automatic multiprocessor builds, fix compilation when COLLADA is missing

SConstruct

@@ -3,6 +3,7 @@ import sys
 import glob
 import os
 import fnmatch
+import multiprocessing
 
 if not os.path.exists('config.py'):
 	print 'A configuration file must be selected! Have a look at \"README\"'
@@ -66,6 +67,10 @@ if env.has_key('BOOSTINCLUDE'):
 if env.has_key('BASELIBDIR'):
 	env.Append(LIBPATH=env['BASELIBDIR'])
 
+env.Decider('MD5-timestamp')
+
+env.SetOption('num_jobs', multiprocessing.cpu_count())
+
 AddOption("--dist", dest="dist", type="string", nargs=0, action='store', help='Make an official release')
 
 # Check whether everything important is available
@@ -205,6 +210,9 @@ def osxlibinst_build_function(self, target, source, pkgname = None, use_own = No
 env.__class__.StripInst = stripinst_build_function
 env.__class__.OSXLibInst = osxlibinst_build_function
 
+if hasCollada:
+	env.Append(CPPDEFINES = [['MTS_HAS_COLLADA', 1]] )
+
 env.SConsignFile()
 
 # MSVC: Embed the manifest
@@ -240,7 +248,7 @@ if coreEnv.has_key('JPEGINCLUDE'):
 if coreEnv.has_key('JPEGLIB'):
 	coreEnv.Append(LIBS=env['JPEGLIB'])
 
-coreEnv.Append(CPPDEFINES = {'MTS_BUILD_MODULE' : 'MTS_MODULE_CORE'} )
+coreEnv.Append(CPPDEFINES = [['MTS_BUILD_MODULE', 'MTS_MODULE_CORE']])
 libcore_objects = [
 	'src/libcore/class.cpp', 'src/libcore/object.cpp', 
 	'src/libcore/statistics.cpp', 'src/libcore/thread.cpp',
@@ -276,7 +284,7 @@ env.Append(LIBPATH=['src/libcore'])
 
 # Rendering-specific library
 renderEnv = env.Clone()
-renderEnv.Append(CPPDEFINES = {'MTS_BUILD_MODULE' : 'MTS_MODULE_RENDER'} )
+renderEnv.Append(CPPDEFINES = [['MTS_BUILD_MODULE', 'MTS_MODULE_RENDER']] )
 if renderEnv.has_key('XERCESINCLUDE'):
 	renderEnv.Append(CPPPATH=renderEnv['XERCESINCLUDE'])
 if renderEnv.has_key('XERCESLIBDIR'):
@@ -330,7 +338,7 @@ elif sys.platform == 'linux2':
 		'src/libhw/glxrenderer.cpp']
 
 glEnv = env.Clone()
-glEnv.Append(CPPDEFINES = {'MTS_BUILD_MODULE' : 'MTS_MODULE_HW'} )
+glEnv.Append(CPPDEFINES = [['MTS_BUILD_MODULE', 'MTS_MODULE_HW']] )
 if glEnv.has_key('GLLIB'):
 	glEnv.Append(LIBS=glEnv['GLLIB'])
 if glEnv.has_key('GLLIBDIR'):
@@ -423,6 +431,7 @@ if hasQt:
 	qtEnv = mainEnv.Clone()
 	qtEnv.Append(CPPPATH=['src/qtgui'])
 	qtEnv.EnableQt4Modules(['QtGui', 'QtCore', 'QtOpenGL', 'QtXml', 'QtNetwork'])
+	print(qtEnv.Dump())
 	if sys.platform == 'win32':
 		index = qtEnv['CXXFLAGS'].index('_CONSOLE')
 		del qtEnv['CXXFLAGS'][index-1]
@@ -449,6 +458,7 @@ if hasQt:
 
 	if sys.platform == 'darwin':
 		qtEnv_osx = qtEnv.Clone();
+		# Objective C++ does not permit the following optimization flags
 		qtEnv_osx['CXXFLAGS'].remove('-fstrict-aliasing');
 		qtEnv_osx['CXXFLAGS'].remove('-ftree-vectorize');
 		qtEnv_osx['CXXFLAGS'].append('-fno-strict-aliasing');

src/qtgui/mainwindow.cpp

@@ -443,6 +443,7 @@ void MainWindow::onBugReportSubmitted() {
 }
 
 void MainWindow::on_actionImport_triggered() {
+#if defined(MTS_HAS_COLLADA)
 	ref<FileResolver> resolver = FileResolver::getInstance();
 	ref<FileResolver> newResolver = resolver->clone();
 	for (int i=0; i<m_searchPaths.size(); ++i)
@@ -457,6 +458,13 @@ void MainWindow::on_actionImport_triggered() {
 	dialog->show();
 	qApp->processEvents();
 	m_activeWindowHack = false;
+#else
+	QMessageBox::critical(this, tr("Importer disabled"),
+		tr("The importer is disabled in this build. To use it, you will need "
+		"to install COLLADA-DOM and recompile Mitsuba -- please see the "
+		"documentation for more details."), 
+		QMessageBox::Ok);
+#endif
 }
 
 void MainWindow::onImportDialogClose(int reason) {

src/qtgui/sceneimporter.cpp

@@ -52,6 +52,7 @@ SceneImporter::~SceneImporter() {
 
 void SceneImporter::run() {
 	FileResolver::setInstance(m_resolver);
+#if defined(MTS_HAS_COLLADA)
 	try {
 		GUIGeometryConverter cvt(m_parent);
 		cvt.setSRGB(m_srgb);
@@ -62,6 +63,9 @@ void SceneImporter::run() {
 	} catch (...) {
 		SLog(EWarn, "An unknown type of error occurred!");
 	}
+#else
+	SLog(EWarn, "The importer was disabled in this build!");
+#endif
 	m_wait->set(true);
 }