Added emulated indexed pointsprite rendering support.

This emulation is for renderers that do not support Geometry Shaders.

BUG=angleproject:949

Change-Id: I7acf003e83ea6661f10a703486e6d07eb28786f8
Reviewed-on: https://chromium-review.googlesource.com/274851
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Tested-by: Cooper Partin <coopp@microsoft.com>
diff --git a/src/tests/gl_tests/IndexedPointsTest.cpp b/src/tests/gl_tests/IndexedPointsTest.cpp
index 190d965..af59eb5 100644
--- a/src/tests/gl_tests/IndexedPointsTest.cpp
+++ b/src/tests/gl_tests/IndexedPointsTest.cpp
@@ -60,23 +60,64 @@
         );
 
         mProgram = CompileProgram(vertexShaderSource, fragmentShaderSource);
-        if (mProgram == 0)
-        {
-            FAIL() << "shader compilation failed.";
-        }
+        ASSERT_NE(0u, mProgram);
 
+        const std::string vertexShaderSource2 = SHADER_SOURCE
+        (
+            precision highp float;
+            attribute vec2 position;
+            attribute vec4 color;
+            varying vec4 vcolor;
+
+            void main()
+            {
+                gl_PointSize = 5.0;
+                gl_Position = vec4(position, 0.0, 1.0);
+                vcolor = color;
+            }
+        );
+
+        const std::string fragmentShaderSource2 = SHADER_SOURCE
+        (
+            precision highp float;
+            varying vec4 vcolor;
+            void main()
+            {
+                gl_FragColor = vec4(vcolor.xyz, 1.0);
+            }
+        );
+
+        mVertexWithColorBufferProgram = CompileProgram(vertexShaderSource2, fragmentShaderSource2);
+        ASSERT_NE(0u, mVertexWithColorBufferProgram);
+
+        // Construct a vertex buffer of position values and color values
+        // contained in a single structure
+        const float verticesWithColor[] =
+        {
+            getIndexPositionX(0), getIndexPositionY(0), 0.0f, 1.0f, 0.0f,
+            getIndexPositionX(2), getIndexPositionY(2), 0.0f, 1.0f, 0.0f,
+            getIndexPositionX(1), getIndexPositionY(1), 0.0f, 1.0f, 0.0f,
+            getIndexPositionX(3), getIndexPositionY(3), 0.0f, 1.0f, 0.0f,
+        };
+
+        glGenBuffers(1, &mVertexWithColorBuffer);
+        glBindBuffer(GL_ARRAY_BUFFER, mVertexWithColorBuffer);
+        glBufferData(GL_ARRAY_BUFFER, sizeof(verticesWithColor), &verticesWithColor[0], GL_STATIC_DRAW);
+
+        // Construct a vertex buffer of position values only
         const GLfloat vertices[] =
         {
             getIndexPositionX(0), getIndexPositionY(0),
-            getIndexPositionX(1), getIndexPositionY(1),
             getIndexPositionX(2), getIndexPositionY(2),
+            getIndexPositionX(1), getIndexPositionY(1),
             getIndexPositionX(3), getIndexPositionY(3),
         };
         glGenBuffers(1, &mVertexBuffer);
         glBindBuffer(GL_ARRAY_BUFFER, mVertexBuffer);
         glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), &vertices[0], GL_STATIC_DRAW);
 
-        const IndexType indices[] = { 0, 1, 2, 3 };
+        // The indices buffer is shared between both variations of tests
+        const IndexType indices[] = { 0, 2, 1, 3 };
         glGenBuffers(1, &mIndexBuffer);
         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, mIndexBuffer);
         glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(indices), &indices[0], GL_STATIC_DRAW);
@@ -84,12 +125,16 @@
 
     virtual void TearDown()
     {
+        glDeleteBuffers(1, &mVertexBuffer);
+        glDeleteBuffers(1, &mIndexBuffer);
         glDeleteProgram(mProgram);
 
+        glDeleteBuffers(1, &mVertexWithColorBuffer);
+        glDeleteProgram(mVertexWithColorBufferProgram);
         ANGLETest::TearDown();
     }
 
-    void runTest(GLuint firstIndex)
+    void runTest(GLuint firstIndex, bool useVertexBufferWithColor = false)
     {
         glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
         glClear(GL_COLOR_BUFFER_BIT);
@@ -97,14 +142,30 @@
         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);
+        // Choose appropriate program to apply for the test
+        GLuint program = useVertexBufferWithColor ? mVertexWithColorBufferProgram : mProgram;
+
+        if (useVertexBufferWithColor)
+        {
+            glBindBuffer(GL_ARRAY_BUFFER, mVertexWithColorBuffer);
+            GLint vertexLocation = glGetAttribLocation(program, "position");
+            glVertexAttribPointer(vertexLocation, 2, GL_FLOAT, GL_FALSE, VertexWithColorSize, 0);
+            glEnableVertexAttribArray(vertexLocation);
+
+            GLint vertexColorLocation = glGetAttribLocation(program, "color");
+            glVertexAttribPointer(vertexColorLocation, 3, GL_FLOAT, GL_FALSE, VertexWithColorSize, (GLvoid*)((sizeof(float) * 2)));
+            glEnableVertexAttribArray(vertexColorLocation);
+        }
+        else
+        {
+            glBindBuffer(GL_ARRAY_BUFFER, mVertexBuffer);
+            GLint vertexLocation = glGetAttribLocation(program, "position");
+            glVertexAttribPointer(vertexLocation, 2, GL_FLOAT, GL_FALSE, 0, 0);
+            glEnableVertexAttribArray(vertexLocation);
+        }
 
         glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, mIndexBuffer);
-
-        glUseProgram(mProgram);
+        glUseProgram(program);
 
         glDrawElements(GL_POINTS, mPointCount - firstIndex, IndexTypeName, reinterpret_cast<void*>(firstIndex * sizeof(IndexType)));
 
@@ -119,15 +180,32 @@
             }
             else
             {
-                EXPECT_PIXEL_EQ(x, y, 255, 0, 0, 255);
+                if (useVertexBufferWithColor)
+                {
+                    // Pixel data is assumed to be GREEN
+                    EXPECT_PIXEL_EQ(x, y, 0, 255, 0, 255);
+                }
+                else
+                {
+                    // Pixel data is assumed to be RED
+                    EXPECT_PIXEL_EQ(x, y, 255, 0, 0, 255);
+                }
             }
         }
+        swapBuffers();
     }
 
     GLuint mProgram;
     GLuint mVertexBuffer;
     GLuint mIndexBuffer;
+
+    GLuint mVertexWithColorBufferProgram;
+    GLuint mVertexWithColorBuffer;
+
     static const GLuint mPointCount = 4;
+
+  private:
+    const size_t VertexWithColorSize = sizeof(float) * 5;
 };
 
 typedef IndexedPointsTest<GLubyte, GL_UNSIGNED_BYTE> IndexedPointsTestUByte;
@@ -152,6 +230,26 @@
     runTest(3);
 }
 
+TEST_P(IndexedPointsTestUByte, VertexWithColorUnsignedByteOffset0)
+{
+    runTest(0, true);
+}
+
+TEST_P(IndexedPointsTestUByte, VertexWithColorUnsignedByteOffset1)
+{
+    runTest(1, true);
+}
+
+TEST_P(IndexedPointsTestUByte, VertexWithColorUnsignedByteOffset2)
+{
+    runTest(2, true);
+}
+
+TEST_P(IndexedPointsTestUByte, VertexWithColorUnsignedByteOffset3)
+{
+    runTest(3, true);
+}
+
 typedef IndexedPointsTest<GLushort, GL_UNSIGNED_SHORT> IndexedPointsTestUShort;
 
 TEST_P(IndexedPointsTestUShort, UnsignedShortOffset0)
@@ -174,6 +272,34 @@
     runTest(3);
 }
 
+TEST_P(IndexedPointsTestUShort, VertexWithColorUnsignedShortOffset0)
+{
+    runTest(0, true);
+}
+
+TEST_P(IndexedPointsTestUShort, VertexWithColorUnsignedShortOffset1)
+{
+    runTest(1, true);
+}
+
+TEST_P(IndexedPointsTestUShort, VertexWithColorUnsignedShortOffset2)
+{
+    runTest(2, true);
+}
+
+TEST_P(IndexedPointsTestUShort, VertexWithColorUnsignedShortOffset3)
+{
+    runTest(3, true);
+}
+
+TEST_P(IndexedPointsTestUShort, VertexWithColorUnsignedShortOffsetChangingIndices)
+{
+    runTest(3, true);
+    runTest(1, true);
+    runTest(0, true);
+    runTest(2, true);
+}
+
 typedef IndexedPointsTest<GLuint, GL_UNSIGNED_INT> IndexedPointsTestUInt;
 
 TEST_P(IndexedPointsTestUInt, UnsignedIntOffset0)
@@ -216,7 +342,47 @@
     runTest(3);
 }
 
+TEST_P(IndexedPointsTestUInt, VertexWithColorUnsignedIntOffset0)
+{
+    if (getClientVersion() < 3 && !extensionEnabled("GL_OES_element_index_uint"))
+    {
+        return;
+    }
+
+    runTest(0, false);
+}
+
+TEST_P(IndexedPointsTestUInt, VertexWithColorUnsignedIntOffset1)
+{
+    if (getClientVersion() < 3 && !extensionEnabled("GL_OES_element_index_uint"))
+    {
+        return;
+    }
+
+    runTest(1, false);
+}
+
+TEST_P(IndexedPointsTestUInt, VertexWithColorUnsignedIntOffset2)
+{
+    if (getClientVersion() < 3 && !extensionEnabled("GL_OES_element_index_uint"))
+    {
+        return;
+    }
+
+    runTest(2, false);
+}
+
+TEST_P(IndexedPointsTestUInt, VertexWithColorUnsignedIntOffset3)
+{
+    if (getClientVersion() < 3 && !extensionEnabled("GL_OES_element_index_uint"))
+    {
+        return;
+    }
+
+    runTest(3, false);
+}
+
 // TODO(geofflang): Figure out why this test fails on Intel OpenGL
-ANGLE_INSTANTIATE_TEST(IndexedPointsTestUByte, ES2_D3D11());
-ANGLE_INSTANTIATE_TEST(IndexedPointsTestUShort, ES2_D3D11());
-ANGLE_INSTANTIATE_TEST(IndexedPointsTestUInt, ES2_D3D11());
+ANGLE_INSTANTIATE_TEST(IndexedPointsTestUByte, ES2_D3D11(), ES2_D3D11_FL9_3());
+ANGLE_INSTANTIATE_TEST(IndexedPointsTestUShort, ES2_D3D11(), ES2_D3D11_FL9_3());
+ANGLE_INSTANTIATE_TEST(IndexedPointsTestUInt, ES2_D3D11(), ES2_D3D11_FL9_3());