{
m_trace = trace;
double start_angle = (iStartView + iOffsetView) * proj.rotInc();
+ int parallel_enabled = 1;
+ UNUSED(parallel_enabled);
-#ifdef HAVE_OPENMP
- #pragma omp parallel for
+#if HAVE_SGP
+ if (pSGP && (m_trace >= Trace::TRACE_PHANTOM))
+ parallel_enabled = 0;
#endif
+#if HAVE_OPENMP
+ #pragma omp parallel for if (parallel_enabled)
+#endif
for (int iView = 0; iView < iNumViews; iView++) {
double viewAngle = start_angle + (iView * proj.rotInc());
}
}
+void swap_xy_points (double& x1, double& y1, double& x2, double& y2)
+{
+ double temp = x1; x1 = x2; x2 = temp;
+ temp = y1; y1 = y2; y2 = temp;
+}
+
+class WeightedPoint {
+public:
+ int x, y;
+ double weight;
+ WeightedPoint (int _x, int _y, double _weight)
+ : x(_x), y(_y), weight(_weight)
+ {}
+};
+
+
+/* FUNCTION
+ * Name: projection_pixel_weights
+ * Purpose: Returns a vector of WeightedPoint with the length of
+ * line that intersects with each pixel
+ */
+
+void
+projection_pixel_weights (std::vector<WeightedPoint>& wp, const int nx, const int ny,
+ double x1, double y1, double x2, double y2)
+{
+ double ylen = fabs(y2-y1);
+ double xlen = fabs(x2-x1);
+ bool swap_xy = false, invert_slope = false;
+ double slope;
+
+ if (ylen > xlen) {
+ swap_xy = true;
+ slope = xlen / ylen;
+ if (y2 < y1) // swap start/end so always moving from bottom to top
+ swap_xy_points (x1, y1, x2, y2);
+ if (x2 < x1) {
+ invert_slope = true;
+ }
+ } else {
+#if DEBUG
+ if (ylen == xlen)
+ sys_error(ERR_WARNING, "Slope == 1");
+#endif
+ slope = ylen / xlen;
+ if (x2 < x1) // swap start/end so always moving from left to right in image
+ swap_xy_points (x1, y1, x2, y2);
+ if (y2 < y1) {
+ invert_slope = true;
+ }
+ }
+ double angle = atan(fabs(slope));
+ double minor_dist = sin(angle); // distance along minor axis
+ double pixel_len = 1 / cos(angle);
+
+ int minor_dir = 1;
+ if (invert_slope) {
+ minor_dir = -1;
+ slope = -slope;
+ }
+
+ double x = x1, y = y1;
+ int ix = floor(x);
+ int iy = floor(y);
+ double ydelta = y - iy;
+ double xdelta = x - ix;
+
+ double min_delta;
+ int *imaj, *imin;
+ int max_maj, max_min;
+ if (swap_xy) {
+ min_delta = xdelta;
+ imaj = &iy;
+ imin = &ix;
+ max_maj = ny;
+ max_min = nx;
+ } else {
+ min_delta = ydelta;
+ imaj = &ix;
+ imin = &iy;
+ max_maj = nx;
+ max_min = ny;
+ }
+
+#if DEBUG
+ sys_error(ERR_TRACE, "m=%6.3f swap_xy=%d invert=%d len=%8.6f min_delta=%.4g minor_dist=%6.3f (%.3f,%.3f)-(%.3f,%.3f)",
+ slope, swap_xy, invert_slope, pixel_len, min_delta, minor_dist, x1, y1, x2, y2);
+#endif
+
+ // if position of minor axis is at edge of image, but will be moving into pixel within image
+ if (*imin == max_min && invert_slope) {
+ (*imin)--; // select the pixel within image
+#if DEBUG
+ sys_error(ERR_TRACE, "Moving pixel inside image, adding %f to min_delta", (1+slope));
+#endif
+ min_delta += (1+slope);
+ }
+
+ while (*imaj < max_maj && *imin < max_min && *imin >= 0) {
+ double next_min_delta = min_delta + slope;
+
+ if (((!invert_slope) && (next_min_delta < 1)) ||
+ (invert_slope && (next_min_delta > 0))) {
+ // stay within same pixel
+ double w = pixel_len;
+ WeightedPoint p (ix, iy, w);
+ wp.push_back(p);
+#if DEBUG
+ sys_error(ERR_TRACE, " Full pixel: (%3d,%3d)=%.4g, min_delta=%.4g", ix, iy, w, min_delta);
+#endif
+ min_delta = next_min_delta;
+ } else {
+ // Scale partial pixel_len into pixel
+ double norm_delta = invert_slope ? min_delta : (1 - min_delta);
+ double p1_line = norm_delta * pixel_len;
+ WeightedPoint p1 (ix, iy, p1_line);
+ wp.push_back (p1);
+#if DEBUG
+ sys_error(ERR_TRACE, " Part pixel: (%3d,%3d)=%.4g, min_delta=%.4g", ix, iy, p1_line, min_delta);
+#endif
+ (*imin) += minor_dir;
+ min_delta = next_min_delta - minor_dir;
+ }
+ (*imaj)++;
+ }
+
+}
/* NAME
const ImageFile* im = phm.getImagefile();
const ImageFileArray v = im->getArray();
- int nx = im->nx(), ny = im->ny();
- // Convert endpoints into image pixel coordinates
+ // Get image axis extents
+ int nx = im->nx(), ny = im->ny();
double xmin=0, xmax=nx, ymin=0, ymax=ny; // default coordinate
if (! im->getAxisExtent (xmin, xmax, ymin, ymax)) {
sys_error(ERR_WARNING, "Axis extent not available [Scanner::projectSingleLine]");
}
+
+ // Clip line in image object coordinates
double rect[4];
rect[0] = xmin; rect[1] = ymin;
- rect[2] = xmax; rect[3] = ymax;
+ rect[2] = xmax; rect[3] = ymax;
bool accept = clip_rect (x1, y1, x2, y2, rect);
if (! accept)
return (0.0);
- double xlen = xmax - xmin, ylen = ymax - ymin;
+ // Convert to pixel coordinates
+ double xlen = xmax - xmin;
+ double ylen = ymax - ymin;
double px1 = nx * (x1 - xmin) / xlen;
double px2 = nx * (x2 - xmin) / xlen;
double py1 = ny * (y1 - ymin) / ylen;
double py2 = ny * (y2 - ymin) / ylen;
- // Use Bresenham integer line stepping to step to each pixel, and walked through image
-
- sys_error(ERR_WARNING, "Not yet able to project through imagefile. Line (%.3f,%.3f) - (%.3f,%.3f)", px1, py1, px2, py2);
-
+ std::vector<WeightedPoint> wp;
+ projection_pixel_weights (wp, nx, ny, px1, py1, px2, py2);
+ for (unsigned int i = 0; i < wp.size(); i++) {
+ WeightedPoint& p = wp[i];
+ rsum += v[p.x][p.y] * p.weight;
+ }
} else {
// Project through each pelem in Phantom
projects / ctsim.git / blobdiff