#include "Camera2D.h"

#include "Exception.h"

Camera2D::Camera2D(const vec2& size, const vec2& position)
	: Camera2D(vec3(size.x, size.y, 2.0f), vec3(position.x, position.y, 0.0f)) {}

Camera2D::Camera2D(const vec3& size, const vec3& position)
{
	update_size(size);
	update_position(position);
}

void Camera2D::update_size(const vec3& size)
{
	m_size = size;
	update_scale();
}

void Camera2D::update_position(const vec3& position)
{
	m_position = position;
}

void Camera2D::translate(const vec2& translation)
{
	translate(vec3(translation.x, translation.y, 0.0f));
}

void Camera2D::translate(const vec3& translation)
{
	m_position += translation;
}

void Camera2D::prerender()
{
	m_view_matrix[3][0] = -m_position.x;
	m_view_matrix[3][1] = -m_position.y;
	m_view_matrix[3][2] = -m_position.z;
}

void Camera2D::update_scale()
{
	m_projection_matrix[0][0] = 2.0f / m_size.x;
	m_projection_matrix[1][1] = 2.0f / m_size.y;
	m_projection_matrix[2][2] = -2.0f / m_size.z;
}