GP: New Blend Layers functionality

Now it's possible define the blend mode between layers including the option to clamp the layer using underlying layers.

Also a new Simplify option has been added to disable blend layers.

2 files changed, 18 insertions, 1 deletions

diff --git a/source/blender/makesdna/DNA_gpencil_types.h b/source/blender/makesdna/DNA_gpencil_types.h
index 8a1bccc6957..cebdc4b29b9 100644
--- a/source/blender/makesdna/DNA_gpencil_types.h
+++ b/source/blender/makesdna/DNA_gpencil_types.h
@@ -269,6 +269,9 @@ typedef struct bGPDlayer {
 	float opacity;          /* Opacity of the layer */
 	char viewlayername[64]; /* Name of the layer used to filter render output */
 
+	int blend_mode;         /* blend modes */
+	char pad_[4];
+
 	bGPDlayer_Runtime runtime;
 } bGPDlayer;
 
@@ -292,6 +295,8 @@ typedef enum eGPDlayer_Flag {
 	GP_LAYER_VOLUMETRIC		= (1 << 10),
 	/* Unlock color */
 	GP_LAYER_UNLOCK_COLOR 	= (1 << 12),
+	/* Mask Layer */
+	GP_LAYER_USE_MASK = (1 << 13),
 } eGPDlayer_Flag;
 
 /* bGPDlayer->onion_flag */
@@ -300,6 +305,16 @@ typedef enum eGPDlayer_OnionFlag {
 	GP_LAYER_ONIONSKIN = (1 << 0),
 } eGPDlayer_OnionFlag;
 
+/* layer blend_mode */
+typedef enum eGPLayerBlendModes {
+	eGplBlendMode_Normal = 0,
+	eGplBlendMode_Overlay = 1,
+	eGplBlendMode_Add = 2,
+	eGplBlendMode_Subtract = 3,
+	eGplBlendMode_Multiply = 4,
+	eGplBlendMode_Divide = 5,
+} eGPLayerBlendModes;
+
 /* ***************************************** */
 /* GP Datablock */
 
diff --git a/source/blender/makesdna/DNA_scene_types.h b/source/blender/makesdna/DNA_scene_types.h
index 7ab4187de1a..e2cfd79ca93 100644
--- a/source/blender/makesdna/DNA_scene_types.h
+++ b/source/blender/makesdna/DNA_scene_types.h
@@ -2144,7 +2144,9 @@ typedef enum eGPencil_SimplifyFlags {
 	/* Remove fill external line */
 	SIMPLIFY_GPENCIL_REMOVE_FILL_LINE = (1 << 4),
 	/* Simplify Shader FX */
-	SIMPLIFY_GPENCIL_FX               = (1 << 5)
+	SIMPLIFY_GPENCIL_FX               = (1 << 5),
+	/* Simplify layer blending */
+	SIMPLIFY_GPENCIL_BLEND            = (1 << 6),
 } eGPencil_SimplifyFlags;
 
 /* ToolSettings.gpencil_*_align - Stroke Placement mode flags */