added more example scene and oren-nayar diffuse shading

res/head.mtl

@@ -0,0 +1,32 @@
+# Blender 3.4.1 MTL File: 'None'
+# www.blender.org
+
+newmtl light
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.800000 0.800000 0.800000
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.450000
+d 1.000000
+illum 2
+
+newmtl light_blue
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.800000 0.800000 0.800000
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.450000
+d 1.000000
+illum 2
+
+newmtl white
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.800000 0.800000 0.800000
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.450000
+d 1.000000
+illum 2

res/light_box.mtl

@@ -0,0 +1,42 @@
+# Blender 3.4.1 MTL File: 'None'
+# www.blender.org
+
+newmtl light
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.800000 0.800000 0.800000
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.450000
+d 1.000000
+illum 2
+
+newmtl light_green
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.800000 0.800000 0.800000
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.450000
+d 1.000000
+illum 2
+
+newmtl light_red
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.800000 0.800000 0.800000
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.450000
+d 1.000000
+illum 2
+
+newmtl white
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.800000 0.800000 0.800000
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.450000
+d 1.000000
+illum 2

res/plane.mtl

@@ -0,0 +1,42 @@
+# Blender 3.4.1 MTL File: 'None'
+# www.blender.org
+
+newmtl light_blue
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.800000 0.800000 0.800000
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.450000
+d 1.000000
+illum 2
+
+newmtl light_green
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.800000 0.800000 0.800000
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.450000
+d 1.000000
+illum 2
+
+newmtl light_red
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.800000 0.800000 0.800000
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.450000
+d 1.000000
+illum 2
+
+newmtl white
+Ns 250.000000
+Ka 1.000000 1.000000 1.000000
+Kd 0.800000 0.800000 0.800000
+Ks 0.500000 0.500000 0.500000
+Ke 0.000000 0.000000 0.000000
+Ni 1.450000
+d 1.000000
+illum 2

src/shader/composite/final.frag

@@ -24,7 +24,7 @@ void main() {
 
     vec3 color = texture(image, uv).rgb;
 
-    color = smart_de_noise(image, uv, 5.0, 1.0, 0.400).rgb;
+    color = smart_de_noise(image, uv, 5.0, 1.0, 0.200).rgb;
 
     color = reinhard_jodie(color);
 

src/shader/pathtracing/camera.rs

@@ -17,8 +17,8 @@ impl Camera {
             front: Vector3::new(0.0, 0.0, -1.0),
             left: Vector3::new(1.0, 0.0, 0.0),
             up: Vector3::new(0.0, -1.0, 0.0),
-            pos: Vector3::new(0.0, 1.0, 9.0),
+            pos: Vector3::new(0.0, 0.0, 9.0),
-            fov: 90.0f32
+            fov: 65.0f32
         }
     }
 

src/shader/pathtracing/mod.rs

@@ -36,10 +36,10 @@ lazy_static! {
         emission: Padded::from([0.0, 0.0, 0.0]),
         specular_color: [0.0, 0.0, 0.0],
         roughness: 1.0,
+        specular: 0.0,
         transmission: 0.0,
         ior: 1.0,
         metallic: false as u32,
-        __padding: 0
     };
 }
 
@@ -51,10 +51,21 @@ fn add_default_materials() {
         emission: Padded::from([0.0, 0.0, 0.0]),
         specular_color: [0.0, 0.0, 0.0],
         roughness: 1.0,
+        specular: 0.0,
+        transmission: 0.0,
+        ior: 1.0,
+        metallic: false as u32,
+    });
+
+    material_collection.insert(String::from("glossy"), cs::Material {
+        albedo: Padded::from([1.0, 1.0, 1.0]),
+        emission: Padded::from([0.0, 0.0, 0.0]),
+        specular_color: [0.0, 0.0, 0.0],
+        roughness: 0.0,
+        specular: 0.8,
         transmission: 0.0,
         ior: 1.0,
         metallic: false as u32,
-        __padding: 0
     });
 
     material_collection.insert(String::from("red"), cs::Material {
@@ -62,10 +73,10 @@ fn add_default_materials() {
         emission: Padded::from([0.0, 0.0, 0.0]),
         specular_color: [0.0, 0.0, 0.0],
         roughness: 1.0,
+        specular: 0.0,
         transmission: 0.0,
         ior: 1.0,
         metallic: false as u32,
-        __padding: 0
     });
 
     material_collection.insert(String::from("green"), cs::Material {
@@ -73,10 +84,10 @@ fn add_default_materials() {
         emission: Padded::from([0.0, 0.0, 0.0]),
         specular_color: [0.0, 0.0, 0.0],
         roughness: 1.0,
+        specular: 0.0,
         transmission: 0.0,
         ior: 1.0,
         metallic: false as u32,
-        __padding: 0
     });
 
     material_collection.insert(String::from("glass"), cs::Material {
@@ -84,10 +95,10 @@ fn add_default_materials() {
         emission: Padded::from([0.0, 0.0, 0.0]),
         specular_color: [0.0, 0.0, 0.0],
         roughness: 1.5,
+        specular: 0.0,
         transmission: 1.0,
         ior: 1.0,
         metallic: false as u32,
-        __padding: 0
     });
 
     material_collection.insert(String::from("light"), cs::Material {
@@ -95,10 +106,10 @@ fn add_default_materials() {
         emission: Padded::from([1.0, 1.0, 1.0]),
         specular_color: [0.0, 0.0, 0.0],
         roughness: 1.5,
+        specular: 0.0,
         transmission: 0.0,
         ior: 0.0,
         metallic: false as u32,
-        __padding: 0
     });
 
     material_collection.insert(String::from("light_blue"), cs::Material {
@@ -106,10 +117,10 @@ fn add_default_materials() {
         emission: Padded::from([0.3, 0.3, 1.0]),
         specular_color: [0.0, 0.0, 0.0],
         roughness: 1.5,
+        specular: 0.0,
         transmission: 0.0,
         ior: 0.0,
         metallic: false as u32,
-        __padding: 0
     });
 
     material_collection.insert(String::from("light_red"), cs::Material {
@@ -117,10 +128,10 @@ fn add_default_materials() {
         emission: Padded::from([1.0, 0.3, 0.3]),
         specular_color: [0.0, 0.0, 0.0],
         roughness: 1.5,
+        specular: 0.0,
         transmission: 0.0,
         ior: 0.0,
         metallic: false as u32,
-        __padding: 0
     });
 
     material_collection.insert(String::from("light_green"), cs::Material {
@@ -128,10 +139,10 @@ fn add_default_materials() {
         emission: Padded::from([0.3, 1.0, 0.3]),
         specular_color: [0.0, 0.0, 0.0],
         roughness: 1.5,
+        specular: 0.0,
         transmission: 0.0,
         ior: 0.0,
         metallic: false as u32,
-        __padding: 0
     });
 }
 
@@ -291,7 +302,7 @@ fn create_image(memory_allocator: &StandardMemoryAllocator, queue: &Arc<Queue>,
 }
 
 fn load_example_scene() -> (Vec<[f32; 4]>, Vec<u32>, Vec<cs::Material>) {
-    let (mut models, materials) = tobj::load_obj("res/example-scene.obj", &tobj::GPU_LOAD_OPTIONS).expect("unable to load scene from obj");
+    let (mut models, materials) = tobj::load_obj("res/head.obj", &tobj::GPU_LOAD_OPTIONS).expect("unable to load scene from obj");
 
     // allocate some host memory
     let mut vertices:Vec<[f32; 4]> = vec![];
@@ -336,7 +347,7 @@ fn create_gpu_buffer(vertices: &Vec<[f32; 4]>, indices: &Vec<u32>, materials: &V
             ..Default::default()
         },
         AllocationCreateInfo {
-            usage: MemoryUsage::DeviceOnly,
+            usage: MemoryUsage::Upload,
             ..Default::default()
         },
         vertices.clone(),
@@ -349,7 +360,7 @@ fn create_gpu_buffer(vertices: &Vec<[f32; 4]>, indices: &Vec<u32>, materials: &V
             ..Default::default()
         },
         AllocationCreateInfo {
-            usage: MemoryUsage::DeviceOnly,
+            usage: MemoryUsage::Upload,
             ..Default::default()
         },
         indices.clone(),
@@ -362,7 +373,7 @@ fn create_gpu_buffer(vertices: &Vec<[f32; 4]>, indices: &Vec<u32>, materials: &V
             ..Default::default()
         },
         AllocationCreateInfo {
-            usage: MemoryUsage::DeviceOnly,
+            usage: MemoryUsage::Upload,
             ..Default::default()
         },
         materials.clone(),

src/shader/pathtracing/pathtracer.comp

@@ -27,6 +27,22 @@ uint get_pixel_index() {
     return gl_GlobalInvocationID.y * uint(program_metadata.resolution.x) + gl_GlobalInvocationID.x;
 }
 
+// from: https://github.com/glslify/glsl-diffuse-oren-nayar/blob/master/index.glsl
+vec3 oren_nayar_diffuse(in vec3 lightDirection, in vec3 viewDirection, in vec3 surfaceNormal, in float roughness, in vec3 albedo) {
+    float LdotV = dot(lightDirection, viewDirection);
+    float NdotL = dot(lightDirection, surfaceNormal);
+    float NdotV = dot(surfaceNormal, viewDirection);
+
+    float s = LdotV - NdotL * NdotV;
+    float t = mix(1.0, max(NdotL, NdotV), step(0.0, s));
+
+    float sigma2 = roughness * roughness;
+    vec3 A = 1.0 + sigma2 * (albedo / (sigma2 + 0.13) + 0.5 / (sigma2 + 0.33));
+    float B = 0.45 * sigma2 / (sigma2 + 0.09);
+
+    return albedo * max(0.0, NdotL) * (A + B * s / t) / PI;
+}
+
 vec3 trace_direct(in Ray ray) {
     vec3 color = vec3(0);
     vec3 throughput = vec3(1);
@@ -42,12 +58,23 @@ vec3 trace_direct(in Ray ray) {
 
         Material material = materials[hit.material_index];
 
-        color += material.emission * 64.0 * throughput * pdf;
+        color += material.emission * 256.0 * throughput * pdf;
 
-        throughput *= material.albedo;
+        float fresnel = abs(dot(ray.direction, hit.normal));
 
-        ray.origin = ray.origin + ray.direction * hit.depth;
+        if (random() * material.specular > fresnel) {
-        ray.direction = generate_brdf_ray_direction(hit.normal, ray.direction, 1.0);
+            // reflection ray
+            ray.origin = ray.origin + ray.direction * hit.depth;
+            ray.direction = generate_brdf_ray_direction(hit.normal, ray.direction, material.roughness);
+        } else {
+            vec3 incident = ray.direction;
+
+            // diffuse ray
+            ray.origin = ray.origin + ray.direction * hit.depth;
+            ray.direction = generate_brdf_ray_direction(hit.normal, ray.direction, 1.0);
+
+            throughput *= oren_nayar_diffuse(ray.direction, incident, hit.normal, material.roughness, material.albedo);
+        }
     }
 
     return color;

src/shader/pathtracing/raytracing/raytracing.glsl

@@ -30,16 +30,13 @@ struct Material {
     vec3 specular_color;
     // roughtness of the microfacets
     float roughness;
+    float specular;
     // index of refraction (exclusive to metalic)
     float ior;
     // how transmissive the surface is (exclusive to metalic)
     float transmission;
     // whether the surface is metalic or not (exclusive to ior and transmission)
     bool metallic;
-    // extra padding required for vulkano not properly padding the structs in the buffer
-    // the size of the useble data is 60 bytes, GLSL will add 4 additional bytes, to round up to 64.
-    // for compatibility I added the padding manually
-    bool __padding;
 };
 
 layout(set = 0, binding = 3) buffer VertexBuffer {
@@ -74,7 +71,7 @@ vec3 intersect_triangle(in Ray ray, in vec3 v0, in vec3 v1, in vec3 v2, out vec3
 
     // test if the intersection lies outside of the triangle by checking the bounds of the barycentric coordinates
     // also perform backface culling
-    if(u < 0.0 || v < 0.0 || (u + v) > 1.0 || d > 0.0)
+    if(u < 0.0 || v < 0.0 || (u + v) > 1.0)
         t = -1.0;
 
     return vec3(t, u, v);