Document SVG scaling & add an FAQ for it.

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/trunk@196368 13f79535-47bb-0310-9956-ffa450edef68

src/documentation/content/xdocs/faq.xml

@@ -598,7 +598,7 @@ See <link href="#usercfg">loading the user configuration file</link> for further
     </faq>
   </part>
   <part id="part-svg">
-    <title>Batik/SVG specific questions</title>
+    <title>SVG specific questions</title>
     <faq id="svg-text">
       <question>The rendering of SVG text in my PDF is of poor quality.
 Can I control this?</question>
@@ -693,6 +693,12 @@ Can I control this?</question>
         <p>See also <link href="#MalformedURL">MalformedURLException</link></p>
       </answer>
     </faq>
+    <faq id="svg-scaling">
+      <question>Why is my SVG rendered at a size different from that specified in my fo:external-graphic element?</question>
+      <answer>
+        <p>See <link href="graphics.html#svg-scaling">SVG Scaling</link>.</p>
+      </answer>
+    </faq>
   </part>
   <part id="part-pdf">
     <title>PDF specific (includes Acrobat peculiarities)</title>

src/documentation/content/xdocs/graphics.xml

@@ -240,6 +240,13 @@ to an integer value. In future this will be improved.
         <p>Note that because SVG text can be rendered as either text or a vector graphic, you may need to consider settings in your viewer for both.
 The Acrobat viewer has both "smooth line art" and "smooth text" settings that may need to be set for SVG images to be displayed nicely on your screen (see Edit / Preferences / Display).
 This setting will not affect the printing of your document, which should be OK in any case, but will only affect the quality of the screen display.</p>
+      </section>
+      <section id="svg-scaling">
+        <title>Scaling</title>
+        <p>Currently, SVG images are rendered with the dimensions specified <em>in the SVG file</em>, within the viewport specified in the fo:external-graphic element.
+For everything to work properly, the two should be equal.
+The SVG standard leaves this issue as an implementation detail.
+FOP will probably implement a scaling mechanism in the future.</p>
       </section>
       <section id="svg-problems">
         <title>Known Problems</title>