commit cd9255ceecefacde912d4ba328b693dd7214dbb8
parent 5d364a387620ef412c36de7e1ee90d510c3ab9db
Author: Vincent Forest <vincent.forest@meso-star.com>
Date: Thu, 25 Mar 2021 15:02:59 +0100
Review the code of the combustion_compute_radiance_sw function
Diffstat:
2 files changed, 21 insertions(+), 17 deletions(-)
diff --git a/src/combustion/htrdr_combustion_args.h b/src/combustion/htrdr_combustion_args.h
@@ -93,7 +93,7 @@ struct htrdr_combustion_args {
\
HTRDR_ARGS_RECTANGLE_DEFAULT__, /* Laser surface emission */ \
532, /* Wavelength in nanometer */ \
- 1, /* FIXME Flux density */ \
+ 1, /* Flux density */ \
\
HTRDR_ARGS_IMAGE_DEFAULT__, /* Image */ \
\
diff --git a/src/combustion/htrdr_combustion_compute_radiance_sw.c b/src/combustion/htrdr_combustion_compute_radiance_sw.c
@@ -46,8 +46,10 @@ static const struct position POSITION_NULL = POSITION_NULL__;
/* Syntactic sugar to check if the position is valid */
#define POSITION_NONE(Pos) ((Pos)->distance >= DBL_MAX)
-/* Common position but preferentially sampled within a limited range.
- * Its associated ksi variable defines ??? TODO write the comment */
+/* Common position but preferentially sampled within a limited range. Its
+ * associated ksi variable defines the correction of the weight due to the
+ * normalization of the sampling pdf, and the recursivity associated with the
+ * null-collision technique. */
struct position_limited {
struct position position;
double ksi;
@@ -554,13 +556,16 @@ laser_once_scattered
(cmd->laser, xsc);
ASSERT(range[1] >= 0);
Tr_ext_xsc_lse = transmissivity(cmd, rng, ATRSTM_RADCOEF_Kext, xsc, wi, range);
- if(Tr_ext_xsc_lse == 0) return 0; /* No aser contribution */
+ if(Tr_ext_xsc_lse == 0) return 0; /* No laser contribution */
/* Retrieve the RDG-FA phase function parameters from the semi transparent
* medium */
fetch_rdgfa_args.wavelength = wlen;
fetch_rdgfa_args.prim = sc_sample.position.prim;
- d4_set(fetch_rdgfa_args.bcoords, sc_sample.position.bcoords);
+ fetch_rdgfa_args.bcoords[0] = sc_sample.position.bcoords[0];
+ fetch_rdgfa_args.bcoords[1] = sc_sample.position.bcoords[1];
+ fetch_rdgfa_args.bcoords[2] = sc_sample.position.bcoords[2];
+ fetch_rdgfa_args.bcoords[3] = sc_sample.position.bcoords[3];
ATRSTM(fetch_rdgfa(cmd->medium, &fetch_rdgfa_args, &rdgfa_param));
/* Setup the RDG-FA phase function */
@@ -603,8 +608,8 @@ combustion_compute_radiance_sw
SSF_PHASE_RDGFA_SETUP_ARGS_DEFAULT;
struct ssf_phase* rdgfa = NULL;
- /* Transmissivity due to absorption between two consecutive scattering
- * positions */
+ /* Transmissivity between the probe position (i.e. 'pos_in') and the current
+ * scattering position over the reverse scattering path */
double Tr_abs = 1;
/* Monte carlo weight of the simulated optical path */
@@ -648,6 +653,14 @@ combustion_compute_radiance_sw
Tr_abs_pos_xsc = transmissivity(cmd, rng, ATRSTM_RADCOEF_Ka, pos, dir, range);
if(Tr_abs_pos_xsc == 0) break;
+ /* Update the overall absorption transmissivity of the optical path */
+ Tr_abs *= Tr_abs_pos_xsc;
+
+ /* Update the position of the optical path */
+ pos[0] = pos[0] + dir[0] * scattering.distance;
+ pos[1] = pos[1] + dir[1] * scattering.distance;
+ pos[2] = pos[2] + dir[2] * scattering.distance;
+
/* Retrieve the RDG-FA phase function parameters */
fetch_rdgfa_args.wavelength = wlen;
fetch_rdgfa_args.prim = scattering.prim;
@@ -667,19 +680,10 @@ combustion_compute_radiance_sw
d3_minus(wo, dir); /* Ensure SSF convention */
ssf_phase_sample(rdgfa, rng, wo, wi, NULL);
- /* Update the overall absorption transmissivity of the optical path and its
- * Monte-Carlo weight */
- Tr_abs *= Tr_abs_pos_xsc;
- weight *= Tr_abs;
-
- /* Update the position and direction of the optical path */
- pos[0] = pos[0] + dir[0] * scattering.distance;
- pos[1] = pos[1] + dir[1] * scattering.distance;
- pos[2] = pos[2] + dir[2] * scattering.distance;
+ /* Update the optical path direction */
dir[0] = wi[0];
dir[1] = wi[1];
dir[2] = wi[2];
}
return weight;
}
-
