cairo support

gerber/render/cairo_backend.py

@@ -0,0 +1,156 @@
+#! /usr/bin/env python
+# -*- coding: utf-8 -*-
+
+# Copyright 2014 Hamilton Kibbe <ham@hamiltonkib.be>
+
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+
+#     http://www.apache.org/licenses/LICENSE-2.0
+
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from .render import GerberContext
+from .apertures import Circle, Rect, Obround, Polygon
+import cairo
+import math
+
+SCALE = 200.
+
+class CairoCircle(Circle):
+    def line(self, ctx, x, y, color=(184/255., 115/255., 51/255.)):
+        ctx.set_source_rgb (*color)
+        ctx.set_line_width(self.diameter * SCALE)
+        ctx.set_line_cap(cairo.LINE_CAP_ROUND)
+        ctx.line_to(x * SCALE, y * SCALE)
+        ctx.stroke()
+        
+    def arc(self, ctx, x, y, i, j, direction, color=(184/255., 115/255., 51/255.)):
+        ctx_x, ctx_y = ctx.get_current_point()
+        
+        # Do the math
+        center = ((x + i) * SCALE, (y + j) * SCALE)
+        radius = math.sqrt(math.pow(ctx_x - center[0], 2) + math.pow(ctx_y - center[1], 2))
+        delta_x0 = (ctx_x - center[0])
+        delta_y0 = (ctx_y - center[1])
+        delta_x1 = (x * SCALE - center[0])
+        delta_y1 = (y * SCALE - center[1])
+        theta0 = math.atan2(delta_y0, delta_x0)
+        theta1 = math.atan2(delta_y1, delta_x1)
+        # Draw the arc
+        ctx.set_source_rgb (*color)
+        ctx.set_line_width(self.diameter * SCALE)
+        ctx.set_line_cap(cairo.LINE_CAP_ROUND)
+        if direction == 'clockwise':
+            ctx.arc_negative(center[0], center[1], radius, theta0, theta1)
+        else:
+            ctx.arc(center[0], center[1], radius, theta0, theta1)
+        ctx.stroke()
+
+    def flash(self, ctx, x, y, color=(184/255., 115/255., 51/255.)):
+        ctx.set_source_rgb (*color)
+        ctx.set_line_width(0)
+        ctx.arc(x * SCALE, y * SCALE, (self.diameter/2.) * SCALE, 0, 2 * math.pi)
+        ctx.fill()
+
+class CairoRect(Rect):
+    def line(self, ctx, x, y, color=(184/255., 115/255., 51/255.)):
+        ctx.set_source_rgb (*color)
+        ctx.set_line_width(self.diameter * SCALE)
+        ctx.set_line_cap(cairo.LINE_CAP_SQUARE)
+        ctx.line_to(x * SCALE, y * SCALE)
+        ctx.stroke()
+        
+    def flash(self, ctx, x, y, color=(184/255., 115/255., 51/255.)):
+        xsize, ysize = self.size
+        ctx.set_source_rgb (*color)
+        ctx.set_line_width(0)
+        x0 = SCALE * (x - (xsize / 2.))
+        y0 = SCALE * (y - (ysize / 2.))
+
+        ctx.rectangle(x0,y0,SCALE * xsize, SCALE * ysize)
+        ctx.fill()
+
+
+
+class GerberCairoContext(GerberContext):
+    def __init__(self, surface=None, size=(1000, 1000), 
+                 color='rgb(184, 115, 51)', drill_color='gray'):
+        GerberContext.__init__(self)
+        if surface is None:
+            self.surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, 
+                                              size[0], size[1])
+        else:
+             self.surface = surface
+        self.ctx = cairo.Context(self.surface)
+        self.size = size
+        self.ctx.translate(0, self.size[1])
+        self.ctx.scale(1,-1)
+        self.apertures = {}
+        self.color = color
+        self.drill_color = drill_color
+        self.background = False
+        
+    def set_bounds(self, bounds):
+        xbounds, ybounds = bounds
+        self.ctx.rectangle(SCALE * xbounds[0], SCALE * ybounds[0], SCALE * (xbounds[1]- xbounds[0]), SCALE * (ybounds[1] - ybounds[0]))
+        self.ctx.set_source_rgb(0,0,0)
+        self.ctx.fill()
+
+    def define_aperture(self, d, shape, modifiers):
+        aperture = None
+        if shape == 'C':
+            aperture = CairoCircle(diameter=float(modifiers[0][0]))
+        elif shape == 'R':
+            aperture = CairoRect(size=modifiers[0][0:2])
+        self.apertures[d] = aperture
+        
+    def stroke(self, x, y, i, j):
+        super(GerberCairoContext, self).stroke(x, y, i, j)
+
+        if self.interpolation == 'linear':
+            self.line(x, y)
+        elif self.interpolation == 'arc':
+            self.arc(x, y, i, j)
+            self.move(x,y)
+            
+    def line(self, x, y):
+        x, y = self.resolve(x, y)
+        ap = self.apertures.get(self.aperture, None)
+        if ap is None:
+            return
+        ap.line(self.ctx, x, y)
+
+    def arc(self, x, y, i, j):
+        super(GerberCairoContext, self).arc(x, y, i, j)
+        ap = self.apertures.get(self.aperture, None)
+        if ap is None:
+            return
+        ap.arc(self.ctx, x, y, i, j, self.direction)
+        
+        
+    def flash(self, x, y):
+        x, y = self.resolve(x, y)
+        ap = self.apertures.get(self.aperture, None)
+        if ap is None:
+            return
+        ap.flash(self.ctx, x, y)
+        self.move(x, y, resolve=False)
+        
+    def move(self, x, y, resolve=True):
+        super(GerberCairoContext, self).move(x, y, resolve)
+        if x is None:
+            x = self.x
+        if y is None:
+            y = self.y
+        if self.x is not None and self.y is not None:
+            self.ctx.move_to(x * SCALE, y * SCALE)
+
+
+    def dump(self, filename):
+        self.surface.write_to_png(filename)