Merge pull request #8 from creativecommons/genicons

Genicons

Author: TimidRobot

.gitignore

@@ -0,0 +1,2 @@
+# Vim
+*.swp

README.md

@@ -5,3 +5,38 @@ Creative Commons badges, license Buttons, etc. (<https://licensebuttons.net/>).
 
 :warning: **Consolidation/Update in progress. This repository is in a state of
 flux.**
+
+
+## genicons.py
+
+This is a script to generate Creative Commons icon badges in png format in a
+variety of color schemes. These icons can then be served by a web server. It is
+located at [`scripts/genicons.py`](scripts/genicons.py).
+
+
+### Install
+
+1. Assuming the repository is on Debian
+2. Install required Python 2 packages:
+
+    ```shell
+    sudo apt-get install python-cairo python-gtk2
+    ```
+
+3. Install CC Icons font
+
+    ```shell
+    mkdir -p ~/.fonts
+    ln -sf ${PWD}/www/cc-icons.ttf ~/.fonts/
+    ```
+
+
+### Usage
+
+Execute with Python 2:
+
+```shell
+python genicons.py
+```
+
+This will generate the icons in the directory `www/i` directory.

scripts/genicons.py

@@ -0,0 +1,192 @@
+# genicons.py - generate all the icons.
+# Copyright 2016 Creative Commons Corporation.
+
+# Standard library
+import errno
+import math
+import os
+import os.path
+
+# Third-party
+import cairo
+import pangocairo
+
+
+SUITES = {
+    "l": {
+        "by": ["b"],
+        "by-nc": ["bn", "be", "by"],
+        "by-nd": ["bd"],
+        "by-sa": ["ba"],
+        "by-nc-nd": ["bnd", "bed", "byd"],
+        "by-nc-sa": ["bna", "bea", "bya"],
+    },
+    "p": {"cc-zero": ["0"], "public-domain-mark": ["p"]},
+}
+
+DIMENSIONS = ((88, 31, 31, 1), (80, 15, 15, 4), (76, 22, 22, 1))
+
+BACKGROUNDS = (
+    "transparent",
+    "000000",
+    # Bootstrap well grey
+    "eeeeee",
+    "ffffff",
+)
+
+STEPS = ["00", "11", "22", "33", "66", "99", "ff"]
+
+FOREGROUNDS = [
+    "%s%s%s" % (r, g, b) for r in STEPS for g in STEPS for b in STEPS
+]
+
+HEX_TO_FLOAT = 1.0 / 255.0
+
+
+def hexToFloat(digits):
+    return HEX_TO_FLOAT * int(digits, 16)
+
+
+def setColor(ctx, color_string):
+    if color_string == "transparent":
+        ctx.set_source_rgba(0.0, 0.0, 0.0, 0.0)
+    else:
+        ctx.set_source_rgb(
+            hexToFloat(color_string[0:2]),
+            hexToFloat(color_string[2:4]),
+            hexToFloat(color_string[4:6]),
+        )
+
+
+def sizeChars(ctx, chars):
+    # x, y, width, height, dx, dy
+    return [ctx.text_extents(char) for char in chars]
+
+
+def showChars(ctx, chars, foreground, padding, width, height):
+    sizes = sizeChars(ctx, chars)
+    total_padding = padding * (len(chars) - 1)
+    total_width = reduce(lambda x, y: y[3] + x, sizes, 0.0)
+    x = 0.5 + math.ceil((width / 2) - ((total_width + total_padding) / 2))
+    y = math.ceil(height / 2) + math.floor(sizes[0][3] / 2)
+    setColor(ctx, foreground)
+    for char, size in zip(chars, sizes):
+        ctx.move_to(math.ceil(x), math.ceil(y))
+        ctx.show_text(char)
+        x += size[2] + padding
+    ctx.stroke()
+
+
+def createContext(width, height):
+    surface = cairo.ImageSurface(cairo.FORMAT_ARGB32, width, height)
+    context = cairo.Context(surface)
+    ctx = pangocairo.CairoContext(context)
+    return ctx
+
+
+def setBackground(ctx, background, width, height):
+    setColor(ctx, background)
+    ctx.rectangle(0, 0, width, height)
+    ctx.fill()
+
+
+def configureFont(ctx, size):
+    ctx.select_font_face("CC Icons")
+    ctx.set_font_size(size)
+
+
+def iconFilename(dimensions, characters):
+    filename = "%ix%i" % (dimensions[0], dimensions[1])
+    if "y" in characters:
+        filename += "-y"
+    elif "e" in characters:
+        filename += "-e"
+    return filename + ".png"
+
+
+def iconPath(suite, descriptor, background, foreground):
+    foreground_path = os.path.join(
+        foreground[0:2], foreground[2:4], foreground[4:6]
+    )
+    return os.path.join(suite, descriptor, background, foreground_path)
+
+
+def genicon(
+    suite,
+    characters,
+    font_size,
+    padding,
+    width,
+    height,
+    background,
+    foreground,
+):
+    ctx = createContext(width, height)
+    setBackground(ctx, background, width, height)
+    configureFont(ctx, font_size)
+    showChars(ctx, characters, foreground, padding, width, height)
+    return ctx
+
+
+font_map = pangocairo.cairo_font_map_get_default()
+font_families = [family.get_name() for family in font_map.list_families()]
+if "CC Icons" not in font_families:
+    raise Exception(
+        "CC Icons font not installed. See" " <https://wiki.debian.org/Fonts>."
+    )
+
+script_dir = os.path.dirname(__file__)
+basedir = os.path.realpath(
+    os.path.abspath(os.path.join(script_dir, "..", "www", "i"))
+)
+print "# basedir:", basedir
+
+for suite, licenses in SUITES.iteritems():
+    for lic, module_chars in licenses.iteritems():
+        for chars in module_chars:
+            for dimensions in DIMENSIONS:
+                for background in BACKGROUNDS:
+                    for foreground in FOREGROUNDS:
+                        # e.g. white on white
+                        if foreground == background:
+                            continue
+                        path = os.path.realpath(
+                            os.path.abspath(
+                                os.path.join(
+                                    basedir,
+                                    iconPath(
+                                        suite, lic, background, foreground
+                                    ),
+                                )
+                            )
+                        )
+                        filepath = os.path.realpath(
+                            os.path.abspath(
+                                os.path.join(
+                                    path, iconFilename(dimensions, chars)
+                                )
+                            )
+                        )
+                        if os.path.exists(filepath):
+                            continue
+                        width = dimensions[0]
+                        height = dimensions[1]
+                        font_size = dimensions[2]
+                        padding = dimensions[3]
+                        ctx = genicon(
+                            suite,
+                            chars,
+                            font_size,
+                            padding,
+                            width,
+                            height,
+                            background,
+                            foreground,
+                        )
+                        try:
+                            os.makedirs(path)
+                        except OSError as e:
+                            if e.errno != errno.EEXIST:
+                                raise
+                        # Will raise and exception on error
+                        ctx.get_target().write_to_png(filepath)

www/cc-icons.ttf

@@ -0,0 +1,6 @@
+# The contents of this directory are generated by genicons.py
+#
+# Ignore everything in this directory
+*
+# Except this file
+!.gitignore