Implemented light functions

RayTracer/shape/CirclePlane.cpp

+#define _USE_MATH_DEFINES
+
 #include "CirclePlane.h"
 
+#include "../tools/Random.h"
+#include "math.h"
+
 namespace shapes {
 CirclePlane::CirclePlane(float radius,
                          const std::shared_ptr<material::Material>& material)
@@ -31,4 +36,20 @@ util::AxisAlignedBoundingBox CirclePlane::bounds() const {
 	return util::AxisAlignedBoundingBox(util::Vec3(-radius, 0, -radius),
 	                                    util::Vec3(radius, 0, radius));
 }
+// THIS IS COPIED AND BAD TODO!!!!
+util::SurfacePoint CirclePlane::sampleLight() const {
+	float u[2] = {(float)util::dis0to1(util::gen),
+	              (float)util::dis0to1(util::gen)};
+	float r = std::sqrt(u[0]) * radius;
+	float theta = 2 * M_PI * u[1];
+	return util::SurfacePoint(
+	    util::Vec3(r * std::cos(theta), 0, r * std::sin(theta)),
+	    util::Vec3(0, -1, 0), material);
+}
+util::Vec3 CirclePlane::calculateLightEmission(const util::SurfacePoint& p,
+                                               const util::Vec3& d) const {
+	// Diffus ist hier im dot-product eingebettet
+	return p.albedo() * (p.emission() * util::dot(p.normal(), d.normalize())) /
+	       std::pow(d.length(), 2);
+}
 }  // namespace shapes

RayTracer/shape/CirclePlane.h

 #pragma once
 
+#include "Light.h"
 #include "Shape.h"
 
 namespace shapes {
-class CirclePlane : public Shape {
+class CirclePlane : public Light, public Shape {
    public:
 	CirclePlane(float radius,
 	            const std::shared_ptr<material::Material>& material);
 	std::optional<cam::Hit> intersect(const cam::Ray& r) const override;
 	util::AxisAlignedBoundingBox bounds() const override;
 
+	util::SurfacePoint sampleLight() const override;
+	util::Vec3 calculateLightEmission(const util::SurfacePoint& p,
+	                                  const util::Vec3& d) const override;
+
    private:
 	std::shared_ptr<material::Material> material;
 	const float radius;