[Bf-blender-cvs] [7bb512594cd] blender2.8: Workbench: Use non-negative lighting evaluation
Clément Foucault
noreply at git.blender.org
Mon Nov 19 18:05:28 CET 2018
Commit: 7bb512594cd9502fea290ac6124f2eb5fd3cfce8
Author: Clément Foucault
Date: Mon Nov 19 18:03:06 2018 +0100
Branches: blender2.8
https://developer.blender.org/rB7bb512594cd9502fea290ac6124f2eb5fd3cfce8
Workbench: Use non-negative lighting evaluation
This makes the lighting a bit more diffuse but don't produce negative
values.
Add a bias of 1.5f to make the lighting a bit more directionnal.
The implementation is based on:
https://github.com/kayru/Probulator/blob/master/Source/Probulator/SphericalHarmonics.h#L136
which is derived from:
http://www.geomerics.com/wp-content/uploads/2015/08/CEDEC_Geomerics_ReconstructingDiffuseLighting1.pdf
The shader implementation is optimized and has the same runtime cost
as previous method:
* no sh eval : 0.13ms
* prev sh eval : 0.14ms
* new sh eval : 0.22ms
* new sh eval opti : 0.14ms
===================================================================
M source/blender/blenkernel/BKE_studiolight.h
M source/blender/blenkernel/intern/studiolight.c
M source/blender/draw/engines/workbench/shaders/workbench_world_light_lib.glsl
M source/blender/draw/engines/workbench/workbench_materials.c
M source/blender/draw/engines/workbench/workbench_private.h
M source/blender/draw/engines/workbench/workbench_studiolight.c
===================================================================
diff --git a/source/blender/blenkernel/BKE_studiolight.h b/source/blender/blenkernel/BKE_studiolight.h
index cbb911ee32c..7ec98c99c3f 100644
--- a/source/blender/blenkernel/BKE_studiolight.h
+++ b/source/blender/blenkernel/BKE_studiolight.h
@@ -62,7 +62,7 @@
#define STUDIOLIGHT_ICON_SIZE 96
/* Only 1 - 5 is supported */
-#define STUDIOLIGHT_SH_BANDS 3
+#define STUDIOLIGHT_SH_BANDS 2
#define STUDIOLIGHT_SH_COEFS_LEN (STUDIOLIGHT_SH_BANDS * STUDIOLIGHT_SH_BANDS)
diff --git a/source/blender/blenkernel/intern/studiolight.c b/source/blender/blenkernel/intern/studiolight.c
index d04c14299dc..736a06a3148 100644
--- a/source/blender/blenkernel/intern/studiolight.c
+++ b/source/blender/blenkernel/intern/studiolight.c
@@ -558,19 +558,45 @@ static void studiolight_spherical_harmonics_apply_windowing(float (*sh)[3], floa
}
}
-BLI_INLINE void studiolight_spherical_harmonics_eval(StudioLight *sl, float color[3], float normal[3])
+static float studiolight_spherical_harmonics_geomerics_eval(const float normal[3], float sh0, float sh1, float sh2, float sh3)
{
+ /* Use Geomerics non-linear SH. */
+ /* http://www.geomerics.com/wp-content/uploads/2015/08/CEDEC_Geomerics_ReconstructingDiffuseLighting1.pdf */
+ float R0 = sh0 * M_1_PI;
+
+ float R1[3] = {-sh3, sh2, -sh1};
+ mul_v3_fl(R1, 0.5f * M_1_PI * 1.5f); /* 1.5f is to improve the contrast a bit. */
+ float lenR1 = len_v3(R1);
+ mul_v3_fl(R1, 1.0f / lenR1);
+ float q = 0.5f * (1.0f + dot_v3v3(R1, normal));
+
+ float p = 1.0f + 2.0f * lenR1 / R0;
+ float a = (1.0f - lenR1 / R0) / (1.0f + lenR1 / R0);
+
+ return R0 * (a + (1.0f - a) * (p + 1.0f) * powf(q, p));
+}
+
+BLI_INLINE void studiolight_spherical_harmonics_eval(StudioLight *sl, float color[3], const float normal[3])
+{
+#if STUDIOLIGHT_SH_BANDS == 2
+ float (*sh)[3] = (float (*)[3])sl->spherical_harmonics_coefs;
+ for (int i = 0; i < 3; ++i) {
+ color[i] = studiolight_spherical_harmonics_geomerics_eval(normal, sh[0][i], sh[1][i], sh[2][i], sh[3][i]);
+ }
+ return;
+#else
+
/* L0 */
mul_v3_v3fl(color, sl->spherical_harmonics_coefs[0], 0.282095f);
-#if STUDIOLIGHT_SH_BANDS > 1 /* L1 */
+# if STUDIOLIGHT_SH_BANDS > 1 /* L1 */
const float nx = normal[0];
const float ny = normal[1];
const float nz = normal[2];
madd_v3_v3fl(color, sl->spherical_harmonics_coefs[1], -0.488603f * nz);
madd_v3_v3fl(color, sl->spherical_harmonics_coefs[2], 0.488603f * ny);
madd_v3_v3fl(color, sl->spherical_harmonics_coefs[3], -0.488603f * nx);
-#endif
-#if STUDIOLIGHT_SH_BANDS > 2 /* L2 */
+# endif
+# if STUDIOLIGHT_SH_BANDS > 2 /* L2 */
const float nx2 = SQUARE(nx);
const float ny2 = SQUARE(ny);
const float nz2 = SQUARE(nz);
@@ -579,9 +605,9 @@ BLI_INLINE void studiolight_spherical_harmonics_eval(StudioLight *sl, float colo
madd_v3_v3fl(color, sl->spherical_harmonics_coefs[6], 0.315392f * (3.0f * ny2 - 1.0f));
madd_v3_v3fl(color, sl->spherical_harmonics_coefs[7], -1.092548 * nx * ny);
madd_v3_v3fl(color, sl->spherical_harmonics_coefs[8], 0.546274 * (nx2 - nz2));
-#endif
+# endif
/* L3 coefs are 0 */
-#if STUDIOLIGHT_SH_BANDS > 4 /* L4 */
+# if STUDIOLIGHT_SH_BANDS > 4 /* L4 */
const float nx4 = SQUARE(nx2);
const float ny4 = SQUARE(ny2);
const float nz4 = SQUARE(nz2);
@@ -594,6 +620,7 @@ BLI_INLINE void studiolight_spherical_harmonics_eval(StudioLight *sl, float colo
madd_v3_v3fl(color, sl->spherical_harmonics_coefs[15], 0.9461746957575601f * (nx2 - nz2) * (-1.0f + 7.0f * ny2));
madd_v3_v3fl(color, sl->spherical_harmonics_coefs[16], -1.7701307697799304f * nx * ny * (nx2 - 3.0f * nz2));
madd_v3_v3fl(color, sl->spherical_harmonics_coefs[17], 0.6258357354491761f * (nx4 - 6.0f * nz2 * nx2 + nz4));
+# endif
#endif
}
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 1b93fc0014c..ab48aa5fa03 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
@@ -1,18 +1,50 @@
#define BLINN
+#if STUDIOLIGHT_SH_BANDS == 2
+vec3 spherical_harmonics(vec3 N, vec3 sh_coefs[STUDIOLIGHT_SH_MAX_COMPONENTS])
+{
+ /* http://www.geomerics.com/wp-content/uploads/2015/08/CEDEC_Geomerics_ReconstructingDiffuseLighting1.pdf */
+ /* Highly optimized form, precompute as much as we can. */
+ /**
+ * R1 = 0.5 * vec3(L3.r, L2.r, L1.r);
+ * sh_coefs[0..2] = R1 / length(R1);
+ **/
+ vec3 q;
+ q.x = dot(sh_coefs[1], N);
+ q.y = dot(sh_coefs[2], N);
+ q.z = dot(sh_coefs[3], N);
+ q = 0.5 * q + 0.5;
+
+ /**
+ * R0 = L0.r;
+ * lr1_r0 = lenR1 / R0;
+ * p = 1.0 + 2.0 * lr1_r0;
+ * a = (1.0 - lr1_r0) / (1.0 + lr1_r0);
+ * return R0 * (a + (1.0 - a) * (p + 1.0) * pow(q, p));
+ *
+ * sh_coefs[4] = p;
+ * sh_coefs[5] = R0 * a;
+ * sh_coefs[0] = R0 * (1.0 - a) * (p + 1.0);
+ **/
+ q = pow(q, sh_coefs[4]);
+ return sh_coefs[0] * q + sh_coefs[5];
+}
+
+#else
+
vec3 spherical_harmonics(vec3 N, vec3 sh_coefs[STUDIOLIGHT_SH_MAX_COMPONENTS])
{
vec3 sh = 0.282095 * sh_coefs[0];
-#if STUDIOLIGHT_SH_BANDS > 1
+# if STUDIOLIGHT_SH_BANDS > 1
float nx = N.x;
float ny = N.y;
float nz = N.z;
sh += -0.488603 * nz * sh_coefs[1];
sh += 0.488603 * ny * sh_coefs[2];
sh += -0.488603 * nx * sh_coefs[3];
-#endif
-#if STUDIOLIGHT_SH_BANDS > 2
+# endif
+# if STUDIOLIGHT_SH_BANDS > 2
float nx2 = nx * nx;
float ny2 = ny * ny;
float nz2 = nz * nz;
@@ -21,8 +53,8 @@ vec3 spherical_harmonics(vec3 N, vec3 sh_coefs[STUDIOLIGHT_SH_MAX_COMPONENTS])
sh += 0.315392 * (3.0 * ny2 - 1.0) * sh_coefs[6];
sh += -1.092548 * nx * ny * sh_coefs[7];
sh += 0.546274 * (nx2 - nz2) * sh_coefs[8];
-#endif
-#if STUDIOLIGHT_SH_BANDS > 4
+# endif
+# if STUDIOLIGHT_SH_BANDS > 4
float nx4 = nx2 * nx2;
float ny4 = ny2 * ny2;
float nz4 = nz2 * nz2;
@@ -35,9 +67,10 @@ vec3 spherical_harmonics(vec3 N, vec3 sh_coefs[STUDIOLIGHT_SH_MAX_COMPONENTS])
sh += (0.9461746957575601 * (nx2 - nz2) * (-1.0 + 7.0 * ny2)) * sh_coefs[15];
sh += (-1.7701307697799304 * nx * ny * (nx2 - 3.0 * nz2)) * sh_coefs[16];
sh += (0.6258357354491761 * (nx4 - 6.0 * nz2 * nx2 + nz4)) * sh_coefs[17];
-#endif
+# endif
return sh;
}
+#endif
vec3 get_world_diffuse_light(WorldData world_data, vec3 N)
{
diff --git a/source/blender/draw/engines/workbench/workbench_materials.c b/source/blender/draw/engines/workbench/workbench_materials.c
index 14b4c5e6f4c..572a26c86bd 100644
--- a/source/blender/draw/engines/workbench/workbench_materials.c
+++ b/source/blender/draw/engines/workbench/workbench_materials.c
@@ -92,7 +92,7 @@ char *workbench_material_build_defines(WORKBENCH_PrivateData *wpd, bool use_text
}
BLI_dynstr_appendf(ds, "#define STUDIOLIGHT_SH_BANDS %d\n", STUDIOLIGHT_SH_BANDS);
- BLI_dynstr_appendf(ds, "#define STUDIOLIGHT_SH_MAX_COMPONENTS %d\n", STUDIOLIGHT_SH_EFFECTIVE_COEFS_LEN);
+ BLI_dynstr_appendf(ds, "#define STUDIOLIGHT_SH_MAX_COMPONENTS %d\n", WORKBENCH_SH_DATA_LEN);
str = BLI_dynstr_get_cstring(ds);
BLI_dynstr_free(ds);
diff --git a/source/blender/draw/engines/workbench/workbench_private.h b/source/blender/draw/engines/workbench/workbench_private.h
index ef18c00cff3..93b3bddfb72 100644
--- a/source/blender/draw/engines/workbench/workbench_private.h
+++ b/source/blender/draw/engines/workbench/workbench_private.h
@@ -138,8 +138,10 @@ typedef struct WORKBENCH_UBO_Light {
float energy;
} WORKBENCH_UBO_Light;
+#define WORKBENCH_SH_DATA_LEN ((STUDIOLIGHT_SH_BANDS == 2) ? 6 : STUDIOLIGHT_SH_EFFECTIVE_COEFS_LEN)
+
typedef struct WORKBENCH_UBO_World {
- float spherical_harmonics_coefs[STUDIOLIGHT_SH_EFFECTIVE_COEFS_LEN][4];
+ float spherical_harmonics_coefs[WORKBENCH_SH_DATA_LEN][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 c852d7abb90..65732b52471 100644
--- a/source/blender/draw/engines/workbench/workbench_studiolight.c
+++ b/source/blender/draw/engines/workbench/workbench_studiolight.c
@@ -36,10 +36,55 @@ void studiolight_update_world(StudioLight *sl, WORKBENCH_UBO_World *wd)
{
BKE_studiolight_ensure_flag(sl, STUDIOLIGHT_SPHERICAL_HARMONICS_COEFFICIENTS_CALCULATED);
+#if STUDIOLIGHT_SH_BANDS == 2
+ /* Use Geomerics non-linear SH. */
+ mul_v3_v3fl(wd->spherical_harmonics_coefs[0], sl->spherical_harmonics_coefs[0], M_1_PI);
+ /* Swizzle to make shader code simpler. */
+ for (int i = 0; i < 3; ++i) {
+ copy_v3_fl3(wd->spherical_harmonics_coefs[i+1], -sl->spherical_harmonics_coefs[3][i],
+ sl->spherical_harmonics_coefs[2][i],
+ -sl->spherical_harmonics_coefs[1][i]);
+ mul_v3_fl(wd->spherical_harmonics_coefs[i+1], M_1_PI * 1.5f); /* 1.5f is to improve the contrast a bit. */
+ }
+
+ /* Precompute as much as we can. See shader code for derivation. */
+ float len_r1[3], lr1_r0[3], p[3], a[3];
+ for (int i = 0; i < 3; ++i) {
+ mul_v3_fl(wd->spherical_harmonics_coefs[i+1], 0.5f);
+ len_r1[i] = len_v3(wd->spherical_harmonics_coefs[i+1]);
+ mul_v3_fl(wd->spherical_harmonics_coefs[i+1], 1.0f / len_r1[i]);
+ }
+ /* lr1_r0 = lenR1 / R0; */
+ copy_v3_v3(lr1_r0, wd->spherical_harmonics_coefs[0]);
+ invert_v3(lr1_r0);
+ mul_v3_v3(lr1_r0, len_r1);
+ /* p = 1.0 + 2.0 * lr1_r0; */
+ copy_v3_v3(p, lr1_r0);
+ mul_v3_fl(p, 2.0f);
+ add_v3_fl(p, 1.0f);
+ /* a = (1.0 - lr1_r0) / (1.0 + lr1_r0); */
+ copy_v3_v3(a, lr1_r0);
+ add_v3_fl(a, 1.0f);
+ invert_v3(a);
+ negate_v3(lr1_r0);
+ add_v3_fl(lr1_r0, 1.0f);
+ mul_v3_v3(a, lr1_r0);
+ /* sh_coefs[4] = p; */
+ copy_v3_v3(wd->spherical_harmonics_coefs[4], p);
+ /* sh_coefs[5] = R0 * a; */
+ mul_v3_v3v3(wd->spherical_harmonics_coefs[5], wd->spherical_harmonics_coefs[0], a);
+ /* sh_coefs[0] = R0 * (1.0 - a) * (p + 1.0); */
+ negate_v3(a);
+ add_v3_fl(a, 1.0f);
+ add_v3_fl(p, 1.0f);
+ mul_v3_v3(a, p);
+ mul_v3_v3(wd->spherical_harmonics_coefs[0], a);
+#else
for (int i = 0; i < STUDIOLIGHT_SH_EFFECTIVE_COEFS_LEN; i++) {
/* Can't memcpy because of alignment */
copy_v3_v3(wd->spherical_harmonics_c
@@ Diff output truncated at 10240 characters. @@
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