Cleanup: Use references in node editor, other improvements

This helps to tell when a pointer is expected to be null, and avoid
overly verbose code when dereferencing. This commit also includes
a few other cleanups in this area:
 - Use const in a few places
 - Use `float2` instead of `float[2]`
 - Remove some unnecessary includes and old code
The change can be continued further in the future.

1 files changed, 43 insertions, 44 deletions

diff --git a/source/blender/editors/space_node/node_add.cc b/source/blender/editors/space_node/node_add.cc
index 2e3579caaa1..5276cc39e83 100644
--- a/source/blender/editors/space_node/node_add.cc
+++ b/source/blender/editors/space_node/node_add.cc
@@ -67,19 +67,19 @@
  * Can be used with both custom and static nodes,
  * if `idname == nullptr` the static int type will be used instead.
  */
-bNode *node_add_node(const bContext *C, const char *idname, int type, float locx, float locy)
+bNode *node_add_node(const bContext &C, const char *idname, int type, float locx, float locy)
 {
-  SpaceNode *snode = CTX_wm_space_node(C);
-  Main *bmain = CTX_data_main(C);
+  SpaceNode &snode = *CTX_wm_space_node(&C);
+  Main &bmain = *CTX_data_main(&C);
   bNode *node = nullptr;
 
   node_deselect_all(snode);
 
   if (idname) {
-    node = nodeAddNode(C, snode->edittree, idname);
+    node = nodeAddNode(&C, snode.edittree, idname);
   }
   else {
-    node = nodeAddStaticNode(C, snode->edittree, type);
+    node = nodeAddStaticNode(&C, snode.edittree, type);
   }
   BLI_assert(node && node->typeinfo);
 
@@ -89,13 +89,13 @@ bNode *node_add_node(const bContext *C, const char *idname, int type, float locx
 
   nodeSetSelected(node, true);
 
-  ntreeUpdateTree(bmain, snode->edittree);
-  ED_node_set_active(bmain, snode, snode->edittree, node, nullptr);
+  ntreeUpdateTree(&bmain, snode.edittree);
+  ED_node_set_active(&bmain, &snode, snode.edittree, node, nullptr);
 
   snode_update(snode, node);
 
-  if (snode->nodetree->type == NTREE_TEXTURE) {
-    ntreeTexCheckCyclics(snode->edittree);
+  if (snode.nodetree->type == NTREE_TEXTURE) {
+    ntreeTexCheckCyclics(snode.edittree);
   }
 
   return node;
@@ -107,7 +107,7 @@ bNode *node_add_node(const bContext *C, const char *idname, int type, float locx
 /** \name Add Reroute Operator
  * \{ */
 
-static bool add_reroute_intersect_check(bNodeLink *link,
+static bool add_reroute_intersect_check(const bNodeLink &link,
                                         float mcoords[][2],
                                         int tot,
                                         float result[2])
@@ -224,9 +224,9 @@ static bNodeSocketLink *add_reroute_do_socket_section(bContext *C,
 
 static int add_reroute_exec(bContext *C, wmOperator *op)
 {
-  SpaceNode *snode = CTX_wm_space_node(C);
-  ARegion *region = CTX_wm_region(C);
-  bNodeTree *ntree = snode->edittree;
+  SpaceNode &snode = *CTX_wm_space_node(C);
+  ARegion &region = *CTX_wm_region(C);
+  bNodeTree &ntree = *snode.edittree;
   float mcoords[256][2];
   int i = 0;
 
@@ -236,7 +236,7 @@ static int add_reroute_exec(bContext *C, wmOperator *op)
 
     RNA_float_get_array(&itemptr, "loc", loc);
     UI_view2d_region_to_view(
-        &region->v2d, (short)loc[0], (short)loc[1], &mcoords[i][0], &mcoords[i][1]);
+        &region.v2d, (short)loc[0], (short)loc[1], &mcoords[i][0], &mcoords[i][1]);
     i++;
     if (i >= 256) {
       break;
@@ -246,7 +246,6 @@ static int add_reroute_exec(bContext *C, wmOperator *op)
 
   if (i > 1) {
     ListBase output_links, input_links;
-    bNodeLink *link;
     bNodeSocketLink *socklink;
     float insert_point[2];
 
@@ -259,11 +258,11 @@ static int add_reroute_exec(bContext *C, wmOperator *op)
     BLI_listbase_clear(&output_links);
     BLI_listbase_clear(&input_links);
 
-    for (link = (bNodeLink *)ntree->links.first; link; link = link->next) {
-      if (node_link_is_hidden_or_dimmed(&region->v2d, link)) {
+    LISTBASE_FOREACH (bNodeLink *, link, &ntree.links) {
+      if (node_link_is_hidden_or_dimmed(region.v2d, *link)) {
         continue;
       }
-      if (add_reroute_intersect_check(link, mcoords, i, insert_point)) {
+      if (add_reroute_intersect_check(*link, mcoords, i, insert_point)) {
         add_reroute_insert_socket_link(&output_links, link->fromsock, link, insert_point);
         add_reroute_insert_socket_link(&input_links, link->tosock, link, insert_point);
 
@@ -288,9 +287,9 @@ static int add_reroute_exec(bContext *C, wmOperator *op)
     BLI_freelistN(&input_links);
 
     /* always last */
-    ntreeUpdateTree(CTX_data_main(C), ntree);
-    snode_notify(C, snode);
-    snode_dag_update(C, snode);
+    ntreeUpdateTree(CTX_data_main(C), &ntree);
+    snode_notify(*C, snode);
+    snode_dag_update(*C, snode);
 
     return OPERATOR_FINISHED;
   }
@@ -377,7 +376,7 @@ static int node_add_group_exec(bContext *C, wmOperator *op)
 
   ED_preview_kill_jobs(CTX_wm_manager(C), CTX_data_main(C));
 
-  bNode *group_node = node_add_node(C,
+  bNode *group_node = node_add_node(*C,
                                     node_group_idname(C),
                                     (node_group->type == NTREE_CUSTOM) ? NODE_CUSTOM_GROUP :
                                                                          NODE_GROUP,
@@ -395,8 +394,8 @@ static int node_add_group_exec(bContext *C, wmOperator *op)
   ntreeUpdateTree(bmain, node_group);
   ntreeUpdateTree(bmain, ntree);
 
-  snode_notify(C, snode);
-  snode_dag_update(C, snode);
+  snode_notify(*C, *snode);
+  snode_dag_update(*C, *snode);
 
   return OPERATOR_FINISHED;
 }
@@ -469,7 +468,7 @@ static int node_add_object_exec(bContext *C, wmOperator *op)
   ED_preview_kill_jobs(CTX_wm_manager(C), CTX_data_main(C));
 
   bNode *object_node = node_add_node(
-      C, nullptr, GEO_NODE_OBJECT_INFO, snode->runtime->cursor[0], snode->runtime->cursor[1]);
+      *C, nullptr, GEO_NODE_OBJECT_INFO, snode->runtime->cursor[0], snode->runtime->cursor[1]);
   if (!object_node) {
     BKE_report(op->reports, RPT_WARNING, "Could not add node object");
     return OPERATOR_CANCELLED;
@@ -488,8 +487,8 @@ static int node_add_object_exec(bContext *C, wmOperator *op)
   nodeSetActive(ntree, object_node);
   ntreeUpdateTree(bmain, ntree);
 
-  snode_notify(C, snode);
-  snode_dag_update(C, snode);
+  snode_notify(*C, *snode);
+  snode_dag_update(*C, *snode);
 
   ED_node_tag_update_nodetree(bmain, ntree, object_node);
   DEG_relations_tag_update(bmain);
@@ -580,7 +579,7 @@ static int node_add_texture_exec(bContext *C, wmOperator *op)
 
   ED_preview_kill_jobs(CTX_wm_manager(C), CTX_data_main(C));
 
-  bNode *texture_node = node_add_node(C,
+  bNode *texture_node = node_add_node(*C,
                                       nullptr,
                                       GEO_NODE_LEGACY_ATTRIBUTE_SAMPLE_TEXTURE,
                                       snode->runtime->cursor[0],
@@ -596,8 +595,8 @@ static int node_add_texture_exec(bContext *C, wmOperator *op)
   nodeSetActive(ntree, texture_node);
   ntreeUpdateTree(bmain, ntree);
 
-  snode_notify(C, snode);
-  snode_dag_update(C, snode);
+  snode_notify(*C, *snode);
+  snode_dag_update(*C, *snode);
   DEG_relations_tag_update(bmain);
 
   ED_node_tag_update_nodetree(bmain, ntree, texture_node);
@@ -680,8 +679,8 @@ static Collection *node_add_collection_get_and_poll_collection_node_tree(Main *b
 static int node_add_collection_exec(bContext *C, wmOperator *op)
 {
   Main *bmain = CTX_data_main(C);
-  SpaceNode *snode = CTX_wm_space_node(C);
-  bNodeTree *ntree = snode->edittree;
+  SpaceNode &snode = *CTX_wm_space_node(C);
+  bNodeTree *ntree = snode.edittree;
   Collection *collection;
 
   if (!(collection = node_add_collection_get_and_poll_collection_node_tree(bmain, op))) {
@@ -691,7 +690,7 @@ static int node_add_collection_exec(bContext *C, wmOperator *op)
   ED_preview_kill_jobs(CTX_wm_manager(C), CTX_data_main(C));
 
   bNode *collection_node = node_add_node(
-      C, nullptr, GEO_NODE_COLLECTION_INFO, snode->runtime->cursor[0], snode->runtime->cursor[1]);
+      *C, nullptr, GEO_NODE_COLLECTION_INFO, snode.runtime->cursor[0], snode.runtime->cursor[1]);
   if (!collection_node) {
     BKE_report(op->reports, RPT_WARNING, "Could not add node collection");
     return OPERATOR_CANCELLED;
@@ -710,8 +709,8 @@ static int node_add_collection_exec(bContext *C, wmOperator *op)
   nodeSetActive(ntree, collection_node);
   ntreeUpdateTree(bmain, ntree);
 
-  snode_notify(C, snode);
-  snode_dag_update(C, snode);
+  snode_notify(*C, snode);
+  snode_dag_update(*C, snode);
   DEG_relations_tag_update(bmain);
 
   ED_node_tag_update_nodetree(bmain, ntree, collection_node);
@@ -788,7 +787,7 @@ static bool node_add_file_poll(bContext *C)
 static int node_add_file_exec(bContext *C, wmOperator *op)
 {
   Main *bmain = CTX_data_main(C);
-  SpaceNode *snode = CTX_wm_space_node(C);
+  SpaceNode &snode = *CTX_wm_space_node(C);
   bNode *node;
   Image *ima;
   int type = 0;
@@ -798,7 +797,7 @@ static int node_add_file_exec(bContext *C, wmOperator *op)
     return OPERATOR_CANCELLED;
   }
 
-  switch (snode->nodetree->type) {
+  switch (snode.nodetree->type) {
     case NTREE_SHADER:
       type = SH_NODE_TEX_IMAGE;
       break;
@@ -817,7 +816,7 @@ static int node_add_file_exec(bContext *C, wmOperator *op)
 
   ED_preview_kill_jobs(CTX_wm_manager(C), CTX_data_main(C));
 
-  node = node_add_node(C, nullptr, type, snode->runtime->cursor[0], snode->runtime->cursor[1]);
+  node = node_add_node(*C, nullptr, type, snode.runtime->cursor[0], snode.runtime->cursor[1]);
 
   if (!node) {
     BKE_report(op->reports, RPT_WARNING, "Could not add an image node");
@@ -841,8 +840,8 @@ static int node_add_file_exec(bContext *C, wmOperator *op)
     WM_event_add_notifier(C, NC_IMAGE | NA_EDITED, ima);
   }
 
-  snode_notify(C, snode);
-  snode_dag_update(C, snode);
+  snode_notify(*C, snode);
+  snode_dag_update(*C, snode);
   DEG_relations_tag_update(bmain);
 
   return OPERATOR_FINISHED;
@@ -923,7 +922,7 @@ static bool node_add_mask_poll(bContext *C)
 static int node_add_mask_exec(bContext *C, wmOperator *op)
 {
   Main *bmain = CTX_data_main(C);
-  SpaceNode *snode = CTX_wm_space_node(C);
+  SpaceNode &snode = *CTX_wm_space_node(C);
   bNode *node;
 
   ID *mask = node_add_mask_get_and_poll_mask(bmain, op);
@@ -934,7 +933,7 @@ static int node_add_mask_exec(bContext *C, wmOperator *op)
   ED_preview_kill_jobs(CTX_wm_manager(C), CTX_data_main(C));
 
   node = node_add_node(
-      C, nullptr, CMP_NODE_MASK, snode->runtime->cursor[0], snode->runtime->cursor[1]);
+      *C, nullptr, CMP_NODE_MASK, snode.runtime->cursor[0], snode.runtime->cursor[1]);
 
   if (!node) {
     BKE_report(op->reports, RPT_WARNING, "Could not add a mask node");
@@ -944,8 +943,8 @@ static int node_add_mask_exec(bContext *C, wmOperator *op)
   node->id = mask;
   id_us_plus(mask);
 
-  snode_notify(C, snode);
-  snode_dag_update(C, snode);
+  snode_notify(*C, snode);
+  snode_dag_update(*C, snode);
   DEG_relations_tag_update(bmain);
 
   return OPERATOR_FINISHED;