Make it buildable for Android with QtCreator

CMakeLists.txt

@@ -14,6 +14,8 @@ SET(CMAKE_INSTALL_RPATH "${CMAKE_INSTALL_PREFIX}/lib")
 # which point to directories outside the build tree to the install RPATH
 set(CMAKE_INSTALL_RPATH_USE_LINK_PATH TRUE)
 
+add_definitions(-DLINUX) # for compatibility with Android and Windows builds with QtCretino
+
 option(V4L-RTL "Use Linux Kernel RTL-SDR Source." OFF)
 option(V4L-MSI "Use Linux Kernel MSI2500 Source." OFF)
 option(BUILD_TYPE "Build type (RELEASE, RELEASEWITHDBGINFO, DEBUG" RELEASE)

sdrangel.pro

@@ -4,7 +4,7 @@
 #
 #--------------------------------------------------------
 
-QT       += core gui
+QT       += core gui multimedia opengl
 
 greaterThan(QT_MAJOR_VERSION, 4): QT += widgets
 
@@ -12,17 +12,8 @@ TARGET = sdrangel
 TEMPLATE = app
 INCLUDEPATH += $$PWD/include
 
-CONFIG(ANDROID):INCLUDEPATH += /opt/install/Qt/5.5/android_armv7/include/QtGui
-CONFIG(ANDROID):INCLUDEPATH += /opt/install/Qt/5.5/android_armv7/include/QtMultimedia
-CONFIG(ANDROID):INCLUDEPATH += /opt/install/Qt/5.5/android_armv7/include/QtOpenGL
-CONFIG(ANDROID):INCLUDEPATH += /opt/install/Qt/5.5/android_armv7/include/QtOpenGLExtensions
-#INCLUDEPATH += $$(BOOST_PATH)
 CONFIG(ANDROID):INCLUDEPATH += /opt/build/Boost-for-Android-Prebuilt/boost_1_53_0/include
-CONFIG(ANDROID):INCLUDEPATH += /opt/install/android-ndk-r10e/platforms/android-21/arch-arm/usr/include
-
 CONFIG(MINGW32):INCLUDEPATH += "D:\boost_1_55_0"
-CONFIG(MINGW32):QT += multimedia
-CONFIG(MINGW32):QT += opengl
 
 SOURCES += main.cpp\
         sdrbase/mainwindow.cpp\

sdrbase/dsp/scopevis.cpp

@@ -6,6 +6,13 @@
 
 #include <QDebug>
 
+#ifndef LINUX
+inline double log2f(double n)
+{
+	return log(n) / log(2.0);
+}
+#endif
+
 MESSAGE_CLASS_DEFINITION(ScopeVis::MsgConfigureScopeVis, Message)
 
 const uint ScopeVis::m_traceChunkSize = 4800;

sdrbase/dsp/spectrumvis.cpp

@@ -5,8 +5,8 @@
 
 #define MAX_FFT_SIZE 4096
 
-#ifdef _WIN32
-double log2f(double n)
+#ifndef LINUX
+inline double log2f(double n)
 {
 	return log(n) / log(2.0);
 }