diff options
author | Thomas White <taw@physics.org> | 2009-11-19 19:26:56 +0100 |
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committer | Thomas White <taw@physics.org> | 2009-11-19 19:26:56 +0100 |
commit | da1167955e843460414cc6caa2af0979f36caf4c (patch) | |
tree | 6db15ed6e64f327b9520770b828af4d41389f9ce /src | |
parent | 377810c338e2f84d0ebc4b44086eb8ecf5f6741d (diff) |
Add rotation based on quaternions
Diffstat (limited to 'src')
-rw-r--r-- | src/ewald.c | 40 | ||||
-rw-r--r-- | src/image.h | 15 | ||||
-rw-r--r-- | src/main.c | 50 |
3 files changed, 91 insertions, 14 deletions
diff --git a/src/ewald.c b/src/ewald.c index 02974175..7a620c42 100644 --- a/src/ewald.c +++ b/src/ewald.c @@ -20,6 +20,37 @@ #include "ewald.h" +static struct threevec quat_rot(struct threevec q, struct quaternion z) +{ + struct threevec res; + double t01, t02, t03, t11, t12, t13, t22, t23, t33; + + t01 = z.w*z.x; + t02 = z.w*z.y; + t03 = z.w*z.z; + t11 = z.x*z.x; + t12 = z.x*z.y; + t13 = z.x*z.z; + t22 = z.y*z.y; + t23 = z.y*z.z; + t33 = z.z*z.z; + + res.u = (1.0 - 2.0 * (t22 + t33)) * q.u + + (2.0 * (t12 + t03)) * q.v + + (2.0 * (t13 - t02)) * q.w; + + res.v = (2.0 * (t12 - t03)) * q.u + + (1.0 - 2.0 * (t11 + t33)) * q.v + + (2.0 * (t01 + t23)) * q.w; + + res.w = (2.0 * (t02 + t13)) * q.u + + (2.0 * (t23 - t01)) * q.v + + (1.0 - 2.0 * (t11 + t22)) * q.w; + + return res; +} + + void get_ewald(struct image *image) { int x, y; @@ -39,6 +70,7 @@ void get_ewald(struct image *image) double rx, ry, r; double twothetax, twothetay, twotheta; double qx, qy, qz; + struct threevec q; /* Calculate q vectors for Ewald sphere */ rx = ((double)x - image->x_centre) / image->resolution; @@ -52,9 +84,11 @@ void get_ewald(struct image *image) qx = k * sin(twothetax); qy = k * sin(twothetay); qz = k - k * cos(twotheta); - - /* FIXME: Rotate vector here */ - + + q.u = qx; q.v = qy; q.w = qz; + image->qvecs[x + image->width*y] = quat_rot(q, + image->orientation); + image->qvecs[x + image->width*y].u = qx; image->qvecs[x + image->width*y].v = qy; image->qvecs[x + image->width*y].w = qz; diff --git a/src/image.h b/src/image.h index b40f8a57..5206048a 100644 --- a/src/image.h +++ b/src/image.h @@ -57,6 +57,15 @@ struct threevec }; +struct quaternion +{ + double w; + double x; + double y; + double z; +}; + + /* Structure describing an image */ struct image { @@ -67,11 +76,7 @@ struct image { double *twotheta; struct molecule *molecule; - /* Radians. Defines where the pattern lies in reciprocal space */ - double tilt; - - /* Radians. Defines where the pattern lies in reciprocal space */ - double omega; + struct quaternion orientation; /* Image parameters can be given as camera length or pixel size. * If FORMULATION_CLEN, then camera_len and resolution must be given. @@ -40,9 +40,11 @@ static void main_show_help(const char *s) int main(int argc, char *argv[]) { - int c; + int c, done; UnitCell *cell; struct image image; + char filename[1024]; + int number = 1; while ((c = getopt(argc, argv, "h")) != -1) { @@ -65,11 +67,44 @@ int main(int argc, char *argv[]) deg2rad(90.0), deg2rad(120.0)); +again: + + /* Read quaternion from stdin */ + done = 0; + do { + + int r; + float w, x, y, z; + char line[1024]; + char *rval; + + printf("Please input quaternion: w x y z\n"); + rval = fgets(line, 1023, stdin); + if ( rval == NULL ) return 0; + chomp(line); + + r = sscanf(line, "%f %f %f %f", &w, &x, &y, &z); + if ( r == 4 ) { + + printf("Rotation is: %f %f %f %f (modulus=%f)\n", + w, x, y, z, sqrtf(w*w + x*x + y*y + z*z)); + + image.orientation.w = w; + image.orientation.x = x; + image.orientation.y = y; + image.orientation.z = z; + + done = 1; + + } else { + fprintf(stderr, "Invalid rotation '%s'\n", line); + } + + } while ( !done ); + /* Define image parameters */ image.width = 512; image.height = 512; - image.omega = deg2rad(40.0); - image.tilt = deg2rad(0.0); image.fmode = FORMULATION_CLEN; image.x_centre = 255.5; image.y_centre = 255.5; @@ -88,8 +123,11 @@ int main(int argc, char *argv[]) get_diffraction(&image, cell); record_image(&image); - /* Write the output file */ - hdf5_write("results/sim.h5", image.data, image.width, image.height); + snprintf(filename, 1023, "results/sim-%i.h5", number); + number++; - return 0; + /* Write the output file */ + hdf5_write(filename, image.data, image.width, image.height); + printf("Mock write: %i\n", number-1); + goto again; } |