Geometry Nodes: Random Value Node

This node replaces the deprecated Attribute Randomize node, populating
a vector, float, integer or boolean field with random values. Vector,
float, and integer have min/max settings, which are also field aware.
The boolean type has a probability value for controlling what portion
of the output should be true. All four types have a field seed input
which is implicitly driven by the index, otherwise, all values would
be the same "random" value.

The Random Float node is now deprecated like other nodes, since it is
redundant with this node.

Differential Revision: https://developer.blender.org/D12603

1 files changed, 86 insertions, 0 deletions

diff --git a/source/blender/nodes/function/nodes/legacy/node_fn_random_float.cc b/source/blender/nodes/function/nodes/legacy/node_fn_random_float.cc
new file mode 100644
index 00000000000..7f6f554ba93
--- /dev/null
+++ b/source/blender/nodes/function/nodes/legacy/node_fn_random_float.cc
@@ -0,0 +1,86 @@
+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ */
+
+#include "node_function_util.hh"
+
+#include "BLI_hash.h"
+
+namespace blender::nodes {
+
+static void fn_node_legacy_random_float_declare(NodeDeclarationBuilder &b)
+{
+  b.is_function_node();
+  b.add_input<decl::Float>("Min").min(-10000.0f).max(10000.0f);
+  b.add_input<decl::Float>("Max").default_value(1.0f).min(-10000.0f).max(10000.0f);
+  b.add_input<decl::Int>("Seed").min(-10000).max(10000);
+  b.add_output<decl::Float>("Value");
+};
+
+}  // namespace blender::nodes
+
+class RandomFloatFunction : public blender::fn::MultiFunction {
+ public:
+  RandomFloatFunction()
+  {
+    static blender::fn::MFSignature signature = create_signature();
+    this->set_signature(&signature);
+  }
+
+  static blender::fn::MFSignature create_signature()
+  {
+    blender::fn::MFSignatureBuilder signature{"Random float"};
+    signature.single_input<float>("Min");
+    signature.single_input<float>("Max");
+    signature.single_input<int>("Seed");
+    signature.single_output<float>("Value");
+    return signature.build();
+  }
+
+  void call(blender::IndexMask mask,
+            blender::fn::MFParams params,
+            blender::fn::MFContext UNUSED(context)) const override
+  {
+    const blender::VArray<float> &min_values = params.readonly_single_input<float>(0, "Min");
+    const blender::VArray<float> &max_values = params.readonly_single_input<float>(1, "Max");
+    const blender::VArray<int> &seeds = params.readonly_single_input<int>(2, "Seed");
+    blender::MutableSpan<float> values = params.uninitialized_single_output<float>(3, "Value");
+
+    for (int64_t i : mask) {
+      const float min_value = min_values[i];
+      const float max_value = max_values[i];
+      const int seed = seeds[i];
+      const float value = BLI_hash_int_01(static_cast<uint32_t>(seed));
+      values[i] = value * (max_value - min_value) + min_value;
+    }
+  }
+};
+
+static void fn_node_legacy_random_float_build_multi_function(
+    blender::nodes::NodeMultiFunctionBuilder &builder)
+{
+  static RandomFloatFunction fn;
+  builder.set_matching_fn(fn);
+}
+
+void register_node_type_fn_legacy_random_float()
+{
+  static bNodeType ntype;
+
+  fn_node_type_base(&ntype, FN_NODE_LEGACY_RANDOM_FLOAT, "Random Float", 0, 0);
+  ntype.declare = blender::nodes::fn_node_legacy_random_float_declare;
+  ntype.build_multi_function = fn_node_legacy_random_float_build_multi_function;
+  nodeRegisterType(&ntype);
+}