diff options
Diffstat (limited to 'intern/cycles/kernel/svm/svm_math_util.h')
| -rw-r--r-- | intern/cycles/kernel/svm/svm_math_util.h | 64 |
1 files changed, 63 insertions, 1 deletions
diff --git a/intern/cycles/kernel/svm/svm_math_util.h b/intern/cycles/kernel/svm/svm_math_util.h index 39cc14d5e8e..645cbd3fc73 100644 --- a/intern/cycles/kernel/svm/svm_math_util.h +++ b/intern/cycles/kernel/svm/svm_math_util.h @@ -97,12 +97,74 @@ ccl_device float svm_math(NodeMath type, float Fac1, float Fac2) else if(type == NODE_MATH_ABSOLUTE) Fac = fabsf(Fac1); else if(type == NODE_MATH_CLAMP) - Fac = clamp(Fac1, 0.0f, 1.0f); + Fac = saturate(Fac1); else Fac = 0.0f; return Fac; } +ccl_device float3 svm_math_blackbody_color(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. + */ + + const float rc[6][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 }, + }; + + const float gc[6][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 }, + }; + + const float bc[6][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 }, + }; + + if(t >= 12000.0f) + return make_float3(0.826270103f, 0.994478524f, 1.56626022f); + + /* Define a macro to reduce stack usage for nvcc */ +#define MAKE_BB_RGB(i) make_float3(\ + rc[i][0] / t + rc[i][1] * t + rc[i][2],\ + gc[i][0] / t + gc[i][1] * t + gc[i][2],\ + ((bc[i][0] * t + bc[i][1]) * t + bc[i][2]) * t + bc[i][3]) + + if(t >= 6365.0f) + return MAKE_BB_RGB(5); + if(t >= 3315.0f) + return MAKE_BB_RGB(4); + if(t >= 1902.0f) + return MAKE_BB_RGB(3); + if(t >= 1449.0f) + return MAKE_BB_RGB(2); + if(t >= 1167.0f) + return MAKE_BB_RGB(1); + if(t >= 965.0f) + return MAKE_BB_RGB(0); + +#undef MAKE_BB_RGB + + /* 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); +} + CCL_NAMESPACE_END |