Add "bandwidth" to beam parameters file

Also, fix previous commit.

6 files changed, 34 insertions, 14 deletions

diff --git a/doc/examples/lcls-dec.beam b/doc/examples/lcls-dec.beam
index e19709a3..5fe6ea24 100644
--- a/doc/examples/lcls-dec.beam
+++ b/doc/examples/lcls-dec.beam
@@ -7,6 +7,11 @@ beam/radius = 3.0e-6 / 2.0
 ; Photon energy in eV
 beam/photon_energy = 2000.0
 
+; Bandwidth: FWHM(wavelength) over wavelength.
+; Note: current simulation code just uses a rectangular
+;       distribution with this as its (full) width.
+beam/bandwidth = 0.001
+
 
 ; Detector's quantum efficiency
 detector/dqe = 0.9
diff --git a/doc/examples/lcls-june.beam b/doc/examples/lcls-june.beam
index cc6cf28f..367e9921 100644
--- a/doc/examples/lcls-june.beam
+++ b/doc/examples/lcls-june.beam
@@ -7,6 +7,11 @@ beam/radius = 3.0e-6 / 2.0
 ; Photon energy in eV
 beam/photon_energy = 2000.0
 
+; Bandwidth: FWHM(wavelength) over wavelength.
+; Note: current simulation code just uses a rectangular
+;       distribution with this as its (full) width.
+beam/bandwidth = 0.001
+
 
 ; Detector's quantum efficiency
 detector/dqe = 0.9
diff --git a/src/beam-parameters.c b/src/beam-parameters.c
index 73dc2897..9f5a0dde 100644
--- a/src/beam-parameters.c
+++ b/src/beam-parameters.c
@@ -37,6 +37,7 @@ struct beam_params *get_beam_parameters(const char *filename)
 	b->fluence = -1.0;
 	b->beam_radius = -1.0;
 	b->photon_energy = -1.0;
+	b->bandwidth = -1.0;
 	b->dqe = -1.0;
 	b->adu_per_photon = -1.0;
 	b->water_radius = -1.0;
@@ -66,17 +67,19 @@ struct beam_params *get_beam_parameters(const char *filename)
 		}
 
 		if ( strcmp(bits[0], "beam/fluence") == 0 ) {
-			b->fluence = atof(bits[0]);
+			b->fluence = atof(bits[2]);
 		} else if ( strcmp(bits[0], "beam/radius") == 0 ) {
-			b->beam_radius = atof(bits[0]);
+			b->beam_radius = atof(bits[2]);
 		} else if ( strcmp(bits[0], "beam/photon_energy") == 0 ) {
-			b->photon_energy = atof(bits[0]);
+			b->photon_energy = atof(bits[2]);
+		} else if ( strcmp(bits[0], "beam/bandwidth") == 0 ) {
+			b->bandwidth = atof(bits[2]);
 		} else if ( strcmp(bits[0], "detector/dqe") == 0 ) {
-			b->dqe = atof(bits[0]);
+			b->dqe = atof(bits[2]);
 		} else if ( strcmp(bits[0], "detector/adu_per_photon") == 0 ) {
-			b->adu_per_photon = atof(bits[0]);
+			b->adu_per_photon = atof(bits[2]);
 		} else if ( strcmp(bits[0], "jet/radius") == 0 ) {
-			b->water_radius = atof(bits[0]);
+			b->water_radius = atof(bits[2]);
 		} else {
 			ERROR("Unrecognised field '%s'\n", bits[0]);
 		}
@@ -102,6 +105,10 @@ struct beam_params *get_beam_parameters(const char *filename)
 		      " 'beam/photon_energy'.\n");
 		reject = 1;
 	}
+	if ( b->bandwidth < 0.0 ) {
+		ERROR("Invalid or unspecified value for 'beam/bandwidth'.\n");
+		reject = 1;
+	}
 	if ( b->dqe < 0.0 ) {
 		ERROR("Invalid or unspecified value for 'detector/dqe'.\n");
 		reject = 1;
diff --git a/src/beam-parameters.h b/src/beam-parameters.h
index 84d95b49..aec2c6aa 100644
--- a/src/beam-parameters.h
+++ b/src/beam-parameters.h
@@ -23,6 +23,10 @@ struct beam_params
 	double fluence;        /* photons per pulse */
 	double beam_radius;    /* metres */
 	double photon_energy;  /* eV per photon */
+	double bandwidth;      /* FWHM(wavelength) over wavelength.
+	                        *  Note: current simulation code just uses
+	                        *        a rectangular distribution with this as
+	                        *        its (full) width. */
 
 	double dqe;            /* Detector DQE (fraction) */
 	double adu_per_photon; /* Detector "gain" */
diff --git a/src/diffraction-gpu.c b/src/diffraction-gpu.c
index 7a5bef85..409178b9 100644
--- a/src/diffraction-gpu.c
+++ b/src/diffraction-gpu.c
@@ -23,11 +23,11 @@
 #include "diffraction.h"
 #include "sfac.h"
 #include "cl-utils.h"
+#include "beam-parameters.h"
 
 
 #define SAMPLING (4)
-#define BWSAMPLING (1)
-#define BANDWIDTH (0.0 / 100.0)
+#define BWSAMPLING (10)
 
 #define SINC_LUT_ELEMENTS (4096)
 
@@ -137,8 +137,8 @@ void get_diffraction_gpu(struct gpu_context *gctx, struct image *image,
 
 	/* Calculate wavelength */
 	k = 1.0/image->lambda;  /* Centre value */
-	klow = k - k*(BANDWIDTH/2.0);  /* Lower value */
-	bwstep = k * BANDWIDTH / BWSAMPLING;
+	klow = k - k*(image->beam->bandwidth/2.0);  /* Lower value */
+	bwstep = k * image->beam->bandwidth / BWSAMPLING;
 
 	/* Orientation */
 	orientation.s[0] = image->orientation.w;
diff --git a/src/diffraction.c b/src/diffraction.c
index 00a73b94..66a2ba27 100644
--- a/src/diffraction.c
+++ b/src/diffraction.c
@@ -26,8 +26,7 @@
 
 
 #define SAMPLING (4)
-#define BWSAMPLING (1)
-#define BANDWIDTH (0.0 / 100.0)
+#define BWSAMPLING (10)
 
 
 static double lattice_factor(struct rvec q, double ax, double ay, double az,
@@ -313,8 +312,8 @@ void get_diffraction(struct image *image, int na, int nb, int nc,
 	image->twotheta = malloc(image->width * image->height * sizeof(double));
 
 	k = 1.0/image->lambda;  /* Centre value */
-	klow = k - k*(BANDWIDTH/2.0);  /* Lower value */
-	bwstep = k * BANDWIDTH / BWSAMPLING;
+	klow = k - k*(image->beam->bandwidth/2.0);  /* Lower value */
+	bwstep = k * image->beam->bandwidth / BWSAMPLING;
 
 	for ( xs=0; xs<image->width*SAMPLING; xs++ ) {
 	for ( ys=0; ys<image->height*SAMPLING; ys++ ) {