From 4a9d85ba1c84e660d0d8bba33bb0c989b46b337e Mon Sep 17 00:00:00 2001
From: Sheldon Lee <sheldon@sheldonlee.com>
Date: Thu, 20 Apr 2023 02:21:21 +0100
Subject: [PATCH] Implement basic first person view rendering.

---
 firstperson.cpp | 24 ++++++++++++++++++++----
 firstperson.h   |  3 ++-
 view.cpp        |  6 +++---
 3 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/firstperson.cpp b/firstperson.cpp
index 5af43a0..9373aeb 100644
--- a/firstperson.cpp
+++ b/firstperson.cpp
@@ -20,16 +20,32 @@ int firstperson_init(unsigned int _width, unsigned int _height)
 	return 1;
 }
 
-void firstperson_update(sf::RenderTarget* renderTarget)
+void firstperson_update(sf::RenderTarget* renderTarget, Camera* camera)
 {
+	const float columnWidth = (float)width/(float)camera->resolution;
+	float columnHeight = 0;
 	renderTexture.clear();
-	sf::CircleShape shape(50);
-	renderTexture.draw(shape);
-	renderTexture.display();
 
+	for (unsigned int i = 0; i < camera->resolution; i++) {
+		float distance = camera->rays[i].distance;
+		if (distance > 0.f) columnHeight = 0.5f * (float)height/camera->rays[i].distance;
+
+		float centeredHeight = (float)height/2.f - columnHeight/2.f;
+		float distanceScale = distance/10.f;
+		distanceScale = (distanceScale > 1.f)? 1.f : distanceScale;
+		float brightness = 255.f*(1.f-distanceScale);
+
+		sf::RectangleShape rectangle(sf::Vector2f(columnWidth, columnHeight));
+		rectangle.setPosition(sf::Vector2f(i*columnWidth, centeredHeight));
+		rectangle.setFillColor(sf::Color(brightness, brightness, brightness));
+		renderTexture.draw(rectangle);
+	}
+
+	renderTexture.display();
 	sf::Sprite sprite(renderTexture.getTexture());
 	sprite.setPosition(renderTexturePosition);
 	renderTarget->draw(sprite);
+
 }
 
 void firstperson_setTexturePosition(float x, float y)
diff --git a/firstperson.h b/firstperson.h
index 11434ab..1e4e3ae 100644
--- a/firstperson.h
+++ b/firstperson.h
@@ -2,9 +2,10 @@
 #define FIRSTPERSON_H
 
 #include <SFML/Graphics.hpp>
+#include "camera.h"
 
 int firstperson_init(unsigned int width, unsigned int height);
-void firstperson_update(sf::RenderTarget* renderTarget);
+void firstperson_update(sf::RenderTarget* renderTarget, Camera* camera);
 void firstperson_setTexturePosition(float x, float y);
 
 #endif
diff --git a/view.cpp b/view.cpp
index a4a7fcf..7cae58e 100644
--- a/view.cpp
+++ b/view.cpp
@@ -7,7 +7,7 @@
 #include "minimap.h"
 #include "firstperson.h"
 
-#define MINIMAP_SIZE 460
+#define MINIMAP_SIZE 720
 #define VIEW_SIZE MINIMAP_SIZE*2
 
 static int handleKeyCode(sf::Keyboard::Key key);
@@ -21,7 +21,7 @@ static sf::Clock timer;
 int view_init()
 {
 	printf("view_init()\n");
-	if (!camera_init(&camera, sf::Vector2f(5.f/2.f, 5.f/2.f), 0.f, 100, 0.5f*PI)) return 0;
+	if (!camera_init(&camera, sf::Vector2f(10.f/2.f, 10.f/2.f), 0.f, 128, 0.5f*PI)) return 0;
 	if (!minimap_init(MINIMAP_SIZE)) return 0;
 	if (!firstperson_init(VIEW_SIZE, MINIMAP_SIZE)) return 0;
 
@@ -53,7 +53,7 @@ int view_update()
 
 	window.clear();
 	minimap_update(&window, &camera);
-	firstperson_update(&window);
+	firstperson_update(&window, &camera);
 	window.display();
 
 	return 1;