Merge branch 'blender-v3.2-release'

5 files changed, 38 insertions, 36 deletions

diff --git a/intern/cycles/kernel/svm/blackbody.h b/intern/cycles/kernel/svm/blackbody.h
index af59c2fe747..774fa16b384 100644
--- a/intern/cycles/kernel/svm/blackbody.h
+++ b/intern/cycles/kernel/svm/blackbody.h
@@ -24,6 +24,7 @@ ccl_device_noinline void svm_node_blackbody(KernelGlobals kg,
   float temperature = stack_load_float(stack, temperature_offset);
 
   float3 color_rgb = rec709_to_rgb(kg, svm_math_blackbody_color_rec709(temperature));
+  color_rgb = max(color_rgb, zero_float3());
 
   stack_store_float3(stack, col_offset, color_rgb);
 }
diff --git a/intern/cycles/kernel/svm/math_util.h b/intern/cycles/kernel/svm/math_util.h
index 9f2d9561e26..89bd4a501a7 100644
--- a/intern/cycles/kernel/svm/math_util.h
+++ b/intern/cycles/kernel/svm/math_util.h
@@ -192,28 +192,26 @@ ccl_device float svm_math(NodeMathType type, float a, float b, float c)
 ccl_device float3 svm_math_blackbody_color_rec709(float t)
 {
   /* Calculate color in range 800..12000 using an approximation
-   * a/x+bx+c for R and G and ((at + b)t + c)t + d) for B
-   * Max absolute error for RGB is (0.00095, 0.00077, 0.00057),
-   * which is enough to get the same 8 bit/channel color.
-   */
+   * a/x+bx+c for R and G and ((at + b)t + c)t + d) for B.
+   *
+   * The result of this can be negative to support gamut wider than
+   * than rec.709, just needs to be clamped. */
 
   if (t >= 12000.0f) {
-    return make_float3(0.826270103f, 0.994478524f, 1.56626022f);
+    return make_float3(0.8262954810464208f, 0.9945080501520986f, 1.566307710274283f);
   }
-  else if (t < 965.0f) {
-    /* For 800 <= t < 965 color does not change in OSL implementation, so keep color the same */
-    return make_float3(4.70366907f, 0.0f, 0.0f);
+  else if (t < 800.0f) {
+    /* Arbitrary lower limit where light is very dim, matching OSL. */
+    return make_float3(5.413294490189271f, -0.20319390035873933f, -0.0822535242887164f);
   }
 
-  /* Manually align for readability. */
-  /* clang-format off */
-  int i = (t >= 6365.0f) ? 5 :
-          (t >= 3315.0f) ? 4 :
-          (t >= 1902.0f) ? 3 :
-          (t >= 1449.0f) ? 2 :
-          (t >= 1167.0f) ? 1 :
+  int i = (t >= 6365.0f) ? 6 :
+          (t >= 3315.0f) ? 5 :
+          (t >= 1902.0f) ? 4 :
+          (t >= 1449.0f) ? 3 :
+          (t >= 1167.0f) ? 2 :
+          (t >= 965.0f)  ? 1 :
                            0;
-  /* clang-format on */
 
   ccl_constant float *r = blackbody_table_r[i];
   ccl_constant float *g = blackbody_table_g[i];
diff --git a/intern/cycles/kernel/tables.h b/intern/cycles/kernel/tables.h
index f826cc5c5ef..c1fdbba3fa7 100644
--- a/intern/cycles/kernel/tables.h
+++ b/intern/cycles/kernel/tables.h
@@ -4,30 +4,33 @@
 /* clang-format off */
 
 ccl_inline_constant float blackbody_table_r[][3] = {
-  {2.52432244e+03f, -1.06185848e-03f, 3.11067539e+00f},
-  {3.37763626e+03f, -4.34581697e-04f, 1.64843306e+00f},
-  {4.10671449e+03f, -8.61949938e-05f, 6.41423749e-01f},
-  {4.66849800e+03f, 2.85655028e-05f, 1.29075375e-01f},
-  {4.60124770e+03f, 2.89727618e-05f, 1.48001316e-01f},
-  {3.78765709e+03f, 9.36026367e-06f, 3.98995841e-01f}
+ {1.61919106e+03f, -2.05010916e-03f, 5.02995757e+00f},
+ {2.48845471e+03f, -1.11330907e-03f, 3.22621544e+00f},
+ {3.34143193e+03f, -4.86551192e-04f, 1.76486769e+00f},
+ {4.09461742e+03f, -1.27446582e-04f, 7.25731635e-01f},
+ {4.67028036e+03f, 2.91258199e-05f, 1.26703442e-01f},
+ {4.59509185e+03f, 2.87495649e-05f, 1.50345020e-01f},
+ {3.78717450e+03f, 9.35907826e-06f, 3.99075871e-01f}
 };
 
 ccl_inline_constant float blackbody_table_g[][3] = {
-  {-7.50343014e+02f, 3.15679613e-04f, 4.73464526e-01f},
-  {-1.00402363e+03f, 1.29189794e-04f, 9.08181524e-01f},
-  {-1.22075471e+03f, 2.56245413e-05f, 1.20753416e+00f},
-  {-1.42546105e+03f, -4.01730887e-05f, 1.44002695e+00f},
-  {-1.18134453e+03f, -2.18913373e-05f, 1.30656109e+00f},
-  {-5.00279505e+02f, -4.59745390e-06f, 1.09090465e+00f}
+ {-4.88999748e+02f, 6.04330754e-04f, -7.55807526e-02f},
+ {-7.55994277e+02f, 3.16730098e-04f, 4.78306139e-01f},
+ {-1.02363977e+03f, 1.20223470e-04f, 9.36662319e-01f},
+ {-1.26571316e+03f, 4.87340896e-06f, 1.27054498e+00f},
+ {-1.42529332e+03f, -4.01150431e-05f, 1.43972784e+00f},
+ {-1.17554822e+03f, -2.16378048e-05f, 1.30408023e+00f},
+ {-5.00799571e+02f, -4.59832026e-06f, 1.09098763e+00f}
 };
 
 ccl_inline_constant float blackbody_table_b[][4] = {
-  {0.0f, 0.0f, 0.0f, 0.0f}, /* zeros should be optimized by compiler */
-  {0.0f, 0.0f, 0.0f, 0.0f},
-  {0.0f, 0.0f, 0.0f, 0.0f},
-  {-2.02524603e-11f, 1.79435860e-07f, -2.60561875e-04f, -1.41761141e-02f},
-  {-2.22463426e-13f, -1.55078698e-08f, 3.81675160e-04f, -7.30646033e-01f},
-  {6.72595954e-13f, -2.73059993e-08f, 4.24068546e-04f, -7.52204323e-01f}
+ {5.96945309e-11f, -4.85742887e-08f, -9.70622247e-05f, -4.07936148e-03f},
+ {2.40430366e-11f, 5.55021075e-08f, -1.98503712e-04f, 2.89312858e-02f},
+ {-1.40949732e-11f, 1.89878968e-07f, -3.56632824e-04f, 9.10767778e-02f},
+ {-3.61460868e-11f, 2.84822009e-07f, -4.93211319e-04f, 1.56723440e-01f},
+ {-1.97075738e-11f, 1.75359352e-07f, -2.50542825e-04f, -2.22783266e-02f},
+ {-1.61997957e-13f, -1.64216008e-08f, 3.86216271e-04f, -7.38077418e-01f},
+ {6.72650283e-13f, -2.73078809e-08f, 4.24098264e-04f, -7.52335691e-01f}
 };
 
 ccl_inline_constant float cie_colour_match[][3] = {
diff --git a/intern/cycles/scene/shader_nodes.cpp b/intern/cycles/scene/shader_nodes.cpp
index 03c152928d5..3b58556f601 100644
--- a/intern/cycles/scene/shader_nodes.cpp
+++ b/intern/cycles/scene/shader_nodes.cpp
@@ -5882,7 +5882,7 @@ void BlackbodyNode::constant_fold(const ConstantFolder &folder)
   if (folder.all_inputs_constant()) {
     const float3 rgb_rec709 = svm_math_blackbody_color_rec709(temperature);
     const float3 rgb = folder.scene->shader_manager->rec709_to_scene_linear(rgb_rec709);
-    folder.make_constant(rgb);
+    folder.make_constant(max(rgb, zero_float3()));
   }
 }
 
diff --git a/intern/cycles/test/render_graph_finalize_test.cpp b/intern/cycles/test/render_graph_finalize_test.cpp
index 143628f1e30..dac36ab0135 100644
--- a/intern/cycles/test/render_graph_finalize_test.cpp
+++ b/intern/cycles/test/render_graph_finalize_test.cpp
@@ -946,7 +946,7 @@ TEST_F(RenderGraph, constant_fold_bright_contrast)
 TEST_F(RenderGraph, constant_fold_blackbody)
 {
   EXPECT_ANY_MESSAGE(log);
-  CORRECT_INFO_MESSAGE(log, "Folding Blackbody::Color to constant (3.94163, 0.226523, 0).");
+  CORRECT_INFO_MESSAGE(log, "Folding Blackbody::Color to constant (3.96553, 0.227897, 0).");
 
   builder
       .add_node(ShaderNodeBuilder<BlackbodyNode>(graph, "Blackbody").set("Temperature", 1200.0f))