patch bug 1294784

(bzr r14167)

2 files changed, 17 insertions, 1 deletions

diff --git a/src/display/drawing-text.cpp b/src/display/drawing-text.cpp
index e20a7ff2a..3928ad796 100644
--- a/src/display/drawing-text.cpp
+++ b/src/display/drawing-text.cpp
@@ -367,7 +367,7 @@ void DrawingText::decorateStyle(DrawingContext &dc, double vextent, double xphas
 /* returns scaled line thickness */
 void DrawingText::decorateItem(DrawingContext &dc, double phase_length, bool under)
 {
-    if (_nrstyle.font_size < 1.0e-32)return;  // would cause a divide by zero and nothing would be visible anyway
+    if ( _nrstyle.font_size <= 1.0e-32 )return;  // might cause a divide by zero or overflow and nothing would be visible anyway
     double tsp_width_adj                = _nrstyle.tspan_width                     / _nrstyle.font_size;
     double tsp_asc_adj                  = _nrstyle.ascender                        / _nrstyle.font_size;
     double tsp_size_adj                 = (_nrstyle.ascender + _nrstyle.descender) / _nrstyle.font_size;
@@ -381,6 +381,7 @@ void DrawingText::decorateItem(DrawingContext &dc, double phase_length, bool und
     Geom::Point p2;
     // All lines must be the same thickness, in combinations, line_through trumps underline
     double thickness = final_underline_thickness;
+    if ( thickness <= 1.0e-32 )return;  // might cause a divide by zero or overflow and nothing would be visible anyway
     dc.setTolerance(0.5); // Is this really necessary... could effect dots.
 
     if( under ) {
diff --git a/src/style-internal.cpp b/src/style-internal.cpp
index 0e53da0d3..c117a97f9 100644
--- a/src/style-internal.cpp
+++ b/src/style-internal.cpp
@@ -1931,6 +1931,11 @@ SPIFontSize::read( gchar const *str ) {
             unit     = length.unit;
             value    = length.value;
             computed = length.computed;
+            /*  Set a minimum font size to something much smaller than should ever (ever!) be encountered in a real file.
+                If a bad SVG file is encountered and this is zero odd things
+                might happen because the inverse is used in some scaling actions.
+            */
+            if ( computed <= 1.0e-32 ) { computed = 1.0e-32; }
             if( unit == SP_CSS_UNIT_PERCENT ) {
                 type = SP_FONT_SIZE_PERCENTAGE;
             } else {
@@ -2011,6 +2016,11 @@ SPIFontSize::cascade( const SPIBase* const parent ) {
                     break;
             }
         }
+        /*  Set a minimum font size to something much smaller than should ever (ever!) be encountered in a real file.
+            If a bad SVG file is encountered and this is zero odd things
+            might happen because the inverse is used in some scaling actions.
+        */
+        if ( computed <= 1.0e-32 ) { computed = 1.0e-32; }
     } else {
         std::cerr << "SPIFontSize::cascade(): Incorrect parent type" << std::endl;
     }
@@ -2099,6 +2109,11 @@ SPIFontSize::merge( const SPIBase* const parent ) {
                     }
                 }
             } // Relative size
+            /*  Set a minimum font size to something much smaller than should ever (ever!) be encountered in a real file.
+                If a bad SVG file is encountered and this is zero odd things
+                might happen because the inverse is used in some scaling actions.
+            */
+            if ( computed <= 1.0e-32 ) { computed = 1.0e-32; }
         } // Parent set and not inherit
     } else {
         std::cerr << "SPIFontSize::merge(): Incorrect parent type" << std::endl;