1 files changed, 470 insertions, 0 deletions
diff --git a/gerbolyze/__init__.py b/gerbolyze/__init__.py
new file mode 100755
index 0000000..e9e7e5f
--- /dev/null
+++ b/gerbolyze/__init__.py
@@ -0,0 +1,470 @@
+import tempfile
+import os.path as path
+from pathlib import Path
+import textwrap
+import subprocess
+import functools
+import os
+import base64
+import re
+import sys
+import warnings
+import shutil
+from zipfile import ZipFile, is_zipfile
+
+from lxml import etree
+import numpy as np
+import click
+
+import gerbonara as gn
+
+@click.group()
+def cli():
+    pass
+
+@cli.command()
+@click.argument('input_gerbers', type=click.Path(exists=True))
+@click.argument('input_svg', type=click.Path(exists=True, dir_okay=False, file_okay=True, allow_dash=True))
+@click.argument('output_gerbers')
+@click.option('--dilate', default=0.1, type=float, help='Default dilation for subtraction operations in mm')
+@click.option('--curve-tolerance', type=float, help='Tolerance for curve flattening in mm')
+@click.option('--no-subtract', 'no_subtract', flag_value=True, help='Disable subtraction')
+@click.option('--subtract', help='Use user subtraction script from argument (see description above)')
+@click.option('--trace-space', type=float, default=0.1, help='passed through to svg-flatten')
+@click.option('--vectorizer', help='passed through to svg-flatten')
+@click.option('--vectorizer-map', help='passed through to svg-flatten')
+@click.option('--preserve-aspect-ratio', help='PNG/JPG files only: passed through to svg-flatten')
+@click.option('--exclude-groups', help='passed through to svg-flatten')
+def paste(input_gerbers, input_svg, output_gerbers,
+        dilate, curve_tolerance, no_subtract, subtract,
+        preserve_aspect_ratio,
+        trace_space, vectorizer, vectorizer_map, exclude_groups):
+    """ Render vector data and raster images from SVG file into gerbers. """
+
+    if no_subtract:
+        subtract_map = {}
+    else:
+        subtract_map = parse_subtract_script(subtract, dilate)
+
+    output_gerbers = Path(output_gerbers)
+    input_gerbers = Path(input_gerbers)
+    stack = gn.LayerStack.open(input_gerbers, lazy=True)
+    (bb_min_x, bb_min_y), (bb_max_x, bb_max_y) = bounds = stack.board_bounds()
+
+    # Create output dir if it does not exist yet. Do this now so we fail early
+    if input_gerbers.is_dir():
+        output_gerbers.mkdir(exist_ok=True)
+
+        # In case output dir already existed, remove files we will overwrite
+        for in_file in input_gerbers.iterdir():
+            out_cand = output_gerbers / in_file.name
+            out_cand.unlink(missing_ok=True)
+
+    else: # We are working on a zip file
+        tempdir = tempfile.NamedTemporaryDirectory()
+
+    @functools.lru_cache()
+    def do_dilate(layer, amount):
+        return dilate_gerber(layer, bounds, amount, curve_tolerance)
+    
+    for (side, use), layer in stack.graphic_layers.items():
+        print('processing', side, use, 'layer')
+        overlay_grb = svg_to_gerber(input_svg,
+                trace_space=trace_space, vectorizer=vectorizer, vectorizer_map=vectorizer_map,
+                exclude_groups=exclude_groups, curve_tolerance=curve_tolerance,
+                preserve_aspect_ratio=preserve_aspect_ratio,
+                only_groups=f'g-{side}-{use}')
+        # FIXME outline mode, also process outline layer
+
+        if not overlay_grb:
+            print(f'Overlay {side} {use} layer is empty. Skipping.', file=sys.stderr)
+            continue
+
+        # only open lazily loaded layer if we need it. Replace lazy wrapper in stack with loaded layer.
+        stack.graphic_layers[(side, use)] = layer = layer.instance
+
+        # move overlay from svg origin to gerber origin
+        overlay_grb.offset(bb_min_x, bb_min_y)
+
+        print('compositing')
+        # dilated subtract layers on top of overlay
+        if side in ('top', 'bottom'): # do not process subtraction scripts for inner layers
+            dilations = subtract_map.get(use, [])
+            for d_layer, amount in dilations:
+                print('processing dilation', d_layer, amount)
+                dilated = do_dilate(stack[(side, d_layer)], amount)
+                layer.merge(dilated, mode='below', keep_settings=True)
+
+        # overlay on bottom
+        layer.merge(overlay_grb, mode='below', keep_settings=True)
+
+    if input_gerbers.is_dir():
+        stack.save_to_directory(output_gerbers)
+    else:
+        stack.save_to_zipfile(output_gerbers)
+
+@cli.command()
+@click.argument('input_gerbers', type=click.Path(exists=True))
+@click.argument('output_svg', required=False)
+@click.option('-t' ,'--top', help='Render board top side.', is_flag=True)
+@click.option('-b' ,'--bottom', help='Render board bottom side.', is_flag=True)
+@click.option('-f' ,'--force', help='Overwrite existing output file when autogenerating file name.', is_flag=True)
+@click.option('--vector/--raster', help='Embed preview renders into output file as SVG vector graphics instead of rendering them to PNG bitmaps. The resulting preview may slow down your SVG editor.')
+@click.option('--raster-dpi', type=float, default=300.0, help='DPI for rastering preview')
+def template(input_gerbers, output_svg, top, bottom, force, vector, raster_dpi):
+    ''' Generate SVG template for gerbolyze paste from gerber files.
+
+    INPUT may be a gerber file, directory of gerber files or zip file with gerber files
+    '''
+    source = Path(input_gerbers)
+    ttype = 'top' if top else 'bottom'
+
+    if (bool(top) + bool(bottom))  != 1:
+        raise click.UsageError('Excactly one of --top or --bottom must be given.')
+
+    if output_svg is None:
+        # autogenerate output file name if none is given:
+        # /path/to/gerber/dir -> /path/to/gerber/dir.preview-{top|bottom}.svg
+        # /path/to/gerbers.zip -> /path/to/gerbers.zip.preview-{top|bottom}.svg
+        # /path/to/single/file.grb -> /path/to/single/file.grb.preview-{top|bottom}.svg
+    
+        output_svg = source.parent / f'{source.name}.template-{ttype}.svg'
+        click.echo(f'Writing output to {output_svg}')
+
+        if output_svg.exists() and not force:
+            raise UsageError(f'Autogenerated output file already exists. Please remote first, or use --force, or '
+                    'explicitly give an output path.')
+
+    else:
+        output_svg = Path(output_svg)
+
+    stack = gn.LayerStack.open(source, lazy=True)
+    bounds = stack.board_bounds()
+    svg = str(stack.to_pretty_svg(side=('top' if top else 'bottom'), force_bounds=bounds))
+
+    template_layers = [ f'{ttype}-{use}' for use in [ 'copper', 'mask', 'silk' ] ]
+    silk = template_layers[-1]
+
+    if vector:
+        # All gerbonara SVG is in MM by default
+        output_svg.write_text(create_template_from_svg(bounds, svg, template_layers, current_layer=silk))
+
+    else:
+        with tempfile.NamedTemporaryFile(suffix='.svg') as temp_svg, \
+            tempfile.NamedTemporaryFile(suffix='.png') as temp_png:
+            Path(temp_svg.name).write_text(svg)
+            run_resvg(temp_svg.name, temp_png.name, dpi=f'{raster_dpi:.0f}')
+            output_svg.write_text(template_svg_for_png(bounds, Path(temp_png.name).read_bytes(),
+                template_layers, current_layer=silk))
+
+
+# Subtraction script handling
+#============================
+
+DEFAULT_SUB_SCRIPT = '''
+out.silk -= in.mask
+out.silk -= in.silk+0.5
+out.mask -= in.mask+0.5
+out.copper -= in.copper+0.5
+'''
+
+def parse_subtract_script(script, default_dilation=0.1):
+    if script is None:
+        script = DEFAULT_SUB_SCRIPT
+
+    subtract_script = {}
+    lines = script.replace(';', '\n').splitlines()
+    for line in lines:
+        line = line.strip()
+        if not line or line.startswith('#'):
+            continue
+
+        line = line.lower()
+        line = re.sub('\s', '', line)
+
+        # out.copper -= in.copper+0.1
+        varname = r'([a-z]+\.[a-z]+)'
+        floatnum = r'([+-][.0-9]+)'
+        match = re.fullmatch(fr'{varname}-={varname}{floatnum}?', line)
+        if not match:
+            raise ValueError(f'Cannot parse line: {line}')
+        
+        out_var, in_var, dilation = match.groups()
+        if not out_var.startswith('out.') or not in_var.startswith('in.'):
+            raise ValueError('All left-hand side values must be outputs, right-hand side values must be inputs.')
+
+        _out, _, out_layer = out_var.partition('.')
+        _in, _, in_layer = in_var.partition('.')
+
+        dilation = float(dilation) if dilation else default_dilation
+
+        subtract_script[out_layer] = subtract_script.get(out_layer, []) + [(in_layer, dilation)]
+    return subtract_script
+
+# Parameter parsing foo
+#======================
+
+def parse_bbox(bbox):
+    if not bbox:
+        return None
+    elems = [ int(elem) for elem in re.split('[,/ ]', bbox) ]
+    if len(elems) not in (2, 4):
+        raise click.BadParameter(
+                '--bbox must be either two floating-point values like: w,h or four like: x,y,w,h')
+
+    elems = [ float(e) for e in elems ]
+
+    if len(elems) == 2:
+        bounds = [0, 0, *elems]
+    else:
+        bounds = elems
+    
+    # now transform bounds to the format pcb-tools uses. Instead of (x, y, w, h) or even (x1, y1, x2, y2), that
+    # is ((x1, x2), (y1, y2)
+
+    x, y, w, h = bounds
+    return ((x, x+w), (y, y+h))
+
+def bounds_from_outline(layers):
+    ''' NOTE: When the user has not set explicit bounds, we automatically extract the design's bounding box from the
+    input gerber files. If a folder is used as input, we use the outline gerber and barf if we can't find one. If only a
+    single file is given, we simply use that file's bounding box
+    
+    We have to do things this way since gerber files do not have explicit bounds listed.
+    
+    Note that the bounding box extracted from the outline layer usually will be one outline layer stroke widht larger in
+    all directions than the finished board. 
+    '''
+    if 'outline' in layers:
+        outline_files = layers['outline']
+        _path, grb = outline_files[0]
+        return calculate_apertureless_bounding_box(grb.cam_source)
+
+    elif len(layers) == 1:
+        first_layer, *rest = layers.values()
+        first_file, *rest = first_layer
+        _path, grb = first_file
+        return grb.cam_source.bounding_box
+
+    else:
+        raise click.UsageError('Cannot find an outline file and no --bbox given.')
+
+def get_bounds(bbox, layers):
+    bounds = parse_bbox(bbox)
+    if bounds:
+        return bounds
+    return bounds_from_outline(layers)
+
+# Utility foo
+# ===========
+
+def run_resvg(input_file, output_file, **resvg_args):
+
+    args = []
+    for key, value in resvg_args.items():
+        if value is not None:
+            if value is False:
+                continue
+
+            args.append(f'--{key.replace("_", "-")}')
+
+            if value is not True:
+                args.append(value)
+
+    args += [input_file, output_file]
+
+    # By default, try a number of options:
+    candidates = [
+        # somewhere in $PATH
+        'resvg',
+        'wasi-resvg',
+        # in user-local cargo installation
+        Path.home() / '.cargo' / 'bin' / 'resvg',
+        # wasi-resvg in user-local pip installation
+        Path.home() / '.local' / 'bin' / 'wasi-resvg',
+        # next to our current python interpreter (e.g. in virtualenv)
+        str(Path(sys.executable).parent / 'wasi-resvg')
+        ]
+
+    # if RESVG envvar is set, try that first.
+    if 'RESVG' in os.environ:
+        exec_candidates = [os.environ['RESVG'], *exec_candidates]
+
+    for candidate in candidates:
+        try:
+            res = subprocess.run([candidate, *args], check=True)
+            print('used resvg:', candidate)
+            break
+        except FileNotFoundError:
+            continue
+    else:
+        raise SystemError('resvg executable not found')
+
+
+
+def calculate_apertureless_bounding_box(cam):
+    ''' pcb-tools'es default bounding box function returns the bounding box of the primitives including apertures (i.e.
+    line widths). For determining a board's size from the outline layer, we want the bounding box disregarding
+    apertures.
+    '''
+
+    min_x = min_y = 1000000
+    max_x = max_y = -1000000
+
+    for prim in cam.primitives:
+        bounds = prim.bounding_box_no_aperture
+        min_x = min(bounds[0][0], min_x)
+        max_x = max(bounds[0][1], max_x)
+
+        min_y = min(bounds[1][0], min_y)
+        max_y = max(bounds[1][1], max_y)
+
+    return ((min_x, max_x), (min_y, max_y))
+
+# SVG export
+#===========
+
+def template_layer(name):
+    return f'<g id="g-{name.lower()}" inkscape:label="{name}" inkscape:groupmode="layer"></g>'
+
+def template_svg_for_png(bounds, png_data, extra_layers, current_layer):
+    (x1, y1), (x2, y2) = bounds
+    w_mm, h_mm = (x2 - x1), (y2 - y1)
+
+    extra_layers = "\n  ".join(template_layer(name) for name in extra_layers)
+
+    # we set up the viewport such that document dimensions = document units = mm
+    template = f'''<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+        <svg version="1.1"
+           xmlns="http://www.w3.org/2000/svg"
+           xmlns:xlink="http://www.w3.org/1999/xlink"
+           xmlns:inkscape="http://www.inkscape.org/namespaces/inkscape"
+           xmlns:sodipodi="http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd"
+           width="{w_mm}mm" height="{h_mm}mm" viewBox="0 0 {w_mm} {h_mm}" >
+          <defs/>
+          <sodipodi:namedview inkscape:current-layer="g-{current_layer.lower()}" />
+          <g inkscape:label="Preview" inkscape:groupmode="layer" id="g-preview" sodipodi:insensitive="true" style="opacity:0.5">
+            <image x="0" y="0" width="{w_mm}" height="{h_mm}"
+               xlink:href="data:image/jpeg;base64,{base64.b64encode(png_data).decode()}" />
+          </g>
+          {extra_layers}
+        </svg>
+        '''
+    return textwrap.dedent(template)
+
+# this is fixed, we cannot tell cairo-svg to use some other value. we just have to work around it.
+CAIRO_SVG_HARDCODED_DPI = 72.0
+MM_PER_INCH = 25.4
+
+def svg_pt_to_mm(pt_len, dpi=CAIRO_SVG_HARDCODED_DPI):
+    if pt_len.endswith('pt'):
+        pt_len = pt_len[:-2]
+
+    return f'{float(pt_len) / dpi * MM_PER_INCH}mm'
+
+def create_template_from_svg(bounds, svg_data, extra_layers):
+    svg = etree.fromstring(svg_data)
+
+    # add inkscape namespaces
+    SVG_NS = '{http://www.w3.org/2000/svg}'
+    INKSCAPE_NS = 'http://www.inkscape.org/namespaces/inkscape'
+    SODIPODI_NS = 'http://sodipodi.sourceforge.net/DTD/sodipodi-0.dtd'
+    # glObAL stAtE YaY
+    etree.register_namespace('inkscape', INKSCAPE_NS)
+    etree.register_namespace('sodipodi', SODIPODI_NS)
+    INKSCAPE_NS = '{'+INKSCAPE_NS+'}'
+    SODIPODI_NS = '{'+SODIPODI_NS+'}'
+
+    # convert document units to mm
+    svg.set('width', svg_pt_to_mm(svg.get('width')))
+    svg.set('height', svg_pt_to_mm(svg.get('height')))
+
+    # add inkscape <namedview> elem to set currently selected layer
+    namedview_elem = etree.SubElement(svg, SODIPODI_NS+'namedview')
+    namedview_elem.set('id', "namedview23")
+    namedview_elem.set(INKSCAPE_NS+'current-layer', f'g-{current_layer}')
+
+    # make original group an inkscape layer
+    orig_g = svg.find(SVG_NS+'g')
+    orig_g.set('id', 'g-preview')
+    orig_g.set(INKSCAPE_NS+'label', 'Preview')
+    orig_g.set(SODIPODI_NS+'insensitive', 'true') # lock group
+    orig_g.set('style', 'opacity:0.5')
+
+    # add layers
+    for layer in extra_layers:
+        new_g = etree.SubElement(svg, SVG_NS+'g')
+        new_g.set('id', f'g-{layer.lower()}')
+        new_g.set(INKSCAPE_NS+'label', layer)
+        new_g.set(INKSCAPE_NS+'groupmode', 'layer')
+
+    return etree.tostring(svg)
+
+# SVG/gerber import
+#==================
+
+def dilate_gerber(layer, bounds, dilation, curve_tolerance):
+    with tempfile.NamedTemporaryFile(suffix='.svg') as temp_svg:
+        Path(temp_svg.name).write_text(str(layer.instance.to_svg(force_bounds=bounds, fg='white')))
+
+        (bb_min_x, bb_min_y), (bb_max_x, bb_max_y) = bounds
+        # dilate & render back to gerber
+        # NOTE: Maybe reconsider or nicely document dilation semantics ; It is weird that negative dilations affect
+        # clear color and positive affects dark colors
+        out = svg_to_gerber(temp_svg.name, dilate=-dilation, curve_tolerance=curve_tolerance)
+        return out
+
+def svg_to_gerber(infile, outline_mode=False, **kwargs):
+    infile = Path(infile)
+
+    args = [ '--format', ('gerber-outline' if outline_mode else 'gerber'),
+            '--precision', '6', # intermediate file, use higher than necessary precision
+            ]
+    
+    for k, v in kwargs.items():
+        if v is not None:
+            args.append('--' + k.replace('_', '-'))
+            if not isinstance(v, bool):
+                args.append(str(v))
+
+    with tempfile.NamedTemporaryFile(suffix='.gbr') as temp_gbr:
+        args += [str(infile), str(temp_gbr.name)]
+
+        if 'SVG_FLATTEN' in os.environ:
+            print('svg-flatten args:', args)
+            subprocess.run([os.environ['SVG_FLATTEN'], *args], check=True)
+            print('used svg-flatten at $SVG_FLATTEN')
+
+        else:
+            # By default, try four options:
+            for candidate in [
+                    # somewhere in $PATH
+                    'svg-flatten',
+                    'wasi-svg-flatten',
+
+                    # in user-local pip installation
+                    Path.home() / '.local' / 'bin' / 'svg-flatten',
+                    Path.home() / '.local' / 'bin' / 'wasi-svg-flatten',
+
+                    # next to our current python interpreter (e.g. in virtualenv)
+                    str(Path(sys.executable).parent / 'svg-flatten'),
+                    str(Path(sys.executable).parent / 'wasi-svg-flatten'),
+
+                    # next to this python source file in the development repo
+                    str(Path(__file__).parent.parent / 'svg-flatten' / 'build' / 'svg-flatten') ]:
+
+                try:
+                    subprocess.run([candidate, *args], check=True)
+                    print('used svg-flatten at', candidate)
+                    break
+                except FileNotFoundError:
+                    continue
+
+            else:
+                raise SystemError('svg-flatten executable not found')
+
+        return gn.rs274x.GerberFile.open(temp_gbr.name)
+    
+
+if __name__ == '__main__':
+    cli()