htrdr

commit db50d7467f11d45a20c61cc8473c4dc1ab9dc277
parent fec112abc16950412ad6386b8be9fe78bdaac916
Author: Vincent Forest <vincent.forest@meso-star.com>
Date:   Fri, 12 Mar 2021 15:25:14 +0100

Update the unit of the pdf returned by htrdr_ran_wlen_sample

Diffstat:
M
src/atmosphere/htrdr_atmosphere_draw_map.c
 | 
4
+++-
M
src/core/htrdr_ran_wlen.c
 | 
5
+++--
M
src/core/htrdr_ran_wlen.h
 | 
2
+-

3 files changed, 7 insertions(+), 4 deletions(-)
diff --git a/src/atmosphere/htrdr_atmosphere_draw_map.c b/src/atmosphere/htrdr_atmosphere_draw_map.c
@@ -165,6 +165,7 @@ draw_pixel_image
         case 2: wlen = htrdr_cie_xyz_sample_Z(cmd->cie, r0, r1, &pdf); break;
         default: FATAL("Unreachable code.\n"); break;
       }
+      pdf *= 1.e9; /* Transform the pdf from nm^-1 to m^-1 */
 
       iband = htsky_find_spectral_band(cmd->sky, wlen);
       iquad = htsky_spectral_band_sample_quadrature(cmd->sky, r2, iband);
@@ -174,7 +175,6 @@ draw_pixel_image
         ATMOSPHERE_RADIANCE_ALL, ray_org, ray_dir, wlen, iband, iquad);
       ASSERT(weight >= 0);
 
-      pdf *= 1.e9; /* Transform the pdf from nm^-1 to m^-1 */
       weight /= pdf; /* In W/m^2/sr */
 
       /* End the registration of the per realisation time */
@@ -250,6 +250,7 @@ draw_pixel_flux
 
     /* Sample a wavelength */
     wlen = htrdr_ran_wlen_sample(cmd->ran_wlen, r0, r1, &band_pdf);
+    band_pdf *= 1.e9; /* Transform the pdf from nm^-1 to m^-1 */
 
     /* Select the associated band and sample a quadrature point */
     iband = htsky_find_spectral_band(cmd->sky, wlen);
@@ -370,6 +371,7 @@ draw_pixel_xwave
 
     /* Sample a wavelength */
     wlen = htrdr_ran_wlen_sample(cmd->ran_wlen, r0, r1, &band_pdf);
+    band_pdf *= 1.e9; /* Transform the pdf from nm^-1 to m^-1 */
 
     /* Select the associated band and sample a quadrature point */
     iband = htsky_find_spectral_band(cmd->sky, wlen);
diff --git a/src/core/htrdr_ran_wlen.c b/src/core/htrdr_ran_wlen.c
@@ -201,9 +201,10 @@ wlen_ran_sample_continue
     const double B_lambda = htrdr_planck(lambda_m, lambda_m, Tref);
     const double B_mean = htrdr_planck(range_m[0], range_m[1], Tref);
     *pdf = B_lambda / (B_mean * (range_m[1]-range_m[0]));
+    *pdf = 1.e-9; /* Transform from m^-1 to nm^-1 */
   }
 
-  return lambda_m * 1.0e9; /* Convert in nanometers */
+  return lambda_m * 1.e9; /* Convert in nanometers */
 }
 
 static double
@@ -249,7 +250,7 @@ wlen_ran_sample_discrete
 
   /* Uniformly sample a wavelength in the sampled band */
   lambda = band_range[0] + (band_range[1] - band_range[0]) * r1;
-  pdf_continue = 1.0 / ((band_range[1] - band_range[0])*1.e-9);
+  pdf_continue = 1.0 / (band_range[1] - band_range[0]);
 
   if(pdf) {
     *pdf = pdf_band * pdf_continue;
diff --git a/src/core/htrdr_ran_wlen.h b/src/core/htrdr_ran_wlen.h
@@ -53,7 +53,7 @@ htrdr_ran_wlen_sample
   (const struct htrdr_ran_wlen* wlen_ran,
    const double r0, /* Canonical number in [0, 1[ */
    const double r1, /* Canonical number in [0, 1[ */
-   double* pdf); /* May be NULL */
+   double* pdf); /* In nm^-1. May be NULL */
 
 END_DECLS