GP: Include option to render layers by view layer

This allows to make composition getting each grease pencil layer in a different render output.

3 files changed, 16 insertions, 0 deletions

diff --git a/source/blender/draw/engines/gpencil/gpencil_draw_utils.c b/source/blender/draw/engines/gpencil/gpencil_draw_utils.c
index 641229446b9..c980e1791db 100644
--- a/source/blender/draw/engines/gpencil/gpencil_draw_utils.c
+++ b/source/blender/draw/engines/gpencil/gpencil_draw_utils.c
@@ -1244,6 +1244,8 @@ void DRW_gpencil_populate_datablock(
 {
 	GPENCIL_StorageList *stl = ((GPENCIL_Data *)vedata)->stl;
 	const DRWContextState *draw_ctx = DRW_context_state_get();
+	const ViewLayer *view_layer = DEG_get_evaluated_view_layer(draw_ctx->depsgraph);
+
 	bGPdata *gpd_eval = (bGPdata *)ob->data;
 	bGPdata *gpd = (bGPdata *)DEG_get_original_id(&gpd_eval->id);
 
@@ -1278,6 +1280,14 @@ void DRW_gpencil_populate_datablock(
 		/* don't draw layer if hidden */
 		if (gpl->flag & GP_LAYER_HIDE)
 			continue;
+
+		/* filter view layer to gp layers in the same view layer (for compo) */
+		if ((stl->storage->is_render) && (gpl->viewlayername[0] != '\0')) {
+			if (!STREQ(view_layer->name, gpl->viewlayername)) {
+				continue;
+			}
+		}
+
 		if ((!time_remap) || (stl->storage->simplify_modif)) {
 			gpf = BKE_gpencil_layer_getframe(gpl, cfra_eval, GP_GETFRAME_USE_PREV);
 		}
diff --git a/source/blender/makesdna/DNA_gpencil_types.h b/source/blender/makesdna/DNA_gpencil_types.h
index 54559ce89f7..2c59dd899a9 100644
--- a/source/blender/makesdna/DNA_gpencil_types.h
+++ b/source/blender/makesdna/DNA_gpencil_types.h
@@ -270,6 +270,7 @@ typedef struct bGPDlayer {
 	short line_change;      /* Thickness adjustment */
 	float tintcolor[4];     /* Color used to tint layer, alpha value is used as factor */
 	float opacity;          /* Opacity of the layer */
+	char viewlayername[64]; /* Name of the layer used to filter render output */
 
 	bGPDlayer_Runtime runtime;
 } bGPDlayer;
diff --git a/source/blender/makesrna/intern/rna_gpencil.c b/source/blender/makesrna/intern/rna_gpencil.c
index de31c884b6b..33100c21180 100644
--- a/source/blender/makesrna/intern/rna_gpencil.c
+++ b/source/blender/makesrna/intern/rna_gpencil.c
@@ -1100,6 +1100,11 @@ static void rna_def_gpencil_layer(BlenderRNA *brna)
 	RNA_def_property_ui_text(prop, "Pass Index", "Index number for the \"Layer Index\" pass");
 	RNA_def_property_update(prop, NC_GPENCIL | ND_DATA, "rna_GPencil_update");
 
+	prop = RNA_def_property(srna, "viewlayer_render", PROP_STRING, PROP_NONE);
+	RNA_def_property_string_sdna(prop, NULL, "viewlayername");
+	RNA_def_property_ui_text(prop, "ViewLayer",
+		"Only include Layer in this View Layer render output (leave blank to include always)");
+
 	/* Flags */
 	prop = RNA_def_property(srna, "hide", PROP_BOOLEAN, PROP_NONE);
 	RNA_def_property_boolean_sdna(prop, NULL, "flag", GP_LAYER_HIDE);