Fix indices not being offset to the bound vertex buffer when drawing indexed points in D3D9.

bug=angle:535

Change-Id: I5b86874cddbd3b90fe141e94085f5a4afb9f3db3
Reviewed-on: https://chromium-review.googlesource.com/179101
Reviewed-by: Shannon Woods <shannonwoods@chromium.org>
Tested-by: Shannon Woods <shannonwoods@chromium.org>
diff --git a/tests/angle_tests/IndexedPointsTest.cpp b/tests/angle_tests/IndexedPointsTest.cpp
new file mode 100644
index 0000000..3989482
--- /dev/null
+++ b/tests/angle_tests/IndexedPointsTest.cpp
@@ -0,0 +1,210 @@
+#include "ANGLETest.h"
+#include <array>
+
+template <typename IndexType, GLenum IndexTypeName>
+class IndexedPointsTest : public ANGLETest
+{
+protected:
+    IndexedPointsTest()
+    {
+        setWindowWidth(128);
+        setWindowHeight(128);
+        setConfigRedBits(8);
+        setConfigGreenBits(8);
+        setConfigBlueBits(8);
+        setConfigAlphaBits(8);
+        setConfigDepthBits(24);
+    }
+
+    float getIndexPositionX(size_t idx)
+    {
+        return (idx == 0 || idx == 3) ? -0.5f : 0.5f;
+    }
+
+    float getIndexPositionY(size_t idx)
+    {
+        return (idx == 2 || idx == 3) ? -0.5f : 0.5f;
+    }
+
+    virtual void SetUp()
+    {
+        ANGLETest::SetUp();
+
+        const std::string vertexShaderSource = SHADER_SOURCE
+        (
+            precision highp float;
+            attribute vec2 position;
+
+            void main()
+            {
+                gl_PointSize = 5.0;
+                gl_Position = vec4(position, 0.0, 1.0);
+            }
+        );
+
+        const std::string fragmentShaderSource = SHADER_SOURCE
+        (
+            precision highp float;
+
+            void main()
+            {
+                gl_FragColor = vec4(1.0, 0.0, 0.0, 1.0);
+            }
+        );
+
+        mProgram = compileProgram(vertexShaderSource, fragmentShaderSource);
+        if (mProgram == 0)
+        {
+            FAIL() << "shader compilation failed.";
+        }
+
+        std::array<GLfloat, mPointCount * 2> vertices =
+        {
+            getIndexPositionX(0), getIndexPositionY(0),
+            getIndexPositionX(1), getIndexPositionY(1),
+            getIndexPositionX(2), getIndexPositionY(2),
+            getIndexPositionX(3), getIndexPositionY(3),
+        };
+        glGenBuffers(1, &mVertexBuffer);
+        glBindBuffer(GL_ARRAY_BUFFER, mVertexBuffer);
+        glBufferData(GL_ARRAY_BUFFER, vertices.size() * sizeof(GLfloat), vertices.data(), GL_STATIC_DRAW);
+
+        std::array<IndexType, mPointCount> indices = { 0, 1, 2, 3 };
+        glGenBuffers(1, &mIndexBuffer);
+        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, mIndexBuffer);
+        glBufferData(GL_ELEMENT_ARRAY_BUFFER, indices.size() * sizeof(IndexType), indices.data(), GL_STATIC_DRAW);
+    }
+
+    virtual void TearDown()
+    {
+        glDeleteProgram(mProgram);
+
+        ANGLETest::TearDown();
+    }
+
+    void runTest(GLuint firstIndex)
+    {
+        glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
+        glClear(GL_COLOR_BUFFER_BIT);
+
+        GLint viewportSize[4];
+        glGetIntegerv(GL_VIEWPORT, viewportSize);
+
+        glBindBuffer(GL_ARRAY_BUFFER, mVertexBuffer);
+        GLint vertexLocation = glGetAttribLocation(mProgram, "position");
+        glVertexAttribPointer(vertexLocation, 2, GL_FLOAT, GL_FALSE, 0, 0);
+        glEnableVertexAttribArray(vertexLocation);
+
+        glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, mIndexBuffer);
+
+        glUseProgram(mProgram);
+
+        glDrawElements(GL_POINTS, mPointCount - firstIndex, IndexTypeName, reinterpret_cast<void*>(firstIndex * sizeof(IndexType)));
+
+        for (size_t i = 0; i < mPointCount; i++)
+        {
+            GLuint x = viewportSize[0] + (getIndexPositionX(i) * 0.5f + 0.5f) * (viewportSize[2] - viewportSize[0]);
+            GLuint y = viewportSize[1] + (getIndexPositionY(i) * 0.5f + 0.5f) * (viewportSize[3] - viewportSize[1]);
+
+            if (i < firstIndex)
+            {
+                EXPECT_PIXEL_EQ(x, y, 0, 0, 0, 255);
+            }
+            else
+            {
+                EXPECT_PIXEL_EQ(x, y, 255, 0, 0, 255);
+            }
+        }
+    }
+
+    GLuint mProgram;
+    GLuint mVertexBuffer;
+    GLuint mIndexBuffer;
+    static const GLuint mPointCount = 4;
+};
+
+typedef IndexedPointsTest<GLubyte, GL_UNSIGNED_BYTE> IndexedPointsTestUByte;
+
+TEST_F(IndexedPointsTestUByte, unsigned_byte_offset_0)
+{
+    runTest(0);
+}
+
+TEST_F(IndexedPointsTestUByte, unsigned_byte_offset_1)
+{
+    runTest(1);
+}
+
+TEST_F(IndexedPointsTestUByte, unsigned_byte_offset_2)
+{
+    runTest(2);
+}
+
+TEST_F(IndexedPointsTestUByte, unsigned_byte_offset_3)
+{
+    runTest(3);
+}
+
+typedef IndexedPointsTest<GLushort, GL_UNSIGNED_SHORT> IndexedPointsTestUShort;
+
+TEST_F(IndexedPointsTestUShort, unsigned_short_offset_0)
+{
+    runTest(0);
+}
+
+TEST_F(IndexedPointsTestUShort, unsigned_short_offset_1)
+{
+    runTest(1);
+}
+
+TEST_F(IndexedPointsTestUShort, unsigned_short_offset_2)
+{
+    runTest(2);
+}
+
+TEST_F(IndexedPointsTestUShort, unsigned_short_offset_3)
+{
+    runTest(3);
+}
+
+typedef IndexedPointsTest<GLuint, GL_UNSIGNED_INT> IndexedPointsTestUInt;
+
+TEST_F(IndexedPointsTestUInt, unsigned_int_offset_0)
+{
+    if (getClientVersion() < 3 && !extensionEnabled("GL_OES_element_index_uint"))
+    {
+        return;
+    }
+
+    runTest(0);
+}
+
+TEST_F(IndexedPointsTestUInt, unsigned_int_offset_1)
+{
+    if (getClientVersion() < 3 && !extensionEnabled("GL_OES_element_index_uint"))
+    {
+        return;
+    }
+
+    runTest(1);
+}
+
+TEST_F(IndexedPointsTestUInt, unsigned_int_offset_2)
+{
+    if (getClientVersion() < 3 && !extensionEnabled("GL_OES_element_index_uint"))
+    {
+        return;
+    }
+
+    runTest(2);
+}
+
+TEST_F(IndexedPointsTestUInt, unsigned_int_offset_3)
+{
+    if (getClientVersion() < 3 && !extensionEnabled("GL_OES_element_index_uint"))
+    {
+        return;
+    }
+
+    runTest(3);
+}