Declare image parameters as const

Author: hollasch

books/RayTracingInOneWeekend.html

@@ -70,8 +70,8 @@
     #include <iostream>
 
     int main() {
-        int image_width = 200;
-        int image_height = 100;
+        const int image_width = 200;
+        const int image_height = 100;
 
         std::cout << "P3\n" << image_width << ' ' << image_height << "\n255\n";
 
@@ -318,8 +318,8 @@
     #include <iostream>
 
     int main() {
-        int image_width = 200;
-        int image_height = 100;
+        const int image_width = 200;
+        const int image_height = 100;
 
         std::cout << "P3\n" << image_width << ' ' << image_height << "\n255\n";
 
@@ -419,9 +419,11 @@
     }
 
     int main() {
-        int image_width = 200;
-        int image_height = 100;
+        const int image_width = 200;
+        const int image_height = 100;
+
         std::cout << "P3\n" << image_width << " " << image_height << "\n255\n";
+
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ C++ highlight
         vec3 lower_left_corner(-2.0, -1.0, -1.0);
         vec3 horizontal(4.0, 0.0, 0.0);
@@ -1078,8 +1080,8 @@
     }
 
     int main() {
-        int image_width = 200;
-        int image_height = 100;
+        const int image_width = 200;
+        const int image_height = 100;
 
         std::cout << "P3\n" << image_width << ' ' << image_height << "\n255\n";
 
@@ -1260,10 +1262,10 @@
 
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ C++
     int main() {
-        int image_width = 200;
-        int image_height = 100;
+        const int image_width = 200;
+        const int image_height = 100;
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ C++ highlight
-        int samples_per_pixel = 100;
+        const int samples_per_pixel = 100;
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ C++
 
         std::cout << "P3\n" << image_width << " " << image_height << "\n255\n";
@@ -1425,11 +1427,11 @@
     }
     ...
     int main() {
-        int image_width = 200;
-        int image_height = 100;
-        int samples_per_pixel = 100;
+        const int image_width = 200;
+        const int image_height = 100;
+        const int samples_per_pixel = 100;
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ C++ highlight
-        int max_depth = 50;
+        const int max_depth = 50;
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ C++
 
         ...
@@ -1897,10 +1899,11 @@
 
     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ C++
     int main() {
-        int image_width = 200;
-        int image_height = 100;
-        int samples_per_pixel = 100;
-        int max_depth = 50;
+        const int image_width = 200;
+        const int image_height = 100;
+        const int samples_per_pixel = 100;
+        const int max_depth = 50;
+
         std::cout << "P3\n" << image_width << " " << image_height << "\n255\n";
 
 

src/InOneWeekend/main.cc

@@ -82,10 +82,10 @@ hittable_list random_scene() {
 
 
 int main() {
-    int image_width = 1200;
-    int image_height = 800;
-    int samples_per_pixel = 10;
-    int max_depth = 50;
+    const int image_width = 1200;
+    const int image_height = 800;
+    const int samples_per_pixel = 10;
+    const int max_depth = 50;
 
     std::cout << "P3\n" << image_width << ' ' << image_height << "\n255\n";
 

src/TheNextWeek/main.cc

@@ -346,15 +346,26 @@ hittable_list final_scene() {
 
 
 int main() {
-    int image_width = 600;
-    int image_height = 600;
-    int samples_per_pixel = 100;
-    int max_depth = 50;
-
-    std::cout << "P3\n" << image_width << ' ' << image_height << "\n255\n";
+    const int image_width = 600;
+    const int image_height = 600;
+    const int samples_per_pixel = 100;
+    const int max_depth = 50;
 
     hittable_list world;
 
+    vec3 lookfrom(278, 278, -800);
+    //vec3 lookfrom(478, 278, -600);
+    //vec3 lookfrom(0, 0, 6);
+    vec3 lookat(278,278,0);
+    //vec3 lookat(0,0,0);
+    vec3 vup(0,1,0);
+    auto dist_to_focus = 10.0;
+    auto aperture = 0.0;
+    auto vfov = 40.0;
+
+    auto aspect_ratio = double(image_width) / image_height;
+    camera cam(lookfrom, lookat, vup, vfov, aspect_ratio, aperture, dist_to_focus, 0.0, 1.0);
+
     switch (0) {
         case 1:
             world = random_scene();
@@ -398,18 +409,8 @@ int main() {
             break;
     }
 
-    vec3 lookfrom(278, 278, -800);
-    //vec3 lookfrom(478, 278, -600);
-    //vec3 lookfrom(0, 0, 6);
-    vec3 lookat(278,278,0);
-    //vec3 lookat(0,0,0);
-    vec3 vup(0,1,0);
-    auto dist_to_focus = 10.0;
-    auto aperture = 0.0;
-    auto vfov = 40.0;
 
-    auto aspect_ratio = double(image_width) / image_height;
-    camera cam(lookfrom, lookat, vup, vfov, aspect_ratio, aperture, dist_to_focus, 0.0, 1.0);
+    std::cout << "P3\n" << image_width << ' ' << image_height << "\n255\n";
 
     for (int j = image_height-1; j >= 0; --j) {
         std::cerr << "\rScanlines remaining: " << j << ' ' << std::flush;

src/TheRestOfYourLife/main.cc

@@ -91,10 +91,10 @@ hittable_list cornell_box(camera& cam, double aspect) {
 
 
 int main() {
-    int image_width = 600;
-    int image_height = 600;
-    int samples_per_pixel = 100;
-    int max_depth = 50;
+    const int image_width = 600;
+    const int image_height = 600;
+    const int samples_per_pixel = 100;
+    const int max_depth = 50;
 
     std::cout << "P3\n" << image_width << ' ' << image_height << "\n255\n";