Workbench: StudioLight HDRI's

The Studio lights are now loaded from disk. The location is
`datafiles/studiolights` they need to be JPG for now. JPG cannot store
HDRI color range but they are clamped inside the Workbench
engine for speed reason. I didn't select JP2K as it might not be
enabled.

Users can add upto 20 HDRI files. This limitation is inside the
RNA_space.c Currently the icons are calculated when you first open the
selection box for the HDRI's. We could add them to a background
rendering later.

I added 2 test files a sky texture rendered in Cycles and an HDRI from
cloud.blender.org.

17 files changed, 496 insertions, 150 deletions

diff --git a/release/datafiles/studiolights/sl01.jpg b/release/datafiles/studiolights/sl01.jpg
new file mode 100644
index 00000000000..cd007bade68
--- /dev/null
+++ b/release/datafiles/studiolights/sl01.jpg
diff --git a/release/datafiles/studiolights/sl02.jpg b/release/datafiles/studiolights/sl02.jpg
new file mode 100644
index 00000000000..1c9ce99a0d8
--- /dev/null
+++ b/release/datafiles/studiolights/sl02.jpg
diff --git a/source/blender/blenkernel/BKE_icons.h b/source/blender/blenkernel/BKE_icons.h
index 766704b8f9c..e54531bdb0e 100644
--- a/source/blender/blenkernel/BKE_icons.h
+++ b/source/blender/blenkernel/BKE_icons.h
@@ -43,6 +43,7 @@ enum {
 	ICON_DATA_PREVIEW,
 	/** 2D triangles: obj is #Icon_Geom */
 	ICON_DATA_GEOM,
+	ICON_DATA_STUDIOLIGHT,
 };
 
 struct Icon {
@@ -77,6 +78,7 @@ typedef struct Icon Icon;
 struct ImBuf;
 struct PreviewImage;
 struct ID;
+struct StudioLight;
 
 enum eIconSizes;
 
@@ -158,6 +160,8 @@ struct ImBuf *BKE_icon_geom_rasterize(
         const struct Icon_Geom *geom,
         const unsigned int size_x, const unsigned int size_y);
 
+int BKE_icon_ensure_studio_light(struct StudioLight *sl);
+
 #define ICON_RENDER_DEFAULT_HEIGHT 32
 
 #endif /*  __BKE_ICONS_H__ */
diff --git a/source/blender/blenkernel/BKE_studiolight.h b/source/blender/blenkernel/BKE_studiolight.h
new file mode 100644
index 00000000000..c65e9050157
--- /dev/null
+++ b/source/blender/blenkernel/BKE_studiolight.h
@@ -0,0 +1,73 @@
+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2006-2007 Blender Foundation.
+ * All rights reserved.
+ *
+ * The Original Code is: all of this file.
+ *
+ * Contributor(s): none yet.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+#ifndef __BKE_STUDIOLIGHT_H__
+#define __BKE_STUDIOLIGHT_H__
+
+/** \file BKE_studiolight.h
+ *  \ingroup bke
+ *
+ * Studio lighting for the 3dview
+ */
+
+#include "BLI_sys_types.h"
+
+#include "DNA_space_types.h"
+
+#define STUDIOLIGHT_X_POS 0
+#define STUDIOLIGHT_X_NEG 1
+#define STUDIOLIGHT_Y_POS 2
+#define STUDIOLIGHT_Y_NEG 3
+#define STUDIOLIGHT_Z_POS 4
+#define STUDIOLIGHT_Z_NEG 5
+
+enum StudioLightFlag
+{
+	STUDIOLIGHT_DIFFUSE_LIGHT_CALCULATED = (1 << 0),
+	STUDIOLIGHT_EXTERNAL_FILE            = (1 << 1),
+} StudioLightFlag;
+
+typedef struct StudioLight
+{
+	struct StudioLight *next, *prev;
+	int flag;
+	char name[FILE_MAXFILE];
+	char path[FILE_MAX];
+	int icon_id;
+	int index;
+	float diffuse_light[6][3];
+} StudioLight;
+
+void BKE_studiolight_init(void);
+void BKE_studiolight_free(void);
+struct StudioLight *BKE_studiolight_find(const char* name);
+struct StudioLight *BKE_studiolight_findindex(int index);
+unsigned int *BKE_studiolight_preview(StudioLight *sl, int icon_size);
+const struct ListBase *BKE_studiolight_listbase(void);
+void BKE_studiolight_ensure_flag(StudioLight *sl, int flag);
+
+#endif /*  __BKE_STUDIOLIGHT_H__ */
diff --git a/source/blender/blenkernel/CMakeLists.txt b/source/blender/blenkernel/CMakeLists.txt
index 37e08cedb10..d5ce6f2f94d 100644
--- a/source/blender/blenkernel/CMakeLists.txt
+++ b/source/blender/blenkernel/CMakeLists.txt
@@ -185,6 +185,7 @@ set(SRC
 	intern/softbody.c
 	intern/sound.c
 	intern/speaker.c
+	intern/studiolight.c
 	intern/subsurf_ccg.c
 	intern/suggestions.c
 	intern/text.c
@@ -303,6 +304,7 @@ set(SRC
 	BKE_softbody.h
 	BKE_sound.h
 	BKE_speaker.h
+	BKE_studiolight.h
 	BKE_subsurf.h
 	BKE_suggestions.h
 	BKE_text.h
diff --git a/source/blender/blenkernel/intern/icons.c b/source/blender/blenkernel/intern/icons.c
index f1f343faac8..61c05c2500d 100644
--- a/source/blender/blenkernel/intern/icons.c
+++ b/source/blender/blenkernel/intern/icons.c
@@ -56,6 +56,7 @@
 
 #include "BKE_icons.h"
 #include "BKE_global.h" /* only for G.background test */
+#include "BKE_studiolight.h"
 
 #include "BLI_sys_types.h" // for intptr_t support
 
@@ -802,3 +803,13 @@ struct Icon_Geom *BKE_icon_geom_from_file(const char *filename)
 }
 
 /** \} */
+
+/** \name Studio Light Icon
+ * \{ */
+int BKE_icon_ensure_studio_light(struct StudioLight *sl) {
+	int icon_id = get_next_free_id();
+	icon_create(icon_id, ICON_DATA_STUDIOLIGHT, sl);
+	return icon_id;
+}
+/** \} */
+
diff --git a/source/blender/blenkernel/intern/studiolight.c b/source/blender/blenkernel/intern/studiolight.c
new file mode 100644
index 00000000000..9bc678a1820
--- /dev/null
+++ b/source/blender/blenkernel/intern/studiolight.c
@@ -0,0 +1,297 @@
+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2006-2007 Blender Foundation.
+ * All rights reserved.
+ *
+ * The Original Code is: all of this file.
+ *
+ * Contributor(s): none yet.
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ *
+ */
+
+/** \file blender/blenkernel/intern/studiolight.c
+ *  \ingroup bke
+ */
+
+#include "BKE_studiolight.h"
+
+#include "BKE_appdir.h"
+#include "BKE_icons.h"
+
+#include "BLI_fileops.h"
+#include "BLI_fileops_types.h"
+#include "BLI_listbase.h"
+#include "BLI_math.h"
+#include "BLI_path_util.h"
+#include "BLI_string.h"
+
+#include "DNA_listBase.h"
+
+#include "IMB_imbuf.h"
+#include "IMB_imbuf_types.h"
+
+#include "MEM_guardedalloc.h"
+
+
+/* Statics */
+static ListBase studiolights;
+static const char *STUDIO_LIGHT_FOLDER = "studiolights/";
+
+/* FUNCTIONS */
+static void studiolight_free(struct StudioLight *sl)
+{
+	MEM_freeN(sl);
+}
+
+static struct StudioLight *studiolight_create(void)
+{
+	struct StudioLight *sl = MEM_callocN(sizeof(*sl), __func__);
+	sl->path[0] = 0x00;
+	sl->name[0] = 0x00;
+	sl->flag = 0;
+	sl->index = BLI_listbase_count(&studiolights);
+	sl->icon_id = BKE_icon_ensure_studio_light(sl);
+	return sl;
+}
+
+static void direction_to_equirectangular(float r[2], const float dir[3])
+{
+	r[0] = (atan2f(dir[1], dir[0]) - M_PI) / -(M_PI * 2);
+	r[1] = (acosf(dir[2] / 1.0) - M_PI) / -M_PI;
+}
+
+static void studiolight_calculate_directional_diffuse_light(ImBuf *ibuf, float color[4], const float start[3], const float v1[3], const float v2[3], int steps)
+{
+	float uv[2];
+	float dir[3];
+	float col[4];
+	float v11[3];
+	float v12[3];
+	float totcol[4];
+
+	zero_v4(totcol);
+	for (int x = 0; x < steps ; x++) {
+		float xf = (float)x / (float)steps;
+		mul_v3_v3fl(v11, v1, xf);
+		for (int y = 0; y < steps; y++) {
+			float yf = (float)y / (float)steps;
+			/* start + x/steps*v1 + y/steps*v2 */
+			mul_v3_v3fl(v12, v2, yf);
+			add_v3_v3v3(dir, start, v11);
+			add_v3_v3(dir, v12);
+			/* normalize */
+			normalize_v3(dir);
+
+			/* sample */
+			direction_to_equirectangular(uv, dir);
+			nearest_interpolation_color_wrap(ibuf, NULL, col, uv[0] * ibuf->x, uv[1] * ibuf->y);
+			add_v3_v3(totcol, col);
+		}
+	}
+	mul_v3_v3fl(color, totcol, 1.0/(steps*steps));
+}
+
+static void studiolight_calculate_diffuse_light(StudioLight *sl)
+{
+	const int steps = 16;
+	float start[3];
+	float v1[3];
+	float v2[3];
+
+	/* init light to black */
+	copy_v3_fl(sl->diffuse_light[STUDIOLIGHT_X_POS], 0.0f);
+	copy_v3_fl(sl->diffuse_light[STUDIOLIGHT_X_NEG], 0.0f);
+	copy_v3_fl(sl->diffuse_light[STUDIOLIGHT_Y_POS], 0.0f);
+	copy_v3_fl(sl->diffuse_light[STUDIOLIGHT_Y_NEG], 0.0f);
+	copy_v3_fl(sl->diffuse_light[STUDIOLIGHT_Z_POS], 0.0f);
+	copy_v3_fl(sl->diffuse_light[STUDIOLIGHT_Z_NEG], 0.0f);
+
+	if (sl->flag &= STUDIOLIGHT_EXTERNAL_FILE) {
+		ImBuf* ibuf = NULL;
+		ibuf = IMB_loadiffname(sl->path, 0, NULL);
+		if (ibuf) {
+			IMB_float_from_rect(ibuf);
+
+			copy_v3_fl3(start, -1.0f, -1.0f, -1.0f);
+			copy_v3_fl3(v1, 0.0f, 2.0f, 0.0f);
+			copy_v3_fl3(v2, 0.0f, 0.0f, 2.0f);
+			studiolight_calculate_directional_diffuse_light(ibuf, sl->diffuse_light[STUDIOLIGHT_Z_NEG], start, v1, v2, steps);
+			copy_v3_fl3(start, 1.0f, -1.0f, -1.0f);
+			studiolight_calculate_directional_diffuse_light(ibuf, sl->diffuse_light[STUDIOLIGHT_Z_POS], start, v1, v2, steps);
+
+			copy_v3_fl3(start, -1.0f, -1.0f, -1.0f);
+			copy_v3_fl3(v1, 2.0f, 0.0f, 0.0f);
+			copy_v3_fl3(v2, 0.0f, 0.0f, 2.0f);
+			studiolight_calculate_directional_diffuse_light(ibuf, sl->diffuse_light[STUDIOLIGHT_X_POS], start, v1, v2, steps);
+			copy_v3_fl3(start, -1.0f, 1.0f, -1.0f);
+			studiolight_calculate_directional_diffuse_light(ibuf, sl->diffuse_light[STUDIOLIGHT_X_NEG], start, v1, v2, steps);
+
+			copy_v3_fl3(start, -1.0f, -1.0f, -1.0f);
+			copy_v3_fl3(v1, 2.0f, 0.0f, 0.0f);
+			copy_v3_fl3(v2, 0.0f, 2.0f, 0.0f);
+			studiolight_calculate_directional_diffuse_light(ibuf, sl->diffuse_light[STUDIOLIGHT_Y_NEG], start, v1, v2, steps);
+			copy_v3_fl3(start, -1.0f, -1.0f, 1.0f);
+			studiolight_calculate_directional_diffuse_light(ibuf, sl->diffuse_light[STUDIOLIGHT_Y_POS], start, v1, v2, steps);
+
+			IMB_freeImBuf(ibuf);
+		}
+	}
+	sl->flag |= STUDIOLIGHT_DIFFUSE_LIGHT_CALCULATED;
+}
+
+
+/* API */
+void BKE_studiolight_init(void)
+{
+	StudioLight *sl;
+	/* go over the preset folder and add a studiolight for every image with its path */
+	/* order studio lights by name */
+	/* Also reserve icon space for it. */
+	/* Add default studio light */
+	sl = studiolight_create();
+	BLI_strncpy(sl->name, "INTERNAL_01\0", FILE_MAXFILE);
+	sl->flag = STUDIOLIGHT_DIFFUSE_LIGHT_CALCULATED;
+	copy_v3_fl(sl->diffuse_light[STUDIOLIGHT_X_POS], 0.0f);
+	copy_v3_fl(sl->diffuse_light[STUDIOLIGHT_X_NEG], 0.0f);
+	copy_v3_fl(sl->diffuse_light[STUDIOLIGHT_Y_POS], 0.0f);
+	copy_v3_fl(sl->diffuse_light[STUDIOLIGHT_Y_NEG], 0.0f);
+	copy_v3_fl(sl->diffuse_light[STUDIOLIGHT_Z_POS], 1.0f);
+	copy_v3_fl(sl->diffuse_light[STUDIOLIGHT_Z_NEG], 0.0f);
+	BLI_addtail(&studiolights, sl);
+
+	struct direntry *dir;
+	const char *folder = BKE_appdir_folder_id(BLENDER_DATAFILES, STUDIO_LIGHT_FOLDER);
+	unsigned int totfile = BLI_filelist_dir_contents(folder, &dir);
+	int i;
+	for (i = 0; i < totfile; i++) {
+		if ((dir[i].type & S_IFREG)) {
+			const char *filename = dir[i].relname;
+			const char *path = dir[i].path;
+			if (BLI_testextensie(filename, ".jpg")) {
+				sl = studiolight_create();
+				sl->flag = STUDIOLIGHT_EXTERNAL_FILE;
+				BLI_strncpy(sl->name, filename, FILE_MAXFILE);
+				BLI_strncpy(sl->path, path, FILE_MAXFILE);
+				BLI_addtail(&studiolights, sl);
+			}
+		}
+	}
+	BLI_filelist_free(dir, totfile);
+	dir = NULL;
+}
+
+void BKE_studiolight_free(void)
+{
+	struct StudioLight *sl;
+	while((sl = (StudioLight*)BLI_pophead(&studiolights)))
+	{
+		studiolight_free(sl);
+	}
+}
+
+struct StudioLight *BKE_studiolight_find(const char* name)
+{
+	LISTBASE_FOREACH(StudioLight *, sl, &studiolights) {
+		if (STREQLEN(sl->name, name, FILE_MAXFILE)) {
+			return sl;
+		}
+	}
+	/* When not found, use the default studio light */
+	return (StudioLight*)studiolights.first;
+}
+
+struct StudioLight *BKE_studiolight_findindex(int index)
+{
+	LISTBASE_FOREACH(StudioLight *, sl, &studiolights) {
+		if (sl->index == index) {
+			return sl;
+		}
+	}
+	/* When not found, use the default studio light */
+	return (StudioLight*)studiolights.first;
+}
+
+const struct ListBase *BKE_studiolight_listbase(void)
+{
+	return &studiolights;
+}
+
+unsigned int *BKE_studiolight_preview(StudioLight *sl, int icon_size)
+{
+	BKE_studiolight_ensure_flag(sl, STUDIOLIGHT_DIFFUSE_LIGHT_CALCULATED);
+
+	uint *rect = MEM_mallocN(icon_size * icon_size * sizeof(uint), __func__);
+	int icon_center = icon_size / 2;
+	float sphere_radius = icon_center * 0.9;
+
+	int offset = 0;
+	for (int y = 0; y < icon_size; y++) {
+		float dy = y - icon_center;
+		for (int x = 0; x < icon_size; x++) {
+			float dx = x - icon_center;
+			/* calculate aliasing */
+			float alias = 0;
+			const float alias_step = 0.333;
+			for (float ay = dy - 0.5; ay < dy + 0.5; ay += alias_step) {
+				for (float ax = dx - 0.5; ax < dx + 0.5; ax += alias_step) {
+					if (sqrt(ay * ay + ax * ax) < sphere_radius) {
+						alias += alias_step * alias_step;
+					}
+				}
+			}
+			uint pixelresult = 0x0;
+			uint alias_i = clamp_i(alias * 256, 0, 255);
+			if (alias_i != 0) {
+				/* calculate normal */
+				uint alias_mask = alias_i << 24;
+				float normal[3];
+				normal[0] = dx / sphere_radius;
+				normal[1] = dy / sphere_radius;
+				normal[2] = sqrt(-(normal[0] * normal[0]) - (normal[1] * normal[1]) + 1);
+				normalize_v3(normal);
+
+				float color[3];
+				mul_v3_v3fl(color, sl->diffuse_light[STUDIOLIGHT_X_POS], clamp_f(normal[0], 0.0, 1.0));
+				interp_v3_v3v3(color, color, sl->diffuse_light[STUDIOLIGHT_X_NEG], clamp_f(-normal[0], 0.0, 1.0));
+				interp_v3_v3v3(color, color, sl->diffuse_light[STUDIOLIGHT_Y_POS], clamp_f(normal[1], 0.0, 1.0));
+				interp_v3_v3v3(color, color, sl->diffuse_light[STUDIOLIGHT_Y_NEG], clamp_f(-normal[1], 0.0, 1.0));
+				interp_v3_v3v3(color, color, sl->diffuse_light[STUDIOLIGHT_Z_POS], clamp_f(normal[2], 0.0, 1.0));
+
+				pixelresult = rgb_to_cpack(
+				        linearrgb_to_srgb(color[0]),
+				        linearrgb_to_srgb(color[1]),
+				        linearrgb_to_srgb(color[2])) | alias_mask;
+			}
+			rect[offset++] = pixelresult;
+		}
+	}
+	return rect;
+}
+
+void BKE_studiolight_ensure_flag(StudioLight *sl, int flag)
+{
+	if (sl->flag & flag){
+		return;
+	}
+
+	if ((flag & STUDIOLIGHT_DIFFUSE_LIGHT_CALCULATED)) {
+		studiolight_calculate_diffuse_light(sl);
+	}
+}
diff --git a/source/blender/draw/DRW_engine.h b/source/blender/draw/DRW_engine.h
index a1a2a36e75a..524a94e5886 100644
--- a/source/blender/draw/DRW_engine.h
+++ b/source/blender/draw/DRW_engine.h
@@ -135,5 +135,4 @@ void DRW_opengl_context_disable(void);
 
 void DRW_deferred_shader_remove(struct GPUMaterial *mat);
 
-uint *WORKBENCH_generate_studiolight_preview(int studiolight_id, int icon_size);
 #endif /* __DRW_ENGINE_H__ */
diff --git a/source/blender/draw/engines/workbench/workbench_materials.c b/source/blender/draw/engines/workbench/workbench_materials.c
index 0fee42619c3..680ac264233 100644
--- a/source/blender/draw/engines/workbench/workbench_materials.c
+++ b/source/blender/draw/engines/workbench/workbench_materials.c
@@ -338,6 +338,7 @@ void workbench_materials_cache_init(WORKBENCH_Data *vedata)
 	if (v3d) {
 		wpd->shading = v3d->shading;
 		wpd->drawtype = v3d->drawtype;
+		wpd->studio_light = BKE_studiolight_find(wpd->shading.studio_light);
 	}
 	else {
 		/* XXX: We should get the default shading from the view layer, after we implemented the render callback */
@@ -346,7 +347,9 @@ void workbench_materials_cache_init(WORKBENCH_Data *vedata)
 		wpd->shading.shadow_intensity = 0.5;
 		copy_v3_fl(wpd->shading.single_color, 0.8f);
 		wpd->drawtype = OB_SOLID;
+		wpd->studio_light = BKE_studiolight_findindex(0);
 	}
+	BKE_studiolight_ensure_flag(wpd->studio_light, STUDIOLIGHT_DIFFUSE_LIGHT_CALCULATED);
 
 	select_deferred_shaders(wpd);
 	/* Deferred Mix Pass */
@@ -360,7 +363,7 @@ void workbench_materials_cache_init(WORKBENCH_Data *vedata)
 		srgb_to_linearrgb_v3_v3(wd->background_color_high, wd->background_color_high);
 		srgb_to_linearrgb_v3_v3(wd->background_color_low, wd->background_color_low);
 
-		studiolight_update_world(wpd->shading.studio_light, wd);
+		studiolight_update_world(wpd->studio_light, wd);
 
 		wpd->world_ubo = DRW_uniformbuffer_create(sizeof(WORKBENCH_UBO_World), NULL);
 		DRW_uniformbuffer_update(wpd->world_ubo, &wpd->world_data);
diff --git a/source/blender/draw/engines/workbench/workbench_private.h b/source/blender/draw/engines/workbench/workbench_private.h
index 7a646d056b5..dde62302f62 100644
--- a/source/blender/draw/engines/workbench/workbench_private.h
+++ b/source/blender/draw/engines/workbench/workbench_private.h
@@ -27,6 +27,8 @@
 #define __WORKBENCH_PRIVATE_H__
 
 
+#include "BKE_studiolight.h"
+
 #include "DNA_image_types.h"
 #include "DNA_view3d_types.h"
 
@@ -81,6 +83,7 @@ typedef struct WORKBENCH_PrivateData {
 	struct GPUShader *prepass_texture_sh;
 	struct GPUShader *composite_sh;
 	View3DShading shading;
+	StudioLight *studio_light;
 	int drawtype;
 	struct GPUUniformBuffer *world_ubo;
 	struct DRWShadingGroup *shadow_shgrp;
@@ -127,6 +130,6 @@ void workbench_materials_solid_cache_populate(WORKBENCH_Data *vedata, Object *ob
 void workbench_materials_cache_finish(WORKBENCH_Data *vedata);
 
 /* workbench_studiolight.c */
-void studiolight_update_world(int studio_light, WORKBENCH_UBO_World *wd);
+void studiolight_update_world(StudioLight *sl, WORKBENCH_UBO_World *wd);
 
 #endif
diff --git a/source/blender/draw/engines/workbench/workbench_studiolight.c b/source/blender/draw/engines/workbench/workbench_studiolight.c
index 5b1d4432ca7..f7d107ea403 100644
--- a/source/blender/draw/engines/workbench/workbench_studiolight.c
+++ b/source/blender/draw/engines/workbench/workbench_studiolight.c
@@ -22,118 +22,19 @@
 /** \file workbench_studiolight.c
  *  \ingroup draw_engine
  */
+#include "BKE_studiolight.h"
+
 #include "DRW_engine.h"
 #include "workbench_private.h"
 
 #include "BLI_math.h"
 
-
-#define STUDIOLIGHT_X_POS 0
-#define STUDIOLIGHT_X_NEG 1
-#define STUDIOLIGHT_Y_POS 2
-#define STUDIOLIGHT_Y_NEG 3
-#define STUDIOLIGHT_Z_POS 4
-#define STUDIOLIGHT_Z_NEG 5
-
-const float studiolights[][6][3] = {
-	{
-		{1.0,  0.8,   0.6},
-		{1.0,  0.6,   0.6},
-		{0.9,  0.9,   1.0},
-		{0.05, 0.025, 0.025},
-		{0.8,  0.8,   0.75},
-		{1.0,  0.95,  0.8},
-	},
-	{
-		{0.0, 0.0, 0.0},
-		{0.0, 0.0, 0.0},
-		{0.0, 0.0, 0.0},
-		{0.0, 0.0, 0.0},
-		{0.8, 0.8, 1.0},
-		{0.0, 0.0, 0.0},
-	},
-	{
-		{0.4, 0.3, 0.8},
-		{0.4, 0.3, 0.8},
-		{0.8, 0.8, 0.2},
-		{0.0, 0.0, 0.0},
-		{0.4, 0.4, 0.8},
-		{0.0, 0.0, 0.0},
-	},
-	{
-		{0.2, 0.2, 0.0},
-		{0.8, 0.2, 0.0},
-		{0.8, 0.2, 0.0},
-		{0.2, 0.2, 0.0},
-		{0.8, 0.6, 0.4},
-		{0.0, 0.0, 0.0},
-	},
-	{
-		{0.8, 0.2, 0.0},
-		{0.8, 0.2, 0.0},
-		{0.8, 0.6, 0.0},
-		{0.2, 0.2, 0.0},
-		{1.0, 0.5, 0.0},
-		{0.0, 0.0, 0.0},
-	},
-};
-
-void studiolight_update_world(int studio_light, WORKBENCH_UBO_World *wd)
-{
-	copy_v3_v3(wd->diffuse_light_x_pos, studiolights[studio_light][STUDIOLIGHT_X_POS]);
-	copy_v3_v3(wd->diffuse_light_x_neg, studiolights[studio_light][STUDIOLIGHT_X_NEG]);
-	copy_v3_v3(wd->diffuse_light_y_pos, studiolights[studio_light][STUDIOLIGHT_Y_POS]);
-	copy_v3_v3(wd->diffuse_light_y_neg, studiolights[studio_light][STUDIOLIGHT_Y_NEG]);
-	copy_v3_v3(wd->diffuse_light_z_pos, studiolights[studio_light][STUDIOLIGHT_Z_POS]);
-	copy_v3_v3(wd->diffuse_light_z_neg, studiolights[studio_light][STUDIOLIGHT_Z_NEG]);
-}
-
-uint *WORKBENCH_generate_studiolight_preview(int studiolight_id, int icon_size)
+void studiolight_update_world(StudioLight *sl, WORKBENCH_UBO_World *wd)
 {
-	uint *rect = MEM_mallocN(icon_size * icon_size * sizeof(uint), __func__);
-	int icon_center = icon_size / 2;
-	float sphere_radius = icon_center * 0.9;
-
-	int offset = 0;
-	for (int y = 0; y < icon_size; y++) {
-		float dy = y - icon_center;
-		for (int x = 0; x < icon_size; x++) {
-			float dx = x - icon_center;
-			/* calculate aliasing */
-			float alias = 0;
-			const float alias_step = 0.2;
-			for (float ay = dy - 0.5; ay < dy + 0.5; ay += alias_step) {
-				for (float ax = dx - 0.5; ax < dx + 0.5; ax += alias_step) {
-					if (sqrt(ay * ay + ax * ax) < sphere_radius) {
-						alias += alias_step * alias_step;
-					}
-				}
-			}
-			uint pixelresult = 0x0;
-			uint alias_i = clamp_i(alias * 256, 0, 255);
-			if (alias_i != 0) {
-				/* calculate normal */
-				uint alias_mask = alias_i << 24;
-				float normal[3];
-				normal[0] = dx / sphere_radius;
-				normal[1] = dy / sphere_radius;
-				normal[2] = sqrt(-(normal[0] * normal[0]) - (normal[1] * normal[1]) + 1);
-				normalize_v3(normal);
-
-				float color[3];
-				mul_v3_v3fl(color, studiolights[studiolight_id][STUDIOLIGHT_X_POS], clamp_f(normal[0], 0.0, 1.0));
-				interp_v3_v3v3(color, color, studiolights[studiolight_id][STUDIOLIGHT_X_NEG], clamp_f(-normal[0], 0.0, 1.0));
-				interp_v3_v3v3(color, color, studiolights[studiolight_id][STUDIOLIGHT_Y_POS], clamp_f(normal[1], 0.0, 1.0));
-				interp_v3_v3v3(color, color, studiolights[studiolight_id][STUDIOLIGHT_Y_NEG], clamp_f(-normal[1], 0.0, 1.0));
-				interp_v3_v3v3(color, color, studiolights[studiolight_id][STUDIOLIGHT_Z_POS], clamp_f(normal[2], 0.0, 1.0));
-
-				pixelresult = rgb_to_cpack(
-				        linearrgb_to_srgb(color[0]),
-				        linearrgb_to_srgb(color[1]),
-				        linearrgb_to_srgb(color[2])) | alias_mask;
-			}
-			rect[offset++] = pixelresult;
-		}
-	}
-	return rect;
+	copy_v3_v3(wd->diffuse_light_x_pos, sl->diffuse_light[STUDIOLIGHT_X_POS]);
+	copy_v3_v3(wd->diffuse_light_x_neg, sl->diffuse_light[STUDIOLIGHT_X_NEG]);
+	copy_v3_v3(wd->diffuse_light_y_pos, sl->diffuse_light[STUDIOLIGHT_Y_POS]);
+	copy_v3_v3(wd->diffuse_light_y_neg, sl->diffuse_light[STUDIOLIGHT_Y_NEG]);
+	copy_v3_v3(wd->diffuse_light_z_pos, sl->diffuse_light[STUDIOLIGHT_Z_POS]);
+	copy_v3_v3(wd->diffuse_light_z_neg, sl->diffuse_light[STUDIOLIGHT_Z_NEG]);
 }
diff --git a/source/blender/editors/include/UI_icons.h b/source/blender/editors/include/UI_icons.h
index b0ee6773e7a..6a9067ef95d 100644
--- a/source/blender/editors/include/UI_icons.h
+++ b/source/blender/editors/include/UI_icons.h
@@ -1031,10 +1031,3 @@ DEF_VICO(COLORSET_17_VEC)
 DEF_VICO(COLORSET_18_VEC)
 DEF_VICO(COLORSET_19_VEC)
 DEF_VICO(COLORSET_20_VEC)
-
-	/* Studio lighting presets */
-DEF_ICON(STUDIOLIGHT_01)
-DEF_ICON(STUDIOLIGHT_02)
-DEF_ICON(STUDIOLIGHT_03)
-DEF_ICON(STUDIOLIGHT_04)
-DEF_ICON(STUDIOLIGHT_05)
diff --git a/source/blender/editors/interface/interface_icons.c b/source/blender/editors/interface/interface_icons.c
index afd57fdcd05..9f5c2005878 100644
--- a/source/blender/editors/interface/interface_icons.c
+++ b/source/blender/editors/interface/interface_icons.c
@@ -58,6 +58,7 @@
 #include "BKE_global.h"
 #include "BKE_icons.h"
 #include "BKE_appdir.h"
+#include "BKE_studiolight.h"
 
 #include "IMB_imbuf.h"
 #include "IMB_imbuf_types.h"
@@ -493,23 +494,6 @@ static void init_matcap_icons(void)
 
 }
 
-static void init_studio_light_icons(void)
-{
-	/* dynamic allocation now, tucking datatoc pointers in DrawInfo */
-#define INIT_STUDIOLIGHT_ICON(icon_id, studiolight_id)                                         \
-	{                                                                                          \
-		DrawInfo *di;                                                                          \
-		di = def_internal_icon(NULL, icon_id, 0, 0, 96, ICON_TYPE_BUFFER);                     \
-		di->data.buffer.image->rect = WORKBENCH_generate_studiolight_preview(studiolight_id, 96); \
-	} (void)0
-
-	INIT_STUDIOLIGHT_ICON(ICON_STUDIOLIGHT_01, 0);
-	INIT_STUDIOLIGHT_ICON(ICON_STUDIOLIGHT_02, 1);
-	INIT_STUDIOLIGHT_ICON(ICON_STUDIOLIGHT_03, 2);
-	INIT_STUDIOLIGHT_ICON(ICON_STUDIOLIGHT_04, 3);
-	INIT_STUDIOLIGHT_ICON(ICON_STUDIOLIGHT_05, 4);
-
-}
 static void init_internal_icons(void)
 {
 //	bTheme *btheme = UI_GetTheme();
@@ -779,8 +763,9 @@ void UI_icons_free_drawinfo(void *drawinfo)
 /**
  * #Icon.data_type and #Icon.obj
  */
-static DrawInfo *icon_create_drawinfo(int icon_data_type)
+static DrawInfo *icon_create_drawinfo(Icon *icon)
 {
+	int  icon_data_type = icon->obj_type;
 	DrawInfo *di = NULL;
 
 	di = MEM_callocN(sizeof(DrawInfo), "di_icon");
@@ -791,6 +776,16 @@ static DrawInfo *icon_create_drawinfo(int icon_data_type)
 	else if (icon_data_type == ICON_DATA_GEOM) {
 		di->type = ICON_TYPE_GEOM;
 	}
+	else if (icon_data_type == ICON_DATA_STUDIOLIGHT) {
+		const int STUDIOLIGHT_SIZE = 96;
+		StudioLight *sl = icon->obj;
+		di->type = ICON_TYPE_BUFFER;
+		IconImage *img = MEM_mallocN(sizeof(IconImage), __func__);
+		img->w = STUDIOLIGHT_SIZE;
+		img->h = STUDIOLIGHT_SIZE;
+		img->rect = BKE_studiolight_preview(sl, STUDIOLIGHT_SIZE);
+		di->data.buffer.image = img;
+	}
 	else {
 		BLI_assert(0);
 	}
@@ -803,7 +798,7 @@ static DrawInfo *icon_ensure_drawinfo(Icon *icon)
 	if (icon->drawinfo) {
 		return icon->drawinfo;
 	}
-	DrawInfo *di = icon_create_drawinfo(icon->obj_type);
+	DrawInfo *di = icon_create_drawinfo(icon);
 	icon->drawinfo = di;
 	icon->drawinfo_free = UI_icons_free_drawinfo;
 	return di;
@@ -856,7 +851,6 @@ void UI_icons_init(int first_dyn_id)
 	init_internal_icons();
 	init_brush_icons();
 	init_matcap_icons();
-	init_studio_light_icons();
 #endif
 }
 
diff --git a/source/blender/makesdna/DNA_view3d_types.h b/source/blender/makesdna/DNA_view3d_types.h
index cf078bc203d..8a92ad25c92 100644
--- a/source/blender/makesdna/DNA_view3d_types.h
+++ b/source/blender/makesdna/DNA_view3d_types.h
@@ -138,7 +138,8 @@ typedef struct View3DShading {
 	short color_type;
 
 	short light;
-	short studio_light;
+	char pad[2];
+	char studio_light[256]; /* FILE_MAXFILE */
 
 	float shadow_intensity;
 	float single_color[3];
diff --git a/source/blender/makesrna/intern/rna_space.c b/source/blender/makesrna/intern/rna_space.c
index 124a0477f4c..d8c3fdd7a64 100644
--- a/source/blender/makesrna/intern/rna_space.c
+++ b/source/blender/makesrna/intern/rna_space.c
@@ -35,6 +35,7 @@
 #include "BKE_key.h"
 #include "BKE_movieclip.h"
 #include "BKE_node.h"
+#include "BKE_studiolight.h"
 
 #include "DNA_action_types.h"
 #include "DNA_key_types.h"
@@ -191,6 +192,31 @@ const EnumPropertyItem rna_enum_viewport_lighting_items[] = {
 	{0, NULL, 0, NULL, NULL}
 };
 
+static const EnumPropertyItem rna_enum_studio_light_items[] = {
+	{0, "STUDIOLIGHT_01", 0, "", ""},
+	{1, "STUDIOLIGHT_02", 0, "", ""},
+	{2, "STUDIOLIGHT_03", 0, "", ""},
+	{3, "STUDIOLIGHT_04", 0, "", ""},
+	{4, "STUDIOLIGHT_05", 0, "", ""},
+	{5, "STUDIOLIGHT_06", 0, "", ""},
+	{6, "STUDIOLIGHT_07", 0, "", ""},
+	{7, "STUDIOLIGHT_08", 0, "", ""},
+	{8, "STUDIOLIGHT_09", 0, "", ""},
+	{9, "STUDIOLIGHT_10", 0, "", ""},
+	{10, "STUDIOLIGHT_11", 0, "", ""},
+	{11, "STUDIOLIGHT_12", 0, "", ""},
+	{12, "STUDIOLIGHT_13", 0, "", ""},
+	{13, "STUDIOLIGHT_14", 0, "", ""},
+	{14, "STUDIOLIGHT_15", 0, "", ""},
+	{15, "STUDIOLIGHT_16", 0, "", ""},
+	{16, "STUDIOLIGHT_17", 0, "", ""},
+	{17, "STUDIOLIGHT_18", 0, "", ""},
+	{18, "STUDIOLIGHT_19", 0, "", ""},
+	{19, "STUDIOLIGHT_20", 0, "", ""},
+	{0, NULL, 0, NULL, NULL}
+};
+#define NUM_STUDIO_LIGHT_ITEMS 20
+
 const EnumPropertyItem rna_enum_clip_editor_mode_items[] = {
 	{SC_MODE_TRACKING, "TRACKING", ICON_ANIM_DATA, "Tracking", "Show tracking and solving tools"},
 	{SC_MODE_MASKEDIT, "MASK", ICON_MOD_MASK, "Mask", "Show mask editing tools"},
@@ -705,6 +731,42 @@ static const EnumPropertyItem *rna_3DViewShading_type_itemf(
 	return item;
 }
 
+static int rna_View3DShading_studio_light_get(PointerRNA *ptr)
+{
+	/* XXX: should be stored as string */
+	View3D *v3d = (View3D *)ptr->data;
+	StudioLight *sl = BKE_studiolight_find(v3d->shading.studio_light);
+	return sl->index;
+}
+
+static void rna_View3DShading_studio_light_set(PointerRNA *ptr, int value)
+{
+	/* XXX: should be stored as string */
+	View3D *v3d = (View3D *)ptr->data;
+	StudioLight *sl = BKE_studiolight_findindex(value);
+	BLI_strncpy(v3d->shading.studio_light, sl->name, FILE_MAXFILE);
+}
+
+static const EnumPropertyItem *rna_View3DShading_studio_light_itemf(
+        bContext *UNUSED(C), PointerRNA *UNUSED(ptr),
+        PropertyRNA *UNUSED(prop), bool *r_free)
+{
+	EnumPropertyItem *item = NULL;
+	int totitem = 0;
+
+	/* XXX: add studio lights */
+	LISTBASE_FOREACH(StudioLight*, sl, BKE_studiolight_listbase()) {
+		if (totitem < NUM_STUDIO_LIGHT_ITEMS) {
+			RNA_enum_items_add_value(&item, &totitem, rna_enum_studio_light_items, totitem);
+			item[totitem-1].icon = sl->icon_id;
+		}
+	}
+
+	RNA_enum_item_end(&item, &totitem);
+	*r_free = true;
+	return item;
+}
+
 static const EnumPropertyItem *rna_SpaceView3D_stereo3d_camera_itemf(
         bContext *C, PointerRNA *UNUSED(ptr),
         PropertyRNA *UNUSED(prop), bool *UNUSED(r_free))
@@ -2156,14 +2218,6 @@ static void rna_def_space_view3d_shading(BlenderRNA *brna)
 		{V3D_SHADING_RANDOM_COLOR,   "RANDOM",   0, "Random",   "Show random object color"},
 		{0, NULL, 0, NULL, NULL}
 	};
-	static const EnumPropertyItem studio_lighting_items[] = {
-		{0, "01", ICON_STUDIOLIGHT_01, "", ""},
-		{1, "02", ICON_STUDIOLIGHT_02, "", ""},
-		{2, "03", ICON_STUDIOLIGHT_03, "", ""},
-		{3, "04", ICON_STUDIOLIGHT_04, "", ""},
-		{4, "05", ICON_STUDIOLIGHT_05, "", ""},
-		{0, NULL, 0, NULL, NULL}
-	};
 
 	srna = RNA_def_struct(brna, "View3DShading", NULL);
 	RNA_def_struct_sdna(srna, "View3D");
@@ -2192,8 +2246,9 @@ static void rna_def_space_view3d_shading(BlenderRNA *brna)
 	RNA_def_property_update(prop, NC_SPACE | ND_SPACE_VIEW3D, NULL);
 
 	prop = RNA_def_property(srna, "studio_light", PROP_ENUM, PROP_NONE);
-	RNA_def_property_enum_sdna(prop, NULL, "shading.studio_light");
-	RNA_def_property_enum_items(prop, studio_lighting_items);
+	RNA_def_property_enum_items(prop, rna_enum_studio_light_items);
+	RNA_def_property_enum_default(prop, 0);
+	RNA_def_property_enum_funcs(prop, "rna_View3DShading_studio_light_get", "rna_View3DShading_studio_light_set", "rna_View3DShading_studio_light_itemf");
 	RNA_def_property_ui_text(prop, "Studiolight", "Studio lighting setup");
 	RNA_def_property_update(prop, NC_SPACE | ND_SPACE_VIEW3D, NULL);
 
diff --git a/source/blender/windowmanager/intern/wm_init_exit.c b/source/blender/windowmanager/intern/wm_init_exit.c
index 5813fc95e13..1dd2185b982 100644
--- a/source/blender/windowmanager/intern/wm_init_exit.c
+++ b/source/blender/windowmanager/intern/wm_init_exit.c
@@ -75,6 +75,7 @@
 #include "BKE_addon.h"
 #include "BKE_appdir.h"
 #include "BKE_sequencer.h" /* free seq clipboard */
+#include "BKE_studiolight.h"
 #include "BKE_material.h" /* clear_matcopybuf */
 #include "BKE_tracking.h" /* free tracking clipboard */
 #include "BKE_mask.h" /* free mask clipboard */
@@ -250,6 +251,7 @@ void WM_init(bContext *C, int argc, const char **argv)
 		WM_init_opengl();
 
 		UI_init();
+		BKE_studiolight_init();
 	}
 	else {
 		/* Note: Currently only inits icons, which we now want in background mode too
@@ -259,7 +261,6 @@ void WM_init(bContext *C, int argc, const char **argv)
 		BKE_icons_init(1);
 	}
 
-
 	ED_spacemacros_init();
 
 	/* note: there is a bug where python needs initializing before loading the
@@ -513,6 +514,7 @@ void WM_exit_ext(bContext *C, const bool do_python)
 		GPU_pass_cache_free();
 		DRW_opengl_context_destroy();
 	}
+	BKE_studiolight_free();
 
 #ifdef WITH_INTERNATIONAL
 	BLF_free_unifont();
diff --git a/source/creator/CMakeLists.txt b/source/creator/CMakeLists.txt
index 585a2f58204..8240b27f2cf 100644
--- a/source/creator/CMakeLists.txt
+++ b/source/creator/CMakeLists.txt
@@ -413,6 +413,7 @@ install(
 	DESTINATION ${TARGETDIR_VER}/datafiles
 )
 
+
 # helpful tip when using make
 if("${CMAKE_GENERATOR}" MATCHES ".*Makefiles.*")
 	# message after building.
@@ -979,6 +980,13 @@ unset(_icon_names)
 unset(_icon_files)
 unset(_f)
 
+# -----------------------------------------------------------------------------
+# Studio Lights
+install(
+	DIRECTORY
+		${CMAKE_SOURCE_DIR}/release/datafiles/studiolights
+	DESTINATION ${TARGETDIR_VER}/datafiles
+)
 
 # -----------------------------------------------------------------------------
 # Setup link libs