jonah/raytracing
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

add shading according to normal vector

Browse Source
This commit is contained in:
jbb01 2024-08-03 01:44:27 +02:00
parent 590054a046
commit 14fd1d73fc
5 changed files with 39 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
src/main/java/eu/jonahbauer/raytracing/render/Scene.java
View File

@ -4,7 +4,9 @@ import eu.jonahbauer.raytracing.math.Ray;
import eu.jonahbauer.raytracing.shape.Shape;
import org.jetbrains.annotations.NotNull;
import java.util.Comparator;
import java.util.List;
import java.util.Optional;
public record Scene(@NotNull List<@NotNull Shape> shapes) {
@ -25,11 +27,17 @@ public record Scene(@NotNull List<@NotNull Shape> shapes) {
var ray = pixel.ray();
var result = shapes.stream()
.mapToDouble(shape -> shape.hit(ray))
.filter(Double::isFinite)
.min();
.map(shape -> shape.hit(ray))
.flatMap(Optional::stream)
.min(Comparator.naturalOrder());
if (result.isPresent()) {
image.set(x, y, Color.RED);
var normal = result.get().normal();
image.set(x, y, new Color(
0.5 * (normal.x() + 1),
0.5 * (normal.y() + 1),
0.5 * (normal.z() + 1)
));
} else {
image.set(x, y, getSkyboxColor(ray));
}

16
src/main/java/eu/jonahbauer/raytracing/shape/HitResult.java Normal file
View File

@ -0,0 +1,16 @@
package eu.jonahbauer.raytracing.shape;
import eu.jonahbauer.raytracing.math.Vec3;
import org.jetbrains.annotations.NotNull;
public record HitResult(double t, @NotNull Vec3 normal) implements Comparable<HitResult> {
public HitResult {
if (t < 0 || !Double.isFinite(t)) throw new IllegalArgumentException("t must be non-negative");
normal = normal.unit();
}
@Override
public int compareTo(@NotNull HitResult o) {
return Double.compare(t, o.t);
}
}

4
src/main/java/eu/jonahbauer/raytracing/shape/Shape.java
View File

@ -3,6 +3,8 @@ package eu.jonahbauer.raytracing.shape;
import eu.jonahbauer.raytracing.math.Ray;
import org.jetbrains.annotations.NotNull;
import java.util.Optional;
public sealed interface Shape permits Sphere {
/**
@ -10,5 +12,5 @@ public sealed interface Shape permits Sphere {
* the ray origin, or <code>Double.NaN</code> if the ray does not intersect this shape}
* @param ray a ray
*/
double hit(@NotNull Ray ray);
@NotNull Optional<HitResult> hit(@NotNull Ray ray);
}

9
src/main/java/eu/jonahbauer/raytracing/shape/Sphere.java
View File

@ -5,6 +5,7 @@ import eu.jonahbauer.raytracing.math.Vec3;
import org.jetbrains.annotations.NotNull;
import java.util.Objects;
import java.util.Optional;
public record Sphere(@NotNull Vec3 center, double radius) implements Shape {
public static final @NotNull Sphere UNIT = new Sphere(Vec3.ZERO, 1.0);
@ -19,7 +20,7 @@ public record Sphere(@NotNull Vec3 center, double radius) implements Shape {
}
@Override
public double hit(@NotNull Ray ray) {
public @NotNull Optional<HitResult> hit(@NotNull Ray ray) {
var oc = ray.origin().minus(center());
var a = ray.direction().squared();
@ -27,14 +28,14 @@ public record Sphere(@NotNull Vec3 center, double radius) implements Shape {
var c = oc.squared() - radius * radius;
var discriminant = b * b - 4 * a * c;
if (discriminant < 0) return Double.NaN;
if (discriminant < 0) return Optional.empty();
var sd = Math.sqrt(discriminant);
double t = (- b - sd) / (2 * a);
if (t < 0) t = (-b + sd) / (2 * a);
if (t < 0) t = Double.NaN;
return t;
if (t < 0) return Optional.empty();
return Optional.of(new HitResult(t, ray.at(t).minus(center)));
}
public @NotNull Sphere withCenter(@NotNull Vec3 center) {

6
src/test/java/eu/jonahbauer/raytracing/shape/SphereTest.java
View File

@ -18,8 +18,8 @@ class SphereTest {
var direction = new Vec3(-1, -1, -1);
var ray = new Ray(origin, direction);
var t = sphere.hit(ray);
assertFalse(Double.isNaN(t));
assertEquals(center.plus(new Vec3(1, 1, 1).unit().times(radius)), ray.at(t));
var result = sphere.hit(ray);
assertFalse(result.isEmpty());
assertEquals(center.plus(new Vec3(1, 1, 1).unit().times(radius)), ray.at(result.get().t()));
}
}