From 3140e190edbf5f9f8c3358661eda5fbde574ee85 Mon Sep 17 00:00:00 2001
From: devZoGok <nenkokeko@yandex.com>
Date: Sat, 18 Dec 2021 19:11:19 +0200
Subject: [PATCH] implemented line rendering

---
 line3D.frag      |  9 +++++
 line3D.vert      |  9 +++++
 lineRenderer.cpp | 90 ++++++++++++++++++++++++++++++++++++++++++++++++
 lineRenderer.h   | 32 +++++++++++++++++
 root.cpp         |  6 ++++
 5 files changed, 146 insertions(+)
 create mode 100644 line3D.frag
 create mode 100644 line3D.vert
 create mode 100644 lineRenderer.cpp
 create mode 100644 lineRenderer.h

diff --git a/line3D.frag b/line3D.frag
new file mode 100644
index 0000000..e43947d
--- /dev/null
+++ b/line3D.frag
@@ -0,0 +1,9 @@
+#version 330 core
+
+out vec4 FragColor;
+
+uniform vec3 color;
+
+void main(){
+	FragColor = vec4(color, 1);
+}
diff --git a/line3D.vert b/line3D.vert
new file mode 100644
index 0000000..956fb2f
--- /dev/null
+++ b/line3D.vert
@@ -0,0 +1,9 @@
+#version 330 core
+
+layout (location = 0) in vec3 aPos;
+
+uniform mat4 proj, view;
+
+void main(){
+	gl_Position = proj * view * vec4(aPos, 1);
+}
diff --git a/lineRenderer.cpp b/lineRenderer.cpp
new file mode 100644
index 0000000..6b1acbb
--- /dev/null
+++ b/lineRenderer.cpp
@@ -0,0 +1,90 @@
+#include "lineRenderer.h"
+#include "root.h"
+
+#include "glad.h"
+
+#include <glm.hpp>
+#include <ext.hpp>
+
+using namespace std;
+using namespace glm;
+
+namespace vb01{
+		LineRenderer *lineRenderer = nullptr;
+
+		LineRenderer* LineRenderer::getSingleton(){
+				if(!lineRenderer)
+						lineRenderer = new LineRenderer();
+
+				return lineRenderer;
+		}
+
+		LineRenderer::LineRenderer(){
+				shader = new Shader(Root::getSingleton()->getLibPath() + "line3D");
+		}
+
+		void LineRenderer::drawLines(){
+			Root *root = Root::getSingleton();
+			Camera *cam = root->getCamera();
+
+			Vector3 dir = cam->getDirection(), up = cam->getUp();
+			Vector3 camPos = cam->getPosition();
+			mat4 view = lookAt(vec3(camPos.x, camPos.y, camPos.z), vec3(camPos.x + dir.x, camPos.y + dir.y, camPos.z + dir.z), vec3(up.x, up.y, up.z));
+
+			float fov = cam->getFov(), width = root->getWidth(), height = root->getHeight(), nearPlane = cam->getNearPlane(), farPlane = cam->getFarPlane();
+			mat4 proj = perspective(radians(fov), width / height, nearPlane, farPlane);
+
+			for(Line &l : lines){
+				shader->use();
+				shader->setVec3(l.color, "color");
+				shader->setMat4(proj, "proj");
+				shader->setMat4(view, "view");
+
+				glBegin(GL_LINES);
+				glVertex3f(l.start.x, l.start.y, l.start.z);
+				glVertex3f(l.end.x, l.end.y, l.end.z);
+				glEnd();
+			}
+		}
+
+		void LineRenderer::addLine(Vector3 start, Vector3 end, Vector3 color){
+				Line line;
+				line.id = nextId;
+				line.start = start;
+				line.end = end;
+				line.color = color;
+				lines.push_back(line);
+
+				nextId++;
+		}
+
+		LineRenderer::Line& LineRenderer::getLine(int i){
+				for(Line &l : lines)
+						if(l.id == i)
+								return l;
+		}
+
+		void LineRenderer::changeLineField(int id, Vector3 vec, VectorFieldType field){
+				Line &line = LineRenderer::getLine(id);
+
+				switch(field){
+						case VectorFieldType::START:
+								line.start = vec;
+								break;
+						case VectorFieldType::END:
+								line.end = vec;
+								break;
+						case VectorFieldType::COLOR:
+								line.color= vec;
+								break;
+				}
+		}
+
+		void LineRenderer::removeLine(int id){
+				for(Line &l : lines)
+						if(l.id == id){
+								lines.erase(lines.begin() + id);
+								break;
+						}
+		}
+}
diff --git a/lineRenderer.h b/lineRenderer.h
new file mode 100644
index 0000000..1f42aca
--- /dev/null
+++ b/lineRenderer.h
@@ -0,0 +1,32 @@
+#ifndef LINE_H
+#define LINE_H
+
+#include "vector.h"
+#include "mesh.h"
+
+#include <vector>
+
+namespace vb01{
+		class Shader;
+
+		class LineRenderer{
+				public:
+						struct Line{int id; Vector3 start; Vector3 end; Vector3 color;};
+						enum VectorFieldType{START, END, COLOR};
+
+						static LineRenderer* getSingleton();
+						void drawLines();
+						void addLine(Vector3 start, Vector3 end, Vector3 color);
+						void changeLineField(int, Vector3, VectorFieldType);
+						void removeLine(int);
+						Line& getLine(int);
+				private:
+						LineRenderer();
+
+						int nextId = 0;
+						Shader *shader = nullptr;
+						std::vector<LineRenderer::Line> lines;
+		};
+}
+
+#endif
diff --git a/root.cpp b/root.cpp
index 81cf6f0..bc04e57 100755
--- a/root.cpp
+++ b/root.cpp
@@ -4,6 +4,7 @@
 #include "shader.h"
 #include "box.h"
 #include "quad.h"
+#include "lineRenderer.h"
 
 #include "glad.h"
 #include <glfw3.h>
@@ -15,6 +16,7 @@ using namespace std;
 
 namespace vb01{
 	static Root *root = nullptr;
+	Shader *shader = nullptr;
 
 	Root* Root::getSingleton(){
 		if(!root)
@@ -55,6 +57,8 @@ namespace vb01{
 		initMainFramebuffer(fragTexture, brightTexture);
 		initBloomFramebuffer();
 		initGuiPlane(fragTexture, brightTexture);
+
+			shader = new Shader(Root::getSingleton()->getLibPath() + "line3D");
 	}
 
 	void Root::initWindow(string name){
@@ -148,6 +152,8 @@ namespace vb01{
 
 		rootNode->update();
 
+		LineRenderer::getSingleton()->drawLines();
+
 		glBindFramebuffer(GL_FRAMEBUFFER, 0);
 		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);