1 files changed, 87 insertions, 0 deletions
diff --git a/intern/cycles/kernel/svm/ramp_util.h b/intern/cycles/kernel/svm/ramp_util.h
new file mode 100644
index 00000000000..f5951f7e283
--- /dev/null
+++ b/intern/cycles/kernel/svm/ramp_util.h
@@ -0,0 +1,87 @@
+/*
+ * Copyright 2011-2013 Blender Foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+CCL_NAMESPACE_BEGIN
+
+/* NOTE: svm_ramp.h, svm_ramp_util.h and node_ramp_util.h must stay consistent */
+
+ccl_device_inline float3
+rgb_ramp_lookup(const float3 *ramp, float f, bool interpolate, bool extrapolate, int table_size)
+{
+  if ((f < 0.0f || f > 1.0f) && extrapolate) {
+    float3 t0, dy;
+    if (f < 0.0f) {
+      t0 = ramp[0];
+      dy = t0 - ramp[1], f = -f;
+    }
+    else {
+      t0 = ramp[table_size - 1];
+      dy = t0 - ramp[table_size - 2];
+      f = f - 1.0f;
+    }
+    return t0 + dy * f * (table_size - 1);
+  }
+
+  f = clamp(f, 0.0f, 1.0f) * (table_size - 1);
+
+  /* clamp int as well in case of NaN */
+  int i = clamp(float_to_int(f), 0, table_size - 1);
+  float t = f - (float)i;
+
+  float3 result = ramp[i];
+
+  if (interpolate && t > 0.0f) {
+    result = (1.0f - t) * result + t * ramp[i + 1];
+  }
+
+  return result;
+}
+
+ccl_device float float_ramp_lookup(
+    const float *ramp, float f, bool interpolate, bool extrapolate, int table_size)
+{
+  if ((f < 0.0f || f > 1.0f) && extrapolate) {
+    float t0, dy;
+    if (f < 0.0f) {
+      t0 = ramp[0];
+      dy = t0 - ramp[1], f = -f;
+    }
+    else {
+      t0 = ramp[table_size - 1];
+      dy = t0 - ramp[table_size - 2];
+      f = f - 1.0f;
+    }
+    return t0 + dy * f * (table_size - 1);
+  }
+
+  f = clamp(f, 0.0f, 1.0f) * (table_size - 1);
+
+  /* clamp int as well in case of NaN */
+  int i = clamp(float_to_int(f), 0, table_size - 1);
+  float t = f - (float)i;
+
+  float result = ramp[i];
+
+  if (interpolate && t > 0.0f) {
+    result = (1.0f - t) * result + t * ramp[i + 1];
+  }
+
+  return result;
+}
+
+CCL_NAMESPACE_END