Unfinished business

src/xyz/marsavic/gfxlab/graphics3d/raytracers/RayTracer.java

@@ -22,8 +22,12 @@ public abstract class RayTracer implements ColorFunctionT {
 	
 	@Override
 	public Color at(double t, Vector p) {
-		Ray ray = Ray.pd(Vec3.xyz(0, 0, -2.6), Vec3.zp(1.6, p));
+		Ray ray = Ray.pd(Vec3.xyz(0, 0, -15), Vec3.zp(1.6, p));
 		return sample(ray);
 	}
-	
+//	@Override
+//	public Color at(double t, Vector p) {
+//		Ray ray = Ray.pd(Vec3.xyz(0, 20, -20), Vec3.xyz(0, -1, 1).add(Vec3.xyz(p.x(), p.y(), p.y())));
+//		return sample(ray);
+//	}
 }

src/xyz/marsavic/gfxlab/graphics3d/solids/Cylinder.java

@@ -0,0 +1,107 @@
+package xyz.marsavic.gfxlab.graphics3d.solids;
+
+import xyz.marsavic.functions.interfaces.F1;
+import xyz.marsavic.geometry.Vector;
+import xyz.marsavic.gfxlab.Vec3;
+import xyz.marsavic.gfxlab.graphics3d.Hit;
+import xyz.marsavic.gfxlab.graphics3d.Material;
+import xyz.marsavic.gfxlab.graphics3d.Ray;
+import xyz.marsavic.gfxlab.graphics3d.Solid;
+import xyz.marsavic.utils.Numeric;
+
+public class Cylinder implements Solid {
+
+    private final Vec3 p;
+    private final double r;
+    private final Vec3 d; // directional vector, for a finite cylinder it also represents the height
+    private final F1<Material, Vector> mapMaterial;
+
+    // transient
+    private final double rSqr;
+    private final boolean finite;
+
+
+    private Cylinder(Vec3 p, double r, Vec3 d, F1<Material, Vector> mapMaterial, boolean finite) {
+        this.p = p;
+        this.r = r;
+        this.d = d;
+        rSqr = r * r;
+        this.mapMaterial = mapMaterial;
+        this.finite = finite;
+
+    }
+
+
+    public static Cylinder prdi(Vec3 p, double r, Vec3 d, F1<Material, Vector> mapMaterial) {
+        return new Cylinder(p, r, d, mapMaterial, false);
+    }
+
+    public static Cylinder prd(Vec3 p, double r, Vec3 d, F1<Material, Vector> mapMaterial) {
+        return new Cylinder(p, r, d, mapMaterial, true);
+    }
+
+    public static Cylinder crd(Vec3 c, double r, Vec3 d, F1<Material, Vector> mapMaterial) {
+        return new Cylinder(c.sub(d.div(2)), r, d, mapMaterial, true);
+    }
+
+    public Vec3 c() {
+        return p.add(d.div(2));
+    }
+
+    public Vec3 p() { return p; }
+    public double r() {
+        return r;
+    }
+    public Vec3 d() {
+        return d;
+    }
+
+    @Override
+    public Cylinder.HitCylinder firstHit(Ray ray, double afterTime) {
+        Vec3 e = c().sub(ray.p()); // Vector from the ray origin to the Cylinder start point
+
+        double dSqr = ray.d().lengthSquared();
+        double l = e.dot(ray.d()) / dSqr;
+        double mSqr = l * l - (e.lengthSquared() - rSqr) / dSqr;
+
+        if (mSqr > 0) {
+            double m = Math.sqrt(mSqr);
+            if (l - m > afterTime) return new Cylinder.HitCylinder(ray, l - m);
+            if (l + m > afterTime) return new Cylinder.HitCylinder(ray, l + m);
+        }
+        return null;
+    }
+
+
+    class HitCylinder extends Hit.RayT {
+
+        protected HitCylinder(Ray ray, double t) {
+            super(ray, t);
+        }
+
+        @Override
+        public Vec3 n() {
+            return ray().at(t()).sub(c());
+        }
+
+        @Override
+        public Material material() {
+            return Cylinder.this.mapMaterial.at(uv());
+        }
+
+        @Override
+        public Vector uv() {
+            Vec3 n = n();
+            return Vector.xy(
+                    Numeric.atan2T(n.z(), n.x()),
+                    -2 * Numeric.asinT(n.y() / r) + 0.5
+            );
+        }
+
+        @Override
+        public Vec3 n_() {
+            return n().div(r);
+        }
+
+    }
+}