Add a scale bar to the diffraction patterns

3 files changed, 47 insertions, 0 deletions

diff --git a/src/imagedisplay.c b/src/imagedisplay.c
index 4ca46a5..b6de26a 100644
--- a/src/imagedisplay.c
+++ b/src/imagedisplay.c
@@ -23,6 +23,7 @@
 
 #include "imagedisplay.h"
 #include "utils.h"
+#include "mapping.h"
 
 /* Free pixbuf data when reference count drops to zero */
 static void imagedisplay_free_data(guchar *image_eightbit, ImageDisplay *imagedisplay) {
@@ -167,6 +168,33 @@ void imagedisplay_close(ImageDisplay *imagedisplay) {
 	}
 }
 
+static void imagedisplay_add_scalebar(ImageDisplay *imagedisplay, GtkWidget *drawingarea,
+							double scale, double xoffs, double yoffs) {
+
+	PangoLayout *layout;
+	double sb;
+	PangoRectangle rect;
+	int bwidth, bheight;
+	int view_height = imagedisplay->view_height;
+	
+	sb = mapping_scale_bar_length(&imagedisplay->imagerecord);
+	layout = gtk_widget_create_pango_layout(drawingarea, "1 nm^-1");
+	pango_layout_get_pixel_extents(layout, &rect, NULL);
+	
+	bwidth = (sb*scale)+20;
+	bheight = rect.height+30;
+	if ( rect.width > bwidth ) bwidth = rect.width+20;
+	gdk_draw_rectangle(drawingarea->window, drawingarea->style->bg_gc[GTK_WIDGET_STATE(drawingarea)], TRUE,
+				xoffs+20, yoffs+view_height-20-bheight,
+				bwidth, bheight);
+	gdk_draw_line(drawingarea->window, drawingarea->style->fg_gc[GTK_WIDGET_STATE(drawingarea)],
+				xoffs+30, yoffs+view_height-30,
+				xoffs+30+(scale*sb), yoffs+view_height-30);
+	gdk_draw_layout(drawingarea->window, drawingarea->style->fg_gc[GTK_WIDGET_STATE(drawingarea)],
+				xoffs+30, yoffs+view_height-20-bheight+10, layout);
+
+}
+
 #define imagedisplay_draw_line(gc,x1,y1,x2,y2) (gdk_draw_line(drawingarea->window,gc, \
 						xoffs+(x1), yoffs+imagedisplay->view_height-1-(y1), \
 						xoffs+(x2), yoffs+imagedisplay->view_height-1-(y2)))
@@ -202,6 +230,9 @@ static gboolean imagedisplay_redraw(GtkWidget *drawingarea, GdkEventExpose *even
 					* tan(imagedisplay->imagerecord.omega)) * scale);
 	}
 	
+	/* Add scale bar */
+	imagedisplay_add_scalebar(imagedisplay, drawingarea, scale, xoffs, yoffs);
+	
 	/* NB This calls the function above, which sorts out stuff */
 	if ( imagedisplay->flags & IMAGEDISPLAY_SHOW_CENTRE ) {
 		imagedisplay_draw_line(imagedisplay->gc_centre,
diff --git a/src/mapping.c b/src/mapping.c
index 54a7235..4897450 100644
--- a/src/mapping.c
+++ b/src/mapping.c
@@ -128,6 +128,20 @@ int mapping_scale(ImageFeature *refl, double *ddx, double *ddy) {
 	
 }
 
+/* Return the length of a 1 nm^-1 scale bar in the given image (in pixels)
+ *  Result only strictly valid at the centre of the image */
+double mapping_scale_bar_length(ImageRecord *image) {
+
+	switch ( image->fmode ) {
+		case FORMULATION_PIXELSIZE : return 1.0e9/image->pixel_size;
+		case FORMULATION_CLEN : return image->camera_len*image->lambda;
+		default : fprintf(stderr, "Unrecognised formulation mode in mapping_scale_bar_length.\n");
+	}
+	
+	return 0.0;
+
+}
+
 void mapping_map_features(ControlContext *ctx) {
 
 	int i;
diff --git a/src/mapping.h b/src/mapping.h
index 6724499..82d2f04 100644
--- a/src/mapping.h
+++ b/src/mapping.h
@@ -18,11 +18,13 @@
 
 #include "reflections.h"
 #include "control.h"
+#include "image.h"
 
 extern void mapping_rotate(double x, double y, double z, double *ddx, double *ddy, double *ddz,
 			   double omega, double tilt);
 extern int mapping_map_to_space(ImageFeature *refl, double *ddx, double *ddy, double *ddz, double *twotheta);
 extern int mapping_scale(ImageFeature *refl, double *ddx, double *ddy);
+extern double mapping_scale_bar_length(ImageRecord *image);
 
 extern void mapping_adjust_axis(ControlContext *ctx, double offset);
 extern void mapping_map_features(ControlContext *ctx);