stuff

Signed-off-by: Slendi <slendi@socopon.com>

src/Types.h

@@ -1,5 +1,7 @@
 #pragma once
 
+#include <cmath>
+
 #include <smath.hpp>
 #include <vk_mem_alloc.h>
 #include <vulkan/vulkan.hpp>
@@ -55,4 +57,39 @@ struct GPUSceneData {
 	smath::Vec4 sunlight_color;
 };
 
+struct Camera {
+	smath::Vec3 position {};
+	smath::Vec3 target { 0, 0, -1 };
+	smath::Vec3 up { 0, 1, 0 };
+	float fovy { smath::deg(70.0f) };
+};
+
+struct PolarCoordinate {
+	float r, theta, phi;
+
+	static PolarCoordinate from_vec3(smath::Vec3 const &v)
+	{
+		PolarCoordinate p;
+		p.r = std::sqrt(v.x() * v.x() + v.y() * v.y() + v.z() * v.z());
+
+		if (p.r == 0.0f) {
+			p.theta = 0.0f;
+			p.phi = 0.0f;
+			return p;
+		}
+
+		p.theta = std::atan2(v.z(), v.x());
+		p.phi = std::acos(v.y() / p.r);
+		return p;
+	}
+
+	smath::Vec3 to_vec3() const
+	{
+		float sin_phi = std::sin(phi);
+
+		return smath::Vec3 { r * sin_phi * std::cos(theta), r * std::cos(phi),
+			r * sin_phi * std::sin(theta) };
+	}
+};
+
 } // namespace Lunar