MetaBall support for Workbench + EEVEE

Note: Metaballs only support the first material slot. Splicing it per
material would create empty Batches. In order to overcome this we set
the batch for other materials to NULL. We added extra checks in EEVEE
and Workbench to not draw when the geom is NULL.

5 files changed, 26 insertions, 7 deletions

diff --git a/source/blender/draw/engines/eevee/eevee_engine.c b/source/blender/draw/engines/eevee/eevee_engine.c
index f159bf21d03..d7c6684f086 100644
--- a/source/blender/draw/engines/eevee/eevee_engine.c
+++ b/source/blender/draw/engines/eevee/eevee_engine.c
@@ -142,7 +142,7 @@ static void eevee_cache_populate(void *vedata, Object *ob)
 	}
 
 	if (DRW_check_object_visible_within_active_context(ob)) {
-		if (ELEM(ob->type, OB_MESH, OB_CURVE, OB_SURF, OB_FONT)) {
+		if (ELEM(ob->type, OB_MESH, OB_CURVE, OB_SURF, OB_FONT, OB_MBALL)) {
 			EEVEE_materials_cache_populate(vedata, sldata, ob, &cast_shadow);
 		}
 		else if (!USE_SCENE_LIGHT(draw_ctx->v3d)) {
diff --git a/source/blender/draw/engines/eevee/eevee_materials.c b/source/blender/draw/engines/eevee/eevee_materials.c
index 3ce60e0ed75..1a5c26f1c31 100644
--- a/source/blender/draw/engines/eevee/eevee_materials.c
+++ b/source/blender/draw/engines/eevee/eevee_materials.c
@@ -1406,7 +1406,7 @@ void EEVEE_materials_cache_populate(EEVEE_Data *vedata, EEVEE_ViewLayerData *sld
 	const bool is_default_mode_shader = is_sculpt_mode;
 
 	/* First get materials for this mesh. */
-	if (ELEM(ob->type, OB_MESH, OB_CURVE, OB_SURF, OB_FONT)) {
+	if (ELEM(ob->type, OB_MESH, OB_CURVE, OB_SURF, OB_FONT, OB_MBALL)) {
 		const int materials_len = MAX2(1, (is_sculpt_mode_draw ? 1 : ob->totcol));
 
 		struct DRWShadingGroup **shgrp_array = BLI_array_alloca(shgrp_array, materials_len);
@@ -1484,6 +1484,9 @@ void EEVEE_materials_cache_populate(EEVEE_Data *vedata, EEVEE_ViewLayerData *sld
 		        &auto_layer_count);
 		if (mat_geom) {
 			for (int i = 0; i < materials_len; ++i) {
+				if (mat_geom[i] == NULL) {
+					continue;
+				}
 				EEVEE_ObjectEngineData *oedata = NULL;
 				Material *ma = give_current_material(ob, i + 1);
 
diff --git a/source/blender/draw/engines/eevee/eevee_render.c b/source/blender/draw/engines/eevee/eevee_render.c
index 76887145ad2..5d31488d75f 100644
--- a/source/blender/draw/engines/eevee/eevee_render.c
+++ b/source/blender/draw/engines/eevee/eevee_render.c
@@ -150,7 +150,7 @@ void EEVEE_render_cache(
 	}
 
 	if (DRW_check_object_visible_within_active_context(ob)) {
-		if (ELEM(ob->type, OB_MESH, OB_CURVE, OB_SURF, OB_FONT)) {
+		if (ELEM(ob->type, OB_MESH, OB_CURVE, OB_SURF, OB_FONT, OB_MBALL)) {
 			EEVEE_materials_cache_populate(vedata, sldata, ob, &cast_shadow);
 		}
 		else if (ob->type == OB_LIGHTPROBE) {
diff --git a/source/blender/draw/engines/workbench/workbench_deferred.c b/source/blender/draw/engines/workbench/workbench_deferred.c
index b02c8ef3a4f..37978882abe 100644
--- a/source/blender/draw/engines/workbench/workbench_deferred.c
+++ b/source/blender/draw/engines/workbench/workbench_deferred.c
@@ -655,12 +655,12 @@ void workbench_deferred_solid_cache_populate(WORKBENCH_Data *vedata, Object *ob)
 	}
 
 	WORKBENCH_MaterialData *material;
-	if (ELEM(ob->type, OB_MESH, OB_CURVE, OB_SURF, OB_FONT)) {
+	if (ELEM(ob->type, OB_MESH, OB_CURVE, OB_SURF, OB_FONT, OB_MBALL)) {
 		const DRWContextState *draw_ctx = DRW_context_state_get();
 		const bool is_active = (ob == draw_ctx->obact);
 		const bool is_sculpt_mode = is_active && (draw_ctx->object_mode & OB_MODE_SCULPT) != 0;
 		bool is_drawn = false;
-		if (!is_sculpt_mode && wpd->drawtype == OB_TEXTURE && ob->type == OB_MESH) {
+		if (!is_sculpt_mode && wpd->drawtype == OB_TEXTURE && ELEM(ob->type, OB_MESH)) {
 			const Mesh *me = ob->data;
 			if (me->mloopuv) {
 				const int materials_len = MAX2(1, (is_sculpt_mode ? 1 : ob->totcol));
@@ -668,6 +668,10 @@ void workbench_deferred_solid_cache_populate(WORKBENCH_Data *vedata, Object *ob)
 				struct Gwn_Batch **geom_array = me->totcol ? DRW_cache_mesh_surface_texpaint_get(ob) : NULL;
 				if (materials_len > 0 && geom_array) {
 					for (int i = 0; i < materials_len; i++) {
+						if (geom_array[i] == NULL) {
+							continue;
+						}
+
 						Material *mat = give_current_material(ob, i + 1);
 						Image *image;
 						ED_object_get_active_image(ob, i + 1, &image, NULL, NULL, NULL);
@@ -710,6 +714,10 @@ void workbench_deferred_solid_cache_populate(WORKBENCH_Data *vedata, Object *ob)
 				        ob, gpumat_array, materials_len, NULL, NULL, NULL);
 				if (mat_geom) {
 					for (int i = 0; i < materials_len; ++i) {
+						if (mat_geom[i] == NULL) {
+							continue;
+						}
+
 						Material *mat = give_current_material(ob, i + 1);
 						material = get_or_create_material_data(vedata, ob, mat, NULL, OB_SOLID);
 						DRW_shgroup_call_object_add(material->shgrp, mat_geom[i], ob);
diff --git a/source/blender/draw/engines/workbench/workbench_forward.c b/source/blender/draw/engines/workbench/workbench_forward.c
index 2c2cde5ca20..1a387c8087c 100644
--- a/source/blender/draw/engines/workbench/workbench_forward.c
+++ b/source/blender/draw/engines/workbench/workbench_forward.c
@@ -461,14 +461,14 @@ void workbench_forward_cache_populate(WORKBENCH_Data *vedata, Object *ob)
 		return;
 	}
 
-	if (ELEM(ob->type, OB_MESH, OB_CURVE, OB_SURF, OB_FONT)) {
+	if (ELEM(ob->type, OB_MESH, OB_CURVE, OB_SURF, OB_FONT, OB_MBALL)) {
 		const DRWContextState *draw_ctx = DRW_context_state_get();
 		const bool is_active = (ob == draw_ctx->obact);
 		const bool is_sculpt_mode = is_active && (draw_ctx->object_mode & OB_MODE_SCULPT) != 0;
 		bool is_drawn = false;
 
 		WORKBENCH_MaterialData *material = get_or_create_material_data(vedata, ob, NULL, NULL, OB_SOLID);
-		if (!is_sculpt_mode && wpd->drawtype == OB_TEXTURE && ob->type == OB_MESH) {
+		if (!is_sculpt_mode && wpd->drawtype == OB_TEXTURE && ELEM(ob->type, OB_MESH)) {
 			const Mesh *me = ob->data;
 			if (me->mloopuv) {
 				const int materials_len = MAX2(1, (is_sculpt_mode ? 1 : ob->totcol));
@@ -476,6 +476,10 @@ void workbench_forward_cache_populate(WORKBENCH_Data *vedata, Object *ob)
 				struct Gwn_Batch **geom_array = me->totcol ? DRW_cache_mesh_surface_texpaint_get(ob) : NULL;
 				if (materials_len > 0 && geom_array) {
 					for (int i = 0; i < materials_len; i++) {
+						if(geom_array[i] == NULL) {
+							continue;
+						}
+
 						Material *mat = give_current_material(ob, i + 1);
 						Image *image;
 						ED_object_get_active_image(ob, i + 1, &image, NULL, NULL, NULL);
@@ -520,6 +524,10 @@ void workbench_forward_cache_populate(WORKBENCH_Data *vedata, Object *ob)
 				        ob, gpumat_array, materials_len, NULL, NULL, NULL);
 				if (mat_geom) {
 					for (int i = 0; i < materials_len; ++i) {
+						if(mat_geom[i] == NULL) {
+							continue;
+						}
+
 						Material *mat = give_current_material(ob, i + 1);
 						material = get_or_create_material_data(vedata, ob, mat, NULL, OB_SOLID);
 						DRW_shgroup_call_object_add(material->shgrp_object_outline, mat_geom[i], ob);