diff --git a/shaders/shader.frag b/shaders/shader.frag
index 1ce7c9f..965830b 100644
--- a/shaders/shader.frag
+++ b/shaders/shader.frag
@@ -1,6 +1,9 @@
 #version 330 core
+in vec3 frag_col;
 out vec4 FragColor;
+
+uniform vec4 MyColor;
 void main()
 {
-    FragColor = vec4(1.0f, 0.5f, 0.2f, 1.0f);
+    FragColor = vec4(frag_col, 1.0f);//vec4(posInWorld.x, posInWorld.y, posInWorld.z, 1.0f);
 } 
\ No newline at end of file
diff --git a/shaders/shader.vert b/shaders/shader.vert
index 5d16282..a287f1b 100644
--- a/shaders/shader.vert
+++ b/shaders/shader.vert
@@ -1,6 +1,10 @@
 #version 330 core
 layout (location = 0) in vec3 aPos;
+layout (location = 1) in vec3 col;
+out vec3 frag_col;
+
 void main()
 {
+    frag_col = col;
     gl_Position = vec4(aPos.x, aPos.y, aPos.z, 1.0);
 }
\ No newline at end of file
diff --git a/src/main.cpp b/src/main.cpp
index 02fbf2f..6745967 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -3,6 +3,10 @@
 #include <iostream>
 #include <fstream>
 #include <cstring>
+#include <cmath>
+#include <cstdlib>
+
+#define RAND_0_1 ((float)rand()) / RAND_MAX
 
 void framebufferSizeCallback(GLFWwindow *window, int width, int height) {
     glViewport(10, 10, width-10, height-10);
@@ -36,11 +40,23 @@ std::string readFile(std::string path) {
 	}
 
 	content += '\0';
-	std::cout << content << std::endl;
 	file.close();
 	return content;
 }
 
+void updateVertices(float (&vertices)[24]) {
+	// if (RAND_0_1 < 0.99f) return; 
+	float a[] = {
+		-1.0f, 1.0f, 0.0f,  RAND_0_1, RAND_0_1, RAND_0_1,    // upper left
+    	-1.0f, -1.0f, 0.0f,  RAND_0_1, RAND_0_1, RAND_0_1,   // bottom left
+     	1.0f,  1.0f, 0.0f,  RAND_0_1, RAND_0_1, RAND_0_1,    // upper right
+		1.0f, -1.0f, 0.0f,  RAND_0_1, RAND_0_1, RAND_0_1     // bottom right
+	};
+
+	// vertices = a;
+	memcpy(vertices, a, sizeof(a));
+}
+
 unsigned int prepareShaders() {
 	unsigned int vertexShader = glCreateShader(GL_VERTEX_SHADER);
 	unsigned int fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
@@ -91,6 +107,7 @@ unsigned int prepareShaders() {
 }
 
 int main () {
+	srand(time(0));
 	glfwInit();
 	glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
 	glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
@@ -116,22 +133,34 @@ int main () {
 	unsigned int shaderProgram = prepareShaders();
 
 	float vertices[] = {
-		-0.5, 0.0, 0.0,
-		0.5, 0.5, 0.0,
-		0.5, -0.5, 0.0
+		-1.0f, 1.0f, 0.0f,  1.0f, 0.0f, 0.0f,    // upper left
+    	-1.0f, -1.0f, 0.0f,  0.0f, 1.0f, 0.0f,   // bottom left
+     	1.0f,  1.0f, 0.0f,  1.0f, 0.0f, 0.0f,    // upper right
+		1.0f, -1.0f, 0.0f,  0.0f, 1.0f, 0.0f     // bottom right
 	};
-
-	unsigned int VBO, VAO;
+	unsigned int indices[] = {
+		1, 2, 3,
+		1, 2, 0
+	};
+	unsigned int VBO, VAO, EBO;
 	glGenVertexArrays(1, &VAO);
 	glGenBuffers(1, &VBO);
+	glGenBuffers(1, &EBO);
+
 	glBindVertexArray(VAO);
 
 	glBindBuffer(GL_ARRAY_BUFFER, VBO);
-	glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
+	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, EBO);
 
-	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 3 * sizeof(float), (void*)0);
+	glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
+	glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), indices, GL_STATIC_DRAW);
+
+	glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void*)0);
 	glEnableVertexAttribArray(0);
-	glBindBuffer(GL_ARRAY_BUFFER, 0);
+
+	glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 6 * sizeof(float), (void*) (3 * sizeof(float)));
+	glEnableVertexAttribArray(1);
+
 	glBindVertexArray(0);
 	
 	while(!glfwWindowShouldClose(window)) {
@@ -141,9 +170,20 @@ int main () {
 		glClear(GL_COLOR_BUFFER_BIT);
 	
 		glUseProgram(shaderProgram);
-		glBindVertexArray(VAO);
-		glDrawArrays(GL_TRIANGLES, 0, 3);
 
+		// float time = glfwGetTime();
+		// float greenValue = sin(time);
+		
+
+		// int vertexColorLocation = glGetUniformLocation(shaderProgram, "MyColor");
+		// glUniform4f(vertexColorLocation, 0, greenValue, 0, 1);
+		glBindVertexArray(VAO);
+
+		updateVertices(vertices);
+		glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_DYNAMIC_DRAW);
+		glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
+
+		glBindVertexArray(0);
 	    glfwSwapBuffers(window);
 	    glfwPollEvents();
 	}
diff --git a/src/ui/ui.cpp b/src/ui/ui.cpp
new file mode 100644
index 0000000..45e46a5
--- /dev/null
+++ b/src/ui/ui.cpp
@@ -0,0 +1,5 @@
+#include "ui.hpp"
+
+void UI::draw() {
+
+};
\ No newline at end of file
diff --git a/src/ui/ui.hpp b/src/ui/ui.hpp
new file mode 100644
index 0000000..23302f0
--- /dev/null
+++ b/src/ui/ui.hpp
@@ -0,0 +1,4 @@
+class UI {
+    void draw();
+    
+};
\ No newline at end of file