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, 39 insertions, 41 deletions

diff --git a/source/blender/editors/space_node/node_view.cc b/source/blender/editors/space_node/node_view.cc
index 36b84bec7eb..1153b28bd82 100644
--- a/source/blender/editors/space_node/node_view.cc
+++ b/source/blender/editors/space_node/node_view.cc
@@ -62,25 +62,21 @@ using blender::StringRef;
 /** \name View All Operator
  * \{ */
 
-int space_node_view_flag(
-    bContext *C, SpaceNode *snode, ARegion *region, const int node_flag, const int smooth_viewtx)
+bool space_node_view_flag(
+    bContext &C, SpaceNode &snode, ARegion &region, const int node_flag, const int smooth_viewtx)
 {
-  bNode *node;
-  rctf cur_new;
-  float oldwidth, oldheight, width, height;
-  float oldasp, asp;
-  int tot = 0;
-  bool has_frame = false;
+  const float oldwidth = BLI_rctf_size_x(&region.v2d.cur);
+  const float oldheight = BLI_rctf_size_y(&region.v2d.cur);
 
-  oldwidth = BLI_rctf_size_x(&region->v2d.cur);
-  oldheight = BLI_rctf_size_y(&region->v2d.cur);
-
-  oldasp = oldwidth / oldheight;
+  const float old_aspect = oldwidth / oldheight;
 
+  rctf cur_new;
   BLI_rctf_init_minmax(&cur_new);
 
-  if (snode->edittree) {
-    for (node = (bNode *)snode->edittree->nodes.first; node; node = node->next) {
+  int tot = 0;
+  bool has_frame = false;
+  if (snode.edittree) {
+    LISTBASE_FOREACH (const bNode *, node, &snode.edittree->nodes) {
       if ((node->flag & node_flag) == node_flag) {
         BLI_rctf_union(&cur_new, &node->totr);
         tot++;
@@ -92,37 +88,39 @@ int space_node_view_flag(
     }
   }
 
-  if (tot) {
-    width = BLI_rctf_size_x(&cur_new);
-    height = BLI_rctf_size_y(&cur_new);
-    asp = width / height;
+  if (tot == 0) {
+    return false;
+  }
 
-    /* for single non-frame nodes, don't zoom in, just pan view,
-     * but do allow zooming out, this allows for big nodes to be zoomed out */
-    if ((tot == 1) && (has_frame == false) && ((oldwidth * oldheight) > (width * height))) {
-      /* center, don't zoom */
-      BLI_rctf_resize(&cur_new, oldwidth, oldheight);
+  const float width = BLI_rctf_size_x(&cur_new);
+  const float height = BLI_rctf_size_y(&cur_new);
+  const float new_aspect = width / height;
+
+  /* for single non-frame nodes, don't zoom in, just pan view,
+   * but do allow zooming out, this allows for big nodes to be zoomed out */
+  if ((tot == 1) && (has_frame == false) && ((oldwidth * oldheight) > (width * height))) {
+    /* center, don't zoom */
+    BLI_rctf_resize(&cur_new, oldwidth, oldheight);
+  }
+  else {
+    if (old_aspect < new_aspect) {
+      const float height_new = width / old_aspect;
+      cur_new.ymin = cur_new.ymin - height_new / 2.0f;
+      cur_new.ymax = cur_new.ymax + height_new / 2.0f;
     }
     else {
-      if (oldasp < asp) {
-        const float height_new = width / oldasp;
-        cur_new.ymin = cur_new.ymin - height_new / 2.0f;
-        cur_new.ymax = cur_new.ymax + height_new / 2.0f;
-      }
-      else {
-        const float width_new = height * oldasp;
-        cur_new.xmin = cur_new.xmin - width_new / 2.0f;
-        cur_new.xmax = cur_new.xmax + width_new / 2.0f;
-      }
-
-      /* add some padding */
-      BLI_rctf_scale(&cur_new, 1.1f);
+      const float width_new = height * old_aspect;
+      cur_new.xmin = cur_new.xmin - width_new / 2.0f;
+      cur_new.xmax = cur_new.xmax + width_new / 2.0f;
     }
 
-    UI_view2d_smooth_view(C, region, &cur_new, smooth_viewtx);
+    /* add some padding */
+    BLI_rctf_scale(&cur_new, 1.1f);
   }
 
-  return (tot != 0);
+  UI_view2d_smooth_view(&C, &region, &cur_new, smooth_viewtx);
+
+  return true;
 }
 
 static int node_view_all_exec(bContext *C, wmOperator *op)
@@ -135,7 +133,7 @@ static int node_view_all_exec(bContext *C, wmOperator *op)
   snode->xof = 0;
   snode->yof = 0;
 
-  if (space_node_view_flag(C, snode, region, 0, smooth_viewtx)) {
+  if (space_node_view_flag(*C, *snode, *region, 0, smooth_viewtx)) {
     return OPERATOR_FINISHED;
   }
   return OPERATOR_CANCELLED;
@@ -168,7 +166,7 @@ static int node_view_selected_exec(bContext *C, wmOperator *op)
   SpaceNode *snode = CTX_wm_space_node(C);
   const int smooth_viewtx = WM_operator_smooth_viewtx_get(op);
 
-  if (space_node_view_flag(C, snode, region, NODE_SELECT, smooth_viewtx)) {
+  if (space_node_view_flag(*C, *snode, *region, NODE_SELECT, smooth_viewtx)) {
     return OPERATOR_FINISHED;
   }
   return OPERATOR_CANCELLED;
@@ -738,7 +736,7 @@ static int space_node_view_geometry_nodes_legacy(bContext *C, SpaceNode *snode,
   }
 
   const int smooth_viewtx = WM_operator_smooth_viewtx_get(op);
-  if (space_node_view_flag(C, snode, region, NODE_SELECT, smooth_viewtx)) {
+  if (space_node_view_flag(*C, *snode, *region, NODE_SELECT, smooth_viewtx)) {
     return OPERATOR_FINISHED;
   }
   return OPERATOR_CANCELLED;