diff --git a/src/Vulkan/VkBufferView.cpp b/src/Vulkan/VkBufferView.cpp
index a8b49a0..3e048f1 100644
--- a/src/Vulkan/VkBufferView.cpp
+++ b/src/Vulkan/VkBufferView.cpp
@@ -19,7 +19,8 @@
 namespace vk {
 
 BufferView::BufferView(const VkBufferViewCreateInfo *pCreateInfo, void *mem)
-    : buffer(vk::Cast(pCreateInfo->buffer))
+    : id(pCreateInfo->format)
+    , buffer(vk::Cast(pCreateInfo->buffer))
     , format(pCreateInfo->format)
     , offset(pCreateInfo->offset)
 {
@@ -38,4 +39,4 @@
 	return buffer->getOffsetPointer(offset);
 }
 
-}  // namespace vk
\ No newline at end of file
+}  // namespace vk
diff --git a/src/Vulkan/VkBufferView.hpp b/src/Vulkan/VkBufferView.hpp
index 98b68cc..aa13fb5 100644
--- a/src/Vulkan/VkBufferView.hpp
+++ b/src/Vulkan/VkBufferView.hpp
@@ -38,7 +38,8 @@
 	uint32_t getRangeInBytes() const { return static_cast<uint32_t>(range); }
 	VkFormat getFormat() const { return format; }
 
-	const uint32_t id = ImageView::nextID++;  // ID space for sampling function cache, shared with imageviews
+	const Identifier id;
+
 private:
 	Buffer *buffer;
 	VkFormat format;
diff --git a/src/Vulkan/VkImageView.cpp b/src/Vulkan/VkImageView.cpp
index fc0c8bd..d9fbaf6 100644
--- a/src/Vulkan/VkImageView.cpp
+++ b/src/Vulkan/VkImageView.cpp
@@ -14,7 +14,9 @@
 
 #include "VkImageView.hpp"
 #include "VkImage.hpp"
-#include <System/Math.hpp>
+#include "System/Math.hpp"
+
+#include <climits>
 
 namespace {
 
@@ -54,7 +56,28 @@
 
 namespace vk {
 
-std::atomic<uint32_t> ImageView::nextID(1);
+Identifier::Identifier(const Image *image, VkImageViewType type, VkFormat fmt, VkComponentMapping mapping)
+{
+	imageViewType = type;
+	format = Format::mapTo8bit(fmt);
+	r = mapping.r;
+	g = mapping.g;
+	b = mapping.b;
+	a = mapping.a;
+
+	// TODO(b/152224843): eliminate
+	auto extent = image->getMipLevelExtent(VK_IMAGE_ASPECT_COLOR_BIT, 0);
+	large = (extent.width > SHRT_MAX) ||
+	        (extent.height > SHRT_MAX) ||
+	        (extent.depth > SHRT_MAX);
+}
+
+Identifier::Identifier(VkFormat fmt)
+{
+	static_assert(VK_IMAGE_VIEW_TYPE_END_RANGE == 6, "VkImageViewType does not allow using 7 to indicate buffer view");
+	imageViewType = 7;  // Still fits in 3-bit field
+	format = Format::mapTo8bit(fmt);
+}
 
 ImageView::ImageView(const VkImageViewCreateInfo *pCreateInfo, void *mem, const vk::SamplerYcbcrConversion *ycbcrConversion)
     : image(vk::Cast(pCreateInfo->image))
@@ -63,6 +86,7 @@
     , components(ResolveComponentMapping(pCreateInfo->components, format))
     , subresourceRange(ResolveRemainingLevelsLayers(pCreateInfo->subresourceRange, image))
     , ycbcrConversion(ycbcrConversion)
+    , id(image, viewType, format, components)
 {
 }
 
diff --git a/src/Vulkan/VkImageView.hpp b/src/Vulkan/VkImageView.hpp
index 65dca48..08ed4af 100644
--- a/src/Vulkan/VkImageView.hpp
+++ b/src/Vulkan/VkImageView.hpp
@@ -27,6 +27,36 @@
 
 class SamplerYcbcrConversion;
 
+// Uniquely identifies state used by sampling routine generation.
+// ID space shared by image views and buffer views.
+union Identifier
+{
+	// Image view identifier
+	Identifier(const Image *image, VkImageViewType type, VkFormat format, VkComponentMapping mapping);
+
+	// Buffer view identifier
+	Identifier(VkFormat format);
+
+	operator uint32_t() const
+	{
+		static_assert(sizeof(Identifier) == sizeof(uint32_t), "Identifier must be 32-bit");
+		return id;
+	}
+
+	uint32_t id = 0;
+
+	struct
+	{
+		uint32_t imageViewType : 3;
+		uint32_t format : 8;
+		uint32_t r : 3;
+		uint32_t g : 3;
+		uint32_t b : 3;
+		uint32_t a : 3;
+		uint32_t large : 1;  // Has dimension larger than SHRT_MAX (see b/133429305).
+	};
+};
+
 class ImageView : public Object<ImageView, VkImageView>
 {
 public:
@@ -82,22 +112,20 @@
 	const VkImageSubresourceRange &getSubresourceRange() const { return subresourceRange; }
 	size_t getImageSizeInBytes() const { return image->getMemoryRequirements().size; }
 
-	const uint32_t id = nextID++;
-
 private:
-	static std::atomic<uint32_t> nextID;
-	friend class BufferView;  // ImageView/BufferView share the ID space above.
-
 	bool imageTypesMatch(VkImageType imageType) const;
 	const Image *getImage(Usage usage) const;
 
 	Image *const image = nullptr;
 	const VkImageViewType viewType = VK_IMAGE_VIEW_TYPE_2D;
-	const Format format;
+	const Format format = VK_FORMAT_UNDEFINED;
 	const VkComponentMapping components = {};
 	const VkImageSubresourceRange subresourceRange = {};
 
 	const vk::SamplerYcbcrConversion *ycbcrConversion = nullptr;
+
+public:
+	const Identifier id;
 };
 
 // TODO(b/132437008): Also used by SamplerYcbcrConversion. Move somewhere centrally?