From b2270b93ef5c2d2127bb2c6a417088d5dce319ad Mon Sep 17 00:00:00 2001
From: codeanticode <andres.colubri@gmail.com>
Date: Sat, 11 Feb 2012 02:18:24 +0000
Subject: [PATCH] Fixed a couple of bugs in the calculation of the normal
 matrix

---
 .../src/processing/core/FillShaderVertFull.glsl     | 12 ++++++++----
 .../core/src/processing/core/FillShaderVertLit.glsl |  4 +++-
 .../src/processing/core/PGraphicsAndroid3D.java     | 13 ++++++++-----
 3 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/android/core/src/processing/core/FillShaderVertFull.glsl b/android/core/src/processing/core/FillShaderVertFull.glsl
index a1cb921b6..3f3be51a7 100644
--- a/android/core/src/processing/core/FillShaderVertFull.glsl
+++ b/android/core/src/processing/core/FillShaderVertFull.glsl
@@ -73,6 +73,7 @@ float blinnPhongFactor(vec3 lightDir, vec3 lightPos, vec3 vecNormal, float shine
 }
 
 void main() {
+  // Vertex in clip coordinates
   gl_Position = projmodelviewMatrix * inVertex;
     
   // Vertex in eye coordinates
@@ -99,8 +100,8 @@ void main() {
       falloff = one_float;
       lightDir = -lightNormal[i];
     } else {
-      falloff = falloffFactor(lightPos, ecVertex, lightFalloffCoefficients[i]);      
-      lightDir = lightPos - ecVertex;
+      falloff = falloffFactor(lightPos, ecVertex, lightFalloffCoefficients[i]);  
+      lightDir = normalize(lightPos - ecVertex);
     }
   
     spotf = spotExp > zero_float ? spotFactor(lightPos, ecVertex, lightNormal[i], 
@@ -110,21 +111,24 @@ void main() {
     if (any(greaterThan(lightAmbient[i], zero_vec3))) {
       totalAmbient  += lightAmbient[i] * falloff;
     }
+    
     if (any(greaterThan(lightDiffuse[i], zero_vec3))) {
       totalDiffuse  += lightDiffuse[i] * falloff * spotf * 
                        lambertFactor(-lightDir, ecNormal);
     }
+    
     if (any(greaterThan(lightSpecular[i], zero_vec3))) {
       totalSpecular += lightSpecular[i] * falloff * spotf * 
                        blinnPhongFactor(-lightDir, lightPos, ecNormal, inShine);
-    }
+    }    
   }    
   
+  // Calculating final color as result of all lights (plus emissive term)
   vertColor = vec4(totalAmbient, 1) * inAmbient + 
               vec4(totalDiffuse, 1) * inColor + 
               vec4(totalSpecular, 1) * inSpecular + 
               inEmissive;
               
   // Passing texture coordinates to the fragment shader
-  vertTexcoord = inTexcoord;              
+  vertTexcoord = inTexcoord;                
 }
diff --git a/android/core/src/processing/core/FillShaderVertLit.glsl b/android/core/src/processing/core/FillShaderVertLit.glsl
index c2dc07dba..08d4b6e01 100644
--- a/android/core/src/processing/core/FillShaderVertLit.glsl
+++ b/android/core/src/processing/core/FillShaderVertLit.glsl
@@ -71,6 +71,7 @@ float blinnPhongFactor(vec3 lightDir, vec3 lightPos, vec3 vecNormal, float shine
 }
 
 void main() {
+  // Vertex in clip coordinates
   gl_Position = projmodelviewMatrix * inVertex;
     
   // Vertex in eye coordinates
@@ -97,7 +98,7 @@ void main() {
       falloff = one_float;
       lightDir = -lightNormal[i];
     } else {
-      falloff = falloffFactor(lightPos, ecVertex, lightFalloffCoefficients[i]);      
+      falloff = falloffFactor(lightPos, ecVertex, lightFalloffCoefficients[i]);  
       lightDir = normalize(lightPos - ecVertex);
     }
   
@@ -120,6 +121,7 @@ void main() {
     }    
   }    
   
+  // Calculating final color as result of all lights (plus emissive term)
   vertColor = vec4(totalAmbient, 1) * inAmbient + 
               vec4(totalDiffuse, 1) * inColor + 
               vec4(totalSpecular, 1) * inSpecular + 
diff --git a/android/core/src/processing/core/PGraphicsAndroid3D.java b/android/core/src/processing/core/PGraphicsAndroid3D.java
index a7e988b16..a9f34372b 100644
--- a/android/core/src/processing/core/PGraphicsAndroid3D.java
+++ b/android/core/src/processing/core/PGraphicsAndroid3D.java
@@ -1437,6 +1437,7 @@ public class PGraphicsAndroid3D extends PGraphics {
       // remove any additional modelview transformation (and less likely, projection
       // transformations) applied by the user after setting the camera and/or projection      
       modelview.set(camera);
+      modelviewInv.set(cameraInv);
       calcProjmodelview();
     }
       
@@ -1672,7 +1673,9 @@ public class PGraphicsAndroid3D extends PGraphics {
     }
     
     // The normal matrix is the transpose of the inverse of the
-    // modelview:
+    // modelview (remember that gl matrices are column-major, 
+    // meaning that elements 0, 1, 2 are the first column,
+    // 3, 4, 5 the second, etc.:
     glNormal[0] = modelviewInv.m00; 
     glNormal[1] = modelviewInv.m01; 
     glNormal[2] = modelviewInv.m02;
@@ -2202,7 +2205,7 @@ public class PGraphicsAndroid3D extends PGraphics {
       }          
       
       if (flushMode == FLUSH_WHEN_FULL && !hints[DISABLE_TRANSFORM_CACHE]) {
-        popMatrix();
+        //popMatrix();
       }
     }
     
@@ -7662,9 +7665,9 @@ public class PGraphicsAndroid3D extends PGraphics {
         fillVertices[index  ] = x * mm.m20 + y * mm.m21 + z * mm.m22 + mm.m23;
         
         index = 3 * fillVertexCount;
-        fillNormals[index++] = nx * nm.m00 + ny * nm.m10 + nz * nm.m02;
-        fillNormals[index++] = nx * nm.m01 + ny * nm.m11 + nz * nm.m12;
-        fillNormals[index  ] = nx * nm.m02 + ny * nm.m21 + nz * nm.m22;
+        fillNormals[index++] = nx * nm.m00 + ny * nm.m10 + nz * nm.m20;
+        fillNormals[index++] = nx * nm.m01 + ny * nm.m11 + nz * nm.m21;
+        fillNormals[index  ] = nx * nm.m02 + ny * nm.m12 + nz * nm.m22;
       } else {
         index = 3 * fillVertexCount;
         fillVertices[index++] = x;