Trade: implement passing importer/converter options to imageconverter.

doc/changelog.dox

@@ -313,6 +313,12 @@ See also:
 -   New @ref Text::AbstractFont::setFileCallback() to allow opening multi-file
     fonts with an API similar to @ref Trade::AbstractImporter
 
+@subsubsection changelog-latest-new-trade Trade library
+
+-   The @ref magnum-imageconverter "magnum-imageconverter" utility now
+    implements new `-i` / `--importer-options` and `-c` / `--converter-options`
+    command-line options for setting plugin-specific configuration
+
 @subsection changelog-latest-changes Changes and improvements
 
 -   The @ref ResourceManager class now accepts also

src/Magnum/Trade/imageconverter.cpp

@@ -24,10 +24,13 @@
 */
 
 #include <Corrade/Containers/Optional.h>
+#include <Corrade/Containers/StaticArray.h>
 #include <Corrade/PluginManager/Manager.h>
 #include <Corrade/Utility/Arguments.h>
+#include <Corrade/Utility/ConfigurationGroup.h>
 #include <Corrade/Utility/DebugStl.h>
 #include <Corrade/Utility/Directory.h>
+#include <Corrade/Utility/String.h>
 
 #include "Magnum/PixelFormat.h"
 #include "Magnum/Trade/AbstractImporter.h"
@@ -88,6 +91,33 @@ magnum-imageconverter image.jpg image.png
 
 using namespace Magnum;
 
+namespace {
+
+void setOptions(PluginManager::AbstractPlugin& plugin, const std::string& options) {
+    for(const std::string& option: Utility::String::splitWithoutEmptyParts(options, ';')) {
+        auto keyValue = Utility::String::partition(option, '=');
+        Utility::String::trimInPlace(keyValue[0]);
+        Utility::String::trimInPlace(keyValue[2]);
+
+        /* Provide a warning message in case the plugin doesn't define given
+           option in its default config. The plugin is not *required* to have
+           those tho (could be backward compatibility entries, for example), so
+           not an error. */
+        if(!plugin.configuration().valueCount(keyValue[0]))
+            Warning{} << "Option" << keyValue[0] << "not recognized by" << plugin.plugin();
+
+        /* If the option doesn't have an =, treat it as a boolean flag that's
+           set to true. While there's no similar way to do an inverse, it's
+           still nicer than causing a fatal error with those. */
+        if(keyValue[1].empty())
+            plugin.configuration().setValue(keyValue[0], true);
+        else
+            plugin.configuration().setValue(keyValue[0], keyValue[2]);
+    }
+}
+
+}
+
 int main(int argc, char** argv) {
     Utility::Arguments args;
     args.addArgument("input").setHelp("input", "input image")
@@ -95,7 +125,15 @@ int main(int argc, char** argv) {
         .addOption("importer", "AnyImageImporter").setHelp("importer", "image importer plugin")
         .addOption("converter", "AnyImageConverter").setHelp("converter", "image converter plugin")
         .addOption("plugin-dir").setHelp("plugin-dir", "override base plugin dir", "DIR")
-        .setGlobalHelp("Converts images of different formats.")
+        .addOption('i', "importer-options").setHelp("options", "configuration options to pass to the importer", "key=val,key2=val2,…")
+        .addOption('c', "converter-options").setHelp("options", "configuration options to pass to the converter", "key=val,key2=val2,…")
+        .addOption("raw").setHelp("raw", "treat the image as raw pixels of given format", "FORMAT")
+        .setGlobalHelp(R"(Converts images of different formats.
+
+The -i / --importer-options and -c / --converter-options arguments accept a
+comma-separated list of key/value pairs to set in the importer / converter
+plugin configuration. If the = character is omitted, it's equivalent to saying
+key=true.)")
         .parse(argc, argv);
 
     /* Load importer plugin */
@@ -112,6 +150,10 @@ int main(int argc, char** argv) {
     Containers::Pointer<Trade::AbstractImageConverter> converter = converterManager.loadAndInstantiate(args.value("converter"));
     if(!converter) return 2;
 
+    /* Set options, if passed */
+    setOptions(*importer, args.value("importer-options"));
+    setOptions(*converter, args.value("converter-options"));
+
     /* Open input file */
     Containers::Optional<Trade::ImageData2D> image;
     if(!importer->openFile(args.value("input")) || !(image = importer->image2D(0))) {