scons: Add option to enable floating-point textures.

Signed-off-by: Vinson Lee <vlee@freedesktop.org>
Reviewed-by: José Fonseca <jfonseca@vmware.com>

common.py

@@ -98,5 +98,6 @@ def AddOptions(opts):
 	opts.Add(BoolOption('debug', 'DEPRECATED: debug build', 'yes'))
 	opts.Add(BoolOption('profile', 'DEPRECATED: profile build', 'no'))
 	opts.Add(BoolOption('quiet', 'DEPRECATED: profile build', 'yes'))
+	opts.Add(BoolOption('texture_float', 'enable floating-point textures and renderbuffers', 'no'))
 	if host_platform == 'windows':
 		opts.Add(EnumOption('MSVS_VERSION', 'MS Visual C++ version', None, allowed_values=('7.1', '8.0', '9.0')))

scons/gallium.py

@@ -298,6 +298,10 @@ def generate(env):
         cppdefines += ['BEOS_THREADS']
     if env['embedded']:
         cppdefines += ['PIPE_SUBSYSTEM_EMBEDDED']
+    if env['texture_float']:
+        print 'warning: Floating-point textures enabled.'
+        print 'warning: Please consult docs/patents.txt with your lawyer before building Mesa.'
+        cppdefines += ['TEXTURE_FLOAT_ENABLED']
     env.Append(CPPDEFINES = cppdefines)
 
     # C compiler options