hi there,i dont want to use glm lib，so i change code like below

glm code

```
glm::mat4 lightProjection, lightView;
glm::mat4 lightSpaceMatrix;
GLfloat near_plane = 1.0f, far_plane = 7.5f;
lightProjection = glm::ortho(-10.0f, 10.0f, -10.0f, 10.0f, near_plane, far_plane);
lightView = glm::lookAt(lightPos, glm::vec3(0.0f), glm::vec3(0.0, 1.0, 0.0));
lightSpaceMatrix = lightProjection * lightView;
```

i change it like this:

```
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
GLfloat near_plane = 1.0f, far_plane = 7.5f;
GLdouble lightProjection[16],lightView[16];
GLfloat lightSpaceMatrix[16];
glOrtho(-10.0f, 10.0f, -10.0f, 10.0f, near_plane, far_plane);
glGetDoublev(GL_PROJECTION_MATRIX, lightProjection);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
gluLookAt(lightPos[0],lightPos[1],lightPos[2],0,0,0,0,1,0);
glGetDoublev(GL_MODELVIEW_MATRIX, lightView);
lightSpaceMatrix[16] = lightProjection[16]*lightView[16];
```

but it is incorrect,where is my wrong thanks

and error:Run-Time Check Failure #2 - Stack around the variable ‘lightSpaceMatrix’ was corrupted.