From 8841927f6435c260bccba0e538858280c1baf622 Mon Sep 17 00:00:00 2001
From: Mathieu Virbel <mat@kivy.org>
Date: Fri, 5 Oct 2018 10:25:37 +0200
Subject: [PATCH] fix matrix transformation for orthographic projection

---
 kivy/graphics/transformation.pyx | 20 ++++++++------------
 1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/kivy/graphics/transformation.pyx b/kivy/graphics/transformation.pyx
index cd23a1303..e1f5b023a 100644
--- a/kivy/graphics/transformation.pyx
+++ b/kivy/graphics/transformation.pyx
@@ -80,8 +80,8 @@ cdef class Matrix:
             [0.000000, 0.000000, 1.000000, 0.000000],
             [0.000000, 0.000000, 0.000000, 1.000000]]
 
-        you can use this format to plug the result straight into numpy 
-        in this way numpy.array(m.tolist()) 
+        you can use this format to plug the result straight into numpy
+        in this way numpy.array(m.tolist())
 
         .. versionadded:: 1.9.0
         '''
@@ -209,11 +209,11 @@ cdef class Matrix:
 
         :Parameters:
             `x`: float
-                The scale factor along the X axis         
+                The scale factor along the X axis
             `y`: float
                 The scale factor along the Y axis
             `z`: float
-                The scale factor along the Z axis        
+                The scale factor along the Z axis
         '''
         with nogil:
             self.mat[ 0] *= x;
@@ -226,7 +226,7 @@ cdef class Matrix:
 
         :Parameters:
             `x`: float
-                The translation factor along the X axis         
+                The translation factor along the X axis
             `y`: float
                 The translation factor along the Y axis
             `z`: float
@@ -333,7 +333,7 @@ cdef class Matrix:
                 self.mat[13] = (top+bottom)/(bottom-top)
                 self.mat[2]  = 0.0
                 self.mat[6]  = 0.0
-                self.mat[10] = 2.0/(far-near)
+                self.mat[10] = -2.0/(far-near)
                 self.mat[14] = (far+near)/(near-far)
                 self.mat[3]  = 0.0
                 self.mat[7]  = 0.0
@@ -541,7 +541,7 @@ cdef class Matrix:
         the result (not inplace)::
 
             m.multiply(n) -> n * m
-            
+
         :Parameters:
             `ma`: Matrix
                 The matrix to multiply by
@@ -572,7 +572,7 @@ cdef class Matrix:
     cpdef project(Matrix self, double objx, double objy, double objz, Matrix model, Matrix proj,
             double vx, double vy, double vw, double vh):
         '''Project a point from 3d space into a 2d viewport.
-        
+
         :Parameters:
             `objx`: float
                 Points X co-ordinate
@@ -620,7 +620,3 @@ cdef class Matrix:
                    m[4], m[5], m[6], m[7],
                    m[8], m[9], m[10], m[11],
                    m[12], m[13], m[14], m[15])
-
-
-
-