Vulkan: Fix texture copy from texture3d to texture2d or cubemap

src/libANGLE/renderer/vulkan/TextureVk.cpp

@@ -103,6 +103,14 @@ void GetRenderTargetLayerCountAndIndex(vk::ImageHelper *image,
             UNREACHABLE();
     }
 }
+
+void Set3DBaseArrayLayerAndLayerCount(VkImageSubresourceLayers *Subresource)
+{
+    // If the srcImage/dstImage parameters are of VkImageType VK_IMAGE_TYPE_3D, the baseArrayLayer
+    // and layerCount members of the corresponding subresource must be 0 and 1, respectively.
+    Subresource->baseArrayLayer = 0;
+    Subresource->layerCount     = 1;
+}
 }  // anonymous namespace
 
 // TextureVk implementation.
@@ -587,6 +595,12 @@ angle::Result TextureVk::copySubImageImplWithTransfer(ContextVk *contextVk,
     srcSubresource.baseArrayLayer           = static_cast<uint32_t>(sourceLayer);
     srcSubresource.layerCount               = layerCount;
 
+    if (srcImage->getExtents().depth > 1)
+    {
+        srcOffset.z = srcSubresource.baseArrayLayer;
+        Set3DBaseArrayLayerAndLayerCount(&srcSubresource);
+    }
+
     // If destination is valid, copy the source directly into it.
     if (mImage->valid())
     {
@@ -605,8 +619,7 @@ angle::Result TextureVk::copySubImageImplWithTransfer(ContextVk *contextVk,
         VkImageType imageType = gl_vk::GetImageType(mState.getType());
         if (imageType == VK_IMAGE_TYPE_3D)
         {
-            destSubresource.baseArrayLayer = 0;
-            destSubresource.layerCount     = 1;
+            Set3DBaseArrayLayerAndLayerCount(&destSubresource);
         }
 
         vk::ImageHelper::Copy(srcImage, mImage, srcOffset, destOffset, extents, srcSubresource,

src/tests/gl_tests/CopyTexImageTest.cpp

@@ -630,6 +630,43 @@ TEST_P(CopyTexImageTestES3, 2DArraySubImage)
     ASSERT_GL_NO_ERROR();
 }
 
+// Test if glCopyTexImage2D() implementation performs conversions well from GL_TEXTURE_3D to
+// GL_TEXTURE_2D.
+TEST_P(CopyTexImageTestES3, CopyTexSubImageFromTexture3D)
+{
+    // TODO(anglebug.com/3801)
+    // Seems to fail on D3D11 Windows.
+    ANGLE_SKIP_TEST_IF(IsD3D11() & IsWindows());
+
+    constexpr GLsizei kTexSize = 4;
+    constexpr GLsizei kLayers  = 2;
+    std::vector<GLColor> red(kTexSize * kTexSize * kLayers, GLColor::red);
+
+    GLFramebuffer fbo;
+    glBindFramebuffer(GL_READ_FRAMEBUFFER, fbo);
+    glBindTexture(GL_TEXTURE_2D, 0);
+
+    // We will be reading from zeroth color attachment.
+    glReadBuffer(GL_COLOR_ATTACHMENT0);
+
+    GLTexture src_object_id;
+    glBindTexture(GL_TEXTURE_3D, src_object_id);
+    glTexImage3D(GL_TEXTURE_3D, 0, GL_RGBA8, kTexSize, kTexSize, kLayers, 0, GL_RGBA,
+                 GL_UNSIGNED_BYTE, NULL);
+    glTexSubImage3D(GL_TEXTURE_3D, 0, 0, 0, 1, kTexSize, kTexSize, 1, GL_RGBA, GL_UNSIGNED_BYTE,
+                    red.data());
+    glFramebufferTextureLayer(GL_READ_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, src_object_id, 0, 1);
+    ASSERT_GL_NO_ERROR();
+
+    GLTexture dst_object_id;
+    glBindTexture(GL_TEXTURE_2D, dst_object_id);
+    glCopyTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, 0, 0, kTexSize, kTexSize, 0);
+    glFramebufferTexture2D(GL_READ_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, dst_object_id,
+                           0);
+    EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);
+    ASSERT_GL_NO_ERROR();
+}
+
 // Initialize the 3D texture we will copy the subImage data into
 void CopyTexImageTestES3::initialize3DTexture(GLTexture &texture,
                                               const GLsizei imageWidth,