From 1dca5470f6b163db11f6f71e1916e592ac3239aa Mon Sep 17 00:00:00 2001
From: hodasemi <superschneider@t-online.de>
Date: Fri, 31 May 2019 14:31:02 +0200
Subject: [PATCH] Render cube

---
 exercise3/src/cube_system.cpp | 86 ++++++++++++++++++++++++++++++-----
 1 file changed, 74 insertions(+), 12 deletions(-)

diff --git a/exercise3/src/cube_system.cpp b/exercise3/src/cube_system.cpp
index 861cd7d..280bd65 100644
--- a/exercise3/src/cube_system.cpp
+++ b/exercise3/src/cube_system.cpp
@@ -1,6 +1,6 @@
 //
-// This source code is property of the Computer Graphics and Visualization 
-// chair of the TU Dresden. Do not distribute in modified or unmodified form! 
+// This source code is property of the Computer Graphics and Visualization
+// chair of the TU Dresden. Do not distribute in modified or unmodified form!
 // Copyright (C) 2016 CGV TU Dresden - All Rights Reserved
 //
 #include "cube_system.h"
@@ -51,17 +51,17 @@ void cube_system::render_system()
 {
 	/********
 	Task 2.1.2.    Program the transformation tree from the exercise sheet. To store the
-	               active aggregated transformation matrix on top of a stack use glPushMatrix 
+	               active aggregated transformation matrix on top of a stack use glPushMatrix
 				   and to reactivate and remove the top element of the transformation stack
 				   use glPopMatrix. For animation a variable "angle" (which has values
 				   between 0 and 359) is defined. Use it for rotations as defined in
 				   the transformation tree.
 	Aufgabe 2.1.2. Programmieren Sie den Transformationsbaum aus dem Uebungsblatt.
-	               Nutzen Sie glPushMatrix um die aktuelle Gesamttransformations-Matrix an die 
+	               Nutzen Sie glPushMatrix um die aktuelle Gesamttransformations-Matrix an die
 				   Spitze eines Stacks zu speichern und glPopMatrix um die vorderste Matrix
 				   im Stack zu entfernen und zu reaktivieren. Fuer Animationen steht eine Variable
-				   "angle" zur Verfuegung (die Werte zwischen 0 und 359 enthält). Nutzen Sie diese
-				   Variable für Rotationen analog zu den Angaben im gegebenen Transformationsbaum.
+				   "angle" zur Verfuegung (die Werte zwischen 0 und 359 enth�lt). Nutzen Sie diese
+				   Variable f�r Rotationen analog zu den Angaben im gegebenen Transformationsbaum.
 	*********/
 
 
@@ -73,22 +73,84 @@ void cube_system::render_system()
 
 
 
-
+void render_cube_face(
+	const double color[3],
+	const double p0[3],
+	const double p1[3],
+	const double p2[3],
+	const double p3[3])
+{
+	glVertex3dv(p0);
+	glColor3dv(color);
+	glVertex3dv(p1);
+	glColor3dv(color);
+	glVertex3dv(p2);
+	glColor3dv(color);
+	glVertex3dv(p2);
+	glColor3dv(color);
+	glVertex3dv(p3);
+	glColor3dv(color);
+	glVertex3dv(p0);
+	glColor3dv(color);
+}
 
 // Render one single cube
 void cube_system::render_cube()
 {
 	/********
-	Task 2.1.1.    Tesellate a cube by specifying vertices and colors via the commands 
-	               glVertex3d and glColor3d. Choose appropriate primitives (parameter to 
-				   glBegin) and provide vertices and colors for all 6 sides. The cube shall 
+	Task 2.1.1.    Tesellate a cube by specifying vertices and colors via the commands
+	               glVertex3d and glColor3d. Choose appropriate primitives (parameter to
+				   glBegin) and provide vertices and colors for all 6 sides. The cube shall
 				   range from (-1, -1, -1) to (1, 1, 1).
 	Aufgabe 2.1.1. Tesellieren Sie einen Wuerfel, indem Sie Vertices und Farben mittels
 	               der Kommandos glVertex3d und glColor3d spezifizieren. Waehlen Sie
 				   zunaechst das passende Zeichenprimitiv (Parameter von glBegin) und
-                   erstellen Sie Vertices und Farben für alle 6 Seiten. Der Wuerfel soll
+                   erstellen Sie Vertices und Farben f�r alle 6 Seiten. Der Wuerfel soll
 				   von (-1, -1, -1) bis (1, 1, 1) reichen.
 	*********/
+
+	/*
+
+		4 ----------- 3
+	   /.			 /|
+	  /	.			/ |
+	 /	.		   /  |
+	1 ----------- 2   |
+	|	8 . . . . | . 7
+	|  .		  |	 /
+	| .	          | /
+	|.			  |/
+	5 ----------- 6
+
+	*/
+
+	const double vertices[8][3] = {
+		{-1.0, -1.0,  1.0},
+		{ 1.0, -1.0,  1.0},
+		{ 1.0,  1.0,  1.0},
+		{-1.0,  1.0,  1.0},
+		{-1.0, -1.0, -1.0},
+		{ 1.0, -1.0, -1.0},
+		{ 1.0,  1.0, -1.0},
+		{-1.0,  1.0, -1.0}
+	};
+
+	const double colors[6][3] = {
+		{1.0, 0.0, 0.0},
+		{0.0, 1.0, 0.0},
+		{0.0, 0.0, 1.0},
+		{1.0, 1.0, 0.0},
+		{1.0, 0.0, 1.0},
+		{0.0, 1.0, 1.0},
+	};
+
+	render_cube_face(colors[0], vertices[0], vertices[1], vertices[2], vertices[3]);
+	render_cube_face(colors[1], vertices[1], vertices[5], vertices[6], vertices[2]);
+	render_cube_face(colors[2], vertices[5], vertices[4], vertices[7], vertices[6]);
+	render_cube_face(colors[3], vertices[4], vertices[0], vertices[3], vertices[7]);
+	render_cube_face(colors[4], vertices[4], vertices[5], vertices[1], vertices[0]);
+	render_cube_face(colors[5], vertices[6], vertices[7], vertices[3], vertices[2]);
+
 }
 
 
@@ -116,5 +178,5 @@ void cube_system::setup_projection()
 // Set debug text
 void cube_system::set_text(std::stringstream &stream)
 {
-	stream<<"Showing cube system (with rotation parameter at "<<angle<<"°)";
+	stream<<"Showing cube system (with rotation parameter at "<<angle<<"�)";
 }
\ No newline at end of file