UI: Draw real node sockets for node input buttons

For buttons representing node inputs (e.g. in the material properties)
rather than drawing some generic socket icon, the actual sockets are
drawn now. That includes color, shape and the selection outline.

This should make it easier to understand what these buttons relate to.

Screenshots: {F8469252}, {F8469248} (The left alignment will be done in
a follow-up commit.)

Differential Revision: https://developer.blender.org/D7409

Reviewed by: Brecht Van Lommel, Clément Foucault, William Reynish

1 files changed, 166 insertions, 74 deletions

diff --git a/source/blender/editors/space_node/node_draw.c b/source/blender/editors/space_node/node_draw.c
index bdb7f787be6..bd8950c5085 100644
--- a/source/blender/editors/space_node/node_draw.c
+++ b/source/blender/editors/space_node/node_draw.c
@@ -707,39 +707,19 @@ static void node_draw_mute_line(View2D *v2d, SpaceNode *snode, bNode *node)
 #define MARKER_SHAPE_CIRCLE 0x2
 #define MARKER_SHAPE_INNER_DOT 0x10
 
-static void node_socket_draw(const bContext *C,
-                             bNodeTree *ntree,
-                             PointerRNA node_ptr,
-                             bNodeSocket *sock,
+static void node_socket_draw(const bNodeSocket *sock,
+                             const float color[4],
+                             const float color_outline[4],
+                             float size,
+                             int locx,
+                             int locy,
                              uint pos_id,
                              uint col_id,
                              uint shape_id,
                              uint size_id,
-                             uint outline_col_id,
-                             float size,
-                             bool selected)
+                             uint outline_col_id)
 {
-  PointerRNA ptr;
-  float color[4];
-  float outline_color[4];
-  uint flags = 0;
-
-  RNA_pointer_create((ID *)ntree, &RNA_NodeSocket, sock, &ptr);
-  sock->typeinfo->draw_color((bContext *)C, &ptr, &node_ptr, color);
-
-  bNode *node = node_ptr.data;
-  if (node->flag & NODE_MUTED) {
-    color[3] *= 0.25f;
-  }
-
-  if (selected) {
-    UI_GetThemeColor4fv(TH_TEXT_HI, outline_color);
-    outline_color[3] = 0.9f;
-  }
-  else {
-    copy_v4_fl(outline_color, 0.0f);
-    outline_color[3] = 0.6f;
-  }
+  int flags;
 
   /* sets shape flags */
   switch (sock->display_shape) {
@@ -768,8 +748,120 @@ static void node_socket_draw(const bContext *C,
   immAttr4fv(col_id, color);
   immAttr1u(shape_id, flags);
   immAttr1f(size_id, size);
-  immAttr4fv(outline_col_id, outline_color);
-  immVertex2f(pos_id, sock->locx, sock->locy);
+  immAttr4fv(outline_col_id, color_outline);
+  immVertex2f(pos_id, locx, locy);
+}
+
+static void node_socket_outline_color_get(bool selected, float r_outline_color[4])
+{
+  if (selected) {
+    UI_GetThemeColor4fv(TH_TEXT_HI, r_outline_color);
+    r_outline_color[3] = 0.9f;
+  }
+  else {
+    copy_v4_fl(r_outline_color, 0.0f);
+    r_outline_color[3] = 0.6f;
+  }
+}
+
+/* Usual convention here would be node_socket_get_color(), but that's already used (for setting a
+ * color property socket). */
+void node_socket_color_get(
+    bContext *C, bNodeTree *ntree, PointerRNA *node_ptr, bNodeSocket *sock, float r_color[4])
+{
+  PointerRNA ptr;
+
+  BLI_assert(RNA_struct_is_a(node_ptr->type, &RNA_Node));
+  RNA_pointer_create((ID *)ntree, &RNA_NodeSocket, sock, &ptr);
+
+  sock->typeinfo->draw_color(C, &ptr, node_ptr, r_color);
+
+  bNode *node = node_ptr->data;
+  if (node->flag & NODE_MUTED) {
+    r_color[3] *= 0.25f;
+  }
+}
+
+static void node_socket_draw_nested(const bContext *C,
+                                    bNodeTree *ntree,
+                                    PointerRNA *node_ptr,
+                                    bNodeSocket *sock,
+                                    uint pos_id,
+                                    uint col_id,
+                                    uint shape_id,
+                                    uint size_id,
+                                    uint outline_col_id,
+                                    float size,
+                                    bool selected)
+{
+  float color[4];
+  float outline_color[4];
+
+  node_socket_color_get((bContext *)C, ntree, node_ptr, sock, color);
+  node_socket_outline_color_get(selected, outline_color);
+
+  node_socket_draw(sock,
+                   color,
+                   outline_color,
+                   size,
+                   sock->locx,
+                   sock->locy,
+                   pos_id,
+                   col_id,
+                   shape_id,
+                   size_id,
+                   outline_col_id);
+}
+
+/**
+ * Draw a single node socket at default size.
+ * \note this is only called from external code, internally #node_socket_draw_nested() is used for
+ *       optimized drawing of multiple/all sockets of a node.
+ */
+void ED_node_socket_draw(bNodeSocket *sock, const rcti *rect, const float color[4], float scale)
+{
+  const float size = 2.25f * NODE_SOCKSIZE * scale;
+  rcti draw_rect = *rect;
+  float outline_color[4] = {0};
+
+  node_socket_outline_color_get(sock->flag & SELECT, outline_color);
+
+  BLI_rcti_resize(&draw_rect, size, size);
+
+  GPUVertFormat *format = immVertexFormat();
+  uint pos_id = GPU_vertformat_attr_add(format, "pos", GPU_COMP_F32, 2, GPU_FETCH_FLOAT);
+  uint col_id = GPU_vertformat_attr_add(format, "color", GPU_COMP_F32, 4, GPU_FETCH_FLOAT);
+  uint shape_id = GPU_vertformat_attr_add(format, "flags", GPU_COMP_U32, 1, GPU_FETCH_INT);
+  uint size_id = GPU_vertformat_attr_add(format, "size", GPU_COMP_F32, 1, GPU_FETCH_FLOAT);
+  uint outline_col_id = GPU_vertformat_attr_add(
+      format, "outlineColor", GPU_COMP_F32, 4, GPU_FETCH_FLOAT);
+
+  gpuPushAttr(GPU_BLEND_BIT);
+  GPU_blend(true);
+  GPU_program_point_size(true);
+
+  immBindBuiltinProgram(GPU_SHADER_KEYFRAME_DIAMOND);
+  immUniform1f("outline_scale", 0.7f);
+  immUniform2f("ViewportSize", -1.0f, -1.0f);
+
+  /* Single point */
+  immBegin(GPU_PRIM_POINTS, 1);
+  node_socket_draw(sock,
+                   color,
+                   outline_color,
+                   BLI_rcti_size_y(&draw_rect),
+                   BLI_rcti_cent_x(&draw_rect),
+                   BLI_rcti_cent_y(&draw_rect),
+                   pos_id,
+                   col_id,
+                   shape_id,
+                   size_id,
+                   outline_col_id);
+  immEnd();
+
+  immUnbindProgram();
+  GPU_program_point_size(false);
+  gpuPopAttr();
 }
 
 /* **************  Socket callbacks *********** */
@@ -962,17 +1054,17 @@ void node_draw_sockets(View2D *v2d,
       continue;
     }
 
-    node_socket_draw(C,
-                     ntree,
-                     node_ptr,
-                     sock,
-                     pos_id,
-                     col_id,
-                     shape_id,
-                     size_id,
-                     outline_col_id,
-                     scale,
-                     selected);
+    node_socket_draw_nested(C,
+                            ntree,
+                            &node_ptr,
+                            sock,
+                            pos_id,
+                            col_id,
+                            shape_id,
+                            size_id,
+                            outline_col_id,
+                            scale,
+                            selected);
   }
 
   /* socket outputs */
@@ -987,17 +1079,17 @@ void node_draw_sockets(View2D *v2d,
         continue;
       }
 
-      node_socket_draw(C,
-                       ntree,
-                       node_ptr,
-                       sock,
-                       pos_id,
-                       col_id,
-                       shape_id,
-                       size_id,
-                       outline_col_id,
-                       scale,
-                       selected);
+      node_socket_draw_nested(C,
+                              ntree,
+                              &node_ptr,
+                              sock,
+                              pos_id,
+                              col_id,
+                              shape_id,
+                              size_id,
+                              outline_col_id,
+                              scale,
+                              selected);
     }
   }
 
@@ -1020,17 +1112,17 @@ void node_draw_sockets(View2D *v2d,
           continue;
         }
         if (select_all || (sock->flag & SELECT)) {
-          node_socket_draw(C,
-                           ntree,
-                           node_ptr,
-                           sock,
-                           pos_id,
-                           col_id,
-                           shape_id,
-                           size_id,
-                           outline_col_id,
-                           scale,
-                           selected);
+          node_socket_draw_nested(C,
+                                  ntree,
+                                  &node_ptr,
+                                  sock,
+                                  pos_id,
+                                  col_id,
+                                  shape_id,
+                                  size_id,
+                                  outline_col_id,
+                                  scale,
+                                  selected);
           if (--selected_input_len == 0) {
             break; /* stop as soon as last one is drawn */
           }
@@ -1045,17 +1137,17 @@ void node_draw_sockets(View2D *v2d,
           continue;
         }
         if (select_all || (sock->flag & SELECT)) {
-          node_socket_draw(C,
-                           ntree,
-                           node_ptr,
-                           sock,
-                           pos_id,
-                           col_id,
-                           shape_id,
-                           size_id,
-                           outline_col_id,
-                           scale,
-                           selected);
+          node_socket_draw_nested(C,
+                                  ntree,
+                                  &node_ptr,
+                                  sock,
+                                  pos_id,
+                                  col_id,
+                                  shape_id,
+                                  size_id,
+                                  outline_col_id,
+                                  scale,
+                                  selected);
           if (--selected_output_len == 0) {
             break; /* stop as soon as last one is drawn */
           }