Add Chromium-only Blender WebEngine parity work

blender-5.2.0/intern/cycles/kernel/svm/checker.h

@@ -0,0 +1,46 @@
+/* SPDX-FileCopyrightText: 2011-2022 Blender Foundation
+ *
+ * SPDX-License-Identifier: Apache-2.0 */
+
+#pragma once
+
+#include "kernel/svm/node_types.h"
+#include "kernel/svm/util.h"
+
+CCL_NAMESPACE_BEGIN
+
+/* Checker */
+
+ccl_device float svm_checker(float3 p)
+{
+  /* avoid precision issues on unit coordinates */
+  p.x = (p.x + 0.000001f) * 0.999999f;
+  p.y = (p.y + 0.000001f) * 0.999999f;
+  p.z = (p.z + 0.000001f) * 0.999999f;
+
+  const int xi = abs(float_to_int(floorf(p.x)));
+  const int yi = abs(float_to_int(floorf(p.y)));
+  const int zi = abs(float_to_int(floorf(p.z)));
+
+  return ((xi % 2 == yi % 2) == (zi % 2)) ? 1.0f : 0.0f;
+}
+
+ccl_device_noinline void svm_node_tex_checker(
+    ccl_private float *ccl_restrict stack, const ccl_global SVMNodeTexChecker &ccl_restrict node)
+{
+  const float3 co = stack_load_float3(stack, node.co);
+  const float3 color1 = stack_load(stack, node.color1);
+  const float3 color2 = stack_load(stack, node.color2);
+  const float scale = stack_load(stack, node.scale);
+
+  const float f = svm_checker(co * scale);
+
+  if (stack_valid(node.color_offset)) {
+    stack_store_float3(stack, node.color_offset, (f == 1.0f) ? color1 : color2);
+  }
+  if (stack_valid(node.fac_offset)) {
+    stack_store_float(stack, node.fac_offset, f);
+  }
+}
+
+CCL_NAMESPACE_END