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-rw-r--r--gerbonara/gerber/render/cairo_backend.py640
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diff --git a/gerbonara/gerber/render/cairo_backend.py b/gerbonara/gerber/render/cairo_backend.py
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--- a/gerbonara/gerber/render/cairo_backend.py
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@@ -1,640 +0,0 @@
-#!/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.
-
-try:
- import cairo
-except ImportError:
- import cairocffi as cairo
-
-from operator import mul
-import tempfile
-import warnings
-import os
-
-from .render import GerberContext, RenderSettings
-from .theme import THEMES
-from ..primitives import *
-from ..utils import rotate_point
-
-from io import BytesIO
-
-
-class GerberCairoContext(GerberContext):
-
- def __init__(self, scale=300):
- super(GerberCairoContext, self).__init__()
- self.scale = (scale, scale)
- self.surface = None
- self.surface_buffer = None
- self.ctx = None
- self.active_layer = None
- self.active_matrix = None
- self.output_ctx = None
- self.has_bg = False
- self.origin_in_inch = None
- self.size_in_inch = None
- self._xform_matrix = None
- self._render_count = 0
-
- @property
- def origin_in_pixels(self):
- return (self.scale_point(self.origin_in_inch)
- if self.origin_in_inch is not None else (0.0, 0.0))
-
- @property
- def size_in_pixels(self):
- return (self.scale_point(self.size_in_inch)
- if self.size_in_inch is not None else (0.0, 0.0))
-
- def set_bounds(self, bounds, new_surface=False):
- 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 = self.scale_point(size_in_inch)
- self.origin_in_inch = origin_in_inch if self.origin_in_inch is None else self.origin_in_inch
- self.size_in_inch = size_in_inch if self.size_in_inch is None else self.size_in_inch
- self._xform_matrix = cairo.Matrix(xx=1.0, yy=-1.0,
- x0=-self.origin_in_pixels[0],
- y0=self.size_in_pixels[1])
- if (self.surface is None) or new_surface:
- self.surface_buffer = tempfile.NamedTemporaryFile()
- self.surface = cairo.SVGSurface(self.surface_buffer, size_in_pixels[0], size_in_pixels[1])
- self.output_ctx = cairo.Context(self.surface)
-
- def render_layer(self, layer, filename=None, settings=None, bgsettings=None,
- verbose=False, bounds=None):
- if settings is None:
- settings = THEMES['default'].get(layer.layer_class, RenderSettings())
- if bgsettings is None:
- bgsettings = THEMES['default'].get('background', RenderSettings())
-
- if self._render_count == 0:
- if verbose:
- print('[Render]: Rendering Background.')
- self.clear()
- if bounds is not None:
- self.set_bounds(bounds)
- else:
- self.set_bounds(layer.bounds)
- self.paint_background(bgsettings)
- if verbose:
- print('[Render]: Rendering {} Layer.'.format(layer.layer_class))
- self._render_count += 1
- self._render_layer(layer, settings)
- if filename is not None:
- self.dump(filename, verbose)
-
- def render_layers(self, layers, filename, theme=THEMES['default'],
- verbose=False, max_width=800, max_height=600):
- """ Render a set of layers
- """
- # Calculate scale parameter
- x_range = [10000, -10000]
- y_range = [10000, -10000]
- for layer in layers:
- bounds = layer.bounds
- if bounds is not None:
- layer_x, layer_y = bounds
- x_range[0] = min(x_range[0], layer_x[0])
- x_range[1] = max(x_range[1], layer_x[1])
- y_range[0] = min(y_range[0], layer_y[0])
- y_range[1] = max(y_range[1], layer_y[1])
- width = x_range[1] - x_range[0]
- height = y_range[1] - y_range[0]
-
- scale = math.floor(min(float(max_width)/width, float(max_height)/height))
- self.scale = (scale, scale)
-
- self.clear()
-
- # Render layers
- bgsettings = theme['background']
- for layer in layers:
- settings = theme.get(layer.layer_class, RenderSettings())
- self.render_layer(layer, settings=settings, bgsettings=bgsettings,
- verbose=verbose)
- self.dump(filename, verbose)
-
- def dump(self, filename=None, verbose=False):
- """ Save image as `filename`
- """
- try:
- is_svg = os.path.splitext(filename.lower())[1] == '.svg'
- except:
- is_svg = False
-
- if verbose:
- print('[Render]: Writing image to {}'.format(filename))
-
- if is_svg:
- self.surface.finish()
- self.surface_buffer.flush()
- with open(filename, "wb") as f:
- self.surface_buffer.seek(0)
- f.write(self.surface_buffer.read())
- f.flush()
- else:
- return self.surface.write_to_png(filename)
-
- def dump_str(self):
- """ Return a byte-string containing the rendered image.
- """
- fobj = BytesIO()
- self.surface.write_to_png(fobj)
- return fobj.getvalue()
-
- def dump_svg_str(self):
- """ Return a string containg the rendered SVG.
- """
- self.surface.finish()
- self.surface_buffer.flush()
- return self.surface_buffer.read()
-
- def clear(self):
- self.surface = None
- self.output_ctx = None
- self.has_bg = False
- self.origin_in_inch = None
- self.size_in_inch = None
- self._xform_matrix = None
- self._render_count = 0
- self.surface_buffer = None
-
- def _new_mask(self):
- class Mask:
- def __enter__(msk):
- size_in_pixels = self.size_in_pixels
- msk.surface = cairo.SVGSurface(None, size_in_pixels[0],
- size_in_pixels[1])
- msk.ctx = cairo.Context(msk.surface)
- msk.ctx.translate(-self.origin_in_pixels[0], -self.origin_in_pixels[1])
- return msk
-
-
- def __exit__(msk, exc_type, exc_val, traceback):
- if hasattr(msk.surface, 'finish'):
- msk.surface.finish()
-
- return Mask()
-
- def _render_layer(self, layer, settings):
- self.invert = settings.invert
- # Get a new clean layer to render on
- self.new_render_layer(mirror=settings.mirror)
- for prim in layer.primitives:
- self.render(prim)
- # Add layer to image
- self.flatten(settings.color, settings.alpha)
-
- def _render_line(self, line, color):
- start = self.scale_point(line.start)
- end = self.scale_point(line.end)
- self.ctx.set_operator(cairo.OPERATOR_OVER
- if (not self.invert)
- and line.level_polarity == 'dark'
- else cairo.OPERATOR_CLEAR)
-
- with self._clip_primitive(line):
- with self._new_mask() as mask:
- if isinstance(line.aperture, Circle):
- width = line.aperture.diameter
- mask.ctx.set_line_width(width * self.scale[0])
- mask.ctx.set_line_cap(cairo.LINE_CAP_ROUND)
- mask.ctx.move_to(*start)
- mask.ctx.line_to(*end)
- mask.ctx.stroke()
-
- elif hasattr(line, 'vertices') and line.vertices is not None:
- points = [self.scale_point(x) for x in line.vertices]
- mask.ctx.set_line_width(0)
- mask.ctx.move_to(*points[-1])
- for point in points:
- mask.ctx.line_to(*point)
- mask.ctx.fill()
- self.ctx.mask_surface(mask.surface, self.origin_in_pixels[0])
-
- def _render_arc(self, arc, color):
- center = self.scale_point(arc.center)
- start = self.scale_point(arc.start)
- end = self.scale_point(arc.end)
- radius = self.scale[0] * arc.radius
- two_pi = 2 * math.pi
- angle1 = (arc.start_angle + two_pi) % two_pi
- angle2 = (arc.end_angle + two_pi) % two_pi
-
- if arc.quadrant_mode == 'single-quadrant':
- warnings.warn('Cairo backend does not support single-quadrant arcs.')
-
- if angle1 == angle2:
- # Make the angles slightly different otherwise Cario will draw nothing
- angle2 -= 0.000000001
- if isinstance(arc.aperture, Circle):
- width = arc.aperture.diameter if arc.aperture.diameter != 0 else 0.001
- else:
- width = max(arc.aperture.width, arc.aperture.height, 0.001)
-
- self.ctx.set_operator(cairo.OPERATOR_OVER
- if (not self.invert)
- and arc.level_polarity == 'dark'
- else cairo.OPERATOR_CLEAR)
- with self._clip_primitive(arc):
- with self._new_mask() as mask:
- mask.ctx.set_line_width(width * self.scale[0])
- mask.ctx.set_line_cap(cairo.LINE_CAP_ROUND if isinstance(arc.aperture, Circle) else cairo.LINE_CAP_SQUARE)
- mask.ctx.move_to(*start) # You actually have to do this...
- if arc.direction == 'counterclockwise':
- mask.ctx.arc(center[0], center[1], radius, angle1, angle2)
- else:
- mask.ctx.arc_negative(center[0], center[1], radius, angle1, angle2)
- mask.ctx.move_to(*end) # ...lame
- mask.ctx.stroke()
-
- #if isinstance(arc.aperture, Rectangle):
- # print("Flash Rectangle Ends")
- # print(arc.aperture.rotation * 180/math.pi)
- # rect = arc.aperture
- # width = self.scale[0] * rect.width
- # height = self.scale[1] * rect.height
- # for point, angle in zip((start, end), (angle1, angle2)):
- # print("{} w {} h{}".format(point, rect.width, rect.height))
- # mask.ctx.rectangle(point[0] - width/2.0,
- # point[1] - height/2.0, width, height)
- # mask.ctx.fill()
-
- self.ctx.mask_surface(mask.surface, self.origin_in_pixels[0])
-
- def _render_region(self, region, color):
- self.ctx.set_operator(cairo.OPERATOR_OVER
- if (not self.invert) and region.level_polarity == 'dark'
- else cairo.OPERATOR_CLEAR)
- with self._clip_primitive(region):
- with self._new_mask() as mask:
- mask.ctx.set_line_width(0)
- mask.ctx.set_line_cap(cairo.LINE_CAP_ROUND)
- mask.ctx.move_to(*self.scale_point(region.primitives[0].start))
- for prim in region.primitives:
- if isinstance(prim, Line):
- mask.ctx.line_to(*self.scale_point(prim.end))
- else:
- center = self.scale_point(prim.center)
- radius = self.scale[0] * prim.radius
- angle1 = prim.start_angle
- angle2 = prim.end_angle
-
- if angle1 == angle2:
- # Make the angles slightly different otherwise Cario will draw nothing
- angle2 -= 0.000000001
- if prim.direction == 'counterclockwise':
- mask.ctx.arc(center[0], center[1], radius,
- angle1, angle2)
- else:
- mask.ctx.arc_negative(center[0], center[1], radius,
- angle1, angle2)
- mask.ctx.fill()
- self.ctx.mask_surface(mask.surface, self.origin_in_pixels[0])
-
- def _render_circle(self, circle, color):
- center = self.scale_point(circle.position)
- self.ctx.set_operator(cairo.OPERATOR_OVER
- if (not self.invert)
- and circle.level_polarity == 'dark'
- else cairo.OPERATOR_CLEAR)
- with self._clip_primitive(circle):
- with self._new_mask() as mask:
- mask.ctx.set_line_width(0)
- mask.ctx.arc(center[0], center[1], (circle.radius * self.scale[0]), 0, (2 * math.pi))
- mask.ctx.fill()
-
- if hasattr(circle, 'hole_diameter') and circle.hole_diameter is not None and circle.hole_diameter > 0:
- mask.ctx.set_operator(cairo.OPERATOR_CLEAR)
- mask.ctx.arc(center[0], center[1], circle.hole_radius * self.scale[0], 0, 2 * math.pi)
- mask.ctx.fill()
-
- if (hasattr(circle, 'hole_width') and hasattr(circle, 'hole_height')
- and circle.hole_width is not None and circle.hole_height is not None
- and circle.hole_width > 0 and circle.hole_height > 0):
- mask.ctx.set_operator(cairo.OPERATOR_CLEAR
- if circle.level_polarity == 'dark'
- and (not self.invert)
- else cairo.OPERATOR_OVER)
- width, height = self.scale_point((circle.hole_width, circle.hole_height))
- lower_left = rotate_point(
- (center[0] - width / 2.0, center[1] - height / 2.0),
- circle.rotation, center)
- lower_right = rotate_point((center[0] + width / 2.0, center[1] - height / 2.0),
- circle.rotation, center)
- upper_left = rotate_point((center[0] - width / 2.0, center[1] + height / 2.0),
- circle.rotation, center)
- upper_right = rotate_point((center[0] + width / 2.0, center[1] + height / 2.0),
- circle.rotation, center)
- points = (lower_left, lower_right, upper_right, upper_left)
- mask.ctx.move_to(*points[-1])
- for point in points:
- mask.ctx.line_to(*point)
- mask.ctx.fill()
- self.ctx.mask_surface(mask.surface, self.origin_in_pixels[0])
-
- def _render_rectangle(self, rectangle, color):
- lower_left = self.scale_point(rectangle.lower_left)
- width, height = tuple([abs(coord) for coord in
- self.scale_point((rectangle.width,
- rectangle.height))])
- self.ctx.set_operator(cairo.OPERATOR_OVER
- if (not self.invert)
- and rectangle.level_polarity == 'dark'
- else cairo.OPERATOR_CLEAR)
- with self._clip_primitive(rectangle):
- with self._new_mask() as mask:
- mask.ctx.set_line_width(0)
- mask.ctx.rectangle(lower_left[0], lower_left[1], width, height)
- mask.ctx.fill()
-
- center = self.scale_point(rectangle.position)
- if rectangle.hole_diameter > 0:
- # Render the center clear
- mask.ctx.set_operator(cairo.OPERATOR_CLEAR
- if rectangle.level_polarity == 'dark'
- and (not self.invert)
- else cairo.OPERATOR_OVER)
-
- mask.ctx.arc(center[0], center[1], rectangle.hole_radius * self.scale[0], 0, 2 * math.pi)
- mask.ctx.fill()
-
- if rectangle.hole_width > 0 and rectangle.hole_height > 0:
- mask.ctx.set_operator(cairo.OPERATOR_CLEAR
- if rectangle.level_polarity == 'dark'
- and (not self.invert)
- else cairo.OPERATOR_OVER)
- width, height = self.scale_point((rectangle.hole_width, rectangle.hole_height))
- lower_left = rotate_point((center[0] - width/2.0, center[1] - height/2.0), rectangle.rotation, center)
- lower_right = rotate_point((center[0] + width/2.0, center[1] - height/2.0), rectangle.rotation, center)
- upper_left = rotate_point((center[0] - width / 2.0, center[1] + height / 2.0), rectangle.rotation, center)
- upper_right = rotate_point((center[0] + width / 2.0, center[1] + height / 2.0), rectangle.rotation, center)
- points = (lower_left, lower_right, upper_right, upper_left)
- mask.ctx.move_to(*points[-1])
- for point in points:
- mask.ctx.line_to(*point)
- mask.ctx.fill()
- self.ctx.mask_surface(mask.surface, self.origin_in_pixels[0])
-
- def _render_obround(self, obround, color):
- self.ctx.set_operator(cairo.OPERATOR_OVER
- if (not self.invert)
- and obround.level_polarity == 'dark'
- else cairo.OPERATOR_CLEAR)
- with self._clip_primitive(obround):
- with self._new_mask() as mask:
- mask.ctx.set_line_width(0)
-
- # Render circles
- for circle in (obround.subshapes['circle1'], obround.subshapes['circle2']):
- center = self.scale_point(circle.position)
- mask.ctx.arc(center[0], center[1], (circle.radius * self.scale[0]), 0, (2 * math.pi))
- mask.ctx.fill()
-
- # Render Rectangle
- rectangle = obround.subshapes['rectangle']
- lower_left = self.scale_point(rectangle.lower_left)
- width, height = tuple([abs(coord) for coord in
- self.scale_point((rectangle.width,
- rectangle.height))])
- mask.ctx.rectangle(lower_left[0], lower_left[1], width, height)
- mask.ctx.fill()
-
- center = self.scale_point(obround.position)
- if obround.hole_diameter > 0:
- # Render the center clear
- mask.ctx.set_operator(cairo.OPERATOR_CLEAR)
- mask.ctx.arc(center[0], center[1], obround.hole_radius * self.scale[0], 0, 2 * math.pi)
- mask.ctx.fill()
-
- if obround.hole_width > 0 and obround.hole_height > 0:
- mask.ctx.set_operator(cairo.OPERATOR_CLEAR
- if rectangle.level_polarity == 'dark'
- and (not self.invert)
- else cairo.OPERATOR_OVER)
- width, height =self.scale_point((obround.hole_width, obround.hole_height))
- lower_left = rotate_point((center[0] - width / 2.0, center[1] - height / 2.0),
- obround.rotation, center)
- lower_right = rotate_point((center[0] + width / 2.0, center[1] - height / 2.0),
- obround.rotation, center)
- upper_left = rotate_point((center[0] - width / 2.0, center[1] + height / 2.0),
- obround.rotation, center)
- upper_right = rotate_point((center[0] + width / 2.0, center[1] + height / 2.0),
- obround.rotation, center)
- points = (lower_left, lower_right, upper_right, upper_left)
- mask.ctx.move_to(*points[-1])
- for point in points:
- mask.ctx.line_to(*point)
- mask.ctx.fill()
-
- self.ctx.mask_surface(mask.surface, self.origin_in_pixels[0])
-
- def _render_polygon(self, polygon, color):
- self.ctx.set_operator(cairo.OPERATOR_OVER
- if (not self.invert)
- and polygon.level_polarity == 'dark'
- else cairo.OPERATOR_CLEAR)
- with self._clip_primitive(polygon):
- with self._new_mask() as mask:
-
- vertices = polygon.vertices
- mask.ctx.set_line_width(0)
- mask.ctx.set_line_cap(cairo.LINE_CAP_ROUND)
- # Start from before the end so it is easy to iterate and make sure
- # it is closed
- mask.ctx.move_to(*self.scale_point(vertices[-1]))
- for v in vertices:
- mask.ctx.line_to(*self.scale_point(v))
- mask.ctx.fill()
-
- center = self.scale_point(polygon.position)
- if polygon.hole_radius > 0:
- # Render the center clear
- mask.ctx.set_operator(cairo.OPERATOR_CLEAR
- if polygon.level_polarity == 'dark'
- and (not self.invert)
- else cairo.OPERATOR_OVER)
- mask.ctx.set_line_width(0)
- mask.ctx.arc(center[0],
- center[1],
- polygon.hole_radius * self.scale[0], 0, 2 * math.pi)
- mask.ctx.fill()
-
- if polygon.hole_width > 0 and polygon.hole_height > 0:
- mask.ctx.set_operator(cairo.OPERATOR_CLEAR
- if polygon.level_polarity == 'dark'
- and (not self.invert)
- else cairo.OPERATOR_OVER)
- width, height = self.scale_point((polygon.hole_width, polygon.hole_height))
- lower_left = rotate_point((center[0] - width / 2.0, center[1] - height / 2.0),
- polygon.rotation, center)
- lower_right = rotate_point((center[0] + width / 2.0, center[1] - height / 2.0),
- polygon.rotation, center)
- upper_left = rotate_point((center[0] - width / 2.0, center[1] + height / 2.0),
- polygon.rotation, center)
- upper_right = rotate_point((center[0] + width / 2.0, center[1] + height / 2.0),
- polygon.rotation, center)
- points = (lower_left, lower_right, upper_right, upper_left)
- mask.ctx.move_to(*points[-1])
- for point in points:
- mask.ctx.line_to(*point)
- mask.ctx.fill()
-
- self.ctx.mask_surface(mask.surface, self.origin_in_pixels[0])
-
- def _render_drill(self, circle, color=None):
- color = color if color is not None else self.drill_color
- self._render_circle(circle, color)
-
- def _render_slot(self, slot, color):
- start = map(mul, slot.start, self.scale)
- end = map(mul, slot.end, self.scale)
-
- width = slot.diameter
-
- self.ctx.set_operator(cairo.OPERATOR_OVER
- if slot.level_polarity == 'dark' and
- (not self.invert) else cairo.OPERATOR_CLEAR)
- with self._clip_primitive(slot):
- with self._new_mask() as mask:
- mask.ctx.set_line_width(width * self.scale[0])
- mask.ctx.set_line_cap(cairo.LINE_CAP_ROUND)
- mask.ctx.move_to(*start)
- mask.ctx.line_to(*end)
- mask.ctx.stroke()
- self.ctx.mask_surface(mask.surface, self.origin_in_pixels[0])
-
- def _render_amgroup(self, amgroup, color):
- # Since holes/clear areas in the mask group must be drawn as clear, we need to render the primitives of this
- # group into a mask context first, then composite this mask context on top of our output surface. This means
- # that a clear primitive inside the group will cover/draw over dark primitives inside the group, but it will
- # *not* cover/draw over dark primitives outside the group.
-
- mask_surface = cairo.SVGSurface(None, self.size_in_pixels[0], self.size_in_pixels[1])
- mask_ctx = cairo.Context(mask_surface)
- mask_ctx.set_matrix(self.ctx.get_matrix())
-
- old_surface, self.surface = self.surface, mask_surface
- old_ctx, self.ctx = self.ctx, mask_ctx
-
- for primitive in amgroup.primitives:
- self.render(primitive)
-
- old_ctx.mask_surface(mask_surface, self.origin_in_pixels[0])
- mask_surface.finish()
- self.surface, self.ctx = old_surface, old_ctx
-
- def _render_test_record(self, primitive, color):
- position = [pos + origin for pos, origin in
- zip(primitive.position, self.origin_in_inch)]
- self.ctx.select_font_face(
- 'monospace', cairo.FONT_SLANT_NORMAL, cairo.FONT_WEIGHT_BOLD)
- self.ctx.set_font_size(13)
- self._render_circle(Circle(position, 0.015), color)
- self.ctx.set_operator(cairo.OPERATOR_OVER
- if primitive.level_polarity == 'dark' and
- (not self.invert) else cairo.OPERATOR_CLEAR)
- self.ctx.move_to(*[self.scale[0] * (coord + 0.015) for coord in position])
- self.ctx.scale(1, -1)
- self.ctx.show_text(primitive.net_name)
- self.ctx.scale(1, -1)
-
- def new_render_layer(self, color=None, mirror=False):
- size_in_pixels = self.scale_point(self.size_in_inch)
- m = self._xform_matrix
- matrix = cairo.Matrix(m.xx, m.yx, m.xy, m.yy, m.x0, m.y0)
- layer = cairo.SVGSurface(None, size_in_pixels[0], size_in_pixels[1])
- ctx = cairo.Context(layer)
-
- if self.invert:
- ctx.set_source_rgba(0.0, 0.0, 0.0, 1.0)
- ctx.set_operator(cairo.OPERATOR_OVER)
- ctx.paint()
- if mirror:
- matrix.xx = -1.0
- matrix.x0 = self.origin_in_pixels[0] + self.size_in_pixels[0]
- self.ctx = ctx
- self.ctx.set_matrix(matrix)
- self.active_layer = layer
- self.active_matrix = matrix
-
- def flatten(self, color=None, alpha=None):
- color = color if color is not None else self.color
- alpha = alpha if alpha is not None else self.alpha
- self.output_ctx.set_source_rgba(color[0], color[1], color[2], alpha)
- self.output_ctx.mask_surface(self.active_layer)
- self.ctx = None
- self.active_layer = None
- self.active_matrix = None
-
- def paint_background(self, settings=None):
- color = settings.color if settings is not None else self.background_color
- alpha = settings.alpha if settings is not None else 1.0
- if not self.has_bg:
- self.has_bg = True
- self.output_ctx.set_source_rgba(color[0], color[1], color[2], alpha)
- self.output_ctx.paint()
-
- def _clip_primitive(self, primitive):
- """ Clip rendering context to pixel-aligned bounding box
-
- Calculates pixel- and axis- aligned bounding box, and clips current
- context to that region. Improves rendering speed significantly. This
- returns a context manager, use as follows:
-
- with self._clip_primitive(some_primitive):
- do_rendering_stuff()
- do_more_rendering stuff(with, arguments)
-
- The context manager will reset the context's clipping region when it
- goes out of scope.
-
- """
- class Clip:
- def __init__(clp, primitive):
- (xmin, ymin), (xmax, ymax) = primitive.bounding_box
-
- # Round bounds to the nearest pixel outside of the primitive
- clp.xmin = math.floor(self.scale[0] * xmin)
- clp.xmax = math.ceil(self.scale[0] * xmax)
-
- # We need to offset Y to take care of the difference in y-pos
- # caused by flipping the axis.
- clp.ymin = math.floor(
- (self.scale[1] * ymin) - math.ceil(self.origin_in_pixels[1]))
- clp.ymax = math.ceil(
- (self.scale[1] * ymax) - math.floor(self.origin_in_pixels[1]))
-
- # Calculate width and height, rounded to the nearest pixel
- clp.width = abs(clp.xmax - clp.xmin)
- clp.height = abs(clp.ymax - clp.ymin)
-
- def __enter__(clp):
- # Clip current context to primitive's bounding box
- self.ctx.rectangle(clp.xmin, clp.ymin, clp.width, clp.height)
- self.ctx.clip()
-
- def __exit__(clp, exc_type, exc_val, traceback):
- # Reset context clip region
- self.ctx.reset_clip()
-
- return Clip(primitive)
-
- def scale_point(self, point):
- return tuple([coord * scale for coord, scale in zip(point, self.scale)])