Shader Nodes: Add Interpolation modes to Map Range node

Modes: Linear interpolation (default), stepped linear, smoothstep and smootherstep.

This also includes an additional option for the **Clamp node** to switch between **Min Max** (default) and **Range** mode.

This was needed to allow clamping when **To Max** is less than **To Min**.

Reviewed By: JacquesLucke, brecht

Differential Revision: https://developer.blender.org/D5827

1 files changed, 28 insertions, 17 deletions

diff --git a/intern/cycles/render/nodes.cpp b/intern/cycles/render/nodes.cpp
index c6f1e8409eb..26f16d5ee80 100644
--- a/intern/cycles/render/nodes.cpp
+++ b/intern/cycles/render/nodes.cpp
@@ -5561,11 +5561,19 @@ NODE_DEFINE(MapRangeNode)
 {
   NodeType *type = NodeType::add("map_range", create, NodeType::SHADER);
 
+  static NodeEnum type_enum;
+  type_enum.insert("linear", NODE_MAP_RANGE_LINEAR);
+  type_enum.insert("stepped", NODE_MAP_RANGE_STEPPED);
+  type_enum.insert("smoothstep", NODE_MAP_RANGE_SMOOTHSTEP);
+  type_enum.insert("smootherstep", NODE_MAP_RANGE_SMOOTHERSTEP);
+  SOCKET_ENUM(type, "Type", type_enum, NODE_MAP_RANGE_LINEAR);
+
   SOCKET_IN_FLOAT(value, "Value", 1.0f);
   SOCKET_IN_FLOAT(from_min, "From Min", 0.0f);
   SOCKET_IN_FLOAT(from_max, "From Max", 1.0f);
   SOCKET_IN_FLOAT(to_min, "To Min", 0.0f);
   SOCKET_IN_FLOAT(to_max, "To Max", 1.0f);
+  SOCKET_IN_FLOAT(steps, "Steps", 4.0f);
 
   SOCKET_OUT_FLOAT(result, "Result");
 
@@ -5582,6 +5590,7 @@ void MapRangeNode::expand(ShaderGraph *graph)
     ShaderOutput *result_out = output("Result");
     if (!result_out->links.empty()) {
       ClampNode *clamp_node = new ClampNode();
+      clamp_node->type = NODE_CLAMP_RANGE;
       graph->add(clamp_node);
       graph->relink(result_out, clamp_node->output("Result"));
       graph->connect(result_out, clamp_node->input("Value"));
@@ -5601,20 +5610,6 @@ void MapRangeNode::expand(ShaderGraph *graph)
   }
 }
 
-void MapRangeNode::constant_fold(const ConstantFolder &folder)
-{
-  if (folder.all_inputs_constant()) {
-    float result;
-    if (from_max != from_min) {
-      result = to_min + ((value - from_min) / (from_max - from_min)) * (to_max - to_min);
-    }
-    else {
-      result = 0.0f;
-    }
-    folder.make_constant(result);
-  }
-}
-
 void MapRangeNode::compile(SVMCompiler &compiler)
 {
   ShaderInput *value_in = input("Value");
@@ -5622,6 +5617,7 @@ void MapRangeNode::compile(SVMCompiler &compiler)
   ShaderInput *from_max_in = input("From Max");
   ShaderInput *to_min_in = input("To Min");
   ShaderInput *to_max_in = input("To Max");
+  ShaderInput *steps_in = input("Steps");
   ShaderOutput *result_out = output("Result");
 
   int value_stack_offset = compiler.stack_assign(value_in);
@@ -5629,6 +5625,7 @@ void MapRangeNode::compile(SVMCompiler &compiler)
   int from_max_stack_offset = compiler.stack_assign_if_linked(from_max_in);
   int to_min_stack_offset = compiler.stack_assign_if_linked(to_min_in);
   int to_max_stack_offset = compiler.stack_assign_if_linked(to_max_in);
+  int steps_stack_offset = compiler.stack_assign(steps_in);
   int result_stack_offset = compiler.stack_assign(result_out);
 
   compiler.add_node(
@@ -5636,16 +5633,18 @@ void MapRangeNode::compile(SVMCompiler &compiler)
       value_stack_offset,
       compiler.encode_uchar4(
           from_min_stack_offset, from_max_stack_offset, to_min_stack_offset, to_max_stack_offset),
-      result_stack_offset);
+      compiler.encode_uchar4(type, steps_stack_offset, result_stack_offset));
 
   compiler.add_node(__float_as_int(from_min),
                     __float_as_int(from_max),
                     __float_as_int(to_min),
                     __float_as_int(to_max));
+  compiler.add_node(__float_as_int(steps));
 }
 
 void MapRangeNode::compile(OSLCompiler &compiler)
 {
+  compiler.parameter(this, "type");
   compiler.add(this, "node_map_range");
 }
 
@@ -5655,6 +5654,11 @@ NODE_DEFINE(ClampNode)
 {
   NodeType *type = NodeType::add("clamp", create, NodeType::SHADER);
 
+  static NodeEnum type_enum;
+  type_enum.insert("minmax", NODE_CLAMP_MINMAX);
+  type_enum.insert("range", NODE_CLAMP_RANGE);
+  SOCKET_ENUM(type, "Type", type_enum, NODE_CLAMP_MINMAX);
+
   SOCKET_IN_FLOAT(value, "Value", 1.0f);
   SOCKET_IN_FLOAT(min, "Min", 0.0f);
   SOCKET_IN_FLOAT(max, "Max", 1.0f);
@@ -5671,7 +5675,12 @@ ClampNode::ClampNode() : ShaderNode(node_type)
 void ClampNode::constant_fold(const ConstantFolder &folder)
 {
   if (folder.all_inputs_constant()) {
-    folder.make_constant(clamp(value, min, max));
+    if (type == NODE_CLAMP_RANGE && (min > max)) {
+      folder.make_constant(clamp(value, max, min));
+    }
+    else {
+      folder.make_constant(clamp(value, min, max));
+    }
   }
 }
 
@@ -5689,13 +5698,14 @@ void ClampNode::compile(SVMCompiler &compiler)
 
   compiler.add_node(NODE_CLAMP,
                     value_stack_offset,
-                    compiler.encode_uchar4(min_stack_offset, max_stack_offset),
+                    compiler.encode_uchar4(min_stack_offset, max_stack_offset, type),
                     result_stack_offset);
   compiler.add_node(__float_as_int(min), __float_as_int(max));
 }
 
 void ClampNode::compile(OSLCompiler &compiler)
 {
+  compiler.parameter(this, "type");
   compiler.add(this, "node_clamp");
 }
 
@@ -5769,6 +5779,7 @@ void MathNode::expand(ShaderGraph *graph)
     ShaderOutput *result_out = output("Value");
     if (!result_out->links.empty()) {
       ClampNode *clamp_node = new ClampNode();
+      clamp_node->type = NODE_CLAMP_MINMAX;
       clamp_node->min = 0.0f;
       clamp_node->max = 1.0f;
       graph->add(clamp_node);