Nodes: Support storing socket link limits in bNodeSocketType

Currently the link limit of sockets is stored in bNodeSocket->limit.
This allows for a lot of flexibility, but is also very redundant.
In every case I've had to deal with so far, it would have "more correct"
to set the link limit per socket type and not per socket. I did not enforce
this constraint yet, because the link limit is exposed in the Python API,
which I did not want to break here.

In the future it might even make sense to only support only three kinds of link limits:
a) no links, b) at most one link, c) an arbitrary number links links. The other link
limits usually don't work well with tools (e.g. which link should be removed when a new
one is connected?) and is not used in practice. However, that is for another day.

Eventually, I would like to get rid of bNodeSocket->limit completely and replace it
either with fixed link limits or a callback in bNodeSocketType.

This patch consists of three parts:

**1. Support defining link limit in socket type**
This introduces a new `nodeSocketLinkLimit` function that serves as an indirection to
hide where the link limit of a socket is defined.

**2. Define link limits for builtin sockets on socket type**
Data sockets: one input, many outputs
Virtual sockets: one input, one output
Undefined sockets: many inputs, many outputs (to avoid that links are removed when the type of the socket is not known)

**3. Remove `bNodeSocketTemplate->limit`**
This wasn't used anymore after the second commit. Removing it simplifies socket definitions
in hundreds of places and removes a lot of redundancy.

Differential Revision: https://developer.blender.org/D7038

Reviewers: brecht

1 files changed, 37 insertions, 37 deletions

diff --git a/source/blender/nodes/texture/nodes/node_texture_proc.c b/source/blender/nodes/texture/nodes/node_texture_proc.c
index 5c3b0dc7f55..ac6a5e6e845 100644
--- a/source/blender/nodes/texture/nodes/node_texture_proc.c
+++ b/source/blender/nodes/texture/nodes/node_texture_proc.c
@@ -31,17 +31,17 @@
  */
 
 static bNodeSocketTemplate outputs_both[] = {
-    {SOCK_RGBA, 0, N_("Color"), 1.0f, 0.0f, 0.0f, 1.0f},
-    {SOCK_VECTOR, 0, N_("Normal"), 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f, PROP_DIRECTION},
-    {-1, 0, ""}};
-static bNodeSocketTemplate outputs_color_only[] = {{SOCK_RGBA, 0, N_("Color")}, {-1, 0, ""}};
+    {SOCK_RGBA, N_("Color"), 1.0f, 0.0f, 0.0f, 1.0f},
+    {SOCK_VECTOR, N_("Normal"), 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f, PROP_DIRECTION},
+    {-1, ""}};
+static bNodeSocketTemplate outputs_color_only[] = {{SOCK_RGBA, N_("Color")}, {-1, ""}};
 
 /* Inputs common to all, #defined because nodes will need their own inputs too */
 #define I 2 /* count */
 #define COMMON_INPUTS \
-  {SOCK_RGBA, 1, "Color 1", 0.0f, 0.0f, 0.0f, 1.0f}, \
+  {SOCK_RGBA, "Color 1", 0.0f, 0.0f, 0.0f, 1.0f}, \
   { \
-    SOCK_RGBA, 1, "Color 2", 1.0f, 1.0f, 1.0f, 1.0f \
+    SOCK_RGBA, "Color 2", 1.0f, 1.0f, 1.0f, 1.0f \
   }
 
 /* Calls multitex and copies the result to the outputs.
@@ -146,15 +146,15 @@ static int count_outputs(bNode *node)
 /* --- VORONOI -- */
 static bNodeSocketTemplate voronoi_inputs[] = {
     COMMON_INPUTS,
-    {SOCK_FLOAT, 1, N_("W1"), 1.0f, 0.0f, 0.0f, 0.0f, -2.0f, 2.0f, PROP_NONE},
-    {SOCK_FLOAT, 1, N_("W2"), 0.0f, 0.0f, 0.0f, 0.0f, -2.0f, 2.0f, PROP_NONE},
-    {SOCK_FLOAT, 1, N_("W3"), 0.0f, 0.0f, 0.0f, 0.0f, -2.0f, 2.0f, PROP_NONE},
-    {SOCK_FLOAT, 1, N_("W4"), 0.0f, 0.0f, 0.0f, 0.0f, -2.0f, 2.0f, PROP_NONE},
+    {SOCK_FLOAT, N_("W1"), 1.0f, 0.0f, 0.0f, 0.0f, -2.0f, 2.0f, PROP_NONE},
+    {SOCK_FLOAT, N_("W2"), 0.0f, 0.0f, 0.0f, 0.0f, -2.0f, 2.0f, PROP_NONE},
+    {SOCK_FLOAT, N_("W3"), 0.0f, 0.0f, 0.0f, 0.0f, -2.0f, 2.0f, PROP_NONE},
+    {SOCK_FLOAT, N_("W4"), 0.0f, 0.0f, 0.0f, 0.0f, -2.0f, 2.0f, PROP_NONE},
 
-    {SOCK_FLOAT, 1, N_("iScale"), 1.0f, 0.0f, 0.0f, 0.0f, 0.01f, 10.0f, PROP_UNSIGNED},
-    {SOCK_FLOAT, 1, N_("Size"), 0.25f, 0.0f, 0.0f, 0.0f, 0.0001f, 4.0f, PROP_UNSIGNED},
+    {SOCK_FLOAT, N_("iScale"), 1.0f, 0.0f, 0.0f, 0.0f, 0.01f, 10.0f, PROP_UNSIGNED},
+    {SOCK_FLOAT, N_("Size"), 0.25f, 0.0f, 0.0f, 0.0f, 0.0001f, 4.0f, PROP_UNSIGNED},
 
-    {-1, 0, ""}};
+    {-1, ""}};
 static void voronoi_map_inputs(Tex *tex, bNodeStack **in, TexParams *p, short thread)
 {
   tex->vn_w1 = tex_input_value(in[I + 0], p, thread);
@@ -168,15 +168,15 @@ static void voronoi_map_inputs(Tex *tex, bNodeStack **in, TexParams *p, short th
 ProcDef(voronoi);
 
 /* --- BLEND -- */
-static bNodeSocketTemplate blend_inputs[] = {COMMON_INPUTS, {-1, 0, ""}};
+static bNodeSocketTemplate blend_inputs[] = {COMMON_INPUTS, {-1, ""}};
 ProcNoInputs(blend);
 ProcDef(blend);
 
 /* -- MAGIC -- */
 static bNodeSocketTemplate magic_inputs[] = {
     COMMON_INPUTS,
-    {SOCK_FLOAT, 1, N_("Turbulence"), 5.0f, 0.0f, 0.0f, 0.0f, 0.0f, 200.0f, PROP_UNSIGNED},
-    {-1, 0, ""}};
+    {SOCK_FLOAT, N_("Turbulence"), 5.0f, 0.0f, 0.0f, 0.0f, 0.0f, 200.0f, PROP_UNSIGNED},
+    {-1, ""}};
 static void magic_map_inputs(Tex *tex, bNodeStack **in, TexParams *p, short thread)
 {
   tex->turbul = tex_input_value(in[I + 0], p, thread);
@@ -186,9 +186,9 @@ ProcDef(magic);
 /* --- MARBLE --- */
 static bNodeSocketTemplate marble_inputs[] = {
     COMMON_INPUTS,
-    {SOCK_FLOAT, 1, N_("Size"), 0.25f, 0.0f, 0.0f, 0.0f, 0.0001f, 2.0f, PROP_UNSIGNED},
-    {SOCK_FLOAT, 1, N_("Turbulence"), 5.0f, 0.0f, 0.0f, 0.0f, 0.0f, 200.0f, PROP_UNSIGNED},
-    {-1, 0, ""}};
+    {SOCK_FLOAT, N_("Size"), 0.25f, 0.0f, 0.0f, 0.0f, 0.0001f, 2.0f, PROP_UNSIGNED},
+    {SOCK_FLOAT, N_("Turbulence"), 5.0f, 0.0f, 0.0f, 0.0f, 0.0f, 200.0f, PROP_UNSIGNED},
+    {-1, ""}};
 static void marble_map_inputs(Tex *tex, bNodeStack **in, TexParams *p, short thread)
 {
   tex->noisesize = tex_input_value(in[I + 0], p, thread);
@@ -199,8 +199,8 @@ ProcDef(marble);
 /* --- CLOUDS --- */
 static bNodeSocketTemplate clouds_inputs[] = {
     COMMON_INPUTS,
-    {SOCK_FLOAT, 1, N_("Size"), 0.25f, 0.0f, 0.0f, 0.0f, 0.0001f, 2.0f, PROP_UNSIGNED},
-    {-1, 0, ""}};
+    {SOCK_FLOAT, N_("Size"), 0.25f, 0.0f, 0.0f, 0.0f, 0.0001f, 2.0f, PROP_UNSIGNED},
+    {-1, ""}};
 static void clouds_map_inputs(Tex *tex, bNodeStack **in, TexParams *p, short thread)
 {
   tex->noisesize = tex_input_value(in[I + 0], p, thread);
@@ -210,9 +210,9 @@ ProcDef(clouds);
 /* --- DISTORTED NOISE --- */
 static bNodeSocketTemplate distnoise_inputs[] = {
     COMMON_INPUTS,
-    {SOCK_FLOAT, 1, N_("Size"), 0.25f, 0.0f, 0.0f, 0.0f, 0.0001f, 2.0f, PROP_UNSIGNED},
-    {SOCK_FLOAT, 1, N_("Distortion"), 1.00f, 0.0f, 0.0f, 0.0f, 0.0000f, 10.0f, PROP_UNSIGNED},
-    {-1, 0, ""}};
+    {SOCK_FLOAT, N_("Size"), 0.25f, 0.0f, 0.0f, 0.0f, 0.0001f, 2.0f, PROP_UNSIGNED},
+    {SOCK_FLOAT, N_("Distortion"), 1.00f, 0.0f, 0.0f, 0.0f, 0.0000f, 10.0f, PROP_UNSIGNED},
+    {-1, ""}};
 static void distnoise_map_inputs(Tex *tex, bNodeStack **in, TexParams *p, short thread)
 {
   tex->noisesize = tex_input_value(in[I + 0], p, thread);
@@ -223,9 +223,9 @@ ProcDef(distnoise);
 /* --- WOOD --- */
 static bNodeSocketTemplate wood_inputs[] = {
     COMMON_INPUTS,
-    {SOCK_FLOAT, 1, N_("Size"), 0.25f, 0.0f, 0.0f, 0.0f, 0.0001f, 2.0f, PROP_UNSIGNED},
-    {SOCK_FLOAT, 1, N_("Turbulence"), 5.0f, 0.0f, 0.0f, 0.0f, 0.0f, 200.0f, PROP_UNSIGNED},
-    {-1, 0, ""}};
+    {SOCK_FLOAT, N_("Size"), 0.25f, 0.0f, 0.0f, 0.0f, 0.0001f, 2.0f, PROP_UNSIGNED},
+    {SOCK_FLOAT, N_("Turbulence"), 5.0f, 0.0f, 0.0f, 0.0f, 0.0f, 200.0f, PROP_UNSIGNED},
+    {-1, ""}};
 static void wood_map_inputs(Tex *tex, bNodeStack **in, TexParams *p, short thread)
 {
   tex->noisesize = tex_input_value(in[I + 0], p, thread);
@@ -236,13 +236,13 @@ ProcDef(wood);
 /* --- MUSGRAVE --- */
 static bNodeSocketTemplate musgrave_inputs[] = {
     COMMON_INPUTS,
-    {SOCK_FLOAT, 1, N_("H"), 1.0f, 0.0f, 0.0f, 0.0f, 0.0001f, 2.0f, PROP_UNSIGNED},
-    {SOCK_FLOAT, 1, N_("Lacunarity"), 2.0f, 0.0f, 0.0f, 0.0f, 0.0f, 6.0f, PROP_UNSIGNED},
-    {SOCK_FLOAT, 1, N_("Octaves"), 2.0f, 0.0f, 0.0f, 0.0f, 0.0f, 8.0f, PROP_UNSIGNED},
+    {SOCK_FLOAT, N_("H"), 1.0f, 0.0f, 0.0f, 0.0f, 0.0001f, 2.0f, PROP_UNSIGNED},
+    {SOCK_FLOAT, N_("Lacunarity"), 2.0f, 0.0f, 0.0f, 0.0f, 0.0f, 6.0f, PROP_UNSIGNED},
+    {SOCK_FLOAT, N_("Octaves"), 2.0f, 0.0f, 0.0f, 0.0f, 0.0f, 8.0f, PROP_UNSIGNED},
 
-    {SOCK_FLOAT, 1, N_("iScale"), 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 10.0f, PROP_UNSIGNED},
-    {SOCK_FLOAT, 1, N_("Size"), 0.25f, 0.0f, 0.0f, 0.0f, 0.0001f, 2.0f, PROP_UNSIGNED},
-    {-1, 0, ""}};
+    {SOCK_FLOAT, N_("iScale"), 1.0f, 0.0f, 0.0f, 0.0f, 0.0f, 10.0f, PROP_UNSIGNED},
+    {SOCK_FLOAT, N_("Size"), 0.25f, 0.0f, 0.0f, 0.0f, 0.0001f, 2.0f, PROP_UNSIGNED},
+    {-1, ""}};
 static void musgrave_map_inputs(Tex *tex, bNodeStack **in, TexParams *p, short thread)
 {
   tex->mg_H = tex_input_value(in[I + 0], p, thread);
@@ -254,16 +254,16 @@ static void musgrave_map_inputs(Tex *tex, bNodeStack **in, TexParams *p, short t
 ProcDef(musgrave);
 
 /* --- NOISE --- */
-static bNodeSocketTemplate noise_inputs[] = {COMMON_INPUTS, {-1, 0, ""}};
+static bNodeSocketTemplate noise_inputs[] = {COMMON_INPUTS, {-1, ""}};
 ProcNoInputs(noise);
 ProcDef(noise);
 
 /* --- STUCCI --- */
 static bNodeSocketTemplate stucci_inputs[] = {
     COMMON_INPUTS,
-    {SOCK_FLOAT, 1, N_("Size"), 0.25f, 0.0f, 0.0f, 0.0f, 0.0001f, 2.0f, PROP_UNSIGNED},
-    {SOCK_FLOAT, 1, N_("Turbulence"), 5.0f, 0.0f, 0.0f, 0.0f, 0.0f, 200.0f, PROP_UNSIGNED},
-    {-1, 0, ""}};
+    {SOCK_FLOAT, N_("Size"), 0.25f, 0.0f, 0.0f, 0.0f, 0.0001f, 2.0f, PROP_UNSIGNED},
+    {SOCK_FLOAT, N_("Turbulence"), 5.0f, 0.0f, 0.0f, 0.0f, 0.0f, 200.0f, PROP_UNSIGNED},
+    {-1, ""}};
 static void stucci_map_inputs(Tex *tex, bNodeStack **in, TexParams *p, short thread)
 {
   tex->noisesize = tex_input_value(in[I + 0], p, thread);