From c39ef56db5b26f7bd9170ba2ee7168332bcbef9f Mon Sep 17 00:00:00 2001
From: Pierre Bourdon <delroth@gmail.com>
Date: Fri, 1 Aug 2014 23:42:36 -0700
Subject: [PATCH] VertexLoader: Add very basic unit testing to get started

---
 Source/UnitTests/CMakeLists.txt               |   1 +
 Source/UnitTests/VideoCommon/CMakeLists.txt   |   1 +
 .../VideoCommon/VertexLoaderTest.cpp          | 110 ++++++++++++++++++
 3 files changed, 112 insertions(+)
 create mode 100644 Source/UnitTests/VideoCommon/CMakeLists.txt
 create mode 100644 Source/UnitTests/VideoCommon/VertexLoaderTest.cpp

diff --git a/Source/UnitTests/CMakeLists.txt b/Source/UnitTests/CMakeLists.txt
index fc896f4e1b..104b1836ab 100644
--- a/Source/UnitTests/CMakeLists.txt
+++ b/Source/UnitTests/CMakeLists.txt
@@ -17,3 +17,4 @@ add_subdirectory(TestUtils)
 
 add_subdirectory(Common)
 add_subdirectory(Core)
+add_subdirectory(VideoCommon)
diff --git a/Source/UnitTests/VideoCommon/CMakeLists.txt b/Source/UnitTests/VideoCommon/CMakeLists.txt
new file mode 100644
index 0000000000..b5198536ed
--- /dev/null
+++ b/Source/UnitTests/VideoCommon/CMakeLists.txt
@@ -0,0 +1 @@
+add_dolphin_test(VertexLoaderTest VertexLoaderTest.cpp)
diff --git a/Source/UnitTests/VideoCommon/VertexLoaderTest.cpp b/Source/UnitTests/VideoCommon/VertexLoaderTest.cpp
new file mode 100644
index 0000000000..c529a628e6
--- /dev/null
+++ b/Source/UnitTests/VideoCommon/VertexLoaderTest.cpp
@@ -0,0 +1,110 @@
+#include <set>
+
+#include "Common/Common.h"
+#include "VideoCommon/DataReader.h"
+#include "VideoCommon/VertexLoader.h"
+
+// Needs to be included later because it defines a TEST macro that conflicts
+// with a TEST method definition in x64Emitter.h.
+#include <gtest/gtest.h>  // NOLINT
+
+TEST(VertexLoaderUID, UniqueEnough)
+{
+	std::set<VertexLoaderUID> uids;
+
+	TVtxDesc vtx_desc;
+	VAT vat;
+	uids.insert(VertexLoaderUID(vtx_desc, vat));
+
+	vtx_desc.Hex = 0xFEDCBA9876543210ull;
+	EXPECT_EQ(uids.end(), uids.find(VertexLoaderUID(vtx_desc, vat)));
+	uids.insert(VertexLoaderUID(vtx_desc, vat));
+
+	vat.g0.Hex = 0xFFFFFFFF;
+	vat.g1.Hex = 0xFFFFFFFF;
+	vat.g2.Hex = 0xFFFFFFFF;
+	EXPECT_EQ(uids.end(), uids.find(VertexLoaderUID(vtx_desc, vat)));
+	uids.insert(VertexLoaderUID(vtx_desc, vat));
+}
+
+class VertexLoaderTest : public testing::Test
+{
+protected:
+	void SetUp() override
+	{
+		// The vertex loading code is still using global variables to specify
+		// where to load and store data.
+		//
+		// Reserve 64K of memory for both.
+		m_input_memory.clear(); m_input_memory.resize(65536);
+		m_output_memory.clear(); m_output_memory.resize(65536);
+		g_pVideoData = m_input_memory.data();
+		VertexManager::s_pCurBufferPointer = m_output_memory.data();
+
+		m_input_pos = m_output_pos = 0;
+	}
+
+	// Pushes a value to the input stream.
+	template <typename T>
+	void Input(T val)
+	{
+		// Converts *to* big endian, not from.
+		*(T*)(&m_input_memory[m_input_pos]) = Common::FromBigEndian(val);
+		m_input_pos += sizeof (val);
+	}
+
+	// Reads a value from the output stream.
+	template <typename T>
+	T Output()
+	{
+		T out = *(T*)&m_output_memory[m_output_pos];
+		m_output_pos += sizeof (out);
+		return out;
+	}
+
+	u32 m_input_pos, m_output_pos;
+	std::vector<u8> m_input_memory, m_output_memory;
+};
+
+TEST_F(VertexLoaderTest, PositionDirectXYZ)
+{
+	TVtxDesc vtx_desc;
+	VAT vtx_attr;
+
+	memset(&vtx_desc, 0, sizeof (vtx_desc));
+	memset(&vtx_attr, 0, sizeof (vtx_attr));
+
+	vtx_desc.Position = 1;        // Direct.
+	vtx_attr.g0.PosElements = 1;  // XYZ
+	vtx_attr.g0.PosFormat = 4;    // Float
+
+	VertexLoader loader(vtx_desc, vtx_attr);
+
+	ASSERT_EQ(3 * sizeof (float), (u32)loader.GetNativeVertexDeclaration().stride);
+	ASSERT_EQ(3 * sizeof (float), (u32)loader.GetVertexSize());
+
+	// Write some vertices.
+	Input(0.0f); Input(0.0f); Input(0.0f);
+	Input(1.0f); Input(0.0f); Input(0.0f);
+	Input(0.0f); Input(1.0f); Input(0.0f);
+	Input(0.0f); Input(0.0f); Input(1.0f);
+
+	// Convert 4 points. "7" -> primitive are points.
+	loader.RunVertices(vtx_attr, 7, 4);
+
+	EXPECT_EQ(0.0f, Output<float>());
+	EXPECT_EQ(0.0f, Output<float>());
+	EXPECT_EQ(0.0f, Output<float>());
+
+	EXPECT_EQ(1.0f, Output<float>());
+	EXPECT_EQ(0.0f, Output<float>());
+	EXPECT_EQ(0.0f, Output<float>());
+
+	EXPECT_EQ(0.0f, Output<float>());
+	EXPECT_EQ(1.0f, Output<float>());
+	EXPECT_EQ(0.0f, Output<float>());
+
+	EXPECT_EQ(0.0f, Output<float>());
+	EXPECT_EQ(0.0f, Output<float>());
+	EXPECT_EQ(1.0f, Output<float>());
+}