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

3 files changed, 37 insertions, 7 deletions

diff --git a/source/blender/nodes/NOD_static_types.h b/source/blender/nodes/NOD_static_types.h
index f3bc5a0cafa..a8163391c13 100644
--- a/source/blender/nodes/NOD_static_types.h
+++ b/source/blender/nodes/NOD_static_types.h
@@ -51,7 +51,7 @@ DefNode(ShaderNode,     SH_NODE_CURVE_VEC,       def_vector_curve,       "CURVE_
 DefNode(ShaderNode,     SH_NODE_CURVE_RGB,       def_rgb_curve,          "CURVE_RGB",      RGBCurve,         "RGB Curves",        ""              )
 DefNode(ShaderNode,     SH_NODE_CAMERA,          0,                      "CAMERA",         CameraData,       "Camera Data",       ""              )
 DefNode(ShaderNode,     SH_NODE_MAP_RANGE,       def_map_range,          "MAP_RANGE",      MapRange,         "Map Range",         ""              )
-DefNode(ShaderNode,     SH_NODE_CLAMP,           0,                      "CLAMP",          Clamp,            "Clamp",             ""              )
+DefNode(ShaderNode,     SH_NODE_CLAMP,           def_clamp,              "CLAMP",          Clamp,            "Clamp",             ""              )
 DefNode(ShaderNode,     SH_NODE_MATH,            def_math,               "MATH",           Math,             "Math",              ""              )
 DefNode(ShaderNode,     SH_NODE_VECTOR_MATH,     def_vector_math,        "VECT_MATH",      VectorMath,       "Vector Math",       ""              )
 DefNode(ShaderNode,     SH_NODE_SQUEEZE,         0,                      "SQUEEZE",        Squeeze,          "Squeeze Value",     ""              )
diff --git a/source/blender/nodes/shader/nodes/node_shader_clamp.c b/source/blender/nodes/shader/nodes/node_shader_clamp.c
index 8e5b90436ea..329d7492db6 100644
--- a/source/blender/nodes/shader/nodes/node_shader_clamp.c
+++ b/source/blender/nodes/shader/nodes/node_shader_clamp.c
@@ -35,13 +35,19 @@ static bNodeSocketTemplate sh_node_clamp_out[] = {
     {-1, 0, ""},
 };
 
+static void node_shader_init_clamp(bNodeTree *UNUSED(ntree), bNode *node)
+{
+  node->custom1 = NODE_CLAMP_MINMAX; /* clamp type */
+}
+
 static int gpu_shader_clamp(GPUMaterial *mat,
                             bNode *node,
                             bNodeExecData *UNUSED(execdata),
                             GPUNodeStack *in,
                             GPUNodeStack *out)
 {
-  return GPU_stack_link(mat, node, "clamp_value", in, out);
+  return (node->custom1 == NODE_CLAMP_MINMAX) ? GPU_stack_link(mat, node, "clamp_value", in, out) :
+                                                GPU_stack_link(mat, node, "clamp_range", in, out);
 }
 
 void register_node_type_sh_clamp(void)
@@ -50,6 +56,7 @@ void register_node_type_sh_clamp(void)
 
   sh_node_type_base(&ntype, SH_NODE_CLAMP, "Clamp", NODE_CLASS_CONVERTOR, 0);
   node_type_socket_templates(&ntype, sh_node_clamp_in, sh_node_clamp_out);
+  node_type_init(&ntype, node_shader_init_clamp);
   node_type_gpu(&ntype, gpu_shader_clamp);
 
   nodeRegisterType(&ntype);
diff --git a/source/blender/nodes/shader/nodes/node_shader_map_range.c b/source/blender/nodes/shader/nodes/node_shader_map_range.c
index 7ebf3faf1f3..c410dc7a981 100644
--- a/source/blender/nodes/shader/nodes/node_shader_map_range.c
+++ b/source/blender/nodes/shader/nodes/node_shader_map_range.c
@@ -30,6 +30,7 @@ static bNodeSocketTemplate sh_node_map_range_in[] = {
     {SOCK_FLOAT, 1, N_("From Max"), 1.0f, 1.0f, 1.0f, 1.0f, -10000.0f, 10000.0f, PROP_NONE},
     {SOCK_FLOAT, 1, N_("To Min"), 0.0f, 1.0f, 1.0f, 1.0f, -10000.0f, 10000.0f, PROP_NONE},
     {SOCK_FLOAT, 1, N_("To Max"), 1.0f, 1.0f, 1.0f, 1.0f, -10000.0f, 10000.0f, PROP_NONE},
+    {SOCK_FLOAT, 1, N_("Steps"), 4.0f, 1.0f, 1.0f, 1.0f, 0.0f, 10000.0f, PROP_NONE},
     {-1, 0, ""},
 };
 static bNodeSocketTemplate sh_node_map_range_out[] = {
@@ -37,9 +38,16 @@ static bNodeSocketTemplate sh_node_map_range_out[] = {
     {-1, 0, ""},
 };
 
+static void node_shader_update_map_range(bNodeTree *UNUSED(ntree), bNode *node)
+{
+  bNodeSocket *sockSteps = nodeFindSocket(node, SOCK_IN, "Steps");
+  nodeSetSocketAvailability(sockSteps, node->custom2 == NODE_MAP_RANGE_STEPPED);
+}
+
 static void node_shader_init_map_range(bNodeTree *UNUSED(ntree), bNode *node)
 {
-  node->custom1 = true;
+  node->custom1 = true;                  /* use_clamp */
+  node->custom2 = NODE_MAP_RANGE_LINEAR; /* interpolation */
 }
 
 static int gpu_shader_map_range(GPUMaterial *mat,
@@ -48,11 +56,25 @@ static int gpu_shader_map_range(GPUMaterial *mat,
                                 GPUNodeStack *in,
                                 GPUNodeStack *out)
 {
-  GPU_stack_link(mat, node, "map_range", in, out);
-  if (node->custom1) {
-    GPU_link(mat, "clamp_value", out[0].link, in[3].link, in[4].link, &out[0].link);
+  static const char *names[] = {
+      [NODE_MAP_RANGE_LINEAR] = "map_range_linear",
+      [NODE_MAP_RANGE_STEPPED] = "map_range_stepped",
+      [NODE_MAP_RANGE_SMOOTHSTEP] = "map_range_smoothstep",
+      [NODE_MAP_RANGE_SMOOTHERSTEP] = "map_range_smootherstep",
+  };
+
+  int ret = 0;
+  if (node->custom2 < ARRAY_SIZE(names) && names[node->custom2]) {
+    ret = GPU_stack_link(mat, node, names[node->custom2], in, out);
+  }
+  else {
+    ret = GPU_stack_link(mat, node, "map_range_linear", in, out);
+  }
+  if (ret && node->custom1 &&
+      !ELEM(node->custom2, NODE_MAP_RANGE_SMOOTHSTEP, NODE_MAP_RANGE_SMOOTHERSTEP)) {
+    GPU_link(mat, "clamp_range", out[0].link, in[3].link, in[4].link, &out[0].link);
   }
-  return 1;
+  return ret;
 }
 
 void register_node_type_sh_map_range(void)
@@ -62,6 +84,7 @@ void register_node_type_sh_map_range(void)
   sh_node_type_base(&ntype, SH_NODE_MAP_RANGE, "Map Range", NODE_CLASS_CONVERTOR, 0);
   node_type_socket_templates(&ntype, sh_node_map_range_in, sh_node_map_range_out);
   node_type_init(&ntype, node_shader_init_map_range);
+  node_type_update(&ntype, node_shader_update_map_range);
   node_type_gpu(&ntype, gpu_shader_map_range);
 
   nodeRegisterType(&ntype);