From a278d1843fe808f41423ada3d0a40b925efbf82e Mon Sep 17 00:00:00 2001
From: Josh Holtrop <jholtrop+git@gmail.com>
Date: Tue, 10 May 2011 23:38:26 -0400
Subject: [PATCH] store matrices in column-major mode

---
 glslUtil/glslUtil.c | 54 ++++++++++++++++++++++-----------------------
 lighting/test.cc    |  4 ++--
 2 files changed, 29 insertions(+), 29 deletions(-)

diff --git a/glslUtil/glslUtil.c b/glslUtil/glslUtil.c
index af316f8..b29133c 100644
--- a/glslUtil/glslUtil.c
+++ b/glslUtil/glslUtil.c
@@ -52,9 +52,9 @@ void guMatrixMult(guMatrix4x4 *m, guMatrix4x4 *a, guMatrix4x4 *b)
             GLfloat v = 0.0;
             for (p = 0; p < 4; p++)
             {
-                v += (*a)[i][p] * (*b)[p][j];
+                v += (*a)[p][i] * (*b)[j][p];
             }
-            (*m)[i][j] = v;
+            (*m)[j][i] = v;
         }
     }
 }
@@ -64,7 +64,7 @@ void guMatrixTranslate(guMatrix4x4 *m, GLfloat x, GLfloat y, GLfloat z)
     int i;
     for (i = 0; i < 4; i++)
     {
-        (*m)[i][3] += (*m)[i][0] * x + (*m)[i][1] * y + (*m)[i][2] * z;
+        (*m)[3][i] += (*m)[0][i] * x + (*m)[1][i] * y + (*m)[2][i] * z;
     }
 }
 
@@ -73,10 +73,9 @@ void guMatrixScale(guMatrix4x4 *m, GLfloat x, GLfloat y, GLfloat z)
     int i;
     for (i = 0; i < 4; i++)
     {
-        GLfloat *base = &(*m)[i][0];
-        base[0] *= x;
-        base[1] *= y;
-        base[2] *= z;
+        (*m)[0][i] *= x;
+        (*m)[1][i] *= y;
+        (*m)[2][i] *= z;
     }
 }
 
@@ -97,20 +96,20 @@ void guMatrixRotate(guMatrix4x4 *m, GLfloat angle,
     guMatrix4x4 mult;
     GLfloat oc = 1 - c;
     mult[0][0] = lx * lx * oc + c;
-    mult[0][1] = lx * ly * oc - lz * s;
-    mult[0][2] = lx * lz * oc + ly * s;
-    mult[0][3] = 0.0;
-    mult[1][0] = ly * lx * oc + lz * s;
-    mult[1][1] = ly * ly * oc + c;
-    mult[1][2] = ly * lz * oc - lx * s;
-    mult[1][3] = 0.0;
-    mult[2][0] = lx * lz * oc - ly * s;
-    mult[2][1] = ly * lz * oc + lx * s;
-    mult[2][2] = lz * lz * oc + c;
-    mult[2][3] = 0.0;
+    mult[1][0] = lx * ly * oc - lz * s;
+    mult[2][0] = lx * lz * oc + ly * s;
     mult[3][0] = 0.0;
+    mult[0][1] = ly * lx * oc + lz * s;
+    mult[1][1] = ly * ly * oc + c;
+    mult[2][1] = ly * lz * oc - lx * s;
     mult[3][1] = 0.0;
+    mult[0][2] = lx * lz * oc - ly * s;
+    mult[1][2] = ly * lz * oc + lx * s;
+    mult[2][2] = lz * lz * oc + c;
     mult[3][2] = 0.0;
+    mult[0][3] = 0.0;
+    mult[1][3] = 0.0;
+    mult[2][3] = 0.0;
     mult[3][3] = 1.0;
     guMatrixMult(m, m, &mult);
 }
@@ -133,12 +132,12 @@ void guMatrixFrustum(guMatrix4x4 *m,
     GLfloat tb = top - bottom;
     GLfloat fn = far - near;
     mult[0][0] = 2 * near / rl;
-    mult[0][2] = (right + left) / rl;
+    mult[2][0] = (right + left) / rl;
     mult[1][1] = 2 * near / tb;
-    mult[1][2] = (top + bottom) / tb;
+    mult[2][1] = (top + bottom) / tb;
     mult[2][2] = - (far + near) / fn;
-    mult[2][3] = - 2 * far * near / fn;
-    mult[3][2] = -1.0;
+    mult[3][2] = - 2 * far * near / fn;
+    mult[2][3] = -1.0;
     guMatrixMult(m, m, &mult);
 }
 
@@ -159,8 +158,8 @@ void guPerspective(guMatrix4x4 *m, GLfloat fovy, GLfloat aspect,
     mult[0][0] = f / aspect;
     mult[1][1] = f;
     mult[2][2] = (far + near) / nf;
-    mult[2][3] = (2 * far * near) / nf;
-    mult[3][2] = -1.0;
+    mult[3][2] = (2 * far * near) / nf;
+    mult[2][3] = -1.0;
     guMatrixMult(m, m, &mult);
 }
 
@@ -182,12 +181,13 @@ void guOrtho(guMatrix4x4 *m,
     GLfloat tb = top - bottom;
     GLfloat fn = far - near;
     mult[0][0] = 2 / rl;
-    mult[0][3] = - (right + left) / rl;
+    mult[3][0] = - (right + left) / rl;
     mult[1][1] = 2 / tb;
-    mult[1][3] = - (top + bottom) / tb;
+    mult[3][1] = - (top + bottom) / tb;
     mult[2][2] = -2 / fn;
-    mult[2][3] = - (far + near) / fn;
+    mult[3][2] = - (far + near) / fn;
     mult[3][3] = 1.0;
+    guMatrixMult(m, m, &mult);
 }
 
 char *guGetShaderLog(GLuint id)
diff --git a/lighting/test.cc b/lighting/test.cc
index b4c7519..5a993fd 100644
--- a/lighting/test.cc
+++ b/lighting/test.cc
@@ -188,8 +188,8 @@ bool init(int width, int height)
     glUniform4f(diffuse_loc, 1.0, 0.6, 0.0, 1.0);
     glUniform4f(specular_loc, 1.0, 1.0, 1.0, 1.0);
     glUniform1f(shininess_loc, 85.0);
-    glUniformMatrix4fv(projection_loc, 1, GL_TRUE, &projection[0][0]);
-    glUniformMatrix4fv(modelview_loc, 1, GL_TRUE, &modelview[0][0]);
+    glUniformMatrix4fv(projection_loc, 1, GL_FALSE, &projection[0][0]);
+    glUniformMatrix4fv(modelview_loc, 1, GL_FALSE, &modelview[0][0]);
 
     data_vbo = makeBuffer(GL_ARRAY_BUFFER, data, sizeof(data));
     index_vbo = makeBuffer(GL_ELEMENT_ARRAY_BUFFER, indices, sizeof(indices));