[gthumb: 107/129] rotate tool: removed center of rotation, has no meaning here

[Paolo Bacchilega <paobac src gnome org>]

commit 58be15fbb002df73f24e4e854f347c47366ee940
Author: Stefano Pettini <spettini users sourceforge net>
Date:   Thu Apr 21 15:21:55 2011 +0100

    rotate tool: removed center of rotation, has no meaning here

 extensions/file_tools/gdk-pixbuf-rotate.c    |   36 ++++++++++----------------
 extensions/file_tools/gdk-pixbuf-rotate.h    |    2 -
 extensions/file_tools/gth-file-tool-rotate.c |    6 +---
 3 files changed, 15 insertions(+), 29 deletions(-)
---
diff --git a/extensions/file_tools/gdk-pixbuf-rotate.c b/extensions/file_tools/gdk-pixbuf-rotate.c
index ca72662..c9dffd7 100644
--- a/extensions/file_tools/gdk-pixbuf-rotate.c
+++ b/extensions/file_tools/gdk-pixbuf-rotate.c
@@ -26,8 +26,6 @@
 
 static GdkPixbuf*
 rotate (GdkPixbuf *src_pixbuf,
-	double     center_x,
-	double     center_y,
 	double     angle,
 	gint       auto_crop)
 {
@@ -35,7 +33,6 @@ rotate (GdkPixbuf *src_pixbuf,
 
 	double     angle_rad;
 	double     cos_angle, sin_angle;
-	double     center_dx, center_dy;
 	int        src_width, src_height;
 	int        new_width, new_height;
 	int        src_rowstride, new_rowstride;
@@ -45,15 +42,12 @@ rotate (GdkPixbuf *src_pixbuf,
 	double     x2, y2;
 	int        x2i, y2i;
 	guchar    *p_src, *p_new;
-	guchar    *p_src2, *p_new_row;
+	guchar    *p_src2, *p_new2;
 	
 	angle_rad = angle / 180.0 * 3.1415926535;
 	
 	cos_angle = cos (angle_rad);
 	sin_angle = sin (angle_rad);
-	
-	center_dx =      cos_angle  * center_x + fabs(sin_angle) * center_y;
-	center_dy = fabs(sin_angle) * center_x +      cos_angle  * center_y;
 
 	src_width  = gdk_pixbuf_get_width  (src_pixbuf);
 	src_height = gdk_pixbuf_get_height (src_pixbuf);
@@ -77,15 +71,15 @@ rotate (GdkPixbuf *src_pixbuf,
 	
 	for (yi = 0; yi < new_height; yi++) {
 	
-		p_new_row = p_new;
+		p_new2 = p_new;
 		
 		for (xi = 0; xi < new_width; xi++) {
 		
-			x = xi - center_dx;
-			y = yi - center_dy;
+			x = xi - (new_width - 1) / 2.0;
+			y = yi - (new_height - 1) / 2.0;
 			
-			x2 = cos_angle * x - sin_angle * y + center_x;
-			y2 = sin_angle * x + cos_angle * y + center_y;
+			x2 = cos_angle * x - sin_angle * y + (src_width - 1) / 2.0;
+			y2 = sin_angle * x + cos_angle * y + (src_height - 1) / 2.0;
 			
 			// TODO: interpolate
 			x2i = (int) floor(x2 + 0.5);
@@ -95,17 +89,17 @@ rotate (GdkPixbuf *src_pixbuf,
 			
 				p_src2 = p_src + src_rowstride * y2i + n_channels * x2i;
 			
-				p_new_row[RED_PIX]   = p_src2[RED_PIX];
-				p_new_row[GREEN_PIX] = p_src2[GREEN_PIX];
-				p_new_row[BLUE_PIX]  = p_src2[BLUE_PIX];
+				p_new2[RED_PIX]   = p_src2[RED_PIX];
+				p_new2[GREEN_PIX] = p_src2[GREEN_PIX];
+				p_new2[BLUE_PIX]  = p_src2[BLUE_PIX];
 			}
 			else {
-				p_new_row[RED_PIX]   = 0;
-				p_new_row[GREEN_PIX] = 0;
-				p_new_row[BLUE_PIX]  = 0;
+				p_new2[RED_PIX]   = 0;
+				p_new2[GREEN_PIX] = 0;
+				p_new2[BLUE_PIX]  = 0;
 			}
 			
-			p_new_row += n_channels;
+			p_new2 += n_channels;
 		}
 		
 		p_new += new_rowstride;
@@ -117,8 +111,6 @@ rotate (GdkPixbuf *src_pixbuf,
 
 GdkPixbuf*
 _gdk_pixbuf_rotate (GdkPixbuf *src_pixbuf,
-		    double     center_x,
-		    double     center_y,
 		    double     angle,
 		    gint       auto_crop)
 {
@@ -135,7 +127,7 @@ _gdk_pixbuf_rotate (GdkPixbuf *src_pixbuf,
 		new_pixbuf = gdk_pixbuf_rotate_simple (src_pixbuf, GDK_PIXBUF_ROTATE_COUNTERCLOCKWISE);
 	}
 	else {
-		new_pixbuf = rotate (src_pixbuf, center_x, center_y, -angle, auto_crop);
+		new_pixbuf = rotate (src_pixbuf, -angle, auto_crop);
 	}
 
 	return new_pixbuf;
diff --git a/extensions/file_tools/gdk-pixbuf-rotate.h b/extensions/file_tools/gdk-pixbuf-rotate.h
index b73a4b6..4566f5e 100644
--- a/extensions/file_tools/gdk-pixbuf-rotate.h
+++ b/extensions/file_tools/gdk-pixbuf-rotate.h
@@ -29,8 +29,6 @@
 G_BEGIN_DECLS
 
 GdkPixbuf* _gdk_pixbuf_rotate (GdkPixbuf *src_pixbuf,
-			       double     center_x,
-			       double     center_y,
 			       double     angle,
 			       gint       auto_crop);
 
diff --git a/extensions/file_tools/gth-file-tool-rotate.c b/extensions/file_tools/gth-file-tool-rotate.c
index fc95060..ade07fb 100644
--- a/extensions/file_tools/gth-file-tool-rotate.c
+++ b/extensions/file_tools/gth-file-tool-rotate.c
@@ -107,8 +107,6 @@ apply_cb (gpointer user_data)
 	GtkWidget         *window;
 	GtkWidget         *viewer_page;
 	double             rotation_angle;
-	double             center_x;
-	double             center_y;
 	gint               auto_crop;
 
 	if (self->priv->apply_event != 0) {
@@ -120,12 +118,10 @@ apply_cb (gpointer user_data)
 	viewer_page = gth_browser_get_viewer_page (GTH_BROWSER (window));
 
 	rotation_angle = gtk_range_get_value (GTK_RANGE (self->priv->rotation_angle));
-	center_x = (self->priv->pixbuf_width - 1) / 2.0;
-	center_y = (self->priv->pixbuf_height - 1) / 2.0;
 	auto_crop = gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON (self->priv->auto_crop));
 	
 	_g_object_unref (self->priv->dest_pixbuf);
-	self->priv->dest_pixbuf = _gdk_pixbuf_rotate (self->priv->src_pixbuf, center_x, center_y, rotation_angle, auto_crop);
+	self->priv->dest_pixbuf = _gdk_pixbuf_rotate (self->priv->src_pixbuf, rotation_angle, auto_crop);
 
 	gth_image_viewer_page_set_pixbuf (GTH_IMAGE_VIEWER_PAGE (viewer_page), self->priv->dest_pixbuf, FALSE);