Add Spearmint portable SDL for Linux compile stuff

Makefile

@@ -418,6 +418,12 @@ ifneq (,$(findstring "$(PLATFORM)", "linux" "gnu_kfreebsd" "kfreebsd-gnu"))
   CLIENT_LIBS=$(SDL_LIBS)
   RENDERER_LIBS = $(SDL_LIBS) -lGL
 
+  ifeq ($(USE_PORTABLE_RPATH),1)
+    # $ is escaped using two, so this is litterly $ORIGIN
+    CLIENT_LIBS+=-Wl,-rpath,'$$ORIGIN/lib/$(ARCH)'
+    RENDERER_LIBS+=-Wl,-rpath,'$$ORIGIN/lib/$(ARCH)'
+  endif
+
   ifeq ($(USE_OPENAL),1)
     ifneq ($(USE_OPENAL_DLOPEN),1)
       CLIENT_LIBS += $(THREAD_LIBS) $(OPENAL_LIBS)

make-linux-portable.sh

@@ -0,0 +1,16 @@
+#!/bin/sh
+
+if [ -z "$1" ]; then
+	echo "Usage: $0 <arch>"
+	echo "  arch can be x86 or x86_64"
+	exit 0
+fi
+
+ARCH=$1
+SDL_PREFIX=/home/zack/Local/SDL-2.0.3/build-$ARCH
+
+SDL_CFLAGS="`$SDL_PREFIX/bin/sdl2-config --cflags`"
+SDL_LIBS="`$SDL_PREFIX/bin/sdl2-config --libs`"
+
+make ARCH=$ARCH USE_PORTABLE_RPATH=1 SDL_CFLAGS="$SDL_CFLAGS" SDL_LIBS="$SDL_LIBS"
+