Draw manager: Initial implementation of key points visualization

Does all points all the time, ignoring the setting in viewport header.
This is to be addressed by the next commit.

4 files changed, 97 insertions, 9 deletions

diff --git a/source/blender/draw/intern/draw_cache.c b/source/blender/draw/intern/draw_cache.c
index 15f4aa319bd..95193bebaea 100644
--- a/source/blender/draw/intern/draw_cache.c
+++ b/source/blender/draw/intern/draw_cache.c
@@ -2886,11 +2886,16 @@ Gwn_Batch *DRW_cache_particles_get_dots(Object *object, ParticleSystem *psys)
 	return DRW_particles_batch_cache_get_dots(object, psys);
 }
 
-Gwn_Batch *DRW_cache_particles_get_edit_strands(struct PTCacheEdit* edit)
+Gwn_Batch *DRW_cache_particles_get_edit_strands(struct PTCacheEdit *edit)
 {
 	return DRW_particles_batch_cache_get_edit_strands(edit);
 }
 
+Gwn_Batch *DRW_cache_particles_get_edit_points(struct PTCacheEdit *edit)
+{
+	return DRW_particles_batch_cache_get_edit_points(edit);
+}
+
 Gwn_Batch *DRW_cache_particles_get_prim(int type)
 {
 	switch (type) {
diff --git a/source/blender/draw/intern/draw_cache.h b/source/blender/draw/intern/draw_cache.h
index 82cfe77d613..e726e25431f 100644
--- a/source/blender/draw/intern/draw_cache.h
+++ b/source/blender/draw/intern/draw_cache.h
@@ -169,7 +169,8 @@ struct Gwn_Batch *DRW_cache_lattice_vert_overlay_get(struct Object *ob);
 /* Particles */
 struct Gwn_Batch *DRW_cache_particles_get_hair(struct ParticleSystem *psys, struct ModifierData *md);
 struct Gwn_Batch *DRW_cache_particles_get_dots(struct Object *object, struct ParticleSystem *psys);
-struct Gwn_Batch *DRW_cache_particles_get_edit_strands(struct PTCacheEdit* edit);
+struct Gwn_Batch *DRW_cache_particles_get_edit_strands(struct PTCacheEdit *edit);
+struct Gwn_Batch *DRW_cache_particles_get_edit_points(struct PTCacheEdit *edit);
 struct Gwn_Batch *DRW_cache_particles_get_prim(int type);
 
 /* Metaball */
diff --git a/source/blender/draw/intern/draw_cache_impl.h b/source/blender/draw/intern/draw_cache_impl.h
index b537f1f0151..84c7825c6f9 100644
--- a/source/blender/draw/intern/draw_cache_impl.h
+++ b/source/blender/draw/intern/draw_cache_impl.h
@@ -125,6 +125,7 @@ void DRW_mesh_cache_sculpt_coords_ensure(struct Mesh *me);
 /* Particles */
 struct Gwn_Batch *DRW_particles_batch_cache_get_hair(struct ParticleSystem *psys, struct ModifierData *md);
 struct Gwn_Batch *DRW_particles_batch_cache_get_dots(struct Object *object, struct ParticleSystem *psys);
-struct Gwn_Batch *DRW_particles_batch_cache_get_edit_strands(struct PTCacheEdit* edit);
+struct Gwn_Batch *DRW_particles_batch_cache_get_edit_strands(struct PTCacheEdit *edit);
+struct Gwn_Batch *DRW_particles_batch_cache_get_edit_points(struct PTCacheEdit *edit);
 
 #endif /* __DRAW_CACHE_IMPL_H__ */
diff --git a/source/blender/draw/intern/draw_cache_impl_particles.c b/source/blender/draw/intern/draw_cache_impl_particles.c
index 0cc3c001ef2..065628f3f68 100644
--- a/source/blender/draw/intern/draw_cache_impl_particles.c
+++ b/source/blender/draw/intern/draw_cache_impl_particles.c
@@ -59,15 +59,22 @@ static void particle_batch_cache_clear(ParticleSystem *psys);
 /* Particle Gwn_Batch Cache */
 
 typedef struct ParticleBatchCache {
+	/* Object mode strands for hair and points for particle,
+	 * strands for paths when in edit mode.
+	 */
 	Gwn_VertBuf *pos;
 	Gwn_IndexBuf *indices;
-
 	Gwn_Batch *hairs;
 
 	int elems_count;
 	int point_count;
 
-	/* settings to determine if cache is invalid */
+	/* Control points when in edit mode. */
+	Gwn_VertBuf *edit_pos;
+	Gwn_Batch *edit_points;
+	int edit_point_count;
+
+	/* Settings to determine if cache is invalid. */
 	bool is_dirty;
 } ParticleBatchCache;
 
@@ -143,9 +150,11 @@ static void particle_batch_cache_clear(ParticleSystem *psys)
 	}
 
 	GWN_BATCH_DISCARD_SAFE(cache->hairs);
-
 	GWN_VERTBUF_DISCARD_SAFE(cache->pos);
 	GWN_INDEXBUF_DISCARD_SAFE(cache->indices);
+
+	GWN_BATCH_DISCARD_SAFE(cache->edit_points);
+	GWN_VERTBUF_DISCARD_SAFE(cache->edit_pos);
 }
 
 void DRW_particle_batch_cache_free(ParticleSystem *psys)
@@ -173,7 +182,7 @@ static void ensure_seg_pt_count(ParticleSystem *psys, ParticleBatchCache *cache)
 		cache->elems_count = 0;
 		cache->point_count = 0;
 
-		PTCacheEdit* edit = PE_get_current_from_psys(psys);
+		PTCacheEdit *edit = PE_get_current_from_psys(psys);
 		if (edit != NULL && edit->pathcache != NULL) {
 			count_cache_segment_keys(edit->pathcache, psys->totpart, cache);
 		} else {
@@ -436,7 +445,7 @@ static void particle_batch_cache_ensure_pos_and_seg(ParticleSystem *psys,
 		}
 	}
 
-	PTCacheEdit* edit = PE_get_current_from_psys(psys);
+	PTCacheEdit *edit = PE_get_current_from_psys(psys);
 	if (edit != NULL && edit->pathcache != NULL) {
 		curr_point = particle_batch_cache_fill_segments(
 		        psys, psmd, edit->pathcache, PARTICLE_SOURCE_PARENT,
@@ -578,7 +587,7 @@ Gwn_Batch *DRW_particles_batch_cache_get_dots(Object *object, ParticleSystem *ps
 	return cache->hairs;
 }
 
-Gwn_Batch *DRW_particles_batch_cache_get_edit_strands(PTCacheEdit* edit)
+Gwn_Batch *DRW_particles_batch_cache_get_edit_strands(PTCacheEdit *edit)
 {
 	ParticleSystem *psys = edit->psys;
 	ParticleBatchCache *cache = particle_batch_cache_get(psys);
@@ -590,3 +599,75 @@ Gwn_Batch *DRW_particles_batch_cache_get_edit_strands(PTCacheEdit* edit)
 	cache->hairs = GWN_batch_create(GWN_PRIM_LINE_STRIP, cache->pos, cache->indices);
 	return cache->hairs;
 }
+
+static void ensure_edit_points_count(const PTCacheEdit *edit,
+                                     ParticleBatchCache *cache)
+{
+	if (cache->edit_pos != NULL) {
+		return;
+	}
+	cache->edit_point_count = 0;
+	for (int point_index = 0; point_index < edit->totpoint; point_index++) {
+		const PTCacheEditPoint *point = &edit->points[point_index];
+		cache->edit_point_count += point->totkey;
+	}
+}
+
+static void particle_batch_cache_ensure_edit_pos(PTCacheEdit *edit,
+                                                 ParticleBatchCache *cache)
+{
+	if (cache->edit_pos != NULL) {
+		return;
+	}
+
+	static Gwn_VertFormat format = { 0 };
+	static unsigned pos_id, color_id;
+
+	GWN_VERTBUF_DISCARD_SAFE(cache->edit_pos);
+
+	if (format.attrib_ct == 0) {
+		/* initialize vertex format */
+		pos_id = GWN_vertformat_attr_add(&format, "pos", GWN_COMP_F32, 3, GWN_FETCH_FLOAT);
+		color_id = GWN_vertformat_attr_add(&format, "color", GWN_COMP_F32, 4, GWN_FETCH_FLOAT);
+	}
+
+	cache->edit_pos = GWN_vertbuf_create_with_format(&format);
+	GWN_vertbuf_data_alloc(cache->edit_pos, cache->edit_point_count);
+
+	/* Convert theme colors from uchar[3] to float[4]. */
+	float selected_color[4] = {0.0f, 0.0f, 0.0f, 1.0f};
+	float normal_color[4] = {0.0f, 0.0f, 0.0f, 1.0f};
+	rgb_uchar_to_float(selected_color, edit->sel_col);
+	rgb_uchar_to_float(normal_color, edit->nosel_col);
+
+	int global_key_index = 0;
+	for (int point_index = 0; point_index < edit->totpoint; point_index++) {
+		const PTCacheEditPoint *point = &edit->points[point_index];
+		for (int key_index = 0; key_index < point->totkey; key_index++) {
+			PTCacheEditKey *key = &point->keys[key_index];
+			GWN_vertbuf_attr_set(cache->edit_pos, pos_id, global_key_index, key->world_co);
+			if (key->flag & PEK_SELECT) {
+				GWN_vertbuf_attr_set(cache->edit_pos, color_id, global_key_index, selected_color);
+			}
+			else {
+				GWN_vertbuf_attr_set(cache->edit_pos, color_id, global_key_index, normal_color);
+			}
+			global_key_index++;
+		}
+	}
+}
+
+Gwn_Batch *DRW_particles_batch_cache_get_edit_points(PTCacheEdit *edit)
+{
+	ParticleSystem *psys = edit->psys;
+	ParticleBatchCache *cache = particle_batch_cache_get(psys);
+	if (cache->edit_points != NULL) {
+		return cache->edit_points;
+	}
+	ensure_edit_points_count(edit, cache);
+	particle_batch_cache_ensure_edit_pos(edit, cache);
+	cache->edit_points = GWN_batch_create(GWN_PRIM_POINTS,
+	                                      cache->edit_pos,
+	                                      NULL);
+	return cache->edit_points;
+}