changed to a triangle

src/main.cpp

@@ -34,16 +34,14 @@ int main()
 	glfwSetFramebufferSizeCallback(window, framebuffer_size_callback);
 
 	float vertices[] = {
-	     0.5f,  0.5f, 0.0f,  // top right
-	     0.5f, -0.5f, 0.0f,  // bottom right
-	    -0.5f, -0.5f, 0.0f,  // bottom left
-	    -0.5f,  0.5f, 0.0f   // top left 
+	     0.0f,  0.5f, 0.0f,
+	    -0.5f, -0.5f, 0.0f,
+	     0.5f, -0.5f, 0.0f
 	};
 
 	unsigned int indices[] = {  // note that we start from 0!
-	    0, 1, 3,   // first triangle
-	    1, 2, 3    // second triangle
-	};  
+	    0, 1, 2
+	};
 
 	unsigned int VBO;
 	glGenBuffers(1, &VBO);