refactor(gpu): move SamplerCache impl to .cc, expose single entry point

get_or_create() and clear() moved out of the header-only class.
SamplerSpec and presets remain inline (trivial, no deps).

handoff(Gemini): sampler_cache split into .h/.cc, sampler_cache.cc added to COMMON_GPU_EFFECTS.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

1 files changed, 32 insertions, 0 deletions

diff --git a/src/gpu/sampler_cache.cc b/src/gpu/sampler_cache.cc
new file mode 100644
index 0000000..c61c232
--- /dev/null
+++ b/src/gpu/sampler_cache.cc
@@ -0,0 +1,32 @@
+// Sampler cache implementation
+// See sampler_cache.h
+#include "gpu/sampler_cache.h"
+
+#include "platform/platform.h"
+#include "util/fatal_error.h"
+
+WGPUSampler SamplerCache::get_or_create(WGPUDevice device,
+                                        const SamplerSpec& spec) {
+  HEADLESS_RETURN_VAL_IF_NULL(device, nullptr);
+
+  auto it = cache_.find(spec);
+  if (it != cache_.end())
+    return it->second;
+
+  WGPUSamplerDescriptor desc{};
+  desc.addressModeU = spec.u;
+  desc.addressModeV = spec.v;
+  desc.magFilter = spec.mag;
+  desc.minFilter = spec.min;
+  desc.maxAnisotropy = spec.anisotropy;
+  WGPUSampler sampler = wgpuDeviceCreateSampler(device, &desc);
+  cache_[spec] = sampler;
+  return sampler;
+}
+
+void SamplerCache::clear() {
+  for (auto& pair : cache_) {
+    wgpuSamplerRelease(pair.second);
+  }
+  cache_.clear();
+}