Fix "Windows: dotted lines may be drawn solid when GUI is rescaled" (#1214)

1 files changed, 4 insertions, 2 deletions

diff --git a/src/Fl_Graphics_Driver.cxx b/src/Fl_Graphics_Driver.cxx
index 4f69967d6..9ef46f9f3 100644
--- a/src/Fl_Graphics_Driver.cxx
+++ b/src/Fl_Graphics_Driver.cxx
@@ -800,6 +800,7 @@ Fl_Font_Descriptor::Fl_Font_Descriptor(const char* name, Fl_Fontsize Size) {
 Fl_Scalable_Graphics_Driver::Fl_Scalable_Graphics_Driver() : Fl_Graphics_Driver() {
   line_width_ = 0;
   fontsize_ = -1;
+  is_solid_ = true;
 }
 
 void Fl_Scalable_Graphics_Driver::rect(int x, int y, int w, int h)
@@ -850,7 +851,7 @@ void Fl_Scalable_Graphics_Driver::xyline(int x, int y, int x1) {
   int xx1 = (x < x1 ? x1 : x);
   if (s != s_int && line_width_ <= s_int) {
     int lwidth = this->floor((y+1)) - this->floor(y);
-    bool need_change_width = (lwidth != s_int);
+    bool need_change_width = (lwidth != s_int && is_solid_);
     void *data = NULL;
     if (need_change_width) data = change_pen_width(lwidth);
     xyline_unscaled(this->floor(xx), this->floor(y) + int(lwidth/2.f), this->floor(xx1+1)-1);
@@ -870,7 +871,7 @@ void Fl_Scalable_Graphics_Driver::yxline(int x, int y, int y1) {
   int yy1 = (y < y1 ? y1 : y);
   if (s != s_int && line_width_ <= s_int) {
     int lwidth = (this->floor((x+1)) - this->floor(x));
-    bool need_change_width = (lwidth != s_int);
+    bool need_change_width = (lwidth != s_int && is_solid_);
     void *data = NULL;
     if (need_change_width) data = change_pen_width(lwidth);
     yxline_unscaled(this->floor(x) + int(lwidth/2.f), this->floor(yy), this->floor(yy1+1) - 1);
@@ -1050,6 +1051,7 @@ void Fl_Scalable_Graphics_Driver::draw_circle(int x0, int y0, int d, Fl_Color c)
 void Fl_Scalable_Graphics_Driver::line_style(int style, int width, char* dashes) {
   if (width == 0) line_width_ = int(scale() < 2 ? 0 : scale());
   else line_width_ = int(width>0 ? width*scale() : -width*scale());
+  is_solid_ = ((style & 0xff) == FL_SOLID && (!dashes || !*dashes));
   line_style_unscaled(style, line_width_, dashes);
 }