From 86f3169e4bc6f5ab2eae7587c377bab1fd237c22 Mon Sep 17 00:00:00 2001
From: Stuart Buchanan <stuart_d_buchanan@yahoo.co.uk>
Date: Sun, 8 Dec 2019 17:36:23 +0000
Subject: [PATCH] Shader Buildings - fix roof orientation

Correct transformation to make roof ridges match orientation
in documentation.
---
 simgear/scene/tgdb/SGBuildingBin.cxx | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/simgear/scene/tgdb/SGBuildingBin.cxx b/simgear/scene/tgdb/SGBuildingBin.cxx
index 2208f1e8..2a56f309 100644
--- a/simgear/scene/tgdb/SGBuildingBin.cxx
+++ b/simgear/scene/tgdb/SGBuildingBin.cxx
@@ -595,16 +595,16 @@ typedef QuadTreeBuilder<LOD*, SGBuildingBin::BuildingInstance, MakeBuildingLeaf,
 
       if ((roof_shape == 2) || (roof_shape == 6) || (roof_shape == 10)  || (roof_shape == 11)) {
         // Gabled, gambrel, round, saltbox
-        if (roof_orientation == 0) rooftop_scale = Vec2f(1.0f, 0.0f);
-        if (roof_orientation == 1) rooftop_scale = Vec2f(0.0f, 1.0f);
+        if (roof_orientation == 0) rooftop_scale = Vec2f(0.0f, 1.0f);
+        if (roof_orientation == 1) rooftop_scale = Vec2f(1.0f, 0.0f);
       }
 
       if ((roof_shape == 3) || (roof_shape == 4) || (roof_shape == 7)) {
         // Hipped, half-hipped, mansard
         // The pitch height expressed as a fraction of the building width/depth such that the hipped
         // roof has a pitch of around 45 degrees.  A minimum of 0.5 so that they have at least some ridge.
-        if (roof_orientation == 0) rooftop_scale = Vec2f(max(0.5f,(width -  2*pitch_height) / width), 0.0f);
-        if (roof_orientation == 1) rooftop_scale = Vec2f(0.0f, max(0.5f,(depth -  2*pitch_height) / width));
+        if (roof_orientation == 0) rooftop_scale = Vec2f(0.0f, max(0.5f,(depth -  2*pitch_height) / width));
+        if (roof_orientation == 1) rooftop_scale = Vec2f(max(0.5f,(width -  2*pitch_height) / width), 0.0f);
       }
 
       // Pyramidal, dome, onion