Nodes: Add Float Curve for GN and Shader nodes.

Replacement for float curve in legacy Attribute Curve Map node.

Float Curve defaults to [0.0-1.0] range.

Reviewed By: JacquesLucke, brecht

Differential Revision: https://developer.blender.org/D12683

2 files changed, 40 insertions, 5 deletions

diff --git a/intern/cycles/blender/blender_shader.cpp b/intern/cycles/blender/blender_shader.cpp
index 8c4f789ffd0..0b8aea15d6c 100644
--- a/intern/cycles/blender/blender_shader.cpp
+++ b/intern/cycles/blender/blender_shader.cpp
@@ -279,7 +279,7 @@ static ShaderNode *add_node(Scene *scene,
     array<float3> curve_mapping_curves;
     float min_x, max_x;
     curvemapping_color_to_array(mapping, curve_mapping_curves, RAMP_TABLE_SIZE, true);
-    curvemapping_minmax(mapping, true, &min_x, &max_x);
+    curvemapping_minmax(mapping, 4, &min_x, &max_x);
     curves->set_min_x(min_x);
     curves->set_max_x(max_x);
     curves->set_curves(curve_mapping_curves);
@@ -292,12 +292,25 @@ static ShaderNode *add_node(Scene *scene,
     array<float3> curve_mapping_curves;
     float min_x, max_x;
     curvemapping_color_to_array(mapping, curve_mapping_curves, RAMP_TABLE_SIZE, false);
-    curvemapping_minmax(mapping, false, &min_x, &max_x);
+    curvemapping_minmax(mapping, 3, &min_x, &max_x);
     curves->set_min_x(min_x);
     curves->set_max_x(max_x);
     curves->set_curves(curve_mapping_curves);
     node = curves;
   }
+  else if (b_node.is_a(&RNA_ShaderNodeFloatCurve)) {
+    BL::ShaderNodeFloatCurve b_curve_node(b_node);
+    BL::CurveMapping mapping(b_curve_node.mapping());
+    FloatCurveNode *curve = graph->create_node<FloatCurveNode>();
+    array<float> curve_mapping_curve;
+    float min_x, max_x;
+    curvemapping_float_to_array(mapping, curve_mapping_curve, RAMP_TABLE_SIZE);
+    curvemapping_minmax(mapping, 1, &min_x, &max_x);
+    curve->set_min_x(min_x);
+    curve->set_max_x(max_x);
+    curve->set_curve(curve_mapping_curve);
+    node = curve;
+  }
   else if (b_node.is_a(&RNA_ShaderNodeValToRGB)) {
     RGBRampNode *ramp = graph->create_node<RGBRampNode>();
     BL::ShaderNodeValToRGB b_ramp_node(b_node);
diff --git a/intern/cycles/blender/blender_util.h b/intern/cycles/blender/blender_util.h
index 128fcbd7055..77b2bd5ac4f 100644
--- a/intern/cycles/blender/blender_util.h
+++ b/intern/cycles/blender/blender_util.h
@@ -171,12 +171,11 @@ static inline void curvemap_minmax_curve(/*const*/ BL::CurveMap &curve, float *m
 }
 
 static inline void curvemapping_minmax(/*const*/ BL::CurveMapping &cumap,
-                                       bool rgb_curve,
+                                       int num_curves,
                                        float *min_x,
                                        float *max_x)
 {
   // const int num_curves = cumap.curves.length(); /* Gives linking error so far. */
-  const int num_curves = rgb_curve ? 4 : 3;
   *min_x = FLT_MAX;
   *max_x = -FLT_MAX;
   for (int i = 0; i < num_curves; ++i) {
@@ -196,6 +195,28 @@ static inline void curvemapping_to_array(BL::CurveMapping &cumap, array<float> &
   }
 }
 
+static inline void curvemapping_float_to_array(BL::CurveMapping &cumap,
+                                               array<float> &data,
+                                               int size)
+{
+  float min = 0.0f, max = 1.0f;
+
+  curvemapping_minmax(cumap, 1, &min, &max);
+
+  const float range = max - min;
+
+  cumap.update();
+
+  BL::CurveMap map = cumap.curves[0];
+
+  data.resize(size);
+
+  for (int i = 0; i < size; i++) {
+    float t = min + (float)i / (float)(size - 1) * range;
+    data[i] = cumap.evaluate(map, t);
+  }
+}
+
 static inline void curvemapping_color_to_array(BL::CurveMapping &cumap,
                                                array<float3> &data,
                                                int size,
@@ -214,7 +235,8 @@ static inline void curvemapping_color_to_array(BL::CurveMapping &cumap,
    *
    * There might be some better estimations here tho.
    */
-  curvemapping_minmax(cumap, rgb_curve, &min_x, &max_x);
+  const int num_curves = rgb_curve ? 4 : 3;
+  curvemapping_minmax(cumap, num_curves, &min_x, &max_x);
 
   const float range_x = max_x - min_x;