5 files changed, 35 insertions, 25 deletions

diff --git a/include/color.hpp b/include/color.hpp
index 34f739a..f300e76 100644
--- a/include/color.hpp
+++ b/include/color.hpp
@@ -5,6 +5,6 @@
 
 #include "vec3.hpp"
 
-void write_color(std::ostream& out, const color& pixel_color, uint32_t samples_per_pixel);
+void write_color(std::ostream& out, const color& pixel_color);
 
 #endif // !__COLOR_HPP_
diff --git a/include/vk-renderer.hpp b/include/vk-renderer.hpp
index ca3e182..b1f8d3f 100644
--- a/include/vk-renderer.hpp
+++ b/include/vk-renderer.hpp
@@ -11,10 +11,12 @@ struct input_data {
     color ground_color;
     vec3 camera_pos;
 
+    uint32_t samples_per_pixel;
     float viewport_width;
     float viewport_height;
     float proj_plane_distance;
-    float pad;
+
+    float random_numbers[200];
 
     struct sphere {
         vec3 position;
diff --git a/shaders/compute.comp b/shaders/compute.comp
index b9c165e..861da63 100644
--- a/shaders/compute.comp
+++ b/shaders/compute.comp
@@ -15,25 +15,27 @@ struct sphere {
     float radius;
 };
 
-vec3 at(ray r, float t) {
-    return r.origin + r.direction * t;
-}
-
 layout(set = 0, binding = 0) buffer Inputs {
     vec4 sky_color;
     vec4 ground_color;
     vec4 camera_pos;
 
+    uint samples_per_pixel;
     float viewport_width;
     float viewport_height;
     float proj_plane_distance;
-    float padding;
+
+    float[200] random_numbers;
 
     sphere s;
 
     vec4[] image;
 };
 
+vec3 at(ray r, float t) {
+    return r.origin + r.direction * t;
+}
+
 bool hit_sphere(ray r, out hit_info info) {
     // Vector from the ray origin to sphere position
     vec3 origin_center = r.origin - s.position.xyz;
@@ -65,20 +67,26 @@ void main() {
     uint height = gl_NumWorkGroups.y;
 
     vec2 uv = vec2(float(x) / (width - 1), 1.0 - (float(y) / (height - 1)));
-
     vec3 first = camera_pos.xyz - vec3(viewport_width / 2.0, viewport_height / 2.0, proj_plane_distance);
-    vec3 proj_plane_pos = first + vec3(uv.x * viewport_width, uv.y * viewport_height, 0.0);
 
-    ray r = ray(camera_pos.xyz, proj_plane_pos - camera_pos.xyz);
-    hit_info info;
+    image[y * width + x] = vec4(0.0);
+
+    for (uint sample_index = 0; sample_index < samples_per_pixel; sample_index++) {
+        vec2 jittered_uvs = uv + vec2(random_numbers[sample_index * 2] / (width - 1), random_numbers[sample_index * 2 + 1] / (height - 1));
+        vec3 proj_plane_pos = first + vec3(jittered_uvs.x * viewport_width, jittered_uvs.y * viewport_height, 0.0);
+
+        ray r = ray(camera_pos.xyz, proj_plane_pos - camera_pos.xyz);
+        hit_info info;
 
-    if (hit_sphere(r, info)) {
-        vec3 hit_normal = normalize(info.normal);
-        hit_normal = (hit_normal + 1.0) * 0.5;
+        if (hit_sphere(r, info)) {
+            vec3 hit_normal = normalize(info.normal);
+            hit_normal = (hit_normal + 1.0) * 0.5;
 
-        image[y * width + x] = vec4(hit_normal, 0.0);
-        return;
+            image[y * width + x] += vec4(hit_normal, 0.0);
+        } else {
+            image[y * width + x] += mix(ground_color, sky_color, uv.y);
+        }
     }
 
-    image[y * width + x] = mix(ground_color, sky_color, uv.y);
+    image[y * width + x] /= samples_per_pixel;
 }
diff --git a/src/color.cpp b/src/color.cpp
index c1036e0..33351a8 100644
--- a/src/color.cpp
+++ b/src/color.cpp
@@ -1,16 +1,11 @@
 #include "color.hpp"
 #include "rt.hpp"
 
-void write_color(std::ostream& out, const color& pixel_color, uint32_t samples_per_pixel) {
+void write_color(std::ostream& out, const color& pixel_color) {
     auto r = pixel_color.x;
     auto g = pixel_color.y;
     auto b = pixel_color.z;
 
-    // auto scale = 1.0 / samples_per_pixel;
-    // r = sqrt(r * scale);
-    // g = sqrt(g * scale);
-    // b = sqrt(b * scale);
-
     out << static_cast<uint32_t>(256.0 * clamp(r, 0.0, 0.999)) << ' '
         << static_cast<uint32_t>(256.0 * clamp(g, 0.0, 0.999)) << ' '
         << static_cast<uint32_t>(256.0 * clamp(b, 0.0, 0.999)) << std::endl;
diff --git a/src/main.cpp b/src/main.cpp
index b769dd3..8811c78 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -85,7 +85,7 @@ int main() {
     const float aspect_ratio = 1.0 / 1.0;
     const size_t width = 400;
     const size_t height = width / aspect_ratio;
-    const uint32_t samples_per_pixel = 1;
+    const uint32_t samples_per_pixel = 100;
     const uint32_t max_depth = 100;
 
     // const vec3 camera_position{ 13.0, 2.0, 3.0 };
@@ -98,6 +98,7 @@ int main() {
         .sky_color = sky_color,
         .ground_color = ground_color,
         .camera_pos = camera_position,
+        .samples_per_pixel = samples_per_pixel,
         .viewport_width = 2.f * aspect_ratio,
         .viewport_height = 2.f,
         .proj_plane_distance = 1.f,
@@ -105,6 +106,10 @@ int main() {
         // .sphere = { { 0.f, -100.5f, -1.f }, 100.f },
     };
 
+    for (size_t rand_number_index = 0; rand_number_index < samples_per_pixel * 2; rand_number_index++) {
+        inputs.random_numbers[rand_number_index] = randd();
+    }
+
     // World hittable objects
     hittable_list world = random_scene();
 
@@ -120,7 +125,7 @@ int main() {
     //-------------------------
     auto output_image = renderer.output_image();
     for (size_t index = 0; index < height * width; index++) {
-        write_color(std::cout, output_image[index], samples_per_pixel);
+        write_color(std::cout, output_image[index]);
     }
 
     std::cerr << "Done !" << std::endl;