1 files changed, 29 insertions, 0 deletions
diff --git a/src/libultra_code_O2/ortho.c b/src/libultra_code_O2/ortho.c
new file mode 100644
index 000000000..70e64e9d2
--- /dev/null
+++ b/src/libultra_code_O2/ortho.c
@@ -0,0 +1,29 @@
+#include "global.h"
+
+void guOrthoF(f32 mf[4][4], f32 left, f32 right, f32 bottom, f32 top, f32 near, f32 far, f32 scale) {
+    s32 i, j;
+
+    guMtxIdentF(mf);
+
+    mf[0][0] = 2 / (right - left);
+    mf[1][1] = 2 / (top - bottom);
+    mf[2][2] = -2 / (far - near);
+    mf[3][0] = -(right + left) / (right - left);
+    mf[3][1] = -(top + bottom) / (top - bottom);
+    mf[3][2] = -(far + near) / (far - near);
+    mf[3][3] = 1;
+
+    for (i = 0; i < 4; i++) {
+        for (j = 0; j < 4; j++) {
+            mf[i][j] *= scale;
+        }
+    }
+}
+
+void guOrtho(Mtx* mtx, f32 left, f32 right, f32 bottom, f32 top, f32 near, f32 far, f32 scale) {
+    MtxF_t mf;
+
+    guOrthoF(mf, left, right, bottom, top, near, far, scale);
+
+    guMtxF2L(mf, mtx);
+}