diff options
| -rw-r--r-- | include/vk-renderer.hpp | 6 | ||||
| -rw-r--r-- | shaders/compute.comp | 44 | ||||
| -rw-r--r-- | src/main.cpp | 9 |
3 files changed, 48 insertions, 11 deletions
diff --git a/include/vk-renderer.hpp b/include/vk-renderer.hpp index afd5019..2e996c8 100644 --- a/include/vk-renderer.hpp +++ b/include/vk-renderer.hpp @@ -9,6 +9,7 @@ enum MATERIAL_TYPE: uint32_t { LAMBERTIAN, METAL, + DIELECTRIC, }; struct input_data { @@ -29,12 +30,13 @@ struct input_data { struct material { color albedo; float fuzz; + float ior; uint32_t type; - uint32_t padding[2]; + uint32_t padding; } material; float radius; float padding[3]; - } spheres[4]; + } spheres[5]; uint32_t max_bounce; float padding[3]; diff --git a/shaders/compute.comp b/shaders/compute.comp index 7763538..92fae9d 100644 --- a/shaders/compute.comp +++ b/shaders/compute.comp @@ -3,11 +3,16 @@ struct ray { vec3 direction; }; +const uint LAMBERTIAN_MATERIAL = 0; +const uint METAL_MATERIAL = 1; +const uint DIELECTRIC_MATERIAL = 2; + struct material { vec4 albedo; float fuzz; + float ior; uint type; - uint[2] padding; + uint padding; }; struct hit_info { @@ -39,7 +44,7 @@ layout(set = 0, binding = 0) buffer Inputs { vec4[1000] random_in_sphere; - sphere[4] spheres; + sphere[5] spheres; uint max_bounce; float [3] padding; @@ -100,7 +105,7 @@ bool hit_spheres(ray r, float min_t, float max_t, out hit_info info) { float closest_t = max_t; hit_info temp_info; bool hit = false; - for (uint sphere_index = 0; sphere_index < 4; sphere_index++) { + for (uint sphere_index = 0; sphere_index < 5; sphere_index++) { if (hit_sphere(spheres[sphere_index], r, min_t, closest_t, temp_info)) { info = temp_info; closest_t = temp_info.t; @@ -130,6 +135,34 @@ bool metal_scattering(material mat, ray incident, vec2 seed, hit_info info, out return (dot(scattered.direction, info.normal) > 0.0); } +float reflectance(float cosine, float eta) { + // Use Schlick's approximation for reflectance. + float r0 = (1 - eta) / (1 + eta); + r0 = r0 * r0; + return r0 + (1 - r0) * pow((1 - cosine), 5); +} + +bool dielectric_scattering(material mat, ray incident, vec2 seed, hit_info info, out vec4 attenuation, out ray scattered) { + attenuation = vec4(1.0); + + vec3 unit_dir = normalize(incident.direction); + float cos_theta = min(dot(-unit_dir, info.normal), 1.0); + float sin_theta = sqrt(1.0 - cos_theta*cos_theta); + + float eta = info.front_face ? 1.0 / mat.ior : mat.ior; + vec3 direction; + + if (eta * sin_theta > 1.0 || reflectance(cos_theta, eta) > rand(seed)) { + direction = reflect(unit_dir, info.normal); + } else { + direction = refract(unit_dir, info.normal, eta); + } + + scattered = ray(info.point, direction); + + return true; +} + vec4 ray_color(ray r, uint sample_index) { hit_info info; uint bounces = 0; @@ -140,8 +173,9 @@ vec4 ray_color(ray r, uint sample_index) { vec2 seed = vec2(info.point.x * sample_index, info.point.y * bounces) * gl_GlobalInvocationID.xy; ray scattered; vec4 attenuation; - if (info.mat.type == 0 && lambertian_scattering(info.mat, current_ray, seed, info, attenuation, scattered) || - info.mat.type == 1 && metal_scattering(info.mat, current_ray, seed, info, attenuation, scattered)) { + if (info.mat.type == LAMBERTIAN_MATERIAL && lambertian_scattering(info.mat, current_ray, seed, info, attenuation, scattered) || + info.mat.type == METAL_MATERIAL && metal_scattering(info.mat, current_ray, seed, info, attenuation, scattered) || + info.mat.type == DIELECTRIC_MATERIAL && dielectric_scattering(info.mat, current_ray, seed, info, attenuation, scattered)) { final_color *= attenuation; current_ray = scattered; } else { diff --git a/src/main.cpp b/src/main.cpp index 7ba2b47..66b1f6a 100644 --- a/src/main.cpp +++ b/src/main.cpp @@ -103,10 +103,11 @@ int main() { .viewport_height = 2.f, .proj_plane_distance = 1.f, .spheres = { - { { -1.f, 0.f, -1.f }, { { 0.8f, 0.8f, 0.8f }, 0.3, MATERIAL_TYPE::METAL }, 0.5f }, - { { 0.f, 0.f, -1.f }, { { 0.7f, 0.3f, 0.3f }, MATERIAL_TYPE::LAMBERTIAN }, 0.5f }, - { { 1.f, 0.f, -1.f }, { { 0.8f, 0.6f, 0.2f }, 1.0, MATERIAL_TYPE::METAL }, 0.5f }, - { { 0.f, -100.5f, -1.f }, { { 0.8f, 0.8f, 0.f }, MATERIAL_TYPE::LAMBERTIAN }, 100.f } + { { -1.f, 0.f, -1.f }, { { 0.8f, 0.8f, 0.8f }, 0.3, 1.5, MATERIAL_TYPE::DIELECTRIC }, 0.5f }, + { { -1.f, 0.f, -1.f }, { { 0.8f, 0.8f, 0.8f }, 0.3, 1.5, MATERIAL_TYPE::DIELECTRIC }, -0.4f }, + { { 0.f, 0.f, -1.f }, { { 0.7f, 0.3f, 0.3f }, 0.0, 1.5, MATERIAL_TYPE::DIELECTRIC }, 0.5f }, + { { 1.f, 0.f, -1.f }, { { 0.8f, 0.6f, 0.2f }, 1.0, 0.0, MATERIAL_TYPE::METAL }, 0.5f }, + { { 0.f, -100.5f, -1.f }, { { 0.8f, 0.8f, 0.f }, 0.0, 0.0, MATERIAL_TYPE::LAMBERTIAN }, 100.f } }, .max_bounce = max_depth, }; |