Code cleanup: Define a dedicated "channel_role" field for animchannel types

This makes it easier for finding the active or first selected channel
(where actual data channels need to be favoured over expanders - which come
first), as previously, long switch statements were needed everytime.

3 files changed, 44 insertions, 58 deletions

diff --git a/source/blender/editors/animation/anim_channels_defines.c b/source/blender/editors/animation/anim_channels_defines.c
index 97e18fff32e..1cd1a26678d 100644
--- a/source/blender/editors/animation/anim_channels_defines.c
+++ b/source/blender/editors/animation/anim_channels_defines.c
@@ -485,6 +485,7 @@ static void *acf_summary_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings s
 static bAnimChannelType ACF_SUMMARY = 
 {
 	"Summary",                          /* type name */
+	ACHANNEL_ROLE_EXPANDER,             /* role */
 
 	acf_summary_color,                  /* backdrop color */
 	acf_summary_backdrop,               /* backdrop */
@@ -586,6 +587,7 @@ static void *acf_scene_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings set
 static bAnimChannelType ACF_SCENE = 
 {
 	"Scene",                        /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 
 	acf_generic_root_color,         /* backdrop color */
 	acf_generic_root_backdrop,      /* backdrop */
@@ -730,6 +732,7 @@ static void *acf_object_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings se
 static bAnimChannelType ACF_OBJECT = 
 {
 	"Object",                       /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_root_color,         /* backdrop color */
 	acf_generic_root_backdrop,      /* backdrop */
@@ -879,6 +882,7 @@ static void *acf_group_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings UNU
 static bAnimChannelType ACF_GROUP = 
 {
 	"Group",                        /* type name */
+	ACHANNEL_ROLE_CHANNEL,          /* role */
 	
 	acf_group_color,                /* backdrop color */
 	acf_group_backdrop,             /* backdrop */
@@ -987,6 +991,7 @@ static void *acf_fcurve_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings UN
 static bAnimChannelType ACF_FCURVE = 
 {
 	"F-Curve",                      /* type name */
+	ACHANNEL_ROLE_CHANNEL,          /* role */
 	
 	acf_generic_channel_color,      /* backdrop color */
 	acf_generic_channel_backdrop,   /* backdrop */
@@ -1071,6 +1076,7 @@ static void *acf_fillactd_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings
 static bAnimChannelType ACF_FILLACTD = 
 {
 	"Ob-Action Filler",             /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -1150,6 +1156,7 @@ static void *acf_filldrivers_setting_ptr(bAnimListElem *ale, eAnimChannel_Settin
 static bAnimChannelType ACF_FILLDRIVERS = 
 {
 	"Drivers Filler",               /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -1227,6 +1234,7 @@ static void *acf_dsmat_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings set
 static bAnimChannelType ACF_DSMAT =
 {
 	"Material Data Expander",       /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -1303,6 +1311,7 @@ static void *acf_dslam_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings set
 static bAnimChannelType ACF_DSLAM =
 {
 	"Lamp Expander",                /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -1386,6 +1395,7 @@ static void *acf_dstex_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings set
 static bAnimChannelType ACF_DSTEX =
 {
 	"Texture Data Expander",        /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -1462,6 +1472,7 @@ static void *acf_dscam_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings set
 static bAnimChannelType ACF_DSCAM =
 {
 	"Camera Expander",              /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -1548,6 +1559,7 @@ static void *acf_dscur_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings set
 static bAnimChannelType ACF_DSCUR =
 {
 	"Curve Expander",               /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -1624,6 +1636,7 @@ static void *acf_dsskey_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings se
 static bAnimChannelType ACF_DSSKEY =
 {
 	"Shape Key Expander",           /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -1700,6 +1713,7 @@ static void *acf_dswor_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings set
 static bAnimChannelType ACF_DSWOR =
 {
 	"World Expander",               /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -1776,6 +1790,7 @@ static void *acf_dspart_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings se
 static bAnimChannelType ACF_DSPART =
 {
 	"Particle Data Expander",       /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -1852,6 +1867,7 @@ static void *acf_dsmball_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings s
 static bAnimChannelType ACF_DSMBALL =
 {
 	"Metaball Expander",            /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -1928,6 +1944,7 @@ static void *acf_dsarm_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings set
 static bAnimChannelType ACF_DSARM =
 {
 	"Armature Expander",            /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -2015,6 +2032,7 @@ static void *acf_dsntree_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings s
 static bAnimChannelType ACF_DSNTREE =
 {
 	"Node Tree Expander",           /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -2091,6 +2109,7 @@ static void *acf_dslinestyle_setting_ptr(bAnimListElem *ale, eAnimChannel_Settin
 static bAnimChannelType ACF_DSLINESTYLE =
 {
 	"Line Style Expander",			/* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,	/* backdrop color */
 	acf_generic_dataexpand_backdrop,/* backdrop */
@@ -2167,6 +2186,7 @@ static void *acf_dsmesh_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings se
 static bAnimChannelType ACF_DSMESH =
 {
 	"Mesh Expander",                /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -2243,6 +2263,7 @@ static void *acf_dslat_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings set
 static bAnimChannelType ACF_DSLAT =
 {
 	"Lattice Expander",             /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -2319,6 +2340,7 @@ static void *acf_dsspk_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings set
 static bAnimChannelType ACF_DSSPK =
 {
 	"Speaker Expander",             /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_generic_dataexpand_color,   /* backdrop color */
 	acf_generic_dataexpand_backdrop, /* backdrop */
@@ -2426,6 +2448,7 @@ static void *acf_shapekey_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings
 static bAnimChannelType ACF_SHAPEKEY =
 {
 	"Shape Key",                    /* type name */
+	ACHANNEL_ROLE_CHANNEL,          /* role */
 	
 	acf_generic_channel_color,      /* backdrop color */
 	acf_generic_channel_backdrop,   /* backdrop */
@@ -2502,6 +2525,7 @@ static void *acf_gpd_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings UNUSE
 static bAnimChannelType ACF_GPD = 
 {
 	"GPencil Datablock",            /* type name */
+	ACHANNEL_ROLE_EXPANDER,         /* role */
 	
 	acf_gpd_color,                  /* backdrop color */
 	acf_group_backdrop,             /* backdrop */
@@ -2591,6 +2615,7 @@ static void *acf_gpl_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings UNUSE
 static bAnimChannelType ACF_GPL = 
 {
 	"GPencil Layer",                /* type name */
+	ACHANNEL_ROLE_CHANNEL,          /* role */
 	
 	acf_generic_channel_color,      /* backdrop color */
 	acf_generic_channel_backdrop,   /* backdrop */
@@ -2668,6 +2693,7 @@ static void *acf_mask_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings UNUS
 static bAnimChannelType ACF_MASKDATA =
 {
 	"Mask Datablock",                /* type name */
+	ACHANNEL_ROLE_EXPANDER,          /* role */
 	
 	acf_mask_color,                  /* backdrop color */
 	acf_group_backdrop,              /* backdrop */
@@ -2754,6 +2780,7 @@ static void *acf_masklay_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings U
 static bAnimChannelType ACF_MASKLAYER =
 {
 	"Mask Layer",                   /* type name */
+	ACHANNEL_ROLE_CHANNEL,          /* role */
 	
 	acf_generic_channel_color,      /* backdrop color */
 	acf_generic_channel_backdrop,   /* backdrop */
@@ -2892,6 +2919,7 @@ static void *acf_nlatrack_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings
 static bAnimChannelType ACF_NLATRACK = 
 {
 	"NLA Track",                    /* type name */
+	ACHANNEL_ROLE_CHANNEL,          /* role */
 	
 	acf_nlatrack_color,             /* backdrop color */
 	acf_generic_channel_backdrop,   /* backdrop */
@@ -3060,6 +3088,7 @@ static void *acf_nlaaction_setting_ptr(bAnimListElem *ale, eAnimChannel_Settings
 static bAnimChannelType ACF_NLAACTION = 
 {
 	"NLA Active Action",            /* type name */
+	ACHANNEL_ROLE_CHANNEL,          /* role */
 	
 	acf_nlaaction_color,            /* backdrop color (NOTE: the backdrop handles this too, since it needs special hacks) */
 	acf_nlaaction_backdrop,         /* backdrop */
diff --git a/source/blender/editors/include/ED_anim_api.h b/source/blender/editors/include/ED_anim_api.h
index c6b8d879180..10f3f1bef4c 100644
--- a/source/blender/editors/include/ED_anim_api.h
+++ b/source/blender/editors/include/ED_anim_api.h
@@ -163,7 +163,7 @@ typedef enum eAnim_ChannelType {
 	
 	ANIMTYPE_GPDATABLOCK,
 	ANIMTYPE_GPLAYER,
-
+	
 	ANIMTYPE_MASKDATABLOCK,
 	ANIMTYPE_MASKLAYER,
 	
@@ -362,6 +362,13 @@ bool ANIM_animdata_context_getdata(bAnimContext *ac);
 
 /* ------------------------ Drawing TypeInfo -------------------------- */
 
+/* role or level of animchannel in the hierarchy */
+typedef enum eAnimChannel_Role {
+	ACHANNEL_ROLE_EXPANDER = -1,    /* datablock expander - a "composite" channel type */
+	ACHANNEL_ROLE_SPECIAL  = 0,     /* special purposes - not generally for hierarchy processing */
+	ACHANNEL_ROLE_CHANNEL  = 1      /* data channel - a channel representing one of the actual building blocks of channels */
+} eAnimChannel_Role;
+
 /* flag-setting behavior */
 typedef enum eAnimChannels_SetFlag {
 	ACHANNEL_SETFLAG_CLEAR  = 0,     /* turn off */
@@ -384,11 +391,13 @@ typedef enum eAnimChannel_Settings {
 
 /* Drawing, mouse handling, and flag setting behavior... */
 typedef struct bAnimChannelType {
-	/* type data */
+	/* -- Type data -- */
 	/* name of the channel type, for debugging */
 	const char *channel_type_name;
+	/* "level" or role in hierarchy - for finding the active channel */
+	eAnimChannel_Role channel_role;
 	
-	/* drawing */
+	/* -- Drawing -- */
 	/* get RGB color that is used to draw the majority of the backdrop */
 	void (*get_backdrop_color)(bAnimContext *ac, bAnimListElem *ale, float r_color[3]);
 	/* draw backdrop strip for channel */
@@ -405,7 +414,7 @@ typedef struct bAnimChannelType {
 	/* get icon (for channel lists) */
 	int (*icon)(bAnimListElem *ale);
 	
-	/* settings */
+	/* -- Settings -- */
 	/* check if the given setting is valid in the current context */
 	bool (*has_setting)(bAnimContext *ac, bAnimListElem *ale, eAnimChannel_Settings setting);
 	/* get the flag used for this setting */
diff --git a/source/blender/editors/space_action/action_edit.c b/source/blender/editors/space_action/action_edit.c
index f38c94a2d59..92e727fc2d7 100644
--- a/source/blender/editors/space_action/action_edit.c
+++ b/source/blender/editors/space_action/action_edit.c
@@ -395,64 +395,12 @@ static bool actkeys_channels_get_selected_extents(bAnimContext *ac, float *min,
 			*max = (float)(y + ACHANNEL_HEIGHT_HALF);
 			
 			/* is this high enough priority yet? */
-			// TODO: refactor this check out into a utility function, and share this with other places which do stuff like this
-			switch (ale->type) {
-				/* datablock expanders - ignore unless nothing else comes along */
-				case ANIMTYPE_SUMMARY:
-					found = -1;
-					break;
-					
-				case ANIMTYPE_SCENE:
-				case ANIMTYPE_OBJECT:
-					found = -1;
-					break;
-				
-				case ANIMTYPE_FILLACTD:
-				case ANIMTYPE_FILLDRIVERS:
-				case ANIMTYPE_DSMAT:
-				case ANIMTYPE_DSLAM:
-				case ANIMTYPE_DSCAM:
-				case ANIMTYPE_DSCUR:
-				case ANIMTYPE_DSSKEY:
-				case ANIMTYPE_DSWOR:
-				case ANIMTYPE_DSNTREE:
-				case ANIMTYPE_DSPART:
-				case ANIMTYPE_DSMBALL:
-				case ANIMTYPE_DSARM:
-				case ANIMTYPE_DSMESH:
-				case ANIMTYPE_DSTEX:
-				case ANIMTYPE_DSLAT:
-				case ANIMTYPE_DSLINESTYLE:
-				case ANIMTYPE_DSSPK:
-					found = -1;
-					break;
-					
-				case ANIMTYPE_GPDATABLOCK:
-				case ANIMTYPE_MASKDATABLOCK:
-					found = -1;
-					break;
-				
-				
-				/* actual channels */
-				case ANIMTYPE_GROUP:
-				case ANIMTYPE_FCURVE:
-				case ANIMTYPE_SHAPEKEY:
-					found = 1;
-					break;
-				
-				case ANIMTYPE_GPLAYER:
-				case ANIMTYPE_MASKLAYER:
-					found = 1;
-					break;
-				
-				default: /* irrelevant */
-					break;
-			}
+			found = acf->channel_role;
 			
 			/* only stop our search when we've found an actual channel
 			 * - datablock expanders get less priority so that we don't abort prematurely
 			 */
-			if (found > 0) {
+			if (found == ACHANNEL_ROLE_CHANNEL) {
 				break;
 			}
 		}