<!DOCTYPE html> <!--[if IE 8]><html class="no-js lt-ie9" lang="en" > <![endif]--> <!--[if gt IE 8]><!--> <html class="no-js" lang="en" > <!--<![endif]--> <head> <meta charset="utf-8"> <meta name="viewport" content="width=device-width, initial-scale=1.0"> <title>PIL.GimpGradientFile — Pillow (PIL Fork) 5.4.1 documentation</title> <script type="text/javascript" src="../../_static/js/modernizr.min.js"></script> <script type="text/javascript" id="documentation_options" data-url_root="../../" src="../../_static/documentation_options.js"></script> <script type="text/javascript" src="../../_static/jquery.js"></script> <script type="text/javascript" src="../../_static/underscore.js"></script> <script type="text/javascript" src="../../_static/doctools.js"></script> <script type="text/javascript" src="../../_static/language_data.js"></script> <script type="text/javascript" src="../../_static/js/script.js"></script> <script type="text/javascript" src="../../_static/js/theme.js"></script> <link 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role="navigation" aria-label="main navigation"> <ul> <li class="toctree-l1"><a class="reference internal" href="../../installation.html">Installation</a></li> <li class="toctree-l1"><a class="reference internal" href="../../handbook/index.html">Handbook</a></li> <li class="toctree-l1"><a class="reference internal" href="../../reference/index.html">Reference</a></li> <li class="toctree-l1"><a class="reference internal" href="../../porting.html">Porting</a></li> <li class="toctree-l1"><a class="reference internal" href="../../about.html">About</a></li> <li class="toctree-l1"><a class="reference internal" href="../../releasenotes/index.html">Release Notes</a></li> <li class="toctree-l1"><a class="reference internal" href="../../deprecations.html">Deprecations and removals</a></li> </ul> </div> </div> </nav> <section data-toggle="wy-nav-shift" class="wy-nav-content-wrap"> <nav class="wy-nav-top" aria-label="top navigation"> <i data-toggle="wy-nav-top" class="fa fa-bars"></i> <a href="../../index.html">Pillow (PIL Fork)</a> </nav> <div class="wy-nav-content"> <div class="rst-content"> <div role="navigation" aria-label="breadcrumbs navigation"> <ul class="wy-breadcrumbs"> <li><a href="../../index.html">Docs</a> »</li> <li><a href="../index.html">Module code</a> »</li> <li>PIL.GimpGradientFile</li> <li class="wy-breadcrumbs-aside"> </li> </ul> <hr/> </div> <div role="main" class="document" itemscope="itemscope" itemtype="http://schema.org/Article"> <div itemprop="articleBody"> <h1>Source code for PIL.GimpGradientFile</h1><div class="highlight"><pre> <span></span><span class="c1">#</span> <span class="c1"># Python Imaging Library</span> <span class="c1"># $Id$</span> <span class="c1">#</span> <span class="c1"># stuff to read (and render) GIMP gradient files</span> <span class="c1">#</span> <span class="c1"># History:</span> <span class="c1"># 97-08-23 fl Created</span> <span class="c1">#</span> <span class="c1"># Copyright (c) Secret Labs AB 1997.</span> <span class="c1"># Copyright (c) Fredrik Lundh 1997.</span> <span class="c1">#</span> <span class="c1"># See the README file for information on usage and redistribution.</span> <span class="c1">#</span> <span class="kn">from</span> <span class="nn">math</span> <span class="k">import</span> <span class="n">pi</span><span class="p">,</span> <span class="n">log</span><span class="p">,</span> <span class="n">sin</span><span class="p">,</span> <span class="n">sqrt</span> <span class="kn">from</span> <span class="nn">._binary</span> <span class="k">import</span> <span class="n">o8</span> <span class="c1"># --------------------------------------------------------------------</span> <span class="c1"># Stuff to translate curve segments to palette values (derived from</span> <span class="c1"># the corresponding code in GIMP, written by Federico Mena Quintero.</span> <span class="c1"># See the GIMP distribution for more information.)</span> <span class="c1">#</span> <span class="n">EPSILON</span> <span class="o">=</span> <span class="mf">1e-10</span> <div class="viewcode-block" id="linear"><a class="viewcode-back" href="../../PIL.html#PIL.GimpGradientFile.linear">[docs]</a><span class="k">def</span> <span class="nf">linear</span><span class="p">(</span><span class="n">middle</span><span class="p">,</span> <span class="n">pos</span><span class="p">):</span> <span class="k">if</span> <span class="n">pos</span> <span class="o"><=</span> <span class="n">middle</span><span class="p">:</span> <span class="k">if</span> <span class="n">middle</span> <span class="o"><</span> <span class="n">EPSILON</span><span class="p">:</span> <span class="k">return</span> <span class="mf">0.0</span> <span class="k">else</span><span class="p">:</span> <span class="k">return</span> <span class="mf">0.5</span> <span class="o">*</span> <span class="n">pos</span> <span class="o">/</span> <span class="n">middle</span> <span class="k">else</span><span class="p">:</span> <span class="n">pos</span> <span class="o">=</span> <span class="n">pos</span> <span class="o">-</span> <span class="n">middle</span> <span class="n">middle</span> <span class="o">=</span> <span class="mf">1.0</span> <span class="o">-</span> <span class="n">middle</span> <span class="k">if</span> <span class="n">middle</span> <span class="o"><</span> <span class="n">EPSILON</span><span class="p">:</span> <span class="k">return</span> <span class="mf">1.0</span> <span class="k">else</span><span class="p">:</span> <span class="k">return</span> <span class="mf">0.5</span> <span class="o">+</span> <span class="mf">0.5</span> <span class="o">*</span> <span class="n">pos</span> <span class="o">/</span> <span class="n">middle</span></div> <div class="viewcode-block" id="curved"><a class="viewcode-back" href="../../PIL.html#PIL.GimpGradientFile.curved">[docs]</a><span class="k">def</span> <span class="nf">curved</span><span class="p">(</span><span class="n">middle</span><span class="p">,</span> <span class="n">pos</span><span class="p">):</span> <span class="k">return</span> <span class="n">pos</span> <span class="o">**</span> <span class="p">(</span><span class="n">log</span><span class="p">(</span><span class="mf">0.5</span><span class="p">)</span> <span class="o">/</span> <span class="n">log</span><span class="p">(</span><span class="nb">max</span><span class="p">(</span><span class="n">middle</span><span class="p">,</span> <span class="n">EPSILON</span><span class="p">)))</span></div> <div class="viewcode-block" id="sine"><a class="viewcode-back" href="../../PIL.html#PIL.GimpGradientFile.sine">[docs]</a><span class="k">def</span> <span class="nf">sine</span><span class="p">(</span><span class="n">middle</span><span class="p">,</span> <span class="n">pos</span><span class="p">):</span> <span class="k">return</span> <span class="p">(</span><span class="n">sin</span><span class="p">((</span><span class="o">-</span><span class="n">pi</span> <span class="o">/</span> <span class="mf">2.0</span><span class="p">)</span> <span class="o">+</span> <span class="n">pi</span> <span class="o">*</span> <span class="n">linear</span><span class="p">(</span><span class="n">middle</span><span class="p">,</span> <span class="n">pos</span><span class="p">))</span> <span class="o">+</span> <span class="mf">1.0</span><span class="p">)</span> <span class="o">/</span> <span class="mf">2.0</span></div> <div class="viewcode-block" id="sphere_increasing"><a class="viewcode-back" href="../../PIL.html#PIL.GimpGradientFile.sphere_increasing">[docs]</a><span class="k">def</span> <span class="nf">sphere_increasing</span><span class="p">(</span><span class="n">middle</span><span class="p">,</span> <span class="n">pos</span><span class="p">):</span> <span class="k">return</span> <span class="n">sqrt</span><span class="p">(</span><span class="mf">1.0</span> <span class="o">-</span> <span class="p">(</span><span class="n">linear</span><span class="p">(</span><span class="n">middle</span><span class="p">,</span> <span class="n">pos</span><span class="p">)</span> <span class="o">-</span> <span class="mf">1.0</span><span class="p">)</span> <span class="o">**</span> <span class="mi">2</span><span class="p">)</span></div> <div class="viewcode-block" id="sphere_decreasing"><a class="viewcode-back" href="../../PIL.html#PIL.GimpGradientFile.sphere_decreasing">[docs]</a><span class="k">def</span> <span class="nf">sphere_decreasing</span><span class="p">(</span><span class="n">middle</span><span class="p">,</span> <span class="n">pos</span><span class="p">):</span> <span class="k">return</span> <span class="mf">1.0</span> <span class="o">-</span> <span class="n">sqrt</span><span class="p">(</span><span class="mf">1.0</span> <span class="o">-</span> <span class="n">linear</span><span class="p">(</span><span class="n">middle</span><span class="p">,</span> <span class="n">pos</span><span class="p">)</span> <span class="o">**</span> <span class="mi">2</span><span class="p">)</span></div> <span class="n">SEGMENTS</span> <span class="o">=</span> <span class="p">[</span><span class="n">linear</span><span class="p">,</span> <span class="n">curved</span><span class="p">,</span> <span class="n">sine</span><span class="p">,</span> <span class="n">sphere_increasing</span><span class="p">,</span> <span class="n">sphere_decreasing</span><span class="p">]</span> <div class="viewcode-block" id="GradientFile"><a class="viewcode-back" href="../../PIL.html#PIL.GimpGradientFile.GradientFile">[docs]</a><span class="k">class</span> <span class="nc">GradientFile</span><span class="p">(</span><span class="nb">object</span><span class="p">):</span> <span class="n">gradient</span> <span class="o">=</span> <span class="kc">None</span> <div class="viewcode-block" id="GradientFile.getpalette"><a class="viewcode-back" href="../../PIL.html#PIL.GimpGradientFile.GradientFile.getpalette">[docs]</a> <span class="k">def</span> <span class="nf">getpalette</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">entries</span><span class="o">=</span><span class="mi">256</span><span class="p">):</span> <span class="n">palette</span> <span class="o">=</span> <span class="p">[]</span> <span class="n">ix</span> <span class="o">=</span> <span class="mi">0</span> <span class="n">x0</span><span class="p">,</span> <span class="n">x1</span><span class="p">,</span> <span class="n">xm</span><span class="p">,</span> <span class="n">rgb0</span><span class="p">,</span> <span class="n">rgb1</span><span class="p">,</span> <span class="n">segment</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">gradient</span><span class="p">[</span><span class="n">ix</span><span class="p">]</span> <span class="k">for</span> <span class="n">i</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="n">entries</span><span class="p">):</span> <span class="n">x</span> <span class="o">=</span> <span class="n">i</span> <span class="o">/</span> <span class="nb">float</span><span class="p">(</span><span class="n">entries</span><span class="o">-</span><span class="mi">1</span><span class="p">)</span> <span class="k">while</span> <span class="n">x1</span> <span class="o"><</span> <span class="n">x</span><span class="p">:</span> <span class="n">ix</span> <span class="o">+=</span> <span class="mi">1</span> <span class="n">x0</span><span class="p">,</span> <span class="n">x1</span><span class="p">,</span> <span class="n">xm</span><span class="p">,</span> <span class="n">rgb0</span><span class="p">,</span> <span class="n">rgb1</span><span class="p">,</span> <span class="n">segment</span> <span class="o">=</span> <span class="bp">self</span><span class="o">.</span><span class="n">gradient</span><span class="p">[</span><span class="n">ix</span><span class="p">]</span> <span class="n">w</span> <span class="o">=</span> <span class="n">x1</span> <span class="o">-</span> <span class="n">x0</span> <span class="k">if</span> <span class="n">w</span> <span class="o"><</span> <span class="n">EPSILON</span><span class="p">:</span> <span class="n">scale</span> <span class="o">=</span> <span class="n">segment</span><span class="p">(</span><span class="mf">0.5</span><span class="p">,</span> <span class="mf">0.5</span><span class="p">)</span> <span class="k">else</span><span class="p">:</span> <span class="n">scale</span> <span class="o">=</span> <span class="n">segment</span><span class="p">((</span><span class="n">xm</span> <span class="o">-</span> <span class="n">x0</span><span class="p">)</span> <span class="o">/</span> <span class="n">w</span><span class="p">,</span> <span class="p">(</span><span class="n">x</span> <span class="o">-</span> <span class="n">x0</span><span class="p">)</span> <span class="o">/</span> <span class="n">w</span><span class="p">)</span> <span class="c1"># expand to RGBA</span> <span class="n">r</span> <span class="o">=</span> <span class="n">o8</span><span class="p">(</span><span class="nb">int</span><span class="p">(</span><span class="mi">255</span> <span class="o">*</span> <span class="p">((</span><span class="n">rgb1</span><span class="p">[</span><span class="mi">0</span><span class="p">]</span> <span class="o">-</span> <span class="n">rgb0</span><span class="p">[</span><span class="mi">0</span><span class="p">])</span> <span class="o">*</span> <span class="n">scale</span> <span class="o">+</span> <span class="n">rgb0</span><span class="p">[</span><span class="mi">0</span><span class="p">])</span> <span class="o">+</span> <span class="mf">0.5</span><span class="p">))</span> <span class="n">g</span> <span class="o">=</span> <span class="n">o8</span><span class="p">(</span><span class="nb">int</span><span class="p">(</span><span class="mi">255</span> <span class="o">*</span> <span class="p">((</span><span class="n">rgb1</span><span class="p">[</span><span class="mi">1</span><span class="p">]</span> <span class="o">-</span> <span class="n">rgb0</span><span class="p">[</span><span class="mi">1</span><span class="p">])</span> <span class="o">*</span> <span class="n">scale</span> <span class="o">+</span> <span class="n">rgb0</span><span class="p">[</span><span class="mi">1</span><span class="p">])</span> <span class="o">+</span> <span class="mf">0.5</span><span class="p">))</span> <span class="n">b</span> <span class="o">=</span> <span class="n">o8</span><span class="p">(</span><span class="nb">int</span><span class="p">(</span><span class="mi">255</span> <span class="o">*</span> <span class="p">((</span><span class="n">rgb1</span><span class="p">[</span><span class="mi">2</span><span class="p">]</span> <span class="o">-</span> <span class="n">rgb0</span><span class="p">[</span><span class="mi">2</span><span class="p">])</span> <span class="o">*</span> <span class="n">scale</span> <span class="o">+</span> <span class="n">rgb0</span><span class="p">[</span><span class="mi">2</span><span class="p">])</span> <span class="o">+</span> <span class="mf">0.5</span><span class="p">))</span> <span class="n">a</span> <span class="o">=</span> <span class="n">o8</span><span class="p">(</span><span class="nb">int</span><span class="p">(</span><span class="mi">255</span> <span class="o">*</span> <span class="p">((</span><span class="n">rgb1</span><span class="p">[</span><span class="mi">3</span><span class="p">]</span> <span class="o">-</span> <span class="n">rgb0</span><span class="p">[</span><span class="mi">3</span><span class="p">])</span> <span class="o">*</span> <span class="n">scale</span> <span class="o">+</span> <span class="n">rgb0</span><span class="p">[</span><span class="mi">3</span><span class="p">])</span> <span class="o">+</span> <span class="mf">0.5</span><span class="p">))</span> <span class="c1"># add to palette</span> <span class="n">palette</span><span class="o">.</span><span class="n">append</span><span class="p">(</span><span class="n">r</span> <span class="o">+</span> <span class="n">g</span> <span class="o">+</span> <span class="n">b</span> <span class="o">+</span> <span class="n">a</span><span class="p">)</span> <span class="k">return</span> <span class="sa">b</span><span class="s2">""</span><span class="o">.</span><span class="n">join</span><span class="p">(</span><span class="n">palette</span><span class="p">),</span> <span class="s2">"RGBA"</span></div></div> <span class="c1">##</span> <span class="c1"># File handler for GIMP's gradient format.</span> <div class="viewcode-block" id="GimpGradientFile"><a class="viewcode-back" href="../../PIL.html#PIL.GimpGradientFile.GimpGradientFile">[docs]</a><span class="k">class</span> <span class="nc">GimpGradientFile</span><span class="p">(</span><span class="n">GradientFile</span><span class="p">):</span> <span class="k">def</span> <span class="nf">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">fp</span><span class="p">):</span> <span class="k">if</span> <span class="n">fp</span><span class="o">.</span><span class="n">readline</span><span class="p">()[:</span><span class="mi">13</span><span class="p">]</span> <span class="o">!=</span> <span class="sa">b</span><span class="s2">"GIMP Gradient"</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">SyntaxError</span><span class="p">(</span><span class="s2">"not a GIMP gradient file"</span><span class="p">)</span> <span class="n">line</span> <span class="o">=</span> <span class="n">fp</span><span class="o">.</span><span class="n">readline</span><span class="p">()</span> <span class="c1"># GIMP 1.2 gradient files don't contain a name, but GIMP 1.3 files do</span> <span class="k">if</span> <span class="n">line</span><span class="o">.</span><span class="n">startswith</span><span class="p">(</span><span class="sa">b</span><span class="s2">"Name: "</span><span class="p">):</span> <span class="n">line</span> <span class="o">=</span> <span class="n">fp</span><span class="o">.</span><span class="n">readline</span><span class="p">()</span><span class="o">.</span><span class="n">strip</span><span class="p">()</span> <span class="n">count</span> <span class="o">=</span> <span class="nb">int</span><span class="p">(</span><span class="n">line</span><span class="p">)</span> <span class="n">gradient</span> <span class="o">=</span> <span class="p">[]</span> <span class="k">for</span> <span class="n">i</span> <span class="ow">in</span> <span class="nb">range</span><span class="p">(</span><span class="n">count</span><span class="p">):</span> <span class="n">s</span> <span class="o">=</span> <span class="n">fp</span><span class="o">.</span><span class="n">readline</span><span class="p">()</span><span class="o">.</span><span class="n">split</span><span class="p">()</span> <span class="n">w</span> <span class="o">=</span> <span class="p">[</span><span class="nb">float</span><span class="p">(</span><span class="n">x</span><span class="p">)</span> <span class="k">for</span> <span class="n">x</span> <span class="ow">in</span> <span class="n">s</span><span class="p">[:</span><span class="mi">11</span><span class="p">]]</span> <span class="n">x0</span><span class="p">,</span> <span class="n">x1</span> <span class="o">=</span> <span class="n">w</span><span class="p">[</span><span class="mi">0</span><span class="p">],</span> <span class="n">w</span><span class="p">[</span><span class="mi">2</span><span class="p">]</span> <span class="n">xm</span> <span class="o">=</span> <span class="n">w</span><span class="p">[</span><span class="mi">1</span><span class="p">]</span> <span class="n">rgb0</span> <span class="o">=</span> <span class="n">w</span><span class="p">[</span><span class="mi">3</span><span class="p">:</span><span class="mi">7</span><span class="p">]</span> <span class="n">rgb1</span> <span class="o">=</span> <span class="n">w</span><span class="p">[</span><span class="mi">7</span><span class="p">:</span><span class="mi">11</span><span class="p">]</span> <span class="n">segment</span> <span class="o">=</span> <span class="n">SEGMENTS</span><span class="p">[</span><span class="nb">int</span><span class="p">(</span><span class="n">s</span><span class="p">[</span><span class="mi">11</span><span class="p">])]</span> <span class="n">cspace</span> <span class="o">=</span> <span class="nb">int</span><span class="p">(</span><span class="n">s</span><span class="p">[</span><span class="mi">12</span><span class="p">])</span> <span class="k">if</span> <span class="n">cspace</span> <span class="o">!=</span> <span class="mi">0</span><span class="p">:</span> <span class="k">raise</span> <span class="ne">IOError</span><span class="p">(</span><span class="s2">"cannot handle HSV colour space"</span><span class="p">)</span> <span class="n">gradient</span><span class="o">.</span><span class="n">append</span><span class="p">((</span><span class="n">x0</span><span class="p">,</span> <span class="n">x1</span><span class="p">,</span> <span class="n">xm</span><span class="p">,</span> <span class="n">rgb0</span><span class="p">,</span> <span class="n">rgb1</span><span class="p">,</span> <span class="n">segment</span><span class="p">))</span> <span class="bp">self</span><span class="o">.</span><span class="n">gradient</span> <span class="o">=</span> <span class="n">gradient</span></div> </pre></div> </div> </div> <footer> <hr/> <div role="contentinfo"> <p> © Copyright 1995-2011 Fredrik Lundh, 2010-2018 Alex Clark and Contributors </p> </div> Built with <a href="http://sphinx-doc.org/">Sphinx</a> using a <a href="https://github.com/rtfd/sphinx_rtd_theme">theme</a> provided by <a href="https://readthedocs.org">Read the Docs</a>. </footer> </div> </div> </section> </div> <script type="text/javascript"> jQuery(function () { SphinxRtdTheme.Navigation.enable(true); }); </script> </body> </html>