merge from trunk (r12487)

(bzr r11668.1.75)

1 files changed, 81 insertions, 45 deletions

diff --git a/src/splivarot.cpp b/src/splivarot.cpp
index d07de51e3..8a57fa98a 100644
--- a/src/splivarot.cpp
+++ b/src/splivarot.cpp
@@ -34,6 +34,7 @@
 #include "style.h"
 #include "document.h"
 #include "document-undo.h"
+#include "layer-model.h"
 #include "message-stack.h"
 #include "selection.h"
 #include "desktop-handles.h"
@@ -59,56 +60,67 @@ using Inkscape::DocumentUndo;
 
 bool   Ancetre(Inkscape::XML::Node *a, Inkscape::XML::Node *who);
 
-void sp_selected_path_boolop(SPDesktop *desktop, bool_op bop, const unsigned int verb=SP_VERB_NONE, const Glib::ustring description="");
+void sp_selected_path_boolop(Inkscape::Selection *selection, SPDesktop *desktop, bool_op bop, const unsigned int verb=SP_VERB_NONE, const Glib::ustring description="");
 void sp_selected_path_do_offset(SPDesktop *desktop, bool expand, double prefOffset);
 void sp_selected_path_create_offset_object(SPDesktop *desktop, int expand, bool updating);
 
 void
-sp_selected_path_union(SPDesktop *desktop)
+sp_selected_path_union(Inkscape::Selection *selection, SPDesktop *desktop)
 {
-    sp_selected_path_boolop(desktop, bool_op_union, SP_VERB_SELECTION_UNION, _("Union"));
+    sp_selected_path_boolop(selection, desktop, bool_op_union, SP_VERB_SELECTION_UNION, _("Union"));
 }
 
 void
-sp_selected_path_union_skip_undo(SPDesktop *desktop)
+sp_selected_path_union_skip_undo(Inkscape::Selection *selection, SPDesktop *desktop)
 {
-    sp_selected_path_boolop(desktop, bool_op_union, SP_VERB_NONE, _("Union"));
+    sp_selected_path_boolop(selection, desktop, bool_op_union, SP_VERB_NONE, _("Union"));
 }
 
 void
-sp_selected_path_intersect(SPDesktop *desktop)
+sp_selected_path_intersect(Inkscape::Selection *selection, SPDesktop *desktop)
 {
-    sp_selected_path_boolop(desktop, bool_op_inters, SP_VERB_SELECTION_INTERSECT, _("Intersection"));
+    sp_selected_path_boolop(selection, desktop, bool_op_inters, SP_VERB_SELECTION_INTERSECT, _("Intersection"));
 }
 
 void
-sp_selected_path_diff(SPDesktop *desktop)
+sp_selected_path_diff(Inkscape::Selection *selection, SPDesktop *desktop)
 {
-    sp_selected_path_boolop(desktop, bool_op_diff, SP_VERB_SELECTION_DIFF, _("Difference"));
+    sp_selected_path_boolop(selection, desktop, bool_op_diff, SP_VERB_SELECTION_DIFF, _("Difference"));
 }
 
 void
-sp_selected_path_diff_skip_undo(SPDesktop *desktop)
+sp_selected_path_diff_skip_undo(Inkscape::Selection *selection, SPDesktop *desktop)
 {
-    sp_selected_path_boolop(desktop, bool_op_diff, SP_VERB_NONE, _("Difference"));
+    sp_selected_path_boolop(selection, desktop, bool_op_diff, SP_VERB_NONE, _("Difference"));
 }
 
 void
-sp_selected_path_symdiff(SPDesktop *desktop)
+sp_selected_path_symdiff(Inkscape::Selection *selection, SPDesktop *desktop)
 {
-    sp_selected_path_boolop(desktop, bool_op_symdiff, SP_VERB_SELECTION_SYMDIFF, _("Exclusion"));
+    sp_selected_path_boolop(selection, desktop, bool_op_symdiff, SP_VERB_SELECTION_SYMDIFF, _("Exclusion"));
 }
 void
-sp_selected_path_cut(SPDesktop *desktop)
+sp_selected_path_cut(Inkscape::Selection *selection, SPDesktop *desktop)
 {
-    sp_selected_path_boolop(desktop, bool_op_cut, SP_VERB_SELECTION_CUT, _("Division"));
+    sp_selected_path_boolop(selection, desktop, bool_op_cut, SP_VERB_SELECTION_CUT, _("Division"));
 }
 void
-sp_selected_path_slice(SPDesktop *desktop)
+sp_selected_path_slice(Inkscape::Selection *selection, SPDesktop *desktop)
 {
-    sp_selected_path_boolop(desktop, bool_op_slice, SP_VERB_SELECTION_SLICE,  _("Cut path"));
+    sp_selected_path_boolop(selection, desktop, bool_op_slice, SP_VERB_SELECTION_SLICE,  _("Cut path"));
 }
 
+// helper for printing error messages, regardless of whether we have a GUI or not
+// If desktop == NULL, errors will be shown on stderr
+static void
+boolop_display_error_message(SPDesktop *desktop, Glib::ustring const &msg)
+{
+    if (desktop) {
+        desktop->messageStack()->flash(Inkscape::ERROR_MESSAGE, msg);
+    } else {
+        g_printerr("%s\n", msg.c_str());
+    }
+}
 
 // boolean operations PathVectors A,B -> PathVector result.
 // This is derived from sp_selected_path_boolop
@@ -311,25 +323,24 @@ Geom::PathVector pathliv_to_pathvector(Path *pathliv){
 // boolean operations on the desktop
 // take the source paths from the file, do the operation, delete the originals and add the results
 void
-sp_selected_path_boolop(SPDesktop *desktop, bool_op bop, const unsigned int verb, const Glib::ustring description)
+sp_selected_path_boolop(Inkscape::Selection *selection, SPDesktop *desktop, bool_op bop, const unsigned int verb, const Glib::ustring description)
 {
-    Inkscape::Selection *selection = sp_desktop_selection(desktop);
-    
+    SPDocument *doc = selection->layers()->getDocument();
     GSList *il = (GSList *) selection->itemList();
     
     // allow union on a single object for the purpose of removing self overlapse (svn log, revision 13334)
     if ( (g_slist_length(il) < 2) && (bop != bool_op_union)) {
-        desktop->messageStack()->flash(Inkscape::ERROR_MESSAGE, _("Select <b>at least 2 paths</b> to perform a boolean operation."));
+        boolop_display_error_message(desktop, _("Select <b>at least 2 paths</b> to perform a boolean operation."));
         return;
     }
     else if ( g_slist_length(il) < 1 ) {
-        desktop->messageStack()->flash(Inkscape::ERROR_MESSAGE, _("Select <b>at least 1 path</b> to perform a boolean union."));
+        boolop_display_error_message(desktop, _("Select <b>at least 1 path</b> to perform a boolean union."));
         return;
     }
 
     if (g_slist_length(il) > 2) {
         if (bop == bool_op_diff || bop == bool_op_cut || bop == bool_op_slice ) {
-            desktop->messageStack()->flash(Inkscape::ERROR_MESSAGE, _("Select <b>exactly 2 paths</b> to perform difference, division, or path cut."));
+            boolop_display_error_message(desktop, _("Select <b>exactly 2 paths</b> to perform difference, division, or path cut."));
             return;
         }
     }
@@ -345,7 +356,7 @@ sp_selected_path_boolop(SPDesktop *desktop, bool_op bop, const unsigned int verb
         Inkscape::XML::Node *b = reinterpret_cast<SPObject *>(il->next->data)->getRepr();
 
         if (a == NULL || b == NULL) {
-            desktop->messageStack()->flash(Inkscape::ERROR_MESSAGE, _("Unable to determine the <b>z-order</b> of the objects selected for difference, XOR, division, or path cut."));
+            boolop_display_error_message(desktop, _("Unable to determine the <b>z-order</b> of the objects selected for difference, XOR, division, or path cut."));
             return;
         }
 
@@ -360,7 +371,7 @@ sp_selected_path_boolop(SPDesktop *desktop, bool_op bop, const unsigned int verb
             // find their lowest common ancestor
             Inkscape::XML::Node *dad = LCA(a, b);
             if (dad == NULL) {
-                desktop->messageStack()->flash(Inkscape::ERROR_MESSAGE, _("Unable to determine the <b>z-order</b> of the objects selected for difference, XOR, division, or path cut."));
+                boolop_display_error_message(desktop, _("Unable to determine the <b>z-order</b> of the objects selected for difference, XOR, division, or path cut."));
                 return;
             }
 
@@ -390,7 +401,7 @@ sp_selected_path_boolop(SPDesktop *desktop, bool_op bop, const unsigned int verb
         SPItem *item = SP_ITEM(l->data);
         if (!SP_IS_SHAPE(item) && !SP_IS_TEXT(item) && !SP_IS_FLOWTEXT(item))
         {
-            desktop->messageStack()->flash(Inkscape::ERROR_MESSAGE, _("One of the objects is <b>not a path</b>, cannot perform boolean operation."));
+            boolop_display_error_message(desktop, _("One of the objects is <b>not a path</b>, cannot perform boolean operation."));
             g_slist_free(il);
             return;
         }
@@ -465,11 +476,38 @@ sp_selected_path_boolop(SPDesktop *desktop, bool_op bop, const unsigned int verb
 
             theShapeB->ConvertToShape(theShape, origWind[curOrig]);
 
-            if (theShapeA->numberOfEdges() == 0) {
-                Shape *swap = theShapeB;
-                theShapeB = theShapeA;
-                theShapeA = swap;
-            } else if (theShapeB->numberOfEdges() > 0) {
+            /* Due to quantization of the input shape coordinates, we may end up with A or B being empty.
+             * If this is a union or symdiff operation, we just use the non-empty shape as the result:
+             *   A=0  =>  (0 or B) == B
+             *   B=0  =>  (A or 0) == A
+             *   A=0  =>  (0 xor B) == B
+             *   B=0  =>  (A xor 0) == A
+             * If this is an intersection operation, we just use the empty shape as the result:
+             *   A=0  =>  (0 and B) == 0 == A
+             *   B=0  =>  (A and 0) == 0 == B
+             * If this a difference operation, and the upper shape (A) is empty, we keep B.
+             * If the lower shape (B) is empty, we still keep B, as it's empty:
+             *   A=0  =>  (B - 0) == B
+             *   B=0  =>  (0 - A) == 0 == B
+             *
+             * In any case, the output from this operation is stored in shape A, so we may apply
+             * the above rules simply by judicious use of swapping A and B where necessary.
+             */
+            bool zeroA = theShapeA->numberOfEdges() == 0;
+            bool zeroB = theShapeB->numberOfEdges() == 0;
+            if (zeroA || zeroB) {
+            	// We might need to do a swap. Apply the above rules depending on operation type.
+            	bool resultIsB =   ((bop == bool_op_union || bop == bool_op_symdiff) && zeroA)
+            		        || ((bop == bool_op_inters) && zeroB)
+            			||  (bop == bool_op_diff);
+                if (resultIsB) {
+                	// Swap A and B to use B as the result
+                    Shape *swap = theShapeB;
+                    theShapeB = theShapeA;
+                    theShapeA = swap;
+                }
+            } else {
+            	// Just do the Boolean operation as usual
                 // les elements arrivent en ordre inverse dans la liste
                 theShape->Booleen(theShapeB, theShapeA, bop);
                 Shape *swap = theShape;
@@ -631,8 +669,7 @@ sp_selected_path_boolop(SPDesktop *desktop, bool_op bop, const unsigned int verb
         {
             SP_OBJECT(l->data)->deleteObject();
         }
-        DocumentUndo::done(sp_desktop_document(desktop), SP_VERB_NONE, 
-                           description);
+        DocumentUndo::done(doc, SP_VERB_NONE, description);
         selection->clear();
 
         delete res;
@@ -654,8 +691,7 @@ sp_selected_path_boolop(SPDesktop *desktop, bool_op bop, const unsigned int verb
 
         sorted = g_slist_sort(sorted, (GCompareFunc) sp_repr_compare_position);
 
-        source = sp_desktop_document(desktop)->
-            getObjectByRepr((Inkscape::XML::Node *)sorted->data);
+        source = doc->getObjectByRepr((Inkscape::XML::Node *)sorted->data);
 
         g_slist_free(sorted);
     }
@@ -695,7 +731,7 @@ sp_selected_path_boolop(SPDesktop *desktop, bool_op bop, const unsigned int verb
     g_slist_free(il);
 
     // premultiply by the inverse of parent's repr
-    SPItem *parent_item = SP_ITEM(sp_desktop_document(desktop)->getObjectByRepr(parent));
+    SPItem *parent_item = SP_ITEM(doc->getObjectByRepr(parent));
     Geom::Affine local (parent_item->i2doc_affine());
     gchar *transform = sp_svg_transform_write(local.inverse());
 
@@ -725,7 +761,7 @@ sp_selected_path_boolop(SPDesktop *desktop, bool_op bop, const unsigned int verb
         for (int i=0;i<nbRP;i++) {
             gchar *d = resPath[i]->svg_dump_path();
 
-            Inkscape::XML::Document *xml_doc = desktop->doc()->getReprDoc();
+            Inkscape::XML::Document *xml_doc = doc->getReprDoc();
             Inkscape::XML::Node *repr = xml_doc->createElement("svg:path");
             repr->setAttribute("style", style);
             if (mask)
@@ -771,7 +807,7 @@ sp_selected_path_boolop(SPDesktop *desktop, bool_op bop, const unsigned int verb
     } else {
         gchar *d = res->svg_dump_path();
 
-        Inkscape::XML::Document *xml_doc = desktop->doc()->getReprDoc();
+        Inkscape::XML::Document *xml_doc = doc->getReprDoc();
         Inkscape::XML::Node *repr = xml_doc->createElement("svg:path");
         repr->setAttribute("style", style);
 
@@ -789,10 +825,10 @@ sp_selected_path_boolop(SPDesktop *desktop, bool_op bop, const unsigned int verb
         repr->setAttribute("id", id);
         parent->appendChild(repr);
         if (title) {
-        	sp_desktop_document(desktop)->getObjectByRepr(repr)->setTitle(title);
+        	doc->getObjectByRepr(repr)->setTitle(title);
         }            
         if (desc) {
-        	sp_desktop_document(desktop)->getObjectByRepr(repr)->setDesc(desc);
+        	doc->getObjectByRepr(repr)->setDesc(desc);
         }
 		repr->setPosition(pos > 0 ? pos : 0);
 
@@ -805,7 +841,7 @@ sp_selected_path_boolop(SPDesktop *desktop, bool_op bop, const unsigned int verb
     if (desc) g_free(desc);
 
     if (verb != SP_VERB_NONE) {
-        DocumentUndo::done(sp_desktop_document(desktop), verb, description);
+        DocumentUndo::done(doc, verb, description);
     }
 
     delete res;
@@ -1764,12 +1800,12 @@ sp_selected_path_do_offset(SPDesktop *desktop, bool expand, double prefOffset)
         float o_width = 0;
         float o_miter = 0;
         JoinType o_join = join_straight;
-        ButtType o_butt = butt_straight;
+        //ButtType o_butt = butt_straight;
 
         {
             SPStyle *i_style = item->style;
             int jointype = i_style->stroke_linejoin.value;
-            int captype = i_style->stroke_linecap.value;
+            //int captype = i_style->stroke_linecap.value;
 
             o_width = i_style->stroke_width.computed;
 
@@ -1785,7 +1821,7 @@ sp_selected_path_do_offset(SPDesktop *desktop, bool expand, double prefOffset)
                     break;
             }
 
-            switch (captype) {
+            /*switch (captype) {
                 case SP_STROKE_LINECAP_SQUARE:
                     o_butt = butt_square;
                     break;
@@ -1795,7 +1831,7 @@ sp_selected_path_do_offset(SPDesktop *desktop, bool expand, double prefOffset)
                 default:
                     o_butt = butt_straight;
                     break;
-            }
+            }*/
 
             o_width = prefOffset;