refactored coordinate system setting.

1 files changed, 18 insertions, 0 deletions

diff --git a/graphics/coordinates.cpp b/graphics/coordinates.cpp
new file mode 100644
index 0000000000..c26babb775
--- /dev/null
+++ b/graphics/coordinates.cpp
@@ -0,0 +1,18 @@
+#include "coordinates.hpp"
+
+namespace graphics
+{
+  void getOrthoMatrix(math::Matrix<float, 4, 4> & m,
+                      float l,
+                      float r,
+                      float b,
+                      float t,
+                      float n,
+                      float f)
+  {
+    m(0, 0) = 2 / (r - l); m(0, 1) = 0;          m(0, 2) = 0;            m(0, 3) = -(r + l) / (r - l);
+    m(1, 0) = 0;           m(1, 1) = 2 / (t - b);m(1, 2) = 0;            m(1, 3) = -(t + b) / (t - b);
+    m(2, 0) = 0;           m(2, 1) = 0;          m(2, 2) = -2 / (f - n); m(2, 3) = - (f + n) / (f - n);
+    m(3, 0) = 0;           m(3, 1) = 0;          m(3, 2) = 0;            m(3, 3) = 1;
+  }
+}