vector and matrix classes for graphics use

- this implements vec2, vec3, vec4, which are float vectors
of size 2, 3 and 4 respectively.

the code allows easy instantiation of vectors of a different
type via the tvec{2|3|4}<T> template classes.

- this also implements mat4 which is a float 4x4 matrix. the
tmat44<T> template class allows easy instantiation of a
4x4 matrix of a different value_type.

The vector types have some minimal support for the
glsl style swizzled access; for instance:

  vec4 u;
  vec3 v = u.xyz;

only .x, .xy, .xyz and their .stpq / .rgba equivalent are
supported.

most operators are supported on both vector and matrices:
arithmetic, unary, compound assignment and comparison
(bit-wise operators NOT supported).

- operations available on vectors include:
dot, length, distance, normalize and cross

- operations available on matrices include:
transpose, inverse, trace

- and a few utilities to create matrices:
ortho, frustum, lookAt

Change-Id: I64add89ae90fa78d3f2f59985b63495575378635
diff --git a/libs/ui/tests/mat_test.cpp b/libs/ui/tests/mat_test.cpp
new file mode 100644
index 0000000..a2c63ac
--- /dev/null
+++ b/libs/ui/tests/mat_test.cpp
@@ -0,0 +1,139 @@
+/*
+ * Copyright 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define LOG_TAG "RegionTest"
+
+#include <stdlib.h>
+#include <ui/Region.h>
+#include <ui/Rect.h>
+#include <gtest/gtest.h>
+
+#include <ui/mat4.h>
+
+namespace android {
+
+class MatTest : public testing::Test {
+protected:
+};
+
+TEST_F(MatTest, Basics) {
+    mat4 m0;
+    EXPECT_EQ(sizeof(mat4), sizeof(float)*16);
+}
+
+TEST_F(MatTest, ComparisonOps) {
+    mat4 m0;
+    mat4 m1(2);
+
+    EXPECT_TRUE(m0 == m0);
+    EXPECT_TRUE(m0 != m1);
+    EXPECT_FALSE(m0 != m0);
+    EXPECT_FALSE(m0 == m1);
+}
+
+TEST_F(MatTest, Constructors) {
+    mat4 m0;
+    ASSERT_EQ(m0[0].x, 1);
+    ASSERT_EQ(m0[0].y, 0);
+    ASSERT_EQ(m0[0].z, 0);
+    ASSERT_EQ(m0[0].w, 0);
+    ASSERT_EQ(m0[1].x, 0);
+    ASSERT_EQ(m0[1].y, 1);
+    ASSERT_EQ(m0[1].z, 0);
+    ASSERT_EQ(m0[1].w, 0);
+    ASSERT_EQ(m0[2].x, 0);
+    ASSERT_EQ(m0[2].y, 0);
+    ASSERT_EQ(m0[2].z, 1);
+    ASSERT_EQ(m0[2].w, 0);
+    ASSERT_EQ(m0[3].x, 0);
+    ASSERT_EQ(m0[3].y, 0);
+    ASSERT_EQ(m0[3].z, 0);
+    ASSERT_EQ(m0[3].w, 1);
+
+    mat4 m1(2);
+    mat4 m2(vec4(2));
+    mat4 m3(m2);
+
+    EXPECT_EQ(m1, m2);
+    EXPECT_EQ(m2, m3);
+    EXPECT_EQ(m3, m1);
+
+    mat4 m4(vec4(1), vec4(2), vec4(3), vec4(4));
+}
+
+TEST_F(MatTest, ArithmeticOps) {
+    mat4 m0;
+    mat4 m1(2);
+    mat4 m2(vec4(2));
+
+    m1 += m2;
+    EXPECT_EQ(mat4(4), m1);
+
+    m2 -= m1;
+    EXPECT_EQ(mat4(-2), m2);
+
+    m1 *= 2;
+    EXPECT_EQ(mat4(8), m1);
+
+    m1 /= 2;
+    EXPECT_EQ(mat4(4), m1);
+
+    m0 = -m0;
+    EXPECT_EQ(mat4(-1), m0);
+}
+
+TEST_F(MatTest, UnaryOps) {
+    const mat4 identity;
+    mat4 m0;
+
+    ++m0;
+    EXPECT_EQ(mat4( vec4(2,1,1,1), vec4(1,2,1,1), vec4(1,1,2,1), vec4(1,1,1,2) ), m0);
+    EXPECT_EQ(mat4( -vec4(2,1,1,1), -vec4(1,2,1,1), -vec4(1,1,2,1), -vec4(1,1,1,2) ), -m0);
+
+    --m0;
+    EXPECT_EQ(identity, m0);
+}
+
+TEST_F(MatTest, MiscOps) {
+    const mat4 identity;
+    mat4 m0;
+    EXPECT_EQ(4, trace(m0));
+
+    mat4 m1(vec4(1,2,3,4), vec4(5,6,7,8), vec4(9,10,11,12), vec4(13,14,15,16));
+    mat4 m2(vec4(1,5,9,13), vec4(2,6,10,14), vec4(3,7,11,15), vec4(4,8,12,16));
+    EXPECT_EQ(m1, transpose(m2));
+    EXPECT_EQ(m2, transpose(m1));
+    EXPECT_EQ(vec4(1,6,11,16), diag(m1));
+
+    EXPECT_EQ(identity, inverse(identity));
+
+    mat4 m3(vec4(4,3,0,0), vec4(3,2,0,0), vec4(0,0,1,0), vec4(0,0,0,1));
+    mat4 m3i(inverse(m3));
+    EXPECT_FLOAT_EQ(-2, m3i[0][0]);
+    EXPECT_FLOAT_EQ( 3, m3i[0][1]);
+    EXPECT_FLOAT_EQ( 3, m3i[1][0]);
+    EXPECT_FLOAT_EQ(-4, m3i[1][1]);
+
+    mat4 m3ii(inverse(m3i));
+    EXPECT_FLOAT_EQ(m3[0][0], m3ii[0][0]);
+    EXPECT_FLOAT_EQ(m3[0][1], m3ii[0][1]);
+    EXPECT_FLOAT_EQ(m3[1][0], m3ii[1][0]);
+    EXPECT_FLOAT_EQ(m3[1][1], m3ii[1][1]);
+
+    EXPECT_EQ(m1, m1*identity);
+}
+
+}; // namespace android