Fix multiple layer issue in cairo-unification branch (see #33)

1 files changed, 13 insertions, 10 deletions

diff --git a/gerber/render/cairo_backend.py b/gerber/render/cairo_backend.py
index 16638f5..2791d76 100644
--- a/gerber/render/cairo_backend.py
+++ b/gerber/render/cairo_backend.py
@@ -31,20 +31,21 @@ class GerberCairoContext(GerberContext):
         self.scale = (scale, scale)

         self.surface = None

         self.ctx = None

+        self.bg = False

         

     def set_bounds(self, bounds):

         origin_in_inch = (bounds[0][0], bounds[1][0])

         size_in_inch = (abs(bounds[0][1] - bounds[0][0]), abs(bounds[1][1] - bounds[1][0]))

         size_in_pixels = map(mul, size_in_inch, self.scale)

 

-        self.surface_buffer = tempfile.NamedTemporaryFile()

-

-        self.surface = cairo.SVGSurface(self.surface_buffer, size_in_pixels[0], size_in_pixels[1])

-        self.ctx = cairo.Context(self.surface)

-        self.ctx.set_fill_rule(cairo.FILL_RULE_EVEN_ODD)

-        self.ctx.scale(1, -1)

-        self.ctx.translate(-(origin_in_inch[0] * self.scale[0]), (-origin_in_inch[1]*self.scale[0]) - size_in_pixels[1])

-        # self.ctx.translate(-(origin_in_inch[0] * self.scale[0]), -origin_in_inch[1]*self.scale[1])

+        if self.surface is None:

+            self.surface_buffer = tempfile.NamedTemporaryFile()

+            self.surface = cairo.SVGSurface(self.surface_buffer, size_in_pixels[0], size_in_pixels[1])

+            self.ctx = cairo.Context(self.surface)

+            self.ctx.set_fill_rule(cairo.FILL_RULE_EVEN_ODD)

+            self.ctx.scale(1, -1)

+            self.ctx.translate(-(origin_in_inch[0] * self.scale[0]), (-origin_in_inch[1]*self.scale[0]) - size_in_pixels[1])

+            # self.ctx.translate(-(origin_in_inch[0] * self.scale[0]), -origin_in_inch[1]*self.scale[1])

 

     def _render_line(self, line, color):

         start = map(mul, line.start, self.scale)

@@ -140,8 +141,10 @@ class GerberCairoContext(GerberContext):
         self.ctx.set_operator(cairo.OPERATOR_CLEAR)

 

     def _paint_background(self):

-        self.ctx.set_source_rgba(*self.background_color)

-        self.ctx.paint()

+        if not self.bg:

+            self.bg = True

+            self.ctx.set_source_rgba(*self.background_color)

+            self.ctx.paint()

 

     def dump(self, filename):

         is_svg = filename.lower().endswith(".svg")