Note Editor: Auto-offset nodes on insertion

Implements "Auto-offset" (called "insert offset" in code) feature for Node Editor, developed during and after LSOC :)
Idea and sponsoring by Sebastian König, blendFX, Mathias Eimann, Mikavaa, Knick Design

When you drop a node with at least one input and one output socket onto a an existing connection between two nodes, Auto-offset will, depending on the direction setting, automatically and animated move the left or right and all of its following nodes away to make room for the new node.
The direction for offsetting can be toggled while you are moving the node by pressing „T“.

The auto-offset is enabled by default but can be disabled in the header of the node-editor. The offset margin can be changed in the editing section of the User Preferences.

Thanks a lot to the sponsors, and especially to Sebastian who helped *a lot* with this. That's how users can help developing Blender!

1 files changed, 19 insertions, 7 deletions

diff --git a/source/blender/makesdna/DNA_space_types.h b/source/blender/makesdna/DNA_space_types.h
index ab19273f087..2a066726d96 100644
--- a/source/blender/makesdna/DNA_space_types.h
+++ b/source/blender/makesdna/DNA_space_types.h
@@ -985,12 +985,17 @@ typedef struct SpaceNode {
 	int treetype DNA_DEPRECATED; /* treetype: as same nodetree->type */
 	int pad3;
 	
-	short texfrom;      /* texfrom object, world or brush */
-	short shaderfrom;   /* shader from object or world */
-	short recalc;       /* currently on 0/1, for auto compo */
-	short pad4;
-	ListBase linkdrag;  /* temporary data for modal linking operator */
-	
+	short texfrom;       /* texfrom object, world or brush */
+	short shaderfrom;    /* shader from object or world */
+	short recalc;        /* currently on 0/1, for auto compo */
+
+	char insert_ofs_dir; /* direction for offsetting nodes on insertion */
+	char pad4;
+
+	ListBase linkdrag;   /* temporary data for modal linking operator */
+	/* XXX hack for translate_attach op-macros to pass data from transform op to insert_offset op */
+	struct NodeInsertOfsData *iofsd; /* temporary data for node insert offset (in UI called Auto-offset) */
+
 	struct bGPdata *gpd;        /* grease-pencil data */
 } SpaceNode;
 
@@ -1006,8 +1011,9 @@ typedef enum eSpaceNode_Flag {
 	SNODE_AUTO_RENDER    = (1 << 5),
 	SNODE_SHOW_HIGHLIGHT = (1 << 6),
 //	SNODE_USE_HIDDEN_PREVIEW = (1 << 10), DNA_DEPRECATED December2013 
-	SNODE_NEW_SHADERS = (1 << 11),
+	SNODE_NEW_SHADERS    = (1 << 11),
 	SNODE_PIN            = (1 << 12),
+	SNODE_SKIP_INSOFFSET = (1 << 13), /* automatically offset following nodes in a chain on insertion */
 } eSpaceNode_Flag;
 
 /* snode->texfrom */
@@ -1025,6 +1031,12 @@ typedef enum eSpaceNode_ShaderFrom {
 	SNODE_SHADER_LINESTYLE = 2,
 } eSpaceNode_ShaderFrom;
 
+/* snode->insert_ofs_dir */
+enum {
+	SNODE_INSERTOFS_DIR_RIGHT = 0,
+	SNODE_INSERTOFS_DIR_LEFT  = 1,
+};
+
 /* Game Logic Editor ===================================== */
 
 /* Logic Editor */