From e2b4e483159d60968f97fe3964d5f6c5dec85557 Mon Sep 17 00:00:00 2001
From: Danny Robson <danny@nerdcruft.net>
Date: Wed, 14 Sep 2016 17:54:25 +1000
Subject: [PATCH] test: add matrix/quaternion consistency checks

---
 Makefile.am     |  1 +
 test/affine.cpp | 73 +++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 74 insertions(+)
 create mode 100644 test/affine.cpp

diff --git a/Makefile.am b/Makefile.am
index 4c356ba1..03ff8e33 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -385,6 +385,7 @@ TEST_BIN = 			\
     test/alloc/dynamic		\
     test/alloc/linear		\
     test/alloc/stack		\
+    test/affine			\
     test/backtrace 		\
     test/bezier			\
     test/bitwise		\
diff --git a/test/affine.cpp b/test/affine.cpp
new file mode 100644
index 00000000..66c3159a
--- /dev/null
+++ b/test/affine.cpp
@@ -0,0 +1,73 @@
+#include "tap.hpp"
+
+#include "vector.hpp"
+#include "matrix.hpp"
+#include "quaternion.hpp"
+
+
+///////////////////////////////////////////////////////////////////////////////
+void
+test_mq_axis (util::TAP::logger &tap)
+{
+    static const struct {
+        util::vector3f euler;
+        const char *msg;
+    } TESTS[] = {
+        { { 1, 0, 0 }, "x-axis" },
+        { { 0, 1, 0 }, "y-axis" },
+        { { 0, 0, 1 }, "z-axis" },
+    };
+
+    for (auto t: TESTS) {
+        auto m = util::matrix4f::rotation (1, t.euler);
+        auto q = util::quaternionf::rotation (1, t.euler);
+
+        auto diff = sum (abs (m - q.as_matrix ()));
+        tap.expect_le (diff, 1e-6f, "matrix/quaternion rotation identities, %s", t.msg);
+    }
+}
+
+
+///////////////////////////////////////////////////////////////////////////////
+void
+test_mq_euler (util::TAP::logger &tap)
+{
+    static const struct {
+        util::vector3f euler;
+        const char *msg;
+    } TESTS[] = {
+        { { 0, 0, 0 }, "zeroes" },
+        { { 1, 0, 0 }, "x-axis" },
+        { { 0, 1, 0 }, "y-axis" },
+        { { 0, 0, 1 }, "z-axis" },
+        { { 1, 1, 1 }, "ones"   },
+        { { 9, 9, 9 }, "nines"  }
+    };
+
+    for (auto t: TESTS) {
+        auto m = util::matrix4f::rotation (t.euler[0], { 1, 0, 0 }) *
+                 util::matrix4f::rotation (t.euler[1], { 0, 1, 0 }) *
+                 util::matrix4f::rotation (t.euler[2], { 0, 0, 1 });
+        auto q = (
+            util::quaternionf::rotation (t.euler[0], { 1, 0, 0 }) *
+            util::quaternionf::rotation (t.euler[1], { 0, 1, 0 }) *
+            util::quaternionf::rotation (t.euler[2], { 0, 0, 1 })
+        ).as_matrix ();
+
+        auto diff = util::sum (abs (m - q));
+        tap.expect_le (diff, 1e-6f, "matrix-quaternion xyz euler rotations, %s", t.msg);
+    }
+}
+
+
+///////////////////////////////////////////////////////////////////////////////
+int
+main (int, char**)
+{
+    util::TAP::logger tap;
+
+    test_mq_axis  (tap);
+    test_mq_euler (tap);
+
+    return tap.status ();
+}