From ce1da5f7a876e12632ad326fa31bdf424bebcbc5 Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop+git@gmail.com>
Date: Tue, 27 Oct 2009 21:31:21 +0000
Subject: [PATCH] working on drawing planes

git-svn-id: svn://anubis/anaglym/trunk@127 99a6e188-d820-4881-8870-2d33a10e2619
---
 Engine.cc | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/Engine.cc b/Engine.cc
index a48b913..fa97ba0 100644
--- a/Engine.cc
+++ b/Engine.cc
@@ -759,7 +759,28 @@ void Engine::Object::render()
         case OdeWorld::SPHERE:
             gluSphere(quad, (*m_args)[0], 16, 8);
             break;
-        case OdeWorld::PLANE:
+        case OdeWorld::PLANE: {
+            dMatrix3 r;
+            dRFromEulerAngles(r, (*m_args)[3], (*m_args)[4], (*m_args)[5]);
+            dVector3 default_plane_direction = {0, 0, 1, 0};
+            dVector3 default_x = {1, 0, 0, 0};
+            dVector3 default_y = {0, 1, 0, 0};
+            dVector3 rotated_plane_direction;
+            dVector3 rotated_x;
+            dVector3 rotated_y;
+            dMultiply0(rotated_plane_direction, default_plane_direction, r, 1, 3, 3);
+            dMultiply0(rotated_x, default_x, r, 1, 3, 3);
+            dMultiply0(rotated_y, default_y, r, 1, 3, 3);
+
+            float a = rotated_plane_direction[0];
+            float b = rotated_plane_direction[1];
+            float c = rotated_plane_direction[2];
+            float d = (a * (*m_args)[0] + b * (*m_args)[1] + c * (*m_args)[2]);
+            /* plane equation: ax + by + cz = d, plane normal: (a, b, c) */
+            glBegin(GL_QUAD_STRIP);
+            glNormal3f(a, b, c);
+            glEnd();
+            }
             break;
         case OdeWorld::CYLINDER:
             glPushMatrix();