Add test asset support with STRIP_ALL guards

Fixes test_assets.cc compilation by adding missing test asset IDs and
procedural generators. Test-specific code is protected with DEMO_STRIP_ALL
to exclude from release builds.

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

1 files changed, 14 insertions, 0 deletions

diff --git a/src/procedural/generator.cc b/src/procedural/generator.cc
index 18ad133..7c165db 100644
--- a/src/procedural/generator.cc
+++ b/src/procedural/generator.cc
@@ -191,4 +191,18 @@ bool make_periodic(uint8_t* buffer, int w, int h, const float* params,
   return true;
 }
 
+#if !defined(DEMO_STRIP_ALL)
+// Test-only: 256x256 noise generator
+bool gen_noise_256(uint8_t* buffer, int w, int h, const float* params,
+                   int num_params) {
+  return gen_noise(buffer, w, h, params, num_params);
+}
+
+// Test-only: Failing generator
+bool gen_fail(uint8_t* buffer, int w, int h, const float* params,
+              int num_params) {
+  return false;
+}
+#endif
+
 } // namespace procedural