From 0cd0d410a1e72568030f75f721380b1821d02b59 Mon Sep 17 00:00:00 2001
From: Sheldon Lee <sheldon@sheldonlee.com>
Date: Sun, 2 Apr 2023 00:41:32 +0100
Subject: [PATCH] Add camera movement

---
 camera.cpp | 44 ++++++++++++++++++++++++++++++++++++++++----
 camera.h   |  5 ++---
 view.cpp   |  5 ++++-
 3 files changed, 46 insertions(+), 8 deletions(-)

diff --git a/camera.cpp b/camera.cpp
index 14dc741..dd73977 100644
--- a/camera.cpp
+++ b/camera.cpp
@@ -1,24 +1,40 @@
 #include "camera.h"
 #include <cmath>
 
-#include <SFML/Graphics/Color.hpp>
-
 #define PI 3.14159265
+#define DEG_RAD PI/180.f
+#define ROTATION_SPEED 180
+#define TRANSLATIONAL_SPEED 100.f
 
 static void drawLine(sf::RenderWindow* window, sf::Vector2f pos, float angle, float length, sf::Color color);
+static void draw(Camera* camera, sf::RenderWindow* window);
+static void move(Camera* camera, float t);
 
-void camera_update(Camera* camera, sf::RenderWindow* window)
+void camera_update(Camera* camera, sf::RenderWindow* window, float t)
 {
 	if (!camera || !window) return; 
 
+	draw(camera, window);
+	move(camera, t);
+}
+
+static void draw(Camera* camera, sf::RenderWindow* window)
+{
+	const float circleRadius = 5.f;
+	sf::CircleShape circle(circleRadius);
+	circle.setPosition(camera->pos);
+	circle.setOrigin(circleRadius, circleRadius);
+	circle.setFillColor(sf::Color::Green);
+
 	drawLine(window, camera->pos, camera->direction, 100, sf::Color::Red);
+	window->draw(circle);
 }
 
 static void drawLine(sf::RenderWindow* window, sf::Vector2f pos, float angle, float length, sf::Color color)
 {
 	if (!window) return;
 
-	sf::Vector2f endOffset(length * cos(angle * PI/180.f), length * sin(angle * PI/180.3));
+	sf::Vector2f endOffset(length * cos(angle * DEG_RAD), length * sin(angle * DEG_RAD));
 	sf::Vertex start(pos);
 	sf::Vertex end(pos + endOffset);
 
@@ -29,3 +45,23 @@ static void drawLine(sf::RenderWindow* window, sf::Vector2f pos, float angle, fl
 
 	window->draw(line, 2, sf::Lines);
 }
+
+static void move(Camera* camera, float t)
+{
+	int forward = 0;
+	int rotation = 0;
+	if (sf::Keyboard::isKeyPressed(sf::Keyboard::F))
+		forward += 1;
+	if (sf::Keyboard::isKeyPressed(sf::Keyboard::S))
+		forward -= 1;
+	if (sf::Keyboard::isKeyPressed(sf::Keyboard::T))
+		rotation +=1;
+	if (sf::Keyboard::isKeyPressed(sf::Keyboard::R))
+		rotation -=1;
+
+	float magnitude = forward * t * TRANSLATIONAL_SPEED;
+	sf::Vector2f offset(magnitude * cos(camera->direction * DEG_RAD), magnitude *sin(camera->direction * DEG_RAD));
+
+	camera->pos += offset;
+	camera->direction += rotation * t * ROTATION_SPEED;
+}
diff --git a/camera.h b/camera.h
index 0f66971..697f78c 100644
--- a/camera.h
+++ b/camera.h
@@ -1,8 +1,7 @@
 #ifndef CAMERA_H
 #define CAMERA_H
 
-#include <SFML/Graphics/RenderWindow.hpp>
-#include <SFML/System/Vector2.hpp>
+#include <SFML/Graphics.hpp>
 
 typedef struct
 {
@@ -12,6 +11,6 @@ typedef struct
 	float fov;
 } Camera;
 
-void camera_update(Camera* camera, sf::RenderWindow* window);
+void camera_update(Camera* camera, sf::RenderWindow* window, float t);
 
 #endif
diff --git a/view.cpp b/view.cpp
index 3cbf59f..63d4de9 100644
--- a/view.cpp
+++ b/view.cpp
@@ -9,6 +9,7 @@ static int handleKeyCode(sf::Keyboard::Key key);
 
 static sf::Uint32 style = sf::Style::Titlebar;
 static sf::RenderWindow window(sf::VideoMode(500, 500), "Raycasting", style);
+static sf::Clock timer;
 
 static Camera camera = { sf::Vector2f(300.f, 250.f), 0.f, 1.f, 70.f };
 
@@ -37,8 +38,10 @@ int view_update()
 	}
 
 	window.clear();
+	
+	sf::Time t = timer.restart();
 	if (!level_update()) return 0;
-	camera_update(&camera, &window);
+	camera_update(&camera, &window, t.asSeconds());
 	window.display();
 
 	return 1;