diff --git a/test/src/test_perlin.h b/test/src/test_perlin.h
index 3c9f2dc..0a86ca5 100644
--- a/test/src/test_perlin.h
+++ b/test/src/test_perlin.h
@@ -8,9 +8,36 @@
 #include "test_common.h"
 
 TEST_IMPL(GLM_PREFIX, perlin) {
-  vec4  p = {1.0f, 2.0f, 3.0f, 4.0f};
+  vec4 p1[] = {
+    {0.1f, 0.2f, 0.3f, 0.4f},
+    {0.2f, 0.3f, 0.4f, 0.5f},
+    {0.3f, 0.4f, 0.5f, 0.6f},
+    {0.4f, 0.5f, 0.6f, 0.7f},
+    {0.5f, 0.6f, 0.7f, 0.8f},
+    {0.6f, 0.7f, 0.8f, 0.9f},
+    {0.7f, 0.8f, 0.9f, 1.0f},
+    {0.8f, 0.9f, 1.0f, 1.1f},
+    {0.9f, 1.0f, 1.1f, 1.2f},
+    {1.0f, 1.1f, 1.2f, 1.3f},
+  };
+
+  // expected values calculated by glm::perlin
+  float e[] = {
+    -0.5091819763183594f,
+    -0.4375732541084290f,
+    -0.3212279379367828f,
+    -0.2279999703168869f,
+    -0.1577337533235550f,
+    -0.0445968918502331f,
+    0.1069696992635727f,
+    0.2067739963531494f,
+    0.2106968611478806f,
+    0.1397782564163208f
+  };
   
-  float out = GLM(perlin)(p);
-  ASSERT(test_eq(out, 10.0f))
+  for (int i = 0; i < 10; i++) {
+    ASSERT(test_eq(GLM(perlin)(p1[i]), e[i]));
+  }
+
   TEST_SUCCESS
 }