cozis/ray_tracing
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Add light sampling

Browse Source
This commit is contained in:
cozis
2024-10-04 13:15:02 +02:00
parent a0b554cdb4
commit a3a89d4bc7
3 changed files with 143 additions and 20 deletions
Download Patch File Download Diff File Expand all files Collapse all files
.gitignore
+2 -1
View File
@@ -1 +1,2 @@
*.exe
*.exe
*.exr
reference.py
+85
View File
@@ -0,0 +1,85 @@
"""
# Import the library using the alias "mi"
import mitsuba as mi
# Set the variant of the renderer
mi.set_variant('scalar_rgb')
# Load a scene
scene = mi.load_dict(mi.cornell_box())
# Render the scene
img = mi.render(scene)
# Write the rendered image to an EXR file
mi.Bitmap(img).write('cbox.exr')
"""
import mitsuba as mi
import cv2
import numpy as np
mi.set_variant('scalar_rgb')
# Define a scene with a sphere and a cube
scene_dict = {
'type': 'scene',
'integrator': {
'type': 'path'
},
'sensor': {
'type': 'perspective',
'film': {
'type': 'hdrfilm',
'width': 800,
'height': 600,
},
'sampler': {
'type': 'independent',
'sample_count': 64
},
'to_world': mi.ScalarTransform4f.look_at(
origin=[10, 10, 10], # Camera position
target=[0, 0, 0], # Camera looks at the origin
up=[0, 1, 0] # Up direction for the camera
)
},
'light': {
'type': 'point',
'position': [0, 5, 0],
'intensity': {'type': 'spectrum', 'value': 30.0}
},
'sphere': {
'type': 'sphere',
'center': [0, 0, 0],
'radius': 1,
'bsdf': {
'type': 'diffuse',
'reflectance': {'type': 'rgb', 'value': [0.8, 0.3, 0.3]}
}
},
'cube': {
'type': 'cube',
'to_world': mi.ScalarTransform4f.translate([2, 0, 0]).scale(1),
'bsdf': {
'type': 'diffuse',
'reflectance': {'type': 'rgb', 'value': [0.3, 0.8, 0.3]}
}
},
'floor': {
'type': 'cube',
'to_world': mi.ScalarTransform4f.translate([0, -0.5, 0]).scale([5, 0.01, 5]),
'bsdf': {
'type': 'diffuse',
'reflectance': {'type': 'rgb', 'value': [0.8, 0.8, 0.8]} # Light grey floor
}
}
}
# Load and render the scene
scene = mi.load_dict(scene_dict)
img = mi.render(scene)
# Convert the rendered image to a numpy array
bitmap = mi.Bitmap(img)
image_np = np.array(bitmap.convert(mi.Bitmap.PixelFormat.RGB, mi.Struct.Type.UInt8))
# Display the image using OpenCV
cv2.imshow('Rendered Image', image_np)
cv2.waitKey(0) # Press any key to close the window
cv2.destroyAllWindows()
src/main.c
+56 -19
View File
@@ -553,6 +553,13 @@ HitInfo trace_ray(Ray ray)
}
}
Vector3 origin_of(Object o)
{
if (o.type == OBJECT_SPHERE)
return o.sphere.center;
return combine(o.cube.origin, o.cube.size, 1, 0.5);
}
Cubemap skybox;
Vector3 pixel(float x, float y, float aspect_ratio)
@@ -570,8 +577,6 @@ Vector3 pixel(float x, float y, float aspect_ratio)
Vector3 result = {0, 0, 0};
for (int i = 0; i < 100; i++) {
assert(!isnanv(in_ray.direction));
HitInfo hit = trace_ray(in_ray);
if (hit.object == -1) {
//Vector3 sky_color = sample_cubemap(&skybox, normalize(in_ray.direction));
@@ -581,19 +586,14 @@ Vector3 pixel(float x, float y, float aspect_ratio)
Material material = objects[hit.object].material;
Vector3 reflect_dir = reflect(in_ray.direction, scale(hit.normal, -1));
assert(!isnanv(reflect_dir));
Vector3 rand_dir = random_direction();
assert(!isnanv(rand_dir));
if (dotv(rand_dir, hit.normal) < 0)
rand_dir = scale(rand_dir, -1);
Vector3 out_dir = normalize(combine(rand_dir, reflect_dir, material.roughness, 1));
assert(!isnanv(out_dir));
Ray out_ray = (Ray) { combine(hit.point, out_dir, 1, 0.001), out_dir };
Ray out_ray = { combine(hit.point, out_dir, 1, 0.001), out_dir };
Vector3 diffuse_contrib;
Vector3 emitted_light;
{
float perceptualRoughness = maxf(material.roughness, 0.089);
float roughness = perceptualRoughness * perceptualRoughness;
@@ -615,10 +615,37 @@ Vector3 pixel(float x, float y, float aspect_ratio)
Vector3 specular = scale(F, (D * V) / (4.0 * NoV * NoL + 0.0001));
Vector3 diffuse = mulv(combine((Vector3) {1, 1, 1}, F, 1, -1), scale(material.albedo, 1 - material.metallic));
Vector3 combined = combine(diffuse, specular, 1, 1);
diffuse_contrib = scale(combine(diffuse, specular, 1, 1), NoL);
emitted_light = scale(material.emission_color, material.emission_power);
}
result = combine(result, mulv(contrib, material.emission_color), 1, material.emission_power);
contrib = mulv(contrib, scale(combined, NoL));
bool sampled_light = false;
Vector3 sampled_light_color;
{
for (int j = 0; j < num_objects; j++) {
if (objects[j].material.emission_power == 0 || j == hit.object)
continue;
Vector3 dir_to_light_source = combine(origin_of(objects[j]), hit.point, 1, -1);
// Add some noise based on roughness
Vector3 rand_dir = random_direction();
if (dotv(rand_dir, hit.normal) < 0)
rand_dir = scale(rand_dir, -1);
dir_to_light_source = normalize(combine(rand_dir, dir_to_light_source, material.roughness, 1));
Ray ray_to_light_source = { combine(hit.point, dir_to_light_source, 1, 0.001), dir_to_light_source };
HitInfo hit2 = trace_ray(ray_to_light_source);
if (hit2.object == j) {
sampled_light = true;
sampled_light_color = scale(objects[hit2.object].material.emission_color, objects[hit2.object].material.emission_power);
break;
}
}
}
result = combine(result, mulv(emitted_light, contrib), 1, 1);
contrib = mulv(contrib, diffuse_contrib);
if (sampled_light) {
contrib = scale(contrib, 0.5);
result = combine(result, mulv(sampled_light_color, contrib), 1, 1);
}
in_ray = out_ray;
@@ -812,7 +839,7 @@ int main(void)
.emission_power=0,
.metallic=0,
.reflectance=0,
.roughness=0,
.roughness=1,
.albedo=(Vector3) {1, 1, 1}
},
(Vector3) {0, 0, 0},
@@ -825,7 +852,7 @@ int main(void)
.emission_power=0,
.metallic=0,
.reflectance=0,
.roughness=0,
.roughness=1,
.albedo=(Vector3) {1, 1, 1}
},
(Vector3) {box_w, 0, 0},
@@ -847,8 +874,8 @@ int main(void)
add_object(cube(
(Material) {
.emission_color={1, 1, 1},
.emission_power=2,
.emission_color={0.5, 0.5, 0.5},
.emission_power=1,
.metallic=0,
.reflectance=0,
.roughness=1,
@@ -871,7 +898,7 @@ int main(void)
box_w/3
));
#elif 0
#elif 1
add_object(cube ((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .reflectance=0, .roughness=0, .albedo=(Vector3) {1, 0.3, 0.3}}, (Vector3) {0, 0, 0}, (Vector3) {10, 5, 0.1}));
add_object(cube ((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .reflectance=0, .roughness=0.6, .albedo=(Vector3) {0.3, 1, 0.3}}, (Vector3) {0, 0, 0}, (Vector3) {0.1, 5, 10}));
add_object(cube ((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .reflectance=0, .roughness=1, .albedo=(Vector3) {0.4, 0.3, 0.9}}, (Vector3) {0, -0.1, 0}, (Vector3) {10, 0.1, 10}));
@@ -879,9 +906,19 @@ int main(void)
add_object(cube ((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .reflectance=0, .roughness=0, .albedo=(Vector3) {1, 0, 1}}, (Vector3) {6, 0, 7}, (Vector3) {1, 1, 1}));
add_object(sphere((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .reflectance=0, .roughness=0.5, .albedo=(Vector3) {1, 0.4, 0}}, (Vector3) {3, 1, 3}, 1));
add_object(sphere((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .reflectance=0, .roughness=0, .albedo=(Vector3) {0, 1, 0}}, (Vector3) {5, 1, 3}, 1));
add_object(sphere((Material) {.emission_color={1, 0.4, 0.2}, .emission_power=3, .metallic=0, .reflectance=0, .roughness=1, .albedo=(Vector3) {1, 0.4, 0}}, (Vector3) {3, 5, 3}, 1));
add_object(sphere((Material) {.emission_color={1, 1, 1}, .emission_power=1, .metallic=0, .reflectance=0, .roughness=1, .albedo=(Vector3) {1, 0.4, 0}}, (Vector3) {3, 5, 3}, 1));
#elif 1
// add_object(cube ((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .reflectance=0, .roughness=0, .albedo=(Vector3) {1, 0.3, 0.3}}, (Vector3) {0, 0, 0}, (Vector3) {10, 5, 0.1}));
// add_object(cube ((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .reflectance=0, .roughness=0.6, .albedo=(Vector3) {0.3, 1, 0.3}}, (Vector3) {0, 0, 0}, (Vector3) {0.1, 5, 10}));
add_object(cube ((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .reflectance=0, .roughness=1, .albedo=(Vector3) {0.4, 0.3, 0.9}}, (Vector3) {0, -0.1, 0}, (Vector3) {10, 0.1, 10}));
// add_object(cube ((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .reflectance=0, .roughness=1, .albedo=(Vector3) {1, 0, 0}}, (Vector3) {7, 0, 8}, (Vector3) {1, 1, 1}));
// add_object(cube ((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .reflectance=0, .roughness=0, .albedo=(Vector3) {1, 0, 1}}, (Vector3) {6, 0, 7}, (Vector3) {1, 1, 1}));
// add_object(sphere((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .reflectance=0, .roughness=0.5, .albedo=(Vector3) {1, 0.4, 0}}, (Vector3) {3, 1, 3}, 1));
// add_object(sphere((Material) {.emission_color={0}, .emission_power=0, .metallic=0, .reflectance=0, .roughness=0, .albedo=(Vector3) {0, 1, 0}}, (Vector3) {5, 1, 3}, 1));
add_object(sphere((Material) {.emission_color={1, 1, 1}, .emission_power=1, .metallic=0, .reflectance=0, .roughness=1, .albedo=(Vector3) {1, 0.4, 0}}, (Vector3) {3, 5, 3}, 1));
#endif
{
const char *faces[] = {
[CF_RIGHT] = "assets/skybox/right.jpg",