);
     vec3 refract_color = cast_ray(point, refract_dir, depth + 1);
 
     float diffuse_light_intensity = 0, specular_light_intensity = 0;
     for (const Light light : lights) {
-        vec3 light_dir = (light.position - point).normalize();
+        vec3 light_dir = (light.position - point).normalized();
 
         vec3 shadow_pt, trashnrm;
         Material trashmat;
@@ -130,7 +148,7 @@ int main() {
             float dir_x =  (i + 0.5) -  width/2.;
             float dir_y = -(j + 0.5) + height/2.;    // this flips the image at the same time
             float dir_z = -height/(2.*tan(fov/2.));
-            framebuffer[i+j*width] = cast_ray(vec3{0,0,0}, vec3{dir_x, dir_y, dir_z}.normalize());
+            framebuffer[i+j*width] = cast_ray(vec3{0,0,0}, vec3{dir_x, dir_y, dir_z}.normalized());
         }
     }