def _draw_stroke(self, ctx: Context, geom: Union[Polygon, MultiPolygon]):
     if isinstance(geom, MultiPolygon):
         for sub_geom in geom.geoms:
             self._draw_stroke(ctx, sub_geom)
         return
     CairoHelper.draw_polygon(ctx, geom)
     ctx.stroke()
示例#2
0
文件: cairo.py 项目: draustin/otk
def _(d: Line, ctx: cairo.Context, scale: float):
    ctx.save()
    ctx.move_to(d.x0 * scale, d.y0 * scale)
    ctx.line_to(d.x1 * scale, d.y1 * scale)
    ctx.stroke()
    # ctx.fill()
    ctx.restore()
示例#3
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    def paint_foreground(self, ctx: Context):
        if self.border_corner:
            draw_rounded_rectangle(ctx, Rectangle(ZERO_TOP_LEFT, self.size), self.border_corner)
            ctx.clip()

        self.paint_scale_background(ctx)

        if self.values:
            pos = 0.0
            for value in self.values:
                l_pos = pos
                pos += value[0] / self._total
                if value[1]:
                    ctx.set_source_rgba(*value[1])
                    if self.orientation == BarWidget.Orientation.HORIZONTAL_LEFT_TO_RIGHT:
                        ctx.rectangle(l_pos * self.width, 0, (pos - l_pos) * self.width, self.height)
                    elif self.orientation == BarWidget.Orientation.HORIZONTAL_RIGHT_TO_LEFT:
                        ctx.rectangle(self.width - l_pos * self.width, 0, self.width - (l_pos - pos) * self.width,
                                      self.height)
                    elif self.orientation == BarWidget.Orientation.VERTICAL_DOWN:
                        ctx.rectangle(0, l_pos * self.height, self.width, (pos - l_pos) * self.height)
                    elif self.orientation == BarWidget.Orientation.VERTICAL_UP:
                        ctx.rectangle(0, self.height - l_pos * self.height, self.width, (l_pos - pos) * self.height)
                    ctx.fill()

        self.paint_scale_foreground(ctx)

        if self.border:
            ctx.set_source_rgba(*self.border)
            ctx.set_line_width(self.border_width)
            draw_rounded_rectangle(ctx, Rectangle(ZERO_TOP_LEFT, self.size), self.border_corner)
            ctx.stroke()
    def _draw_railway(self, ctx: Context, line_string: LineString):
        CairoHelper.draw_line_string(ctx, line_string)

        # Todo: Buffer the linestring outwards
        # ShapelyHelper.buffer_linestring()

        ctx.stroke()
    def draw(self, ctx: Context, polygon: bool) -> None:
        line_width_current = self.line_width_initial

        ctx.set_source_rgb(self.color[0], self.color[1], self.color[2])

        x_start = self.position[0]
        x_end = x_start + self.target_width
        y = self.position[1]

        while ((self.line_width_check_is_greater
                and line_width_current > self.line_width_final)
               or (not self.line_width_check_is_greater
                   and line_width_current < self.line_width_final)):
            ctx.set_line_width(line_width_current)
            y += line_width_current / 2

            if polygon:
                ctx.move_to(x_start, y - line_width_current / 2)
                ctx.line_to(x_end, y - line_width_current / 2)
                ctx.line_to(x_end, y + line_width_current / 2)
                ctx.line_to(x_start, y + line_width_current / 2)
                ctx.fill()
            else:
                ctx.move_to(x_start, y)
                ctx.line_to(x_end, y)
                ctx.stroke()

            # Add the white space
            y += line_width_current

            # prepare next line width
            y += line_width_current / 2
            line_width_current += self.line_width_delta
示例#6
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def export_svg(fn, paths, size, line_with=0.1, scale_factor=None):

  from cairocffi import SVGSurface, Context
  from .ddd import spatial_sort_2d as sort

  if not scale_factor:
    scale_factor = size

  s = SVGSurface(fn, size, size)
  c = Context(s)

  c.set_line_width(0.1)

  paths = sort(paths)

  for path in paths:
    path *= scale_factor

    c.new_path()
    c.move_to(*path[0,:])
    for p in path[1:]:
      c.line_to(*p)
    c.stroke()

  c.save()
示例#7
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def coloured_bezier(ctx: cairo.Context, p0, p1, p2, p3, colors, width, detail=100, fade=None):
    p0 = np.array(p0)
    p1 = np.array(p1)
    p2 = np.array(p2)
    p3 = np.array(p3)

    bez, bezd = cubic_bezier(p0, p1, p2, p3, numpoints=detail)
    bezd = normalize(bezd, norm='l2', axis=1)
    frac_sum = -.5

    for color, frac in colors:
        (r, g, b, a) = color
        if fade is None:
            ctx.set_source_rgba(r, g, b, a)
        else:
            ctx.set_source(fade_pattern(p0[0], p0[1], p3[0], p3[1], r, g, b, a, fade))
        ctx.set_line_width(frac*width)
        frac_sum += frac/2

        ctx.move_to(bez[0][0] - width * frac_sum * bezd[0][1], bez[0][1] + width * frac_sum * bezd[0][0])
        for i in range(0, bez.shape[0] - 3, 3):
            ctx.curve_to(bez[i + 1][0] - width * frac_sum * bezd[i + 1][1], bez[i + 1][1] + width * frac_sum * bezd[i + 1][0],
                         bez[i + 2][0] - width * frac_sum * bezd[i + 2][1], bez[i + 2][1] + width * frac_sum * bezd[i + 2][0],
                         bez[i + 3][0] - width * frac_sum * bezd[i + 3][1], bez[i + 3][1] + width * frac_sum * bezd[i + 3][0])
        # for i in range(0, bez.shape[0] - 3, 2):
        #     ctx.move_to(bez[i][0] - width * frac_sum * bezd[i][1], bez[i][1] + width * frac_sum * bezd[i][0])
        #     ctx.curve_to(bez[i + 1][0] - width * frac_sum * bezd[i + 1][1], bez[i + 1][1] + width * frac_sum * bezd[i + 1][0],
        #                  bez[i + 2][0] - width * frac_sum * bezd[i + 2][1], bez[i + 2][1] + width * frac_sum * bezd[i + 2][0],
        #                  bez[i + 3][0] - width * frac_sum * bezd[i + 3][1], bez[i + 3][1] + width * frac_sum * bezd[i + 3][0])

        ctx.stroke()
        frac_sum += frac/2
示例#8
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 def _draw_stroke(self, ctx: Context, geom: Union[LineString,
                                                  MultiLineString]):
     if isinstance(geom, MultiLineString):
         for sub_geom in geom.geoms:
             self._draw_stroke(ctx, sub_geom)
         return
     CairoHelper.draw_line_string(ctx, geom)
     ctx.stroke()
示例#9
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 def draw(self, context: cairo.Context, x: float, y: float, fxy: FixXY):
     if debug:
         context.set_source_rgb(1 if self.no_page_break else 0, 0, 0)
         context.rectangle(*fxy(x - 5, y), *fxy(2, 16))
         context.fill()
         context.set_source_rgb(0.5, 0.5, 0.5)
         context.rectangle(*fxy(self.indent + x, y),
                           *fxy(self.width, self.height))
         context.stroke()
示例#10
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文件: line.py 项目: Mr-Clear/Clear19
 def paint_foreground(self, ctx: Context):
     ctx.set_line_width(self.line_width)
     if self.orientation == Line.Orientation.HORIZONTAL:
         ctx.move_to(*self.size.position(Anchor.CENTER_LEFT))
         ctx.line_to(*self.size.position(Anchor.CENTER_RIGHT))
     else:
         ctx.move_to(*self.size.position(Anchor.TOP_CENTER))
         ctx.line_to(*self.size.position(Anchor.BOTTOM_CENTER))
     ctx.stroke()
示例#11
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 def paint_scale_background(self, ctx: Context):
     cpu_count = Global.system_data.cpu_count
     for i in range(cpu_count):
         if i % 2:
             ctx.set_source_rgba(*Color.GRAY33)
         else:
             ctx.set_source_rgba(*Color.GRAY50)
         ctx.move_to(0, self.height - self.height / cpu_count * i)
         ctx.line_to(self.width, self.height - self.height / cpu_count * i)
         ctx.stroke()
示例#12
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def draw_ray_trace(r0: Sequence[float], elements: Sequence[Element],
                   ctx: cairo.Context, scale: float):
    ctx.save()
    r = r0
    for element in elements:
        ctx.move_to(0, r[0] * scale)
        ctx.translate(element.thickness * scale, 0)
        rp = element.matrix.dot(r)
        ctx.line_to(0, rp[0] * scale)
        ctx.stroke()
        r = rp
    ctx.restore()
示例#13
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    def draw(self, ctx: Context, outline: Union[Polygon, MultiPolygon]):
        if isinstance(outline, MultiPolygon):
            shadow_line_strings = []
            for sub_outline in outline.geoms:
                shadow_line_string = self.draw(ctx, sub_outline)
                shadow_line_strings.append(shadow_line_string)
            return shadow_line_strings
        buffered_outline = outline.buffer(-self.outline_line_width / 2, cap_style=3, join_style=2)

        shadow_line_strings = self._get_shadow_lines(buffered_outline)
        for shadow_line_string in shadow_line_strings:
            CairoHelper.draw_line_string(ctx, shadow_line_string)
            ctx.stroke()
        pass
示例#14
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 def paint_foreground(self, ctx: Context):
     if self._image:
         sx = self.width / self._image.get_width()
         sy = self.height / self._image.get_height()
         s = min(sx, sy)
         sw = self._image.get_width() * s
         sh = self._image.get_height() * s
         ctx.scale(s, s)
         x = 0
         y = 0
         if self.alignment == Anchor.TOP_LEFT:
             x = 0
             y = 0
         elif self.alignment == Anchor.TOP_CENTER:
             x = (self.width - sw) / 2
             y = 0
         elif self.alignment == Anchor.TOP_RIGHT:
             x = self.width - sw
             y = 0
         elif self.alignment == Anchor.CENTER_LEFT:
             x = 0
             y = (self.height - sh) / 2
         elif self.alignment == Anchor.CENTER_CENTER:
             x = (self.width - sw) / 2
             y = (self.height - sh) / 2
         elif self.alignment == Anchor.CENTER_RIGHT:
             x = (self.width - sw)
             y = (self.height - sh) / 2
         elif self.alignment == Anchor.BOTTOM_LEFT:
             x = 0
             y = self.height - sh
         elif self.alignment == Anchor.BOTTOM_CENTER:
             x = (self.width - sw) / 2
             y = self.height - sh
         elif self.alignment == Anchor.BOTTOM_RIGHT:
             x = self.width - sw
             y = self.height - sh
         x /= s
         y /= s
         ctx.set_source_surface(self._image, x, y)
         ctx.paint()
     else:
         ctx.move_to(0, 0)
         ctx.line_to(self.size.width, self.size.height)
         ctx.stroke()
         ctx.move_to(0, self.size.height)
         ctx.line_to(self.size.width, 0)
         ctx.stroke()
示例#15
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    def draw_border(
            self,
            g: Graphics,
            component: T,
            color: RGBA,
            thickness: float = GlassLookAndFeel.BorderThickness) -> None:
        area = component.bounds

        if area.width == 0 or area.height == 0:
            return

        g.set_source_rgba(color.r, color.g, color.b, color.a)
        g.set_line_width(thickness)

        self.draw_rect(g, area, 8)

        g.stroke()
示例#16
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def label_train_spaces(ctx: cairo.Context,
                       train: trains.Train,
                       radius_factors=1,
                       broken_spaces: Sequence = None):
    """Draw material name and thickness of the spaces.

    Args:
        radius_factors (scalar or sequence): Factor by which the average interface radii is multiplied to place the text. If
            a scalar is given it is broadcast.
    """
    spaces, brokens = break_spaces(train.spaces, broken_spaces)
    radius_factors = np.broadcast_to(radius_factors, (len(spaces), ))
    radius_last = train.interfaces[0].radius
    y_last = 0
    h_last = 0
    n = train.interfaces[0].n1
    for space, next_interface, radius_factor in zip(
            spaces, train.interfaces + (None, ), radius_factors):
        if next_interface is None:
            radius_next = radius_last
            h_next = 0
        else:
            radius_next = next_interface.radius
            h_next = functions.calc_sphere_sag(next_interface.roc, radius_next)
        y_next = y_last + space
        if space != 0:
            string = '%.3f mm %s' % (space * 1e3, n.name)
            radius = (radius_last + radius_next) / 2
            x = radius_factor * radius
            y = (y_next + h_next + y_last + h_last) / 2

            ctx.save()
            ctx.translate(x, y)
            ctx.show_text(string)
            ctx.new_path()
            ctx.restore()

            if radius_factor > 1:
                draw_polyline(ctx, ((radius, y), (x, y)))
                ctx.stroke()

        y_last = y_next
        h_last = h_next
        if next_interface is not None:
            n = next_interface.n2
            radius_last = next_interface.radius
示例#17
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def _show_layout_line_logical_extents(
        context: cairocffi.Context,
        layout: pangocffi.Layout
):
    layout_iter = layout.get_iter()
    context.set_line_width(0.5)
    context.set_dash([1, 1])
    alternate = True
    while True:
        alternate = not alternate
        extents = layout_iter.get_line_extents()
        context.set_source_rgba(0, 0, 1 if alternate else 0.5, 0.9)
        _rectangle_path(context, extents[1])
        context.stroke()
        _coordinate_path(context, (extents[1].x, extents[1].y))
        context.fill()

        if not layout_iter.next_run():
            break
示例#18
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def label_interface(ctx: cairo.Context,
                    face: trains.Interface,
                    radius_factor=1):
    """Draw text saying ROC, and a line from the edge of the interface to the text.

    Args:
        radius_factor (scalar): Factor by which interface radius is multiplied to get text x position.
    """
    x = radius_factor * face.radius
    y = functions.calc_sphere_sag(face.roc, face.radius)
    string = 'ROC %.3f mm' % (face.roc * 1e3)
    ctx.set_source_rgb(0, 0, 0)
    ctx.save()
    ctx.translate(x, y)
    ctx.show_text(string)
    ctx.new_path()
    ctx.restore()
    if radius_factor > 1:
        draw_polyline(ctx, ((face.radius, y), (x, y)))
        ctx.stroke()
    def draw_labels(self, ctx: Context) -> None:
        point_diameter_current = self.point_diameter_initial
        text_height_room = 0

        ctx.set_source_rgb(self.color[0], self.color[1], self.color[2])

        points_per_row = math.floor(self.target_width / self.point_margin)
        i = 0

        while ((self.point_diameter_check_is_greater
                and point_diameter_current > self.point_diameter_final)
               or (not self.point_diameter_check_is_greater
                   and point_diameter_current < self.point_diameter_final)):

            col = i % points_per_row
            row = math.floor(i / points_per_row)
            x = self.position[
                0] + col * self.point_margin + self.point_margin / 2
            y = self.position[
                1] + row * self.point_margin + self.point_margin / 2

            first_point_diameter_in_row = point_diameter_current
            last_point_diameter_in_row = point_diameter_current + self.point_diameter_delta * (
                points_per_row - 1)
            print(first_point_diameter_in_row)
            print(last_point_diameter_in_row)

            if text_height_room > 2:
                ctx.move_to(x + 0, y)
                ctx.line_to(x + 2, y)
                ctx.stroke()
                self.draw_text(
                    ctx,
                    "{0:.3f} - {1:.3f}".format(first_point_diameter_in_row,
                                               last_point_diameter_in_row) +
                    " mm", x + 3, y, 2)
                text_height_room = 0

            i += points_per_row
            point_diameter_current += self.point_diameter_delta * points_per_row
            text_height_room += self.point_margin
示例#20
0
def _show_layout_baseline(
        context: cairocffi.Context,
        layout: pangocffi.Layout
):
    layout_iter = layout.get_iter()
    context.set_line_width(0.5)
    context.set_dash([1, 1])
    while True:
        extents = layout_iter.get_line_extents()
        baseline = layout_iter.get_baseline()
        y_ranges = layout_iter.get_line_yrange()

        context.set_source_rgba(1, 0, 0, 0.9)
        context.move_to(
            pangocffi.units_to_double(extents[0].x),
            pangocffi.units_to_double(y_ranges[0])
        )
        context.line_to(
            pangocffi.units_to_double(extents[0].x + extents[0].width),
            pangocffi.units_to_double(y_ranges[0])
        )
        context.stroke()

        context.set_source_rgba(0, 1, 0, 0.9)
        context.stroke()
        context.move_to(
            pangocffi.units_to_double(extents[0].x),
            pangocffi.units_to_double(baseline)
        )
        context.line_to(
            pangocffi.units_to_double(extents[0].x + extents[0].width),
            pangocffi.units_to_double(baseline)
        )
        context.stroke()

        context.set_source_rgba(0, 0, 1, 0.9)
        context.move_to(
            pangocffi.units_to_double(extents[0].x),
            pangocffi.units_to_double(y_ranges[1])
        )
        context.line_to(
            pangocffi.units_to_double(extents[0].x + extents[0].width),
            pangocffi.units_to_double(y_ranges[1])
        )
        context.stroke()

        if not layout_iter.next_run():
            break
 def _generate_layer(self, transcription, page, layer):
     surface = PDFSurface(layer, *page.page_size)
     context = Context(surface)
     # context.select_font_face('Georgia')
     context.set_source_rgba(1, 1, 1, 1 / 256)  # almost invisible
     context.set_font_size(2)
     for line_ink, line_transcription in zip(page.lines, transcription):
         ink, transformation = writing.normalized(line_ink)
         context.save()
         context.transform(
             Matrix(*(Transformation.translation(
                 0, page.page_size[1]).parameter)))
         context.transform(Matrix(*(Transformation.mirror(0).parameter)))
         context.transform(Matrix(*((~transformation).parameter)))
         context.transform(Matrix(*(Transformation.mirror(0).parameter)))
         HANDWRITING_WIDTH = ink.boundary_box[1]
         TYPEWRITING_WIDTH = context.text_extents(line_transcription)[2]
         context.scale(HANDWRITING_WIDTH / TYPEWRITING_WIDTH, 1)
         context.move_to(0, 0)
         context.show_text(line_transcription)
         context.restore()
     context.stroke()
     context.show_page()
     surface.flush()
    def draw_labels(self, ctx: Context):
        ctx.set_line_width(0.1)

        line_width_current = self.line_width_initial
        text_height_room = 0

        ctx.set_source_rgb(self.color[0], self.color[1], self.color[2])

        x = self.position[0]
        y = self.position[1]

        while ((self.line_width_check_is_greater
                and line_width_current > self.line_width_final)
               or (not self.line_width_check_is_greater
                   and line_width_current < self.line_width_final)):
            y += line_width_current / 2
            text_height_room += line_width_current / 2

            # Draw the line annotating the row
            if text_height_room > 2:
                ctx.move_to(x + 0, y)
                ctx.line_to(x + 2, y)
                ctx.stroke()
                self.draw_text(ctx,
                               "{0:.2f}".format(line_width_current) + " mm",
                               x + 3, y, 2)
                text_height_room = 0

            # Add the white space
            y += line_width_current
            text_height_room += line_width_current

            # prepare next line width
            y += line_width_current / 2
            text_height_room += line_width_current / 2
            line_width_current += self.line_width_delta
示例#23
0
def _show_layout_y_ranges(
        context: cairocffi.Context,
        layout: pangocffi.Layout
):
    layout_iter = layout.get_iter()
    context.set_line_width(0.5)
    context.set_dash([1, 1])
    alternate = True
    while True:
        alternate = not alternate
        extents = layout_iter.get_line_extents()
        y_ranges = layout_iter.get_line_yrange()

        context.set_source_rgba(0, 0, 1 if alternate else 0.5, 0.9)
        context.move_to(
            pangocffi.units_to_double(extents[0].x),
            pangocffi.units_to_double(y_ranges[0])
        )
        context.line_to(
            pangocffi.units_to_double(extents[0].x + extents[0].width),
            pangocffi.units_to_double(y_ranges[0])
        )
        context.stroke()

        context.move_to(
            pangocffi.units_to_double(extents[0].x),
            pangocffi.units_to_double(y_ranges[1])
        )
        context.line_to(
            pangocffi.units_to_double(extents[0].x + extents[0].width),
            pangocffi.units_to_double(y_ranges[1])
        )
        context.stroke()

        if not layout_iter.next_run():
            break
    def __draw_ring (self: 'HueSatWheelWidget', cr: cairocffi.Context,
                     width: int, height: int, center_x: float, center_y: float,
                     outer: float, inner: float) -> None:
        self.__redraw = False
        stride = cairocffi.ImageSurface.format_stride_for_width (cairocffi.FORMAT_ARGB32, width)
        buf = numpy.empty (int (height * stride), dtype = numpy.uint8)

        for y in range (height):
            idx = y * width * 4

            dy = -(y - center_y)

            for x in range (width):
                dx = x - center_x

                dist = dx * dx + dy * dy

                angle = math.atan2 (dy, dx)

                if angle < 0:
                    angle += 2 * numpy.pi

                hue = angle / (2 * numpy.pi)

                hue_idx = int ((angle + 2 * numpy.pi / 3) / (2 * numpy.pi) * 255)
                hue_idx = hue_idx % 256

                if dist < ((inner - 1) ** 2) * (1 - self.__hist[255 - hue_idx]) or \
                   dist > ((outer + 1) ** 2):
                    buf[idx + 0] = 0
                    buf[idx + 1] = 0
                    buf[idx + 2] = 0
                    buf[idx + 3] = 0
                    idx += 4
                    continue

                r, g, b = colorsys.hsv_to_rgb (hue, 1.0, 1.0)
                a = 255

                buf[idx + 0] = int (math.floor (r * 255 + 0.5))
                buf[idx + 1] = int (math.floor (g * 255 + 0.5))
                buf[idx + 2] = int (math.floor (b * 255 + 0.5))
                buf[idx + 3] = a
                idx += 4

        source = cairocffi.ImageSurface.create_for_data (
            memoryview (buf), cairocffi.FORMAT_ARGB32, width, height, stride
        )

        fg_color = self.get_style_context ().get_color (Gtk.StateFlags.NORMAL)

        cr.save ()

        cr.set_source_rgba (0, 0, 0, 0)
        cr.paint ()

        cr.set_source_surface (source, 0, 0)
        cr.paint ()

        cr.set_line_width (1)
        cr.new_path ()
        cr.set_source_rgba (*list (fg_color))

        cr.arc (center_x, center_y, (self.size - 4) / 2. - self.ring_width,
                0, 2 * numpy.pi)
        cr.stroke ()

        cr.arc (center_x, center_y, (self.size - 2) / 2, 0, 2 * numpy.pi)
        cr.stroke ()

        cr.arc (center_x, center_y, 5, 0, 2 * numpy.pi)
        cr.fill ()

        cr.restore ()
    def _draw_water(self, ctx: Context, outline: Union[Polygon, MultiPolygon]):
        # Draw outline of ripple
        CairoHelper.draw_polygon(ctx, outline)
        ctx.stroke()

        self._draw_ripples(ctx, outline)
示例#26
0
文件: cairo.py 项目: draustin/otk
def _(d: Arc, ctx: cairo.Context, scale: float):
    ctx.save()
    ctx.arc(d.xc * scale, d.yc * scale, d.radius * scale, d.theta0, d.theta1)
    ctx.stroke()
    ctx.restore()
示例#27
0
                y = mean_pin_y - label_height // 2
                print(f"{text=}\t{y=}")

                if pass_ == 0:
                    ctx.set_source_rgba(*color, 1)
                    draw_rounded_rectangle(ctx, x, y, label_width,
                                           label_height, label_radius)
                    ctx.fill()

                    for pin_name in pin_names:
                        pin_x, pin_y, align = pin_defs[pin_name]
                        pin_x = pin_x * w
                        pin_y = pin_y * h_bg - h_bg * y_offset

                        ctx.move_to(line_origin_x, y + label_height // 2)
                        ctx.line_to(w * pad_sides + pin_x, pin_y)
                        ctx.set_line_width(4)
                        ctx.stroke()
                else:
                    ctx.move_to(x + label_pad[0] - x_bearing,
                                y - y_bearing + label_pad[1])
                    ctx.set_source_rgb(1, 1, 1)
                    ctx.show_text(text)

        # save to file
        canvas.write_to_png(f"{board_name}_{variant_name}.png")

        # stride = ImageSurface.format_stride_for_width(format, width)
        # data = bytearray(stride * height)
        # surface = ImageSurface(format, width, height, data, stride)
 def _draw_wall(self, ctx: Context, line_string: LineString):
     CairoHelper.draw_line_string(ctx, line_string)
     ctx.stroke()
示例#29
0
def make_interface(ctx: cairo.Context, face: trains.Interface, num_points=32):
    draw_polyline(ctx, face.get_points(num_points))
    ctx.stroke()
 def _draw_ripple(self, ctx: Context, ripple: Polygon, iteration: int):
     CairoHelper.draw_polygon(ctx, ripple)
     ctx.stroke()