Studiolight: Spherical harmonics

Compile time option to reduce the level of the SH

7 files changed, 59 insertions, 17 deletions

diff --git a/source/blender/blenkernel/BKE_studiolight.h b/source/blender/blenkernel/BKE_studiolight.h
index f9d679b1b1a..af7ef9a383e 100644
--- a/source/blender/blenkernel/BKE_studiolight.h
+++ b/source/blender/blenkernel/BKE_studiolight.h
@@ -61,6 +61,22 @@
 
 #define STUDIOLIGHT_ICON_SIZE 96
 
+#define STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL 2
+#define STUDIOLIGHT_SPHERICAL_HARMONICS_MAX_COMPONENTS 9
+
+
+#if STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL == 0
+#define STUDIOLIGHT_SPHERICAL_HARMONICS_COMPONENTS 1
+#endif
+
+#if STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL == 1
+#define STUDIOLIGHT_SPHERICAL_HARMONICS_COMPONENTS 4
+#endif
+
+#if STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL == 2
+#define STUDIOLIGHT_SPHERICAL_HARMONICS_COMPONENTS 9
+#endif
+
 struct GPUTexture;
 struct StudioLight;
 
@@ -97,12 +113,12 @@ typedef struct StudioLight {
 	char name[FILE_MAXFILE];
 	char path[FILE_MAX];
 	char *path_irr_cache;
-	char *path_sh2_cache;
+	char *path_sh_cache;
 	int icon_id_irradiance;
 	int icon_id_radiance;
 	int icon_id_matcap;
 	int icon_id_matcap_flipped;
-	float spherical_harmonics_coefs[9][3];
+	float spherical_harmonics_coefs[STUDIOLIGHT_SPHERICAL_HARMONICS_COMPONENTS][3];
 	float light_direction[3];
 	ImBuf *equirectangular_radiance_buffer;
 	ImBuf *equirectangular_irradiance_buffer;
diff --git a/source/blender/blenkernel/intern/studiolight.c b/source/blender/blenkernel/intern/studiolight.c
index 121100570a2..62361917f2f 100644
--- a/source/blender/blenkernel/intern/studiolight.c
+++ b/source/blender/blenkernel/intern/studiolight.c
@@ -110,7 +110,7 @@ static void studiolight_free(struct StudioLight *sl)
 	IMB_SAFE_FREE(sl->equirectangular_radiance_buffer);
 	IMB_SAFE_FREE(sl->equirectangular_irradiance_buffer);
 	MEM_SAFE_FREE(sl->path_irr_cache);
-	MEM_SAFE_FREE(sl->path_sh2_cache);
+	MEM_SAFE_FREE(sl->path_sh_cache);
 	MEM_SAFE_FREE(sl->gpu_matcap_3components);
 	MEM_SAFE_FREE(sl);
 }
@@ -121,7 +121,7 @@ static struct StudioLight *studiolight_create(int flag)
 	sl->path[0] = 0x00;
 	sl->name[0] = 0x00;
 	sl->path_irr_cache = NULL;
-	sl->path_sh2_cache = NULL;
+	sl->path_sh_cache = NULL;
 	sl->free_function = NULL;
 	sl->flag = flag;
 	sl->index = BLI_listbase_count(&studiolights);
@@ -478,14 +478,11 @@ static void studiolight_calculate_diffuse_light(StudioLight *sl)
 	if (sl->flag & STUDIOLIGHT_EXTERNAL_FILE) {
 		BKE_studiolight_ensure_flag(sl, STUDIOLIGHT_RADIANCE_BUFFERS_CALCULATED);
 
-		for (int comp = 0; comp < 9; comp ++) {
+		for (int comp = 0; comp < STUDIOLIGHT_SPHERICAL_HARMONICS_COMPONENTS; comp ++) {
 			studiolight_calculate_spherical_harmonics_coefficient(sl, comp);
-#if 0
-			print_v3("SH2", sl->spherical_harmonics_coefs[comp]);
-#endif
 		}
 		if (sl->flag & STUDIOLIGHT_USER_DEFINED) {
-			FILE *fp = BLI_fopen(sl->path_sh2_cache, "wb");
+			FILE *fp = BLI_fopen(sl->path_sh_cache, "wb");
 			if (fp) {
 				fwrite(sl->spherical_harmonics_coefs, sizeof(sl->spherical_harmonics_coefs), 1, fp);
 				fclose(fp);
@@ -593,7 +590,7 @@ static bool studiolight_load_spherical_harmonics_coefficients(StudioLight *sl)
 {
 #ifdef STUDIOLIGHT_LOAD_CACHED_FILES
 	if (sl->flag & STUDIOLIGHT_EXTERNAL_FILE) {
-		FILE *fp = BLI_fopen(sl->path_sh2_cache, "rb");
+		FILE *fp = BLI_fopen(sl->path_sh_cache, "rb");
 		if (fp) {
 			if (fread((void*)(sl->spherical_harmonics_coefs), sizeof(sl->spherical_harmonics_coefs), 1, fp))
 			{
@@ -693,7 +690,7 @@ static void studiolight_add_files_from_datafolder(const int folder_id, const cha
 					BLI_strncpy(sl->name, filename, FILE_MAXFILE);
 					BLI_strncpy(sl->path, path, FILE_MAXFILE);
 					sl->path_irr_cache = BLI_string_joinN(path, ".irr");
-					sl->path_sh2_cache = BLI_string_joinN(path, ".sh2");
+					sl->path_sh_cache = BLI_string_joinN(path, ".sh2");
 					BLI_addtail(&studiolights, sl);
 				}
 			}
@@ -853,17 +850,21 @@ static void studiolight_irradiance_preview(uint* icon_buffer, StudioLight *sl)
 				/* Spherical Harmonics L0 */
 				madd_v3_v3fl(color, sl->spherical_harmonics_coefs[0], 0.282095f);
 
+#if STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL > 0
 				/* Spherical Harmonics L1 */
 				madd_v3_v3fl(color, sl->spherical_harmonics_coefs[1], -0.488603f * normal[2]);
 				madd_v3_v3fl(color, sl->spherical_harmonics_coefs[2],  0.488603f * normal[1]);
 				madd_v3_v3fl(color, sl->spherical_harmonics_coefs[3], -0.488603f * normal[0]);
+#endif
 
+#if STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL > 1
 				/* Spherical Harmonics L1 */
 				madd_v3_v3fl(color, sl->spherical_harmonics_coefs[4], 1.092548f * normal[0] * normal[2]);
 				madd_v3_v3fl(color, sl->spherical_harmonics_coefs[5], -1.092548f * normal[2] * normal[1]);
 				madd_v3_v3fl(color, sl->spherical_harmonics_coefs[6], 0.315392f * (3.0f * normal[1] * normal[1] - 1.0f));
 				madd_v3_v3fl(color, sl->spherical_harmonics_coefs[7], -1.092548 * normal[0] * normal[1]);
 				madd_v3_v3fl(color, sl->spherical_harmonics_coefs[8], 0.546274 * (normal[0] * normal[0] - normal[2] * normal[2]));
+#endif
 				pixelresult = rgb_to_cpack(
 				        linearrgb_to_srgb(color[0]),
 				        linearrgb_to_srgb(color[1]),
@@ -885,15 +886,20 @@ void BKE_studiolight_init(void)
 	sl = studiolight_create(STUDIOLIGHT_INTERNAL | STUDIOLIGHT_SPHERICAL_HARMONICS_COEFFICIENTS_CALCULATED | STUDIOLIGHT_ORIENTATION_CAMERA);
 	BLI_strncpy(sl->name, "Default", FILE_MAXFILE);
 
+
 	copy_v3_fl3(sl->spherical_harmonics_coefs[0], 1.03271556f, 1.07163882f, 1.11193657f);
+#if STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL > 0
 	copy_v3_fl3(sl->spherical_harmonics_coefs[1], -0.00480952f, 0.05290511f, 0.16394117f);
 	copy_v3_fl3(sl->spherical_harmonics_coefs[2], -0.29686999f, -0.27378261f, -0.24797194f);
 	copy_v3_fl3(sl->spherical_harmonics_coefs[3], 0.47932500f, 0.48242140f, 0.47190312f);
+#endif
+#if STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL > 1
 	copy_v3_fl3(sl->spherical_harmonics_coefs[4], -0.00576984f, 0.00504886f, 0.01640534f);
 	copy_v3_fl3(sl->spherical_harmonics_coefs[5], 0.15500379f, 0.15415503f, 0.16244425f);
 	copy_v3_fl3(sl->spherical_harmonics_coefs[6], -0.02483751f, -0.02245096f, -0.00536885f);
 	copy_v3_fl3(sl->spherical_harmonics_coefs[7], 0.11155496f, 0.11005443f, 0.10839636f);
 	copy_v3_fl3(sl->spherical_harmonics_coefs[8], 0.01363425f, 0.01278363f, -0.00159006f);
+#endif
 
 	BLI_addtail(&studiolights, sl);
 
diff --git a/source/blender/draw/engines/workbench/shaders/workbench_data_lib.glsl b/source/blender/draw/engines/workbench/shaders/workbench_data_lib.glsl
index 2ba6e0e8e55..2d913c63b00 100644
--- a/source/blender/draw/engines/workbench/shaders/workbench_data_lib.glsl
+++ b/source/blender/draw/engines/workbench/shaders/workbench_data_lib.glsl
@@ -4,7 +4,7 @@ struct LightData {
 };
 
 struct WorldData {
-	vec3 spherical_harmonics_coefs[9];
+	vec3 spherical_harmonics_coefs[STUDIOLIGHT_SPHERICAL_HARMONICS_MAX_COMPONENTS];
 	vec4 background_color_low;
 	vec4 background_color_high;
 	vec4 object_outline_color;
diff --git a/source/blender/draw/engines/workbench/shaders/workbench_world_light_lib.glsl b/source/blender/draw/engines/workbench/shaders/workbench_world_light_lib.glsl
index 71adc751f0a..b13c4f1b43b 100644
--- a/source/blender/draw/engines/workbench/shaders/workbench_world_light_lib.glsl
+++ b/source/blender/draw/engines/workbench/shaders/workbench_world_light_lib.glsl
@@ -1,32 +1,36 @@
 #define BLINN
 
-vec3 spherical_harmonics_L2(vec3 N, vec3 spherical_harmonics_coefs[9])
+vec3 spherical_harmonics(vec3 N, vec3 spherical_harmonics_coefs[STUDIOLIGHT_SPHERICAL_HARMONICS_MAX_COMPONENTS])
 {
 	vec3 sh = vec3(0.0);
 
 	sh += 0.282095 * spherical_harmonics_coefs[0];
 
+#if STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL > 0
 	sh += -0.488603 * N.z * spherical_harmonics_coefs[1];
 	sh += 0.488603 * N.y * spherical_harmonics_coefs[2];
 	sh += -0.488603 * N.x * spherical_harmonics_coefs[3];
+#endif
 
+#if STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL > 1
 	sh += 1.092548 * N.x * N.z * spherical_harmonics_coefs[4];
 	sh += -1.092548 * N.z * N.y * spherical_harmonics_coefs[5];
 	sh += 0.315392 * (3.0 * N.y * N.y - 1.0) * spherical_harmonics_coefs[6];
 	sh += -1.092548 * N.x * N.y * spherical_harmonics_coefs[7];
 	sh += 0.546274 * (N.x * N.x - N.z * N.z) * spherical_harmonics_coefs[8];
+#endif
 
 	return sh;
 }
 
 vec3 get_world_diffuse_light(WorldData world_data, vec3 N)
 {
-	return (spherical_harmonics_L2(vec3(N.x, N.y, -N.z), world_data.spherical_harmonics_coefs));
+	return (spherical_harmonics(vec3(N.x, N.y, -N.z), world_data.spherical_harmonics_coefs));
 }
 
 vec3 get_camera_diffuse_light(WorldData world_data, vec3 N)
 {
-	return (spherical_harmonics_L2(vec3(N.x, -N.z, -N.y), world_data.spherical_harmonics_coefs));
+	return (spherical_harmonics(vec3(N.x, -N.z, -N.y), world_data.spherical_harmonics_coefs));
 }
 
 /* N And I are in View Space. */
diff --git a/source/blender/draw/engines/workbench/workbench_materials.c b/source/blender/draw/engines/workbench/workbench_materials.c
index 231d9a9582a..c0857cf74aa 100644
--- a/source/blender/draw/engines/workbench/workbench_materials.c
+++ b/source/blender/draw/engines/workbench/workbench_materials.c
@@ -95,6 +95,17 @@ char *workbench_material_build_defines(WORKBENCH_PrivateData *wpd, int drawtype,
 		BLI_dynstr_appendf(ds, "#define HAIR_SHADER\n");
 	}
 
+#if STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL == 0
+	BLI_dynstr_appendf(ds, "#define STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL 0\n");
+#endif
+#if STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL == 1
+	BLI_dynstr_appendf(ds, "#define STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL 1\n");
+#endif
+#if STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL == 2
+	BLI_dynstr_appendf(ds, "#define STUDIOLIGHT_SPHERICAL_HARMONICS_LEVEL 2\n");
+#endif
+	BLI_dynstr_appendf(ds, "#define STUDIOLIGHT_SPHERICAL_HARMONICS_MAX_COMPONENTS 9\n");
+
 	str = BLI_dynstr_get_cstring(ds);
 	BLI_dynstr_free(ds);
 	return str;
diff --git a/source/blender/draw/engines/workbench/workbench_private.h b/source/blender/draw/engines/workbench/workbench_private.h
index 9e43a5c4a48..68d50a85c35 100644
--- a/source/blender/draw/engines/workbench/workbench_private.h
+++ b/source/blender/draw/engines/workbench/workbench_private.h
@@ -112,7 +112,7 @@ typedef struct WORKBENCH_UBO_Light {
 } WORKBENCH_UBO_Light;
 
 typedef struct WORKBENCH_UBO_World {
-	float spherical_harmonics_coefs[9][4];
+	float spherical_harmonics_coefs[STUDIOLIGHT_SPHERICAL_HARMONICS_MAX_COMPONENTS][4];
 	float background_color_low[4];
 	float background_color_high[4];
 	float object_outline_color[4];
diff --git a/source/blender/draw/engines/workbench/workbench_studiolight.c b/source/blender/draw/engines/workbench/workbench_studiolight.c
index f2453bf7070..f9e5df91388 100644
--- a/source/blender/draw/engines/workbench/workbench_studiolight.c
+++ b/source/blender/draw/engines/workbench/workbench_studiolight.c
@@ -34,10 +34,15 @@
 
 void studiolight_update_world(StudioLight *sl, WORKBENCH_UBO_World *wd)
 {
+	int i;
 	BKE_studiolight_ensure_flag(sl, STUDIOLIGHT_SPHERICAL_HARMONICS_COEFFICIENTS_CALCULATED);
-	for (int i = 0; i < 9; i++) {
+
+	for (i = 0; i < STUDIOLIGHT_SPHERICAL_HARMONICS_COMPONENTS; i++) {
 		copy_v3_v3(wd->spherical_harmonics_coefs[i], sl->spherical_harmonics_coefs[i]);
 	}
+	for (; i < STUDIOLIGHT_SPHERICAL_HARMONICS_MAX_COMPONENTS; i++) {
+		copy_v3_fl(wd->spherical_harmonics_coefs[i], 0.0);
+	}
 }
 
 static void compute_parallel_lines_nor_and_dist(const float v1[2], const float v2[2], const float v3[2], float r_line[2])