Support creating default texture view on 2D array textures

This patch intends to implement creating default texture view on
2D array textures.

BUG=dawn:16

Change-Id: I4321c9506b2e875146645ad60291196dcfcc8ea0
Reviewed-on: https://dawn-review.googlesource.com/c/1660
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
Commit-Queue: Jiawei Shao <jiawei.shao@intel.com>
diff --git a/BUILD.gn b/BUILD.gn
index 8b8066f..1419563 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -688,8 +688,8 @@
     ":dawn_common",
     ":libdawn_native",
     ":libdawn_wire",
-    "third_party:glfw",
     "${dawn_shaderc_dir}:libshaderc",
+    "third_party:glfw",
   ]
   libs = []
 
@@ -822,6 +822,7 @@
     "src/tests/end2end/RenderPassLoadOpTests.cpp",
     "src/tests/end2end/SamplerTests.cpp",
     "src/tests/end2end/ScissorTests.cpp",
+    "src/tests/end2end/TextureViewTests.cpp",
     "src/tests/end2end/ViewportOrientationTests.cpp",
   ]
 }
diff --git a/src/dawn_native/d3d12/TextureD3D12.cpp b/src/dawn_native/d3d12/TextureD3D12.cpp
index 205f5cf..a7d0a78 100644
--- a/src/dawn_native/d3d12/TextureD3D12.cpp
+++ b/src/dawn_native/d3d12/TextureD3D12.cpp
@@ -192,12 +192,25 @@
         mSrvDesc.Shader4ComponentMapping = D3D12_DEFAULT_SHADER_4_COMPONENT_MAPPING;
         switch (GetTexture()->GetDimension()) {
             case dawn::TextureDimension::e2D:
-                mSrvDesc.ViewDimension = D3D12_SRV_DIMENSION_TEXTURE2D;
-                mSrvDesc.Texture2D.MostDetailedMip = 0;
-                mSrvDesc.Texture2D.MipLevels = GetTexture()->GetNumMipLevels();
-                mSrvDesc.Texture2D.PlaneSlice = 0;
-                mSrvDesc.Texture2D.ResourceMinLODClamp = 0;
+                if (GetTexture()->GetArrayLayers() == 1) {
+                    mSrvDesc.ViewDimension = D3D12_SRV_DIMENSION_TEXTURE2D;
+                    mSrvDesc.Texture2D.MostDetailedMip = 0;
+                    mSrvDesc.Texture2D.MipLevels = GetTexture()->GetNumMipLevels();
+                    mSrvDesc.Texture2D.PlaneSlice = 0;
+                    mSrvDesc.Texture2D.ResourceMinLODClamp = 0;
+                } else {
+                    mSrvDesc.ViewDimension = D3D12_SRV_DIMENSION_TEXTURE2DARRAY;
+                    mSrvDesc.Texture2DArray.ArraySize = GetTexture()->GetArrayLayers();
+                    mSrvDesc.Texture2DArray.FirstArraySlice = 0;
+                    mSrvDesc.Texture2DArray.MipLevels = GetTexture()->GetNumMipLevels();
+                    mSrvDesc.Texture2DArray.MostDetailedMip = 0;
+                    mSrvDesc.Texture2DArray.PlaneSlice = 0;
+                    mSrvDesc.Texture2DArray.ResourceMinLODClamp = 0;
+                }
                 break;
+
+            default:
+                UNREACHABLE();
         }
     }
 
diff --git a/src/dawn_native/vulkan/TextureVk.cpp b/src/dawn_native/vulkan/TextureVk.cpp
index 11521a3..6826e19 100644
--- a/src/dawn_native/vulkan/TextureVk.cpp
+++ b/src/dawn_native/vulkan/TextureVk.cpp
@@ -362,7 +362,7 @@
         createInfo.subresourceRange.baseMipLevel = 0;
         createInfo.subresourceRange.levelCount = GetTexture()->GetNumMipLevels();
         createInfo.subresourceRange.baseArrayLayer = 0;
-        createInfo.subresourceRange.layerCount = 1;
+        createInfo.subresourceRange.layerCount = GetTexture()->GetArrayLayers();
 
         if (device->fn.CreateImageView(device->GetVkDevice(), &createInfo, nullptr, &mHandle) !=
             VK_SUCCESS) {
diff --git a/src/tests/end2end/TextureViewTests.cpp b/src/tests/end2end/TextureViewTests.cpp
new file mode 100644
index 0000000..860325b
--- /dev/null
+++ b/src/tests/end2end/TextureViewTests.cpp
@@ -0,0 +1,165 @@
+// Copyright 2018 The Dawn Authors
+//
+// 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.
+
+#include "tests/DawnTest.h"
+
+#include "common/Assert.h"
+#include "common/Constants.h"
+#include "utils/DawnHelpers.h"
+
+constexpr static unsigned int kRTSize = 64;
+
+class TextureViewTest : public DawnTest {
+protected:
+    void SetUp() override {
+        DawnTest::SetUp();
+
+        mRenderPass = utils::CreateBasicRenderPass(device, kRTSize, kRTSize);
+
+        mBindGroupLayout = utils::MakeBindGroupLayout(
+            device, {
+                        {0, dawn::ShaderStageBit::Fragment, dawn::BindingType::Sampler},
+                        {1, dawn::ShaderStageBit::Fragment, dawn::BindingType::SampledTexture},
+            });
+
+        dawn::FilterMode kFilterMode = dawn::FilterMode::Nearest;
+        dawn::AddressMode kAddressMode = dawn::AddressMode::ClampToEdge;
+
+        dawn::SamplerDescriptor samplerDescriptor;
+        samplerDescriptor.minFilter = kFilterMode;
+        samplerDescriptor.magFilter = kFilterMode;
+        samplerDescriptor.mipmapFilter = kFilterMode;
+        samplerDescriptor.addressModeU = kAddressMode;
+        samplerDescriptor.addressModeV = kAddressMode;
+        samplerDescriptor.addressModeW = kAddressMode;
+        mSampler = device.CreateSampler(&samplerDescriptor);
+
+        mPipelineLayout = utils::MakeBasicPipelineLayout(device, &mBindGroupLayout);
+
+        mVSModule = utils::CreateShaderModule(device, dawn::ShaderStage::Vertex, R"(
+            #version 450
+            void main() {
+                const vec2 pos[6] = vec2[6](vec2(-2.f, -2.f),
+                                            vec2(-2.f,  2.f),
+                                            vec2( 2.f, -2.f),
+                                            vec2(-2.f,  2.f),
+                                            vec2( 2.f, -2.f),
+                                            vec2( 2.f,  2.f));
+                gl_Position = vec4(pos[gl_VertexIndex], 0.f, 1.f);
+            }
+        )");
+    }
+
+    void initTexture(uint32_t layerCount) {
+        ASSERT(layerCount > 0);
+
+        dawn::TextureDescriptor descriptor;
+        descriptor.dimension = dawn::TextureDimension::e2D;
+        descriptor.size.width = 2;
+        descriptor.size.height = 2;
+        descriptor.size.depth = 1;
+        descriptor.arrayLayer = layerCount;
+        descriptor.format = dawn::TextureFormat::R8G8B8A8Unorm;
+        descriptor.mipLevel = 1;
+        descriptor.usage = dawn::TextureUsageBit::TransferDst | dawn::TextureUsageBit::Sampled;
+        mTexture = device.CreateTexture(&descriptor);
+
+        // Create a 2x2 checkerboard texture, with black in the top left and bottom right corners.
+        constexpr uint32_t kRowPixels = kTextureRowPitchAlignment / sizeof(RGBA8);
+
+        dawn::CommandBufferBuilder builder = device.CreateCommandBufferBuilder();
+        for (uint32_t layer = 0; layer < layerCount; ++layer) {
+            RGBA8 data[kRowPixels * 2];
+            int pixelValue = static_cast<int>(layer);
+            data[0] = data[kRowPixels + 1] = RGBA8(0, 0, 0, pixelValue);
+            data[1] = data[kRowPixels] = RGBA8(pixelValue, pixelValue, pixelValue, pixelValue);;
+            dawn::Buffer stagingBuffer = utils::CreateBufferFromData(
+                device, data, sizeof(data), dawn::BufferUsageBit::TransferSrc);
+            builder.CopyBufferToTexture(
+                stagingBuffer, 0, 256, mTexture, 0, 0, 0, 2, 2, 1, 0, layer);
+        }
+        dawn::CommandBuffer copy = builder.GetResult();
+        queue.Submit(1, &copy);
+    }
+
+    void Test(const dawn::TextureView &textureView, const char* fragmentShader, int expected) {
+        dawn::BindGroup bindGroup = device.CreateBindGroupBuilder()
+            .SetLayout(mBindGroupLayout)
+            .SetSamplers(0, 1, &mSampler)
+            .SetTextureViews(1, 1, &textureView)
+            .GetResult();
+
+        dawn::ShaderModule fsModule =
+            utils::CreateShaderModule(device, dawn::ShaderStage::Fragment, fragmentShader);
+
+        dawn::RenderPipeline pipeline = device.CreateRenderPipelineBuilder()
+            .SetColorAttachmentFormat(0, mRenderPass.colorFormat)
+            .SetLayout(mPipelineLayout)
+            .SetStage(dawn::ShaderStage::Vertex, mVSModule, "main")
+            .SetStage(dawn::ShaderStage::Fragment, fsModule, "main")
+            .GetResult();
+
+        dawn::CommandBufferBuilder builder = device.CreateCommandBufferBuilder();
+        {
+            dawn::RenderPassEncoder pass = builder.BeginRenderPass(mRenderPass.renderPassInfo);
+            pass.SetRenderPipeline(pipeline);
+            pass.SetBindGroup(0, bindGroup);
+            pass.DrawArrays(6, 1, 0, 0);
+            pass.EndPass();
+        }
+
+        dawn::CommandBuffer commands = builder.GetResult();
+        queue.Submit(1, &commands);
+
+        RGBA8 expectedPixel0(0, 0, 0, expected);
+        RGBA8 expectedPixel1(expected, expected, expected, expected);
+        EXPECT_PIXEL_RGBA8_EQ(expectedPixel0, mRenderPass.color, 0, 0);
+        EXPECT_PIXEL_RGBA8_EQ(expectedPixel1, mRenderPass.color, 0, 1);
+        EXPECT_PIXEL_RGBA8_EQ(expectedPixel1, mRenderPass.color, 1, 0);
+        EXPECT_PIXEL_RGBA8_EQ(expectedPixel0, mRenderPass.color, 1, 1);
+        // TODO(jiawei.shao@intel.com): add tests for 3D textures once Dawn supports 3D textures
+    }
+
+    dawn::BindGroupLayout mBindGroupLayout;
+    dawn::PipelineLayout mPipelineLayout;
+    dawn::Sampler mSampler;
+    dawn::Texture mTexture;
+    dawn::ShaderModule mVSModule;
+    utils::BasicRenderPass mRenderPass;
+};
+
+// Test drawing a rect with a checkerboard 2D array texture.
+TEST_P(TextureViewTest, Default2DArrayTexture) {
+    constexpr uint32_t kLayers = 3;
+    initTexture(kLayers);
+
+    dawn::TextureView textureView = mTexture.CreateDefaultTextureView();
+
+    const char* fragmentShader = R"(
+            #version 450
+            layout(set = 0, binding = 0) uniform sampler sampler0;
+            layout(set = 0, binding = 1) uniform texture2DArray texture0;
+            layout(location = 0) out vec4 fragColor;
+
+            void main() {
+                fragColor =
+                    texture(sampler2DArray(texture0, sampler0), vec3(gl_FragCoord.xy / 2.0, 0)) +
+                    texture(sampler2DArray(texture0, sampler0), vec3(gl_FragCoord.xy / 2.0, 1)) +
+                    texture(sampler2DArray(texture0, sampler0), vec3(gl_FragCoord.xy / 2.0, 2));
+            }
+        )";
+    Test(textureView, fragmentShader, kLayers);
+}
+
+DAWN_INSTANTIATE_TEST(TextureViewTest, D3D12Backend, MetalBackend, OpenGLBackend, VulkanBackend)