protot/src/modules/RenderModule.h

#pragma once

#include <cstdint>

#include <map>
#include <vector>

#include "math_types.h"

#include "Globals.h"

struct Camera {
	Vector3f eye;
	Vector3f poi;
	Vector3f up;

	float near;
	float far;
	float fov;
	bool orthographic;
	float width;
	float height;

	Matrix44f mtxProj;
	Matrix44f mtxView;

	Camera() :
		eye {5.f, 4.f, 5.f},
		poi {0.f, 2.f, 0.f},
		up  {0.f, 1.f, 0.f},
		near (0.1f),
		far (150.f),
		fov (60.f),
		orthographic (false),
		width (-1.f),
		height (-1.f),

		mtxProj (
			1.f, 0.f, 0.f, 0.f,
			0.f, 1.f, 0.f, 0.f,
			0.f, 0.f, 1.f, 0.f,
			0.f, 0.f, 0.f, 1.f),
		mtxView (
			1.f, 0.f, 0.f, 0.f,
			0.f, 1.f, 0.f, 0.f,
			0.f, 0.f, 1.f, 0.f,
			0.f, 0.f, 0.f, 1.f)
		{}

	void updateMatrices();
};

struct Light {
	Vector3f pos;
	Vector3f dir;

	float mtxView[16];
	float mtxProj[16];
	float mtxLight[16];
	float mtxShadow[16];

	float shadowMapBias;
	uint16_t shadowMapSize;

	bool enabled;
	float near;
	float far;
	float area;

	Light() :
		pos (Vector3f(0.f, 10.f, 10.f)),
		dir (Vector3f(-1.f, -1.f, -1.f)),
		mtxView {
			1.f, 0.f, 0.f, 0.f,
			0.f, 1.f, 0.f, 0.f,
			0.f, 0.f, 1.f, 0.f,
			0.f, 0.f, 0.f, 1.f
		},
		mtxProj {
			1.f, 0.f, 0.f, 0.f,
			0.f, 1.f, 0.f, 0.f,
			0.f, 0.f, 1.f, 0.f,
			0.f, 0.f, 0.f, 1.f
		},
		mtxShadow {
			1.f, 0.f, 0.f, 0.f,
			0.f, 1.f, 0.f, 0.f,
			0.f, 0.f, 1.f, 0.f,
			0.f, 0.f, 0.f, 1.f
		},
		shadowMapBias (0.004f),
		shadowMapSize (2048),
		near (0.1f),
		far (100.f),
		area (10.f),
		enabled (false)
	{
	}
};

struct Transform {
	Quaternion rotation = Quaternion (0.0f, 0.0f, 0.0f, 1.0f);
	Vector3f translation = Vector3f (0.0f, 0.0f, 0.0f);
	Vector3f scale = Vector3f (1.0f, 1.0f, 1.0f);

	Transform () {};

	Transform (
			const Vector3f &translation,
			const Quaternion &rotation,
			const Vector3f &scale)
		:
		translation(translation),
		rotation(rotation),
		scale(scale)
	{}

	Transform (const Matrix44f& mat) {
		fromMatrix(mat);
	}
	
	Matrix44f toMatrix() const {
		Matrix44f result;

		Matrix33f scale_mat (
				scale[0], 0.0f, 0.0f,
				0.0f, scale[1], 0.0f,
				0.0f, 0.0f, scale[2]
				);
		result.block<3,3>(0,0) = scale_mat * rotation.toMatrix();
		result.block<1,3>(3,0) = translation.transpose();
		result.block<3,1>(0,3) = Vector3f::Zero();
		result(3,3) = 1.0f;

		return result;
	}

	void fromMatrix(const Matrix44f &matrix) {
		// Extract rotation matrix and the quaternion
		Matrix33f rot_matrix (matrix.block<3,3>(0,0));

		Vector3f row0 = rot_matrix.block<1,3>(0,0).transpose();
		Vector3f row1 = rot_matrix.block<1,3>(1,0).transpose();
		Vector3f row2 = rot_matrix.block<1,3>(2,0).transpose();

		scale.set(
				row0.norm(),
				row1.norm(),
				row2.norm()
				);

		rot_matrix.block<1,3>(0,0) = (row0 / scale[0]).transpose();
		rot_matrix.block<1,3>(1,0) = (row1 / scale[1]).transpose();
		rot_matrix.block<1,3>(2,0) = (row2 / scale[2]).transpose();

		rotation = Quaternion::fromMatrix(rot_matrix).normalize();

		row0 = rot_matrix.block<1,3>(0,0).transpose();
		row1 = rot_matrix.block<1,3>(1,0).transpose();
		row2 = rot_matrix.block<1,3>(2,0).transpose();

		Vector3f trans (
				matrix(3,0), 
				matrix(3,1), 
				matrix(3,2)
				);

		translation = trans;
	}
	Transform operator*(const Transform &other) const {
		Matrix44f this_mat (toMatrix());
		Matrix44f other_mat (other.toMatrix());

		return Transform(this_mat * other_mat);
	}
	Vector3f operator*(const Vector3f &vec) const {
		assert(false);
		return Vector3f::Zero();
	}

	static Transform fromTrans(
			const Vector3f &translation
			) {
		return Transform (
				translation, 
				Quaternion(0.0f, 0.0f, 0.0f, 1.0f), 
				Vector3f(1.0f, 1.0f, 1.0f)
				);
	}

	static Transform fromTransRot(
			const Vector3f &translation,
			const Quaternion &rotation
			) {
		return Transform (
				translation, 
				rotation, 
				Vector3f(1.0f, 1.0f, 1.0f)
				);
	}

	static Transform fromTransRot(
			const Vector3f &translation,
			const Matrix33f &rotation
			) {
		return Transform (
				translation, 
				Quaternion::fromMatrix(rotation), 
				Vector3f(1.0f, 1.0f, 1.0f)
				);
	}
	static Transform fromTransRotScale(
			const Vector3f &translation,
			const Quaternion &rotation,
			const Vector3f &scale
			) {
		return Transform (translation, rotation, scale);
	}
};

struct Renderer {
	bool initialized = false;
	uint32_t view_width = 1;
	uint32_t view_height = 1;

	std::vector<Camera> cameras;

	Renderer() :
		initialized(false),
		view_width (0),
		view_height (0)
	{ }

	void Initialize(int width, int height);
	void Shutdown();
	void RenderGl();
	void RenderGui();
	void Resize (int width, int height);
};